E - 463 \ AWlf HOAR*8N!TED STATES DEPARTMENT OF AGRICULTURE BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE DIVISION OF INSECTICIDE INVESTIGATIONS A DIGEST OF THE LITERATURE THROUGH 1934 RELATING TO INSECTICIDAL SPRAY RESIDUES BY R. L. BUSBEY Washington, D. C February 1939 E- 463 February 1939 United States Department of Agriculture Bureau of Entomology and Plant Quarantine A DIGEST OE THE LITERATURE THROUGH 1934 RELATING TC DTSSCTICIDAL SPRAY RESIDUES By R. L. Busbey, Division of Insecticide Investigations Contents Page Introduction 2 - I. Public health aspects of the spray residue problem 3 IT. Legal aspects of the spray residue problem 32 III. Removal of spray residues from fruits and vegetables 59 A. Processes 59 B. Apparatus •_•____•__•___' 129 IV. Relation of spray program to residue • 138 V. Methods of analysis for spriy residues 168 A. Arsenic : 168 E. Lead • r — 181 C. Fluorine, sulphur, copper, spray oils, etc 188 VI. Resxilts of analyses of sprayed fruits and vegetables 191 VII. General -nd unclassified articles on the spray residue problem 210 - 2 - INTRODUCTION The purpose of this publication is to "bring together references to the numerous articles relating to insecticidal spray residues that have appeared in the last ten years. A voluminous literature on this subject now exists, a literature that is widely scattered through horticultural, entomological, medical, chemical, and legal publications as well as in annual reports, "bulletins, and circulars of State and Federal agricultural experiment stations. In spite of the advances that have been made since 1926 in methods and apparatus for removing spray residues of lead arsenate and other in- secticides from apples, improvements in "both processes and machinery designed for washing fruits and vegetables are possible. Since progress can "be made only when a knowledge is had of what has been done, this digest should prove useful to researchers in this field. At present the United States Department of Agriculture tolerances for insecticidal residues on fruits are as follows: Grain per pound Arsenic (expressed as AS2O3) 0.01 Lead (expressed as Pb) 0,025 Fluorine (expressed as F) 0.02 To facilitate finding information in this compilation it has been arranged in parts which group articles dealing with the various phases of the subject. Author and subject indexes are provided in which reference is made to publications by numbers. References to articles in this digest were obtained chiefly from the following abstract journals: Chemical Abstracts, 1907-1934 inclusive; Agricultural Index, 1917-1934 inclusive; Experiment Station Record, through volume 70, 1934; Review of Applied Entomology, Series A, 1913-1933' inclu- sive; Chemisches Zentralblatt , 1926-1932, inclusive; Index of American Economic Entomology, volumes I to IV; and the card index of Miss Mabel Colcord, Librarian, Bureau of Entomology and Plant Quarantine. -3- I, PUBLIC HEALTH ASPECTS OP THE SPRAY RESIDUE PROBLEM ANONYMOUS (1) I SALI DI ARSENICO IN VITICOLTURA ED IN AGRICOLTURA. Rivista di Agricoltura [Parma] 19: 499, 1913. In products derived from plants treated with arsenical compositions, arsenic is often found, generally in minimum doses but often up to 2 mg. per kg, of fruit and 1 mg. per liter of wine. These quantities of poison are harmless when considered "by themselves, but when the greater part of one's food is in the above-mentioned condition, the daily use of such food would pro- duce slow and unavoidable chronic poisoning. (2) L'INPIEGO DEGLI INSETTICIDI ARSENICALI E I SUOI PERICOLI IGIENICI. Minerva Agraria 7 (5-7); 93. 1915. Translated from Arb. a. d. Rais. Gesundheitsarate 29: 11. 1915. (3) DAMAGING PRESS PUBLICITY. Ped. Brit. Growers Jour. 2: 181-182. 1923. Two newspaper articles reporting the warning of a scientist concerning dangerous amounts of arsenic and copper sulphate on sprayed fruits, and a letter written to the editors of the papers by the secretary of the Federation of British Growers, denying the truth of the statement, are quoted. Readers are urged to report immediately any such adverse publicity appearing in newspapers, so that it may be replied to promptly. (4) DANGER OP ARSENIC IN CLOTHING. Jour. *mer. Med, Assoc. 80: 1072. 1923. An a,rsenical solution containing the equivalent of 0.05 percent arsenic pentoxide has been advertised as a larvi- cidal spray for the moth-proofing of clothing. Pollution of the air when the clothing is brushed, poisoning of infants by sucking treated woolens, and the development of skin rashes due to contact with treated under clothing are dangerous possi- bilities. It is hoped that dealers in wool clothing will not be parties to the distribution of this potent poison. (5) ARSENIC IN APPLES. Lit. Dig. 88 (8): 26. 1926. This statement is based on an article in The Lancet L_ 4 ~ deploring the use of lead arsenate on fruit trees and point- ing out the danger of poisoning by the residual arsenic on the fruit. (6) POISONING BY iJISENICAL SPRAYS. Amer. Jour. Pud. Health 16; 403. 1926. An editorial, discussing cases of arsenical poisoning in England which were traced to the eating of American apples. (7) THE ARSENIC SCARE. Citrus Leaves 6 (2): 30. 1926. Considerable undesirable publicity on American apples has gotten across to British consumers, and therefore harm has been done to the apple export business because of the associa- tion of illness with the eating of apples coa/ted with arsenical spray residue. (8) PPLANZENSCHUTZ UND BIENENSCHUTZ. Vortragsreihe des Reichsaus- schusses fur Bienenzucht. 32 pp» Anklam. 1931, Includes; K. H. Kickhoffel, Plant protection and apicul- ture; H. Iviorstatt, The necessity for poisons in plant protection; A»Borchert, The effect of poisonous insecticides on bees; Hil- gendorff, The determina/t ion of arsenic in bees; W. Trappmann, The use of poisons for combating pests of orchards, vines, and field crops; M. Voelkel, The use of poisons against forest pests; H. Gotze, The dangers to apiculture of the use of poisonous insecti- cides. (9) POISONOUS INSECTICIDES AND PLANT SPRAYS. J ur. Aaer. Med. Assoc. 101: 126-127. 1933. An editorial. A symposium on insecticides appearing in Industrial and Engineering Chemistry [25: 616. 1933 ] is dis- cussed. Parmers and fruit growers insist there is no danger from lead and a.rsenic as used on fruits. They do not appreciate the danger of cumulative chronic poisoning. The user should thoroughly wash and cleanse fruits and vegetables before putting them on the table either raw or cooked, and perhaps should strip the outer layers from lettuce, cabbage, and similar vegetables. (10) GIRL DIES, 2 MiJJE ILL BY INSECTICIDE, phila. Record. July 17, 1934. ~5- The death of a 3 year old girl and the serious illness of two companions is reported as caused "by eating "beans which had "been sprayed with arsenate of lead to kill Japanese beetles. (11) SCIENTISTS HUNT NEW 7/AYS TO KILL mOK&S. Better Fruit 29 (10): 4-5. 1935. Because of the great interest in the health aspect of the use of lead arsenate on apples and pears, the problem of codling moth control has he come difficult. Federal and State horticul- turists have developed machinery and solutions for removing poi- sonous residues. aMBRUSTER, H. I?. (12) THE PROBLEM OF ARSENICAL SPIUY RESIDUE. Jour. Franklin Inst. 206; 597-604. 1928. A brief history and discussion of the spray residue problem. This is primarily a problem which must be settled first in terms of toxicology and physiology and all other phases of it worked out from a basis of standards set by those sciences. ANDREW, R. L. . (13) ARSENIC IN NEW- ZEALAND-GROWN APPLES. New Zealand Jour. Sci. and Tech. 9; 206-209. 1927. ALthough the minimum medicinal dose of arsenic is l/32 grain, quantities as low a,s l/40 gra,in may cause symptoms of poisoning in susceptibles persons. Results of analyses on sprayed apples show that with ordinary spraying practice, and provided there is an interval of 12 to 15 days between the last spraying and picking, there is no risk of the a.rsenic "being in excess of l/lOO gra.in per pound. Wiping is proba.bly of no value for removing arsenic except when patches of dry spray a.re visible on the fruit. APP, F. (14) SPRAY RESIDUES. Amer. Agr. 131 (19): 6, 27. 1934. An article on spray residues appearing in the Philadel- phia Inquirer on August 19, 1934, is criticized as giving the impression to the hasty reader that all fruits and vegetables are dangerous, iviost vegetables are trimmed and wa.shed by the producer, making it pra,ctically impossible to carry residue to the consumer's table. ~6- BEIJERS, J. A. ' (15) KOPERVERGIFTIGING 3IJ SCHAPEN. Tijdschr. Diergeneesk. 59: 1317-1324. 1932. [English summary.] The author describes a few cases of chronic copper poisoning in sheep which had "been grazing in orchards sprayed with a solution of copper sulphate. BOAZ, V. T. (16) THESE APPLE PEELINGS AGAIN. Better Fruit 28 (2): 8-9. 1933. A satirical editorial making light of the alleged dan- gers of spray residues and, in effect, criticizing the policy of the United States Department of Agriculture of not comment- ing on the merits of insecticides marketed under proprietary names, BORCHERT (17) UNTERSUCHUNG UBER DIE GIFTWIRKUNG XUPFEEHALTIGER VERBINDUNG BEL DEN BLSNEN. Berl. Tierartz. Wchnschr. 1; 84. 1930. [Abstract in Rev. Appl. Myccl. 9; 664-665. 1930.] Bees in lots of 100 were fed on copper-containing plant protectives, copper sulfate and "basic copper carbonate (plus powdered sugar and honey water) in varying concentration, and a concentration at which 25 percent of the insects were killed was determined. The toxic dose of 5 copper-containing fungicides was 8.8 micrograms of metallic copper, and the figures for the other copper co impounds were approximately the seme. These disinfectants being naturally hitter end not as a rule arti- ficially sweetened, the danger to bees from their use may be considered negligible. BRODSXII, I. (18) THE TOXICITY OP ACID COPPER CARBONATE SPRaYS ON THE ANLviAL ORGANISM. Arch. Gewerbepath. Gewerbehyg. 5; 91-107. 1933. [In German.] CAZENEUVE, P. (19) LE DANGER DE L» INTOXICATION ARSENIOALE ET PLOmBEIQUE EN AGRICULTURE. Rev. Vitic. 41; 29-34. 1914. Lead arsenate should not bo used as an agricultural insecticide because of the danger to the health of those em- ploying it and those consuming the products so treated. Ex- amples of illness due to its use are given. -7- (20) F,,TAL INTOXICATIONS BY ^RSENIC IN VI T I CULTURAL DISTRICTS. Bui. Acad, ivied. [Paris] 85: 660-671. 1921. [In French.] GE.ttPELLI.3R, A., ana RAUCOUS? , M. (21) i L* TOXIC ITE ENVERS LE GIEIER DES INSECTICIDES ARS3NICAUX. Cornpt. Rend. AcacL Agr. France 20: 598-603. 1934. The toxicity of several arsenical insecticides to the rabbit and hare was studied and the following conclusions were reached: 1. Diplumbic arsenate is the least dangerous of the insoluble arsenicals employed as insecticides. 2. Paris green is the most toxic, at least 6 times more so than lead arsenate. 3. Tricalcium arsenate and aluminum arsenate have an intermediate toxicity. 4. The repeated absorption of quantities of poison distinctly lower than the fatal doses did not appear to be able to provoke slow intoxications. CHOTY, R. (22) THE D.ITG-ER OF THE USE OF ARSSHEC COi.^OUNDS IN VITICULTURE. Ann. Hyg. Publ. Indus. Sociale 1930: 303-304. [in French.] CLARK2, J. 0. (23) THE SPRAT RESIDUE PROBLEM. Kans. State Hort. Soc. Bien. Rpt. 40: 59-77. 1930. Lead and arsenic spray residues are discussed from the point of vie; of public health. Recommendations for washing fruit with hydrochloric acid are based on U. S. Deot. Agr. Bull. 59. CLOVES, E. S. (24) POISON IN SMALL DOSES; HOW THE CHEMICAL WARFARE AGAINST INSECTS iiFFECTS OUR FOOD SUPPLY. Hygeia 5 : 456-461. Illus. 1927. It is highly probable that every person who eats a fa.ir- ly wide diet, including especially fresh fruits and vegetables, and who does not take some pains to see that they are carefully washed before eating, swallows a measurable amount of arsenic and lead every day, an amount far below e.ny dosage likely to cause symptoms of illness but the ultimate effects cf which may • --8- be serious. Fruit should always be peeled or washed or wiped thoroughly, especially if a gray residue is visible on its sur- face. Vegetables such as celery and lettuce should be thoroughly washed. All competent authorities agree that there is nothing in the situation to be alarmed about. Fruit and vegetables are good foods and nobody is known to have been even made seriously ill from eating them. Furthermore, the growers are alarmed at the reaction already resulting from the action of health authorities and are taking all precautions to rid their products of the last traces of poison. COX, H. E. (25) THE OCCURRENCE OF ARSENIC IN APPLES. Analyst 51: 132-137. 1926. Two cases of poisoning were reported in Hempstead and suspicion fell on certain imported Jonathan apples. These were found to contain 8 parts per million of arsenic as arsenious oxide and 28 parts per million of lead. Of 39 samples of Ameri- can apples examined, only 5 were free of arsenic. There could be no reasonable doubt that the presence of the arsenic was due to the use of arsenates as insecticides for spraying the fruit. DAHMER, G. , and METER, H. (26) UffiEESSUCHUNGEH UBER DEN ARSEN- UND BLEIGEHALT AN 05 ST IM GEFOLGS DER SCHA^LINGSBEKAMPFUNG. Geisenheimer Mitt. 43 (1): 3-8. 1928. [.Abstract in Zentbl. gesamte Hyg. u. Grenzgebiete 17: 346-347. 1923.] The araanic and lead content of apples, grapes, and cur- rants' treated with "Nosprasen" (a lead arsenate preparation) and lead arsenate, and of currant marmalade, jelly, etc., are given in tables. Special attention is devoted to the amount of fruit which would cause harm if eaten. Lead, in contrast with arsenic, is a cumulative poison. Repeated consumption of amounts of arsenic under 0.03 grain cause no harm to man, but amount of about 0.004 grain of lead ingested with fruit daily for months lead to chronic lead poisoning. Especially injurious is the consump- tion of currant marmalade made from fruit growing in orchards, and standing under trees treated with lead arsenate. Even when the currants are washed before use, the lead content is still quite considerable and there is the possibility of the daily con- sumption of about 350 grain or more,' leading to lead poisoning. DAVIS, J. J. , et al. (27) [SPRAY RESIDUE REMOVAL.] Ind. State Hort. Soc. Trans. 72: 31-32. 1933. -9- There is an increasing sentiment on the part of the pub- lic against fruit and vegetables sprayed with arsonicals. Studies are being me.de toward the development of effective and practical non-arsenical sprays. DE EDS, F. (28) CHRONIC FLUORINE INTOXICATION. Medicine 12: 1-60. 1933. The distribution of fluorine is so widespread that a small intake of the element is practically unavoidable. A daily intake of 0.1 to 0.15 mg, of fluorine per Kg. of body weight is capable of producing at least one important mani- festation of chronic poisoning, i. e. , mottled teeth. Therefore the use of fluorine compounds as insecticides or fumigants for plants or foods should bs limited to conditions where satisfactory removal of fluorine residues can be carried oat before placing the food on the market. Chemical analyses should be made on a wide variety of foods grown and prepared ur.der conditions where the fluorine content is acquired solely through natural processes, and on the basir of these analyses a tolerance limit for added fluorine should be specified. A bibliography of 128 references is given. (29) COMPARATIVE TOXICITIES, WITH SPECIAL BEEERENCS TO ARSENICAL AND FLUORINE-CONTAIITING HISECTICIDES. Jour. Econ. Ent. 26 : 302-304. 1933. Recent investigation has shown that a definite abnormal- ity of the teeth may be produced in experimental rats by concen- trations of fluorine which do not retard growth. Srqyth and Smyth, using this as an index of toxicity, conclude that arseni- cal compounds a„re several times more toxic than fluorine insec- ticides. In view of the wide variation in different species in susceptibility to toxicity of a given agent and in view of the extremely low concentration of fluorine in the or ink in water at St. David, Ariz., en endemic area for mottled teeth, it would not be surprising to find eventually that in man the margin of safety for fluorine insecticides is no greater than for arsenical materials. Until the Icv/ost possible threshold tolerax.c for fluorine compounds has been established in sever- al species, and until the fullest use has been made of informa- tion to be gleaned from areas where mottling of teeth is endemic, the question of the wisdom of substituting fluorine~conta.ining insecticides for lea.d arsenate must remain an open one. DEGRULLY, L. (30) PHicAbTIOivS A PRENDRE POUR L'Ei.PLCI DES ARSENICAUX. Progres Agr. et Vitic. 73: 464*465. 1922. -10- Lea.ves which nave undergone a treatment with arsenical products should not be used to wrap any alimentary substance* They should not be used,, in any case, as foci for live-stock. E[SCHEEICH], K. (31) ii ZUEl ARSENEIlaGE. GEGEN EINE BESCHEANKOTG DEE VMY/ENDUNG AHSEN- ff ALTIGER AilTTEL IM IgBIKBAU. Ztschr. Angew. Ent. 8; 165-187. 1921. Several authorities are qaotod on the question of the use of arsenicals in vineyards. The ferr of poisoning fro this source is e:sagge rated. ■om EVANS, W. V. (32) ARSENIC POISONING EBCaI SPHAY3D ASPARAGUS. Jour, hiner. Med. Assoc. 99: 2202-2203. 1932. A number of ./omen who attended a dinner where fresh aspara- gus was served were taissRa violently ill with symptoms suggesting arsenic posioning. Two bur.chcs of bhe asparagus used were ana- lyzed and one was found to coittl&iin a little arsenic, while the other contained arsenic much in excess of the amount tolerated oy the pure food laws. FAES, E. , TONDU2, P. , PIGUE'I, G* , and STAGHELIN, ii. (33) LES SEES AHSENICAuX EN AGRICULEUE3. Ann. Agr. Suisse 24; 315-338. 1923. Arsenic compounds are dangerous absorptive poisons. Ar- senicad treatments of vegetables should be carried out very early so that a considerable interval separates the time of treatment from the time of consumption. Experiments carried cat against the apple worm show that the quantity of arsenic remaining at harvest on the skin of the treated fruits is very small [from less than 0,0001 to 0.01 mg. per 10 g. of skirsj and cannot exert an unfavor- able action on the human organism. The flesh of the tree. ted fruits contains only negligible traces of arsenic. PAGAN, E. N. (34) WHAT IS TEE BEST WAY TO REMOVE SPP-^Y ST JLHS TBOk *PPLES. Perm. State Hort. Assoc. ?roc. 1923, 54th *zir.. Meeting, p. 41. • The perfect icn of spreaders and sticliers may mean the carrying of more spray material on the fruit into the market, Th^re may be objections to this from the point of view of public health. The author believes anyone would die from the effects of over-eating before they got enough arsenic to hurt them, ^ome growers brush or wipe tne fruit to remove the spray stain: . . -11- FELLEEIEEG , T. VON (35) feSR DEN ARSENGlKAIffl NATURLI CBER USD MIT ARSiTKPRAPARATEiJ . BEEA1IDELTER LSBENSMITTEL. Biochem. Ztschr. 218; 500-317. 1930. The author's results indicate that fruits sprayed with arsenic could scarcely c^use arsenic poisoning. On . the other hand, lead arsenate should be discarded because of its lead content and should be replaced by other arsenic preparations, such as calcium arsenate. FERNALD, C. E. (36) [REPORT 07] DIVISION OP ENTOMOLOGY. Mass. [Batch] Agr. Expt. Sta. Bull. 2, pp. 3-1C. 1888. Prom 1 to 2 grains of arsenious acid will probably prove fatal to an aJLu.lt person. The fatal dose of paris green would be 2 to 3 tines that, and that of Tendon purple about the same a.s paris greca. Erne sis, followed by milk and eggs cr sugar a.nd magnesia in milk, is recommended for treatment of arsenical poisoning, FERBE, L. (37) LA NICOTINE EN VITICULTURE. Ann. Ealsif. 23; 337-344. 1930. Rev. Vit. 73: 173-134. 1930. The use of nicotine in viticulture presents no inconvenience since it is always completely eliminated no matter what the atmospheric conditions may oe. In rainy years it is carried off because of its solubility in water. In dry, warm years it volatilizes. The same cannot be said of the arsenicals usually employed. PI SEER, D. P. (33) RECENT DEVELOPMENTS IN SPRAY RESIDUE REMOVAL. Jour. Econ. Ent. 24: 526-529. 1931. The psychological aspects of spray residue removal, rather than attendant technical difficulties, a„re the factors which need greatest emphasis at the present time. FRANCOIS, L. (39) LES COMPOSES DE L 'ARSENIC ET LA DESTRUCTION DE5 PARASITES. Rev. Chim. Indus. 23: 124-131. 1912. The use of arsenical insecticides on grape vines and fruit trees does not lead to dangerous' amounts of arsenic on the mature fruit or in wine or cider made from it. The absolute -12- interdiction oy the French Government of the use of arsenical s in agriculture is protested. GASMAN, H. (40) INSECIS INJURIOUS TO CABBAGE. Ky. Agr. Expt. Sta. Bui. 114. 17 pp. 1904. Two cases of illness .attributed to eating cabbage containing arsenical spray residue are reported. GATES, B. N. (41) SPRAYING VERSUS BEEKEEPING. Mass. State Bd. Agr. Apiary Insp. Bull. 10A. 22 pp. 1916. Reports are quoted and discussed from various parts of the country on poisoning of bees because of the applica- tion of insect icidal sprays to fruit trees while in blossom. GOSSARD, H. A. (42) IS SPRAYING DANGEROUS? Ohio Parmer 139 : 554. 1917. There is less danger to the consumers of sprayed products, on the average, than to the consumers of unsprayed fruits and vegetables which because of the presence of rots, fungous diseases, and accompanying deleterious products of decay, are a greater threat to human health than sprayed sound fruits and vegetables with scarcely more than a trace of poison on thorn. The author cannot recall a single proved case of death due to eating sprayed products. If products have been heavily sprayed with bordeaux mixture so that much adheres at harvest, washing with water with vinegar added will remove it. If an orchard were hea,vily sprayed at the sea„son when sucn crops as lettuce, spinach, beans, or heading cauliflower, growing between the rows, were about rea.dy for harvest, too much poison would lively adhere to the leaves. Spraying with arsena.te of lead can be performed on raspberries and black- berries until the most forward fruits are one-third to one- half grown. GWIN, C. M. (43) THE PAST AND PRESENT STATUS OP PLUCRINS CONTAINING INSECTICIDES. Jour. Econ. Ent. 26: 996-997. 1933. Daring 1932 there appeared several publications by Smyth and Lantz and oy Smyth, Lantz, and Smyth covering the chronic effects of fluorine. For a short time their data brought about a slight curtailment in research with the salts of fluorine as insecticides. -13- HARDING, T. S. ( 44 ) HOW MUCH POISON 6M WE EAT? Sci. Ainer. 149; 197-199. Illus. 1933, A popular discussion of the apray residue problem. "It is very strange aov/ some of us become frightened at shadows. Thousands become almost too scared to eat anything, while the fussy fanatics who write sensational books profit well in a monetary way and pose in self adulation as saviors of mankind and champions of the downtrodden public." HEARTY, E. i7. J. (45) ARSENIC SCARE Hi ENGLAND. N* Y. State Kort. Soc. Proc. 71: 201- 202. 1926. Because of illness alledgedly caused by eating apples containing an excess of arsenic, certain retailers were arrested in England for having on sale apples containing in excess of 0.01 grain of arsenic [ar sonic trioxide] per pound. Widespread publicity has made this matter a real issue. HECKS, G. H. (45) HOW CALIFORNIA WET SPRAY DILEMMA. Better Fruit 21 (7): 7. 1927. All fruit, including pears, shipped from California during the current year were wiped to remove arsenical residue. The incongruous situation in the United States Department of Agriculture, where the Bureau of Entomology has recommended the use of lead arsenate sprays for the codling moth and the Bureau of Chemistry has declared the fruit so treated to contain excessive lead and arsenic and to be deleterious to human health, is commented on. HENGL, F. , RECKENDORFER, R. , and BERAN, F. (47) DER aRSEN- UND BLEIGELaLT VON IRAUBEN, TRAUBSNMQST UND WE IN ALS FOLGE DER SCHA^LINGSSEKAkPFUNG. Gartenbauwiss. 4: 38-51. 1930. The amount of arsenic found on grapes five weeks after the last treatment with lead arsenate is so small that musts and wines prepared from them would cause no harm were it not for the presence of lead. Grapes for eating, taken from arsenic- treated vineyards, should, however, be washed. The amount of lead remaining on grapes five weeks after treatment is still so high that even a small amount could cause harm. The use of lead in bearing vineyards should be entirely forbidden. -14- HERMAN, P. A., and BRITTAIN, ff, H. (48) APPLE POLLINATION STUDIES. V. STUDIES IN BEE POISONING AS A. PHASE OP THE ORCHARD POLLINATION STUDIES. Canada Dept. Agr. Bull. 162: 158-193. 1933. Sprays and dusts containing arsenicals are dangerous to "bees when applied during "bloom. HILGENDORPF, G. , and BORCHERT , A. (49) UBER DIE EMPPINDLICHKEIT DER BISNEN GEGEN ARSENSTAUBEMITTEL. . Nachrichtenbl. deutschen Pflanzenschutzdienst 6: 37-38. 1926. Results show that the death of "bees and dusting with poisons are closely connected. HUTSON, R. (50) BEE INVESTIGATION. N. J. Agr. Expt. Sta. Ann. Rpt. 1923-1924, pp. 325-349. 1925. The "bees in a. certain apiary were very low in stores when the petal -fall spray was applied at the experiment station about three-eighths of a mile away, on May 20 and 21. On May 23 two hives of the "bees exhibited symptoms of "disappearing disease". Arsenic was found in excess of 0.0002 mg. per "bee. Subsequently, 500 mg. of arsenic trioxide was administered to a shook swarm which built combs from syrup containing the a,rsenic. Nothing happened, although 500 mg. is enough to kill 2,500,000 bees, a. number equal to 40 to 50 ordinary hives, supposing the minimum lethal dose for a bee wore 0.0002 mg. KALKUS, J. 7/. (51) ORCHARD HORSE DISEASE. Amer. Jour. Vet. M G d. 15: 139-144. 1920. A disea.se found in horses grazing in sprayed orchards or fed on orchard hay is described. Some authorities believe that this is due to lead arsenate poisoning. KALLET, A., and SCELINK, F. J. . (52) 100,000,000 GUINEA PIGS. 312pp. New York. 1933. Nation 135: 325-327. 1932. In chapter III, entitled "A steady diet of arsenic and lead", the danger to the public health of arsenic and lord residues on fruits and vegetables is discussed. The results of lead and arsenic analyses on American apples made by K. Lendrich are cited, as well as the findings of C. N. Myers and B. Throne as to the prevalence of arsenic poisoning and its sources. The U. S. Department of Agriculture is - 15 - criticized for .net . adopting a more aggressive policy toward tie • elimination of arsenic and lead spray residues. I3AOS, Hi G. H., and WALTON, C. L. (53) A NOTE 033 THE CONTROL OF TEE RASPBERRY BEETLE (BY TURUS TOMENTOSUS FARR.) BY iCBAH-S OF A BARIUM SILICOFLUORIDE .'..'ASH. Jour. Pomol. Hort. Sci. 11 (1): 77-80. 1933. Because of. the excessive poisonous residue remaining on raspberries treated with lead arsenate, experiment's nave been - made with various non-poisonous preparations. The. chronic toxicity to warm-blooded animals of barium silicofluoride is only one-twelfth that of lead arsenate and therefore the health hazard is probably- reduced to a negligible risk. l^SLlj ,VIN, "'., DYKE, ¥. H. , CHURCH, W. S., THORPE, T. E. , (54) 3GNS0R, RVC, and eHITSLEGGS, B. A. FINAL REPORT CF THE ROYAL COMMISSION APPOINTEE TO INQUIRE INTO ARSENICAL POISONING FROM THE CONSUMPTION OF BEER AND OTHER ARTICLES OF FOOD OR DFTNE. 52 pp. London. 1903. After an exhaustive inquiry into the subject of arsenical poisoning from beer or other articles of food or drink, it is recommended thH penalties be imposed upon the vendor of any food containing more than 1/100 grain of arsenic [i.e., arsenic trioxide] per gallon if liquid or more than l/lOO grain of arsenic per pound if solid. KRIEG (55) 3EITRAGS ZUR VERWENDUNG DES BLEIARSENIATS IN DEUTSCHLAND. Verh. Deut. gesell. Angew. Ent., 7. Mitglieder.versamnil. Munchen, 31. Mai bis 2. -Juni , 1926. pp. 101-103. 1929. In spite of the widespread use of lead arsenate abroad [i.e., outside of Germany], illnesses therefrom rem-:. in almost unknown. When England. undertakes an investigation of the lead [?] on imported fruit ,: it is done as an economic . protective measure for the fruit growers of England and her dominions. The hygienic considerations are only a pretext. KUHN, H. A. (56) TEE' PROBLEM OF ARSENICAL RESIDUES: IMPORTANCE OF SPRkY DEPOSITS FROM THE STANDPOINT OF PUBLIC HEALTH. 4th Intornat. Congr. Ent., Ithaca, Aug. 1926. Vol. II, Trans., pp. 673-674. 1929. Only an abstract of the address is given. The minimum lethal dose of a number of insecticides, including arsenious oxide, calcium - 16 - arsenate, lead arsenate, barium fluoride, and sodium fluosilicate, ad- ministered "by mouth to warm-blooded animals, was determinedi The re- sults obtained were; arsenious oxide, particle size 10.5 mu, 20 mg» per kg. body weight for rabbits and 85 mg. per kg. for dogs; calcium arsenite (consisting of 46,8 percent calcium arsenite, 6.8 percent calcium arsenate and 45.8 percent arsenious oxide), 8 mg. per kg, body weight for dogs; calcium arsenate (70.5 percent Ca„(As0 4 ) ? with an excess of calcium oxide and approximately 0.2 percent water- roIudIo arsenic calculated as AS2O5) , ■ 38 mg, per kg. for dogs and 50 mg. per kg, for rabbits; commercial lead arsenate, chiefly PbHAsO., 500 mg, per kg, for dogs; sodium fluosilicate (74.2 percent HagSiFg), 138 mg. per kg. for rabbits and 150 mg. per kg. for dogs; barium fluoride (99.1 percent BaFg), 200 mg. per kg, for rabbits and 550 ng. per kg, for dogs. All of the arsenical compounds produced gastro-intestinal irrita- tion and the symptoms and pathological findings were those of acute arsenical poisoning. The principal symptoms observed in the case of the fluorides were those of acute irritation with hemorrhages in the stomach mucor.fi and intestines. The principal organs affected were the liver and kidneys. The toxicity of calcium arsenite when given by mouth is very close to th,-t of arsenious oxide when administered intravenously. The effect of sublethal doses of calcium arsenate may be chronic arsenical poisoning. The principal effect of small doses of fluoride will be loss of appetite, disturbance of digestion, and of calcium balance. In order to study the cumulative effect of sublethal doses of lead arsenate, 4 dogs were given l/25 of the lethal dose by mouth each 48 hours The first dog died after receiving 5/25 of the minimum lethal dose, the second after ll/25, the third after 20/25, and the fourth after 23/25. All of the dogs developed anemia, bloody diarrhea, and after the fourth dose showed salivation and nasal discharge such as are usually found in subacute arsenical poisoning. The drop in the red blood count was about 30 percent. The principa organs were analyzed for lead and arsenic. The lead to arsenic ratio in the dog dying after 47 days is of particular interest. In the original compound the ratio of arsenic to lead was 1:3.85. At death it was found to be 1:39.5 in the liver, 1:19.1 in the kidneys, 1:8.9 in the leg bones,, and 1:5.6 in the spleen. Apparently the lead was being retained while the arsenic was eliminated. It is evident that acute deaths from lead arsenate are due essen- tially to arsenic while in chronic poisoning the symptoms are due princi- pally to lead. In investigating the spray residue on fruit sprayed with lead arsenate, both the arsenic and lead should be determined. The small amount of arsenic in a spray residue will probably do less harm than the lead, due to a very slow elimination of the latter. - 17 - LARISOF, C. H. , FICHOLS, H. E. , CARTER, E. A., and WILLIAMS, C. (57) REPORT OF RESOLUTIONS COLhlTTEE (PERTAIFIFG TO SPRAY RESIDUE). Iowa State Hort. Soc. Trans. 67: 105-108. 1932. The darger of arsenical insecticides from the standpoint of health is discussed. Dr. Binford Throne is quoted as saying that "arsenic even in smaller amounts than the legal tolerance is a menace tq public health and. from a regulative point of view the limit set is r .'j surd . " LEDOUX, E. (58) ITTOXICATIOF X.RSFFICALE FAKILIAIE PAR LE VIF DS RAISIFS TRAITE*S PAR DES INSECTICIDES A BASE D'^RSEFIATE DE PLOHB. Bui. ct Mem. Soc. Med. Eopitaux de Paris (3) 50: 1566-1567. 1926. Five members of a family were poisoned "by drinking wine contain- ing arsenic due to insecticidal treatment cf the grapes. LEHLIAFF, H. (59) DIE AFSEFFRaGE. Schweiz. Obst. u. Gartenbau-Ztg. 1923 (19): 320- 322. 1923. [Abstract in Rev. Appl. Ent. (A) 12: 45. 1924.] The results from numerous experiments to determine the residual quantities' of arsenic after spraying are tabulated, and the conclusion is reached that no fear need be entertained of poisoning from this cause. LEFDRICE, K., and MAYER, F. (60) USER DAS V0BK0I.2JBIT VOF ARSEF UFD BLSI AUF OBST ALS FOLGE DER SCFAELIilGSBEFAI/lPFLrhG. Ztschr. Untersuch. Lebensmtl. 52: 441- 457. 1926. Tests for arsenic and lead were made on fresh fruits, dried fruits, and preserves. The preserves, of American origin., 7/erc free fro;-! arsenic and lead. The maximum amount of arsenic found in dried apples was 0.015 rig. of arsenic tri oxide in 100 g. Fifteen tests were made on fresh apples from the United States, Canada, and Australia.. Uith one exception, all samples contained arsenic and 10 contained lead also. The amounts of arsenic tri- ■ oxide in the test samples of 2 or 3 apples wore: pulp to 0.029 mg. , peel to 2.32 mg, , blossom and stem ends to 2.75 mg. The maximum quantities of lead were : peel 3.64 mg. , whole apple 7.45 mg. (in 435 g. of apples). Washing the apples removes some, but not all, of the arsenic and lead. Although in general there may appear to be no direct danger to human health from the amounts of lead and arsenic on fre.it which has received insecticido.1 treatments, yet in some cases anounts have bc^n foiind which cannot be considered harmless. - 18 - The occurrence of lead- with arsenic seems especially risky since the forcer is not eliminated from the human organism as arsenic is. It would not he practicable to try to control the amount on fruits nor to forbid the use of lead and arsenic containing insecticides until a harmless substitute is found, peeling can apply only to apples and pears and not to other sorts of fruit which are similarly sprayed, and washing will not be satisfactory in all circumstances. We would see an improvement if lead were cut out of the sprays and spraying of fruit trees and bushes was undertaken only once shortly after blooming. The elimination of lead seems possible since calcium arsenate is as active as lead arsenate in insect control. Furthermore the single spraying would bring about a narked decrease in the amount of arsenic on the fruit. LEONARD, -7. V. . (61) REMOVAL OF SPRAY RESIDUE. Idaho State Hort. Assoc. Proc. 37: 90. 1932. "I don't know whether to talk much on residue, or the poison from arsenical residue, or about the health from eating apples in our state. There have been no deaths at all from it." LUTJE (62) IJASSELEMRAKXUNGEH UHTSR WEIEETIEEEE I1T 03STH0FEN EACH DER VEHHEKDOHG VON KUPFFEKALKBBDHE ZUR 05STSCHADLINGSBEKAMPFUNG-. Nachrichtenbl. Deutsch. Pflanzonschutzdienst 9: 1-3. 1929. Rev. Appl. Mycol. 8: 386. In 3.927, 26 sheep, and in 1928, 274 sheep, 6 cows, and a calf were stricken with copper poisoning after grazing in orchards where copper sulfate had previously been used for pest control. McCLUHD, F. J., and MITCHELL, H. k. (63) THE EFFECT CF FLUORINE OH THE CALCIUM METABOLISLi OF ALBINO RATS AND THE COMPOSITION OF THE BOSSES. Jour. Biol. Chen. 90: 297-320. 1931. Fluorine, especially when consumed in the form of the soluble sodium salt, may cause the deposition of an apparently abnormal constituent in the bones, or an abnormal deposition of a non-calcium constituent, possibly a fluoride of a mineral other than calcium, as evidenced by an increase in the percentage of ash in the bones above the normal. There is also an interference with the deposition of calcium in the bones brought about by feeding fluorine. - 19 - McCUTCHBOi!, A. (54) ■A2S3HIC; UITK SP3CIAL ESISCTC3 TO ITS USB IK HORTICULTUR3 ABB AGRICULTURE. . Phr.rn. Jour. 116: 109-112; Chen & Druggist 104: 151. 1926. The danger involved in eating arscnically treated fruits is mentioned. McIBBOO, H. 3., and DEHUTH, G. S. (C5) EFFECTS 01;' HOEEYBEES OF SPRAYIEG FRUIT THE3S WITH ARSENICALS. ' U. S. Dept. Agr. Bull. 1364. 32 pp, 1926. The nininun fatal dosage of arsenic (As^Or?) for a bee is about 0.0004 or 0.0005 ng. Bees poisoned when working in sprayed orchards obtained most of the arsenic from the pollen. I'/iAHTHLY, p. (65) U3B3B BIB GEFAHEEH BER AKSSHDU1TG ARS3NHALTIGER i/IITTEL GEG3N SCBElDLIiTGE . Ztschr. Desinfekt. Gesundhtsw. 23: 245-268. 1931. The danger, fro: 1 , the standpoint of health, of the use of arsenical agents for pest coi'trol in orchards, vegetable gardens, vineyards, etc., is emphasized. A lengthy bibliography is appended. MARCOVITCH, S. (67) STUDIES OH TOXICITY OF FLUOBIBE COMPOUNDS, Tenn. Agr. Sxpt, Sta. Bull. 139. 48 pp., illus. 1928. The minimum lethal doses by mouth for nan, based on the values found for hannals, arc: sodium fluoride 30 g. , sodium fluosilicate 7.2 g. , potassium arsenite 0.84 g. (68) TE2 EI SI BUB PROBLEli ABB FLUORIHE COiiPOUNDS. Jour. Scon. Bnt. 25: 141-142. 1932. Of prine concern fro:: the standpoint of public health is the possible chronic rather than acute action of fluorine on the system, as compared with arsenic. Data arc quoted which show that both fluorine compounds and arsenical s have high acute toxic values. As to chronic toxicity, the fluorine compounds are at least 100,000 times safer than lead arsenate and possess a marginal safety factor over the average spray residue content of 75. - 20 - MELAIEER, A. L. (69) CONSIDER BEES UHSIT SPIUYIUG. Uash. State Coll. Znt. Ext. Circ. 13. 2pp. [Him. n. d.J- Better Fruit 13 (9): 36. 1919. Fruit trees in blossom should not "be sprayed, and ex- cessive spray that drips on alfalfa or vetch "beneath should not "be applied. These measures are recommended to safeguard the bees. kTJTTELET, C.-F. (70) L'ARSSITIATE 2E PL0I.13 SIT VITICULTURE. Ann. Falsif . 9: 298-301. 1916. The wines and "-piquettes" do not contain poisonous metals (lead, arsenic, copper) when they are carefully freed from the lees, but the latter contain a notable proportion of lead, and consumption of the above products before deposition of the Ices presents a certain danger. It seems, therefore, that an intensive arsenical treatment prolonged after the formation of the fruits docs not introc ace poisonous metals into products carefully prepared for consumption. (71) L'ARSSHIATE IE PL01I3 SIC VITICULTURE. Rev. Vitic. 46: 215-217. 1917. Intensive arsenical treatment of grape vines, prolonged after, the formation of the berries, docs not introduce toxic metals (lead, arsenic or copper) into wines which are carefully prepared. The leer, and marc retain them. MUTTEL2T, F. , and TOUPLAIIT, F. (72) L'ARSEITIATS IE PL0..3 EH VITICULTURE. Ann. Falsif. 5: 9-16. 1912. The grapes, marcs, wines, "piquettes" and lees from vines treated with lead arsenate do not differ in arsenic content from the products obtained from untreated vines. The wines and "piquettes" do not contain load. The lees in certain cases contain a notable proportion of lead, and consumption of the wine or the "piquet to" before deposition of the lees would present a certain danger. The grapes may sometimes retain sufficient lead to make their consumption dangerous. MYERS, C. IT. , TBBOHE, 3., GU3TAFS0IT, P. , and KIHGSBUEG, J. (73) SIGNIFICANCE AITD EAITGZR OF SPRAY RESIDUE, Indus, and Engin. Chen. 25: 624-623. 1933. Metals play a part in the production of certain well- defined clinical symptoms, such as the development of bald snots. Tables arc presented indicating that there is a seasonal - 21 - and geographic variation in the arsenic and lead content of fruits, vegetables, and canned goods. It is appo.rent that the present methods of washing and removing spray residues are inefficient and inexact. This is particularly time in the care of lead. The present spray residue situation constitutes a menace to the general well-being cf the public, and the tine must come when every individua] State will be rilling to take a part in the regulatory procedure. ---, VAK DYCK, L. , and 3HB0NE, 3. (74) ARSESTC AS A paOBIEii IE PIESE17T DAI FOLIC HEALTH MAEAGEM3ET. Led. Times 57: 134-142. 1929. The occurrence of arsenic on fruit, due to treatment with insecticides, in amounts ^-r to 1/10 grain of arsenic trioxide per Doun^, is reported. The authors contend that arsenic in even smaller amounts than the legal tolerance is a menace to public health. Fruits, vegetables, and food should be free from metallic contaminations, and the use of insecticides containing copper, lead, or arsenic should be abolished. NBLSON, I. Li. , ITORD-KA3ESR, A. h. , ana E03IES0IT, W. 0. (75) SEDCKIUH AS AN IESECTICiUS. Science 78: 174. 1933. Selenium in the soil is lilated by some plants, rendering them toxic. Ordinarily innocuous spray residues containing selenium might also be absorbed by the plantc and converted into highly toxic combinations. HEWTOK, J. E. (76) TEE AL3ALFA WEEVIL IS C0L0EAL0. Colo. Agr. Expt. Sta. hull. 399. 19 pp. , illus. 1933. Spraying the tips of alfalfa plants with an arsenical, such .as load arsenate, calcium arsenate or zinc arson! to, is recommended for the control of the alfalfa weevil, Eypera p osticus Gyll. Properly sprayed hay (e. g. , 2 lbs. cf calcium arsenate or 2.5 lbs, of zinc arsenite per acre) does not contain sufficient arsenic to made it unsafe for stock food. O'KAKE, 17. C, BALL, E. P., DAVIS, J. J., HEADLS3, T. J., (77) and ESSIC, E. 0. SUPPLEMENT TO PROGRESS REPORT 0E CChhlhJEE TO INVESTIGATE ARSENICAL RESIDUES CI FRUITS AS THE RESULT OP SPRAY PEOGRAMS. Jour. Econ. Ent. 20: 31-35. 1927. It is ra#o:amended that the U. S. Department of Agriculture call in conference representatives of the American Medical Association, a physiological laboratory such as that of Chicago University, interested State erperimcnt stations, a x id others, together with experts in the Department, to plan a joint inves- tigation that will disclose the "basic facts with reference to tolerance and that the Department of Agriculture and the State experiment station:-, ^'ve special attention to new agents for control of injuriors insects and to control measures other than application of sprats. — , HADLEY, C. H. , Jr., and OSGOOD, W. A. (79) AHSEiJlCAL HZ SI DDES AFTSH SPFAi'IKS. E. E. Agr. Sxpt. Sta. Ball. 183. 62 pp. 1917. "This bulletin give 3 the results of experiirents "begun in 1j12 and concluded in 1516, intended to provide further data as to the amounts of arsenical residues rorair.ing on fruits and vegetables, a^ter spraying with arsenate of lead, the toxic prop- erties of arsenate of lead, and the possibility of serious poison- ing of live steel; pastured, on forage containing residues of arsen- ate of lead." "The amounts ef arsenic adhering to apples, strawberries, cixrrants, blackberries, cabbages, and lettuce after spraying with load arsenate (3 lb 3. 01 paste to 50 gals, of water) were deter- mined experimentally. The maximum amount that wo old adhere to apples direct ly sprayed was 4 mg. of arserie triox H de per fruit. The other fruits and vegetables were sprayed end part of each picked before and the rest a.ftcr rainfall had occurred. The amounts of arsenic tri oxide were in the following ranges; strawoerrics 8.6 to 54.2 mg. per qt.; currant*^ 6.8 to 10.2 rag. per qt.; black- berries 3.8 to 11.2 mg. per qt.; cabbage 43.5 to 51.4 mg. per head (including outer leaves); lettuce 1.6 to 10,6 mg. per head (includ- ing outer leaves). The amount on apples ordinarily s;orayed would, probably not exceed 0.5 mg. per fruit. The solubility of lead arsenate in human gastric jxiice was determined by A. J. Carlson and A. Woelfel. Aoout 5 percent of the arsenates of lead dissolve in human gastric juice when nixed in the proportion of 0.5 grain lead arsenate to 25 cc. of the juice. Apple pulp increases the solubility but ailk practically prevents solution. Feeding experiments were also carried out on guinea pigs. From the results of all this work the authors conclude "that under ordinary conditions no apples will reach the consumer carry- ing such amounts of lead arsenate per fruit that a healthy human adult can eat enough at one tine to cause fatal poisoning. Straw- berries that are fully formed should not be directly sprayed with lead arsenate, unless they a.re to be scrubbed before using. Blexx- berries should not be directly sprayed after the berries are formed. Currants, if so sprayed, should be washed. With cabbage and lettuce ready for market arsenate of lead should not be applied except sparingly, and in that event the outer leaves should be removed end the heads should be washed. The case is not clear as to - 23 - possible injurious effects from long-continued daily consumption of fruits carrying relatively small residues, "but it is believed that the use of apples from trees sprayed w ith load arsenate, at • the rate of 3 lbs, of the paste to 50 gallons of water, offers very slight danger, if any, this danger being negligible in the case of winter fruit sprayed two months or more prior to harvest* Early fruit sprayed just before harvest should be wiped." Experiments appear tc indicate that health" calves may be pastured for a period ot^ gra?s carrying considerable spray when the strength of solution used ir 3 lb"-, lead arsenate pe,ste to 50 gals, of water. At a cor cent ration of 6 lbs. to 50 gals, con- tinued feeding may result ir definite and serious symptoms of poisoning, while at l n lbs. to 50 gals, sericus or fatal poisoning is likely to occur. Approximately the same results were obtained with sheep, although .hey were romownat rorc resistant. There is very little danger cf poisoning to chicxs or hens eating grass en which lead arsenate spray has dropped. Chickens are apparently not especially susceptible to load arsenate poisoning, PAIGE, J. B. (79) CASSIS P0IS0KI2G ERCi: ARSENATE CF LEAD. Mass. Agr. Expt. Sta. Ann. Rot. 31: 133-199. 1909. The amount of hay obtained from under a medium sized tree was found to be oO lbs. Allowing for a drip of 1 gal, in 10 of a spray mixture of 10 lbs. of lead arsenate in 100 gals* of water, each 10 lbs. of hay would carry 9.06 grans of lead arsenate paste or about half that amount cf dry arsenate. The results of experiments conducted by the author en the toxicity of lead arsenate to cattle indicate that a 10 pound feeding of such hay would hardly produce serious effects but continuous feeding of it for several days in succession certainly would do so and animals would probably n -a.t sufficient to cause fatal poisoning. P [ APICES] , T. (80) AR3E1TIC Oh" APPLES. Bull. Chamber Ear t. [London] 3 (l); 11-13. 1926. [Abstract in Rev. Appl. 3nt. (A) 14: 218. 1926.] Recent examination has shown that while English apples bear only negligible traces cf arsenic on their skins, imported fruit bears arsenic slightly in excess of 0.01 grain per pound. It has recently been suggested, and unfortunately definitely stated in the press, that arsenic is present in the flesh of tne apple and that neither washing nor peeling will eompletely eliminate it. It is true that arsenic in very minute doses may be taken up by the roots of the fruit tree in the nutrient solution, but there should be no danger whatever of such contamination ever being sufficiently concentrated /to constitute a danger to health. Pastors influencing the adhesiveness of arsenicals to sprayed - 24 - fruit?" and the amount of deposit remaining on the fruit ore the use of a spreader or adhesive substance in the spray, the physical properties of '.he spray (fineness of subdivision), and the extent of rainfall immediately following spraying operations. If a heavy shower occurs' shortly after an application of lead arsenate and caseinate, much of the poison will be washed off, but if there is no rain for a day or two, the poison will' have adhered firmly and subsequent washing will have little effect. If an apple contaminated with this deposit be washed with water, the deposit is very difficult to remove, vigorous polishing being necessary to make any impression. The question of eliminating this da±iger or reducing it to negligible quantities is a serious one. One measure to be considered is wiping the fruit before packing, but this would prove rather costly. The use of less po5 sonous in- secticides has been investigated, but there are very few materials that are likely to form a suitable substitute for arsenicals. The possibility of attacking Carpocapsa pomonella at some other stage than the larval requires investigation. Close inspection and analysis at the port of entry might be arranged by. the Ministries- of Agriculture and Health and the port medica]. authorities. POROUS T (81) LES TRAITEMENTS CULTUMUX AUX SEES WASSSS1G IT L' HYGIENE ALIMSNTAIRE. Hyg. Bur. Sanit. Fed. 48: 79-83. 1910. Schweiz. TJchnschr. Chem. u. P*i&rra, 48: 694-696, 1910. Analyses for arsenic on fruits treated with arsenical insectides and on untreated fruits indicates that the rational use oi' such insecticides at the prescribed time, not later than one week after blossoming, presents no danger to the consumer. Late applications may cause serious accidents. PORTER, 3. A., QUA.INTANCS, A. L. , DEAN, 0. A. FLINT, ¥. P., (82) FARR0T2, p. J t , and CHILES, C. REPORT OP COMMITTEE TO FOSL-IULATS PLANS FOR INVESTIGATIONS OF THE CODLING- MOTH FROM EIOLOGIC AND CONTROL STANDPOINTS. Jour. Econ. Ent. 21 j 31-38. 192c'.. The results of experiments looking to the avoidance of excessive spray residue are reported. Dusted fruit carries residues well under 0.01 grain per pound. Before any possible substitute for arsenate of lead can come into commercial use, it will be necessary to determine the margin which may exist between the amount of residue the substitute leaves under various con- ditions and the quantity of substitute which is likely to be considered deleterious to human health. ~ 25 - POTTS, 3. C. (83) ISSIDUE I.IUST GO, SAYS G0VERPM31TT. Bettor Fruit 22 (l) : 724. 1327. An editorial. l "7. G. Campbell is quoted as saying that the question is not whether perfect solvent and removal devices have oeen evolved but whether fruit safe for consumption is turned out. S. Smith, United States marketing agent in Europe, is also quoted, showing the grave danger to the trade of American apple exports "because of spray residues on fruit exported. PRICE, ". A. (-84) PELS AiTD TE3IR PSLATIOIT TO APSEITICAL SPPAYS AT BLOSSOKIEG TILS. Ind. Agr. Expt. Sta. Bull. 247. 15 pp. 3.920. The Gutzeit method of determination of arsenic appears to "be sensitive enough for most doses that kill Toees, although some very sma.ll fatal doses may escape detection. Less than 0,0000005 g. [0.5 microgram] of arsenic trioxide is a fatal dose for a "bee. Bees work freely on sprayed trees in the open even when there are unsprayed trees all about. Por the sake of the bee, fruit trees should not be sprayed while in full bloom. REES, H. L. (85) DA1TC-EP FBOM LEAD ARSENATE POI S01TII7G. Wash. Agr. Expt. Sta. Mo. Bull. 2 (7): 11. 1914. The autnor quotes evidence from several sources to show that fears of eating sprayed vegetables and fruits are groundless. PEEVES, G. I. (86) TEE APSEl'ICAL POISOIIIITG OP LIVE- STOCK. Jour. Ec on. Ent. 18 (1): 83-89. 1925. Pe commendations for the spraying of lucerne to control the alfalfa weevil, H ype ra (Phytonomus ) miirina P., have been guided largely by the work of Dr. E. C. Gardiner on the a-rsenical poisoning of domestic animals. It deals \vith the tolerance of farm animals for arsenic and describes the symptoms of arsenical poisoning and the lesions produced b Tr it. It was proved that horses and cattle can take from 20 to 30 grains of arsenic daily, for an indefinite period, without any external evidence of injury or any alteration discernible upon post-mortem examination. Sheep arc more easily poisoned, requiring only 4 to 8 grains daily. The fatal dose for horses and cows is 300 grains. The dangerous dose is shown to be far greater than the amount that is contained in a feed of sprayed hay. - 26 - ROARK, R. C. (87) I17SSCTICIDES STUDIED TO INCREASE EFFECTIVENESS AED DETSRmIHE CHEAPER METHODS 01 IlAMJEACi'UHE. U. S. Daily, April 25, 1928. "Latoly heal tli officials have objected to the apparently excessive quantities of arsenic and lead upon apples and other f raits and vegetables which have been sprayed with arsenical insecticides. Arsenic and lead are recognized as deleterious substances, ana" the physician oroperly objects to more than traces of these, particularly Irad, in f oodstuff s. " (88) CHEMICALLY COIiBATIEG Il/SECT PESTS OF FOODSTUFFS. Indus, and Engin. Chen. 24: 646-648. 1932. On account of the volatility of free nicotine and the ready solubility of b^th nicotine and nicotine sulphate in water, fruits and vegetables rarely have on then detectable quantities of nicotine. Cases are on record, however, of persons suffering iron nicotine poisoning duo to eating lettuce from a greenhouse where nicotine had been- recently sprayed. The use of arsenical compounds, on fruits and vegetables causes much concern because of the arsenical residue left. Apple growers have been compelled to wash the fruit is dilute acid or alkaline solutions. Efforts to find a substitute for lead arsenate for codling moth control have been under way for many years. Certain fluorine compounds have shown the most oronisc of any materials of inorganic origin. The question of tolerance for fluorine remains to be determined. B0BII7S0IT, D. H. (89) ARSEITIC II! APPLES. Fertiliser, Fee ding- Stuffs and Farm Supplies Jour. 11: 600-601. 1926* Th^rc is no danger of arsenic in English-grown apples, as one spray of lead arsenate, ic sufficient to control the codling moth in that country. In America repeated spraying is necessary. Samples of foreign apjples, mostly American, contained as much as l/30 to l/lO yrain of arsenic (AS2O3) per pound. The risk of death or serious poi soring fro:: arsonic in any apples is considerably less than that incurred ill crossing a busy city street. ROTHPLETZ, F. J. (90) SODIUM FLUORIDE A SAFE INSECTICIDE WHEE PROPERLY USED. Prog. Farming (?) 35: 1197. 1920. - 27 - ROUGIER, L. (91). AU SjJET LES INSECTICIDES EI AETICFYPTOGAMIQUES ET DES DANGERS QU' ILS PRESENTEN1. Progr. Agr. et .Title. 97: 422-425. 1930. Sheep fed for a. period of a month on green clover soaked in bordeaux mixture showed no signs of ill effects, and chemical examination of the flesh and other tissues of one of the sheep revealed no copper. RUEDIGER, E. (92) SCEADLINGSBEOMFEUNG L'lT ARSEN. Int. Rdsch. 48: 11-14. 1931. The dangers in using arsenical dusts for pest control are emphasized. SCHULZ, 3. P., and THOMPSON, 17. P. (93) SOLS EFFECTS OF SODIUM AESENITE 'THEN USEE TO EI LI THE- COMMON BARBERRY. U. S. Dept. Agr. Bull. 1316. 13 pp. 1925. In using arsenic in hulling weeds, its extreme toxicity to animals must he considered. Cattle are attracted by the taste of arsenic. Repellents, such as aloes, have been used with success. SCHULZ, J. A., and LAMB, A. p. (94) THE EFFECT OF FLUORINE AS SODIUM FLUORIDE ON THE GROWTH AND REPRODUCTION OF ALBINO RATS. Science [n. s.] 61: 93-94. 1925. No ill effects on growth and well-being are observed until 0.10 percent of sodium fluoride is fed in the ration of the rats. A very narked toxic effect is observed when 0.15 to 0.25 percent is fed. Apparently an unfavorable effect on reproduction begins at a level of about 0.025 percent sodium fluoride. The fluorine caused, abnormal growth of the upper incisors of the rats. SMITE, U. C, and LEvEHTON, R. II. (95) COMPARATIVE TOXICITY OF FLUORINE COMPOUNDS. Indus, and Engin. Chen. 26: 791-797. 1934. The toxicity to young albino rats of sodium, potassium, ammonium, and calcium fluorides, sodium, potassium, and barium fluosilicates, and natural cryolite (sodium aluminum fluoride) was studied. Cryolite and calcium fluoride, the least soluble of these compounds, were many tines less toxic than the other, more soluble compounds from the standpoint of their effect upon growth rate and food utilization and. of the amount necessary to cause death. Fluorine Interfered with the normal process of reproduction only at those levels of feeding which resulted in stunting in growth - 28 - of the female. Concentrations fir "below these accessary to interfere with growth or general health caused damage to the incisor teeth. Much L.ore of the cryolite ar.d calcium fluoride than of tne other com- pounds was required to cause ccrrosicn and pitting of the enamel, but all of the compounds of fluorine studied left a mark characterized by the appearance of fine, lighter pigment lines on the incisor teeth when incorporated in thg diet (for 6 weeks) at a C.0C14 percent (fluorine) level (14 p. p.m.) or fed separately in daily doses of 0.2 rag. fluorine to young rets or fed at the levul of 1 mg. per kg. of body weight. SMCT, H. F., and SMYTH, H. ?., JH. (96) RELATIVE TOXICITY OF SOME FLUOEINF AIT AR3EMCAL INSECTICIDES. Indus, and Engin. Chem. 24: 229-232. 1932. The relative toxicity of fluorine and arsenical insecticides was determined "by feeding to white rata various accurately measured amounts of cryolite, "barium fltso silicate, and lead arsenate mixed with their food for 16 weeks. The results, including behavior, appetite, fecundity, growth, tooth 4©*#lopai©n$ , and organ path- ology, agree in indicating the arsenical compound to "be several times as toxic as the fluorine compounds. SOLLMAN, T., SCHETTLER, 0. H. , and WETZEL, N. C. (97) STUDIES OF CHRONIC I FT OX I CAT I CMS ON ALBINO BATS IV. FLUORID, CHLOFID AND CALCIUM (INCLUDING- SODIUM ILUORID, SODIUM CHLOFID, "PHOSPHATE ROCK", CALCIUM PHOSFKATE (PRECIPITATED) AND CALCIUM CARBONAIS (PRECIPITATED). Jour. Pharmacol, and Erpt. Ther. 17: 197-225. 1921. Sodium fluoride eaten with food during long periods in daily doses of 15 to 150 mg. per kg. of "body weight results in progressive impairment of growth and. food consumption. The damage is proportional to the dose. It tends to outlast the administration of the drug, so that the growth of animals that have been poisoned with fluoride remains permanently below that of unpoisoned animals. No deleterious . effects on growth or food consumption occurred in 9 weeks with daily- doses' of" sodium fluoride of 8 mg. per kg. of body weight »r less. STEINSR, L. F.; ACKERMAN, A. J., and HAMILTON, D. W. (98)' THE VALUE OF SUPPLEMENTARY MEASURES IN TNE CODLING MOTH CONTROL PRCGPuM. Ind. Hort. Soc. Trans. 1934: 34-40. 1935. The point has "been reached in the application of lead arsenate for codling moth control "here the poison needed to control the pest is not only dangerous to humans if it cannot he removed at harvest time, but is injurious to the tree itself. T., P. E. (99) SPRAY POISONING. Wash. Farmer 42 (6): 13. 1919. - 29 - 2ALB3RT, T. J., and TAYLOE, 7. L. (100) NEW LIGHT ON THE SPRAY RESIDUE PROBLEM.. Amer. Fruit Grower 51 (2): 5-7, illus. 1931. [Also in Amer. Soc . H rt. Sci. Proc. 1930; 538-542. 1931.] From the results of their tests on rats, the authors conclude that a man would have to consume at one time 100 pounds of fruit containing 0.02 grain of arsenious oxide per pound to cause any harmful effects. AITD TAYLOE, 7. L. (101) SOIIE RESULTS FRO!.: FEEDING SPRAY CHEMICALS TO ALBINO RATS. Ho. Agr. Expt. Sta. Res. Bull. 163. 19 pp., illus. 1933. "Arsenic as arsenic trioxidc or in combination with the lead in the form of commercial lead arsenate, or with calcium arsenate and lead acetate, appears to affect albino rats as follows: "Arsenic salts in quantities ranging from the equivalent of four times to two hundred times the official world tolerance may promote activity and growth in the original stock for the first twenty-three to twenty-five weeks. "Dosage of insecticides continued for periods of more than fifteen weeks decrease the ability to raise young in the first generation. "Arsenic did not appear to retard growth unless fed in quantities larger than the equivalent of 0.04 grain arsenic trioxide per pound of fruit. "L^ad as lead acetate and arsenic in its various forms as an insecticide appear to have injurious effects on albino rats only after prolonged feeding. "Arsenic or lead, or both, when fed in quantities larger than the equivalent to 0,04 grain for about 175 days, seemed to have an in- jurious effect on the offspring by decreasing the weight and the ability of the females to produce and rear young, "TThen spray chemicals are fed daily tver long periods in quanti- ties equivalent to more than four times the world tolerance, they have very marked injurious effects on albino rats, and ••'hen the feeding is extended for four hundred days or more, the mortality rate increased and amounted to as much as 35.4 percent. "Contrary to general opinion, the spray insecticides do not have as acute toxic effects on albino rats as is generally supposed, even when used in amounts of two hundred times the official world tolerance. LIBRARY STATE PLANT BOARD - 30 - "Our experience indicates that the arsenicals in fruit sprays have in fact, acute stimulating effects- and injurious effects are "brought on .only when feeding is regular and prolonged, -as shown "in -the feeding periods ranging from 378 to 497 days. "If it may "be assumed that the spray chemicals have an effect upon man similar to that which they have upon albino rats, it is the opinion of the authors that there is little likelihood of a human consuming as spray residue on apples, sprayed and" handled in the usual manner, enough arsenic either at one time or over an extended period to be injurious. In view of the varying effects of lead poisoning given in the literature, the tests made in this experiment do not appear adequate to justify the drawing of conclusions as to the risk of lead poisoning from the consumption of sprayed' apples." (Authors' abstract.) THOMAS, E. 3T., and SHEALY , A. L. (102) LEAD ARSENATE POISONING IN CHICKENS. Jour. Agr . Research 45: 317-319. 1932. During the spring of 1929, numerous complaints were received from poultry owners in areas of -Florida where lead arsenate spray was being used in combating the Mediterranean fruit fly. The spray formula used was: lead arsenate, 8 lbs.; brown sugar, 50 lbs.; syrup, 10 gals.; and water to make 200 gals. Approximately 7 gals, of this spray was used on an acre of citrus. The results of the experiments here reported indicate that 168 hens could consume this amount con- tinually for 60 days and suffer no ill effects. It would seem, there- fore, that it is impossible for chickens to consume enough solution or sprayed foliage in a sprayed grove to suffer from the effects of lead arsenate poisoning. TEOOP, J. (103) BLOSSOivi SPRAYING AND BEE POISONING. Jour. Econ. Ent. 11: 433. 1918. Experiments under way at the time of writing seem to indicate that bees may be killed by a poison spray at blossom time. VENXATAROYAN, S. V. (104) * ARE SPRAYED GRAPES POISONOUS? J ur. Mysore Agr. and Expt. Union 14 (1): 22-24. [n.d.] An adult can absorb daily for a period of weeks without ill effects from 0.2 to 0.5 g. of copper sulphate. Sprayed grapes on analysis have rarely been found to contain more than 5 mg. of copper per kg., the average being 2 l/2 to 3 mg. per kg. On this basis an adult may eat from 300 to 500 lbs. of sprayed grapes per day with- out fear of ill effects from copper. Allowing f»r the insolubility -31- of the copper in bordeaux mixture, this quantity is easily raised to 1,200 to 2,500 lbs. per day. Similarly, a man who drinks sprayed tea prepared in the ordinary manner does not exceed the limit of safety if he keeps himself within 10,000 large cups a day. WAKELAND, C. (105) SEASONAL VARIATION AS IT AFFECTS 'THE ACTIVITY AND CONTROL OF THE ALEALEA WJEVIL IN IDAHO.' Idaho Agr. Expt. Sta. Bull. 138. 11 pp. 1925. The preponderance of evidence is that there is no danger to livestock from eating hay properly sprayed with arsenicals. Two cases are cited which seem to indicate that under some conditions the presence of arsenic aggravates digestive or excretory disorders. WEBSTER, R. L., and CRE"'S, A. (106) SPRAY POISON IN THE YAKIMA VALLEY. Jour. Econ. Ent. 27: 614-617. 1934, Poisoning of bees by lead arsenate sprayed on fruit trees and potatoes is discussed. WILCOX, E. V. (107) APPLES AND ARSENIC. Country Cent. 91 (5): 21, 85, 86. 1926. Care in spraying ^vith arsenicals is urged to prevent the occurrence of excessive amounts of arsenical residue on apples. •■ WILLSON, R. B. (108) A POSSIBLE EEFECT ON FRUIT GROWING BY EXTENSIVE USE OF ARSENICAL DUSTS IN ORCHARD. N. Y. State Hort. Soc . Proc. 71st. Ann. Meeting, pp. 38-42. 1926. Poisoning of bees by arsenical dusts applied to orchards when flowers frequented by the bees were in bloom is reported. WILSON, H. F. (109) WILL FLUORINE COMPOUNDS BE ACCEPTED AS INSECTICIDES? Jour. Econ. Ent. 27: 291. 1934. Experimental data secured at the Ohio «.nd Wisconsin Agricultural Experiment Stations show that fluorine is an extremely toxic and dangerous poison when fed to animals. The teeth and bones are so affected that when complete data are published a psychological reaction is certain to arise against the use of any fruits or vegetables sprayed with fluorine compounds . - .38 - 7/OMACK, R. P. (110) SPRAY RESIDUE. Blue Anchor 6 (5): 18, 36-37. ' 1929. "While -the people of some nations eat arsenic and find its use helpful, others are afraid of the very minute quantity that may remain on matured fruit as a result of its use in insecticide sprays; and the removal of spray residue has gradually become one of the important problems of the pear and apple growers." The history of the spray residue situation in the United States is outlined. WOODBURY, C. G. (ill) REPORT OP THE DIRECTOR. Ind. A gr . Expt. Sta. Ann. Rpt. 32. 100 pp. 1919. Two "bearing apple trees were screened in and a colony of "bees placed in each. The trees were treated with arsenicals while in "bloom, one with a liquid and one with a dust. Dead "bees were gathered arid counted at intervals and the results showed a mortality of about 70 percent for the sprayed tree and 46 percent for the dusted tree. Other observations showed that bees do work sprayed trees when they are at liberty and there are un sprayed trees adjoining. Nearly all the dead bees gave a strong Gutzeit test for arsenic. W00DT70RTH, C. W. . (112) [REPORT OF DEPARTMENT OF] ENTOMOLOGY. Calif. Agr. Expt. Sta. Rpt. July 1, 1913, to June 30, 1914, pp. 109-118. 1914. A hive of bees was placed in the center of a 40-acre apple orchard just before spraying with an unusually heavy dose of arsenicals as the trees were just coming into full bloom. Honey stored at this time did not contain arsenic, although on analysis of some dead bees nearly a toxic dose was recovered. Therefore even under such severe conditions there is no appreciable danger to man from poisoned honey. II. LEGAL ASPECTS OF THE SPRAY RESIDUE PROBLEM ANONYMOUS (113) ARRETE DU 30 DECEMBRE 1916 MOD IF I ANT L 1 ART I CLE 2 DE L'ARRETE DU 15 SEPTEMBRE 1916 FIXANT LES CONDITIONS D'EMPLOI DES COMPOSES ARSENICAUX 7N AGRICULTURE. Jour. Agr. Pratique 81 [n. s.]: 32. 1917. Treatments with arsenical powders or washes are forbidden in vineyards, orchards, and other plantations where intercalary cultivation of market and kitchen gardens is carried on. Authorized periods for arsenical treatments are: 1. Vines, from the end of the harvest to the end of - S3 - "blossomings. 2. Apple, pear, and plum trees duri»£&s*khe period from the end of harvesting until 15 days after blossoming; at the time of full blossoming, treatments will be suspended. 3. Olive trees, June 1 to October 1. 4. Beets until a month after transplanting; 5. Osiers a.t any time; 6. Nursery trees and shrubs at any time, provided that they carry no fruit destined for consumption. (114) PROROGATION DE L'EMPLOI DES SELS ARSENICAUX DANS LA VIGMB. (DECISION MINISTERIELLE DU 27 AVRII 1921.) Rev. Agr. Afr. Nord. 19 (98): 461-462. 1921. (U5) SFRAY RESIDUE MUST 3E REMOVED, SAYS COURT. Calif. Eruit News 74 (2003) ! 3. 1926. A verdict in favor of the Government was returned by a jury in Chicago in a test suit involving 2,294 boxes of apples of the Sun Crest Orchard Company, Rogue River Valley, Oregon. The company has the choice of destroying the shipment or cleansing it of the spray used. (116) OVERCOMING SPRAY RESIDUE TROUBLES. Calif. Cult. 69 (7): 151 1927. The State department of agriculture is making every effort to assist California growers to clean their fruit and see that no shipments leave the State in violation of regulations. (117) SPRAY RESIDUE ON ERUIT. Rural New Yorker 88 (5066): 963. 1929. All fruit placed on the market in New Jersey should meet the domestic tolerance of 0.017 grain arsenic trioxide per pound. (118) SFRAY RESIDUE REGULATIONS. Calif. Eruit News 79 (2133): 9. 1929. The regulations issued by the California State Depart- ment of Agriculture for carrying out the provisions of the spray residue act of 1929 are given. SPRAY RESIDUE. Calif. Dept. Agr. Mo. Bull. 18: 363-364. 1929. Two field laboratories will be established this - 34 - season for analyzing export shipments. The domestic tolerance for the 1929 season is 0.017 grain per pound. (120) SPRAY RESIDUE AND LAW ENFORCEMENT. Calif. Dept. A g r. Mo. Bull. 18: 464. 1929. Each year the spray residue inspectors find less difficulty in enforcing the spray residue law. It is apparent that the cleaning of fruit has "become a regular practice. (121) LEAD RESIDUE LIMIT ON FRUIT IS REDUCED. Oil, Faint and Drug Rptr.- 123 (17) : 15, 29. 1933. A limit of 0.014 grain of lead per pound of fruit has been sot for the 1933 season. The arsenic tolerance of 0.01 grain of arsenic trioxide per pound is continued. Growers are warned against fluorine compounds. (122) APPLES OF DISCORD. Business Week, No. 194: 14. May 24, 1933. All apples and other foods must meet the limitation of 0.014 grain of lead per pound to avoid seizure, effective with the products shipped from the 1933 growing season. ASSOCIATION OF FOOD OFFICIALS (123) REPORT OF COMMITTEE ON SPRAY RESIDUES, ASSOCIATION FOOD AND DRUG OFF'ICIAI.3 Neo. State Hort. Soc. Ann. Rpt. 62: 41-44. 1931. Net. State Agr. Bd. *nn. Rpt. 1931: 479-483. The reduction of the arsenic tolerance to the world tolerance of 0.01 grain [arsenic trioixde] per pound for the 1931 crop of fruit is recommended. CALIFORNIA DEPARTMENT OF AGRICULTURE (124) RULES AND REGu.' .1 'IONS FOR CARRYING OUT THE PROVISIONS OF THE SPRAY RESIDUE ACT FOR 1929. Blue Anchor 6 (5): 19. 1929. CAMPBELL, W. G. (125) REPORT OF THE FOOD, DRUG, AND INSECTICIDE ADMINISTRATION. 16 pp. 1928. Supervision of interstate traffic in fruits and vegetables subject to contamination with spray residue -35- has continued. (126) REPORT OF TEE FOOD, DRUG, AND INSECTICIDE ADMINISTRATION. 18 pp. 1929. Comparatively few lots of fruit from the Pacific Northwest in 1928 contained spray residue that might b<= harmful to the consumer. The washing equipment has proved most effective. (127) REPORT OP THE CHIEF OP THE POOD AKD DRUG ADMINISTRATION. 25 pp. 1930. A systematic campaign to determine the character of sprayed fruits and vegetables entering interstate commerce and their status under the provisions of the law was in- augurated in 1919. Succeeding seasons have seen increased activity until at present the project has attained such importance that during the shipping season much time of the field force is devoted to this work. (128) REPORT OP THE CHIEF OP THE POOD AND DRUG ADMINISTRATION. 30 pp. 1931. It was seldom necessary during the past year to resort to legal action against shippers of fruits and vegetables containing spray residues, although 10 seizures of fruits and 9 of celery were made. (129) REPORT OP THE CHIEP OP THE POOD AND DRUG ADMINISTRATION. 18 pp. 1932. Steps were taken to remove 40 consignments of cabDage and 26 of celery, heavily contaminated with arsenic, from the market by seizure. Por a number of years fruit growers have been washing their fruit so effectively that the chances of its carrying excessive spray residues are small. Vegetable growers, however, have not fully realized the need for employing similar methods where heavy poisonous sprays are required as a preventive of insect and disease attacks. (130) REPORT OF THE CHIEP OP THE FOOD AND DRUG ADMINISTRATION, 1933. 19 pp. 1933. Following the adoption by certain apple pa.ckers of we.shing solvents other than hydrochloric acid, the development by the Department of Agriculture of accurate methods of - 36 - analysis for minute quantities of lead led to the discovery of commercial shipments of apples satisfactory as to arsenic hut con- taining high lead residues. On June 20, 1933, the Department announced a tolerance of. 0.02 grain of lead per pound of fruit. No tolerance is recognized 'for lead on vegetahles. A tentative tolerance of 0.01 grain of fluorine per pound was also announced. Rapid and accurate methods for fluorine determinations were devised hy the Administration chemists. During the period July 1, 1932, to March 1, 1933, approximately 7 percent of the fruit and 6 percent of the vegetahles examined for arsenic were above the tolerance. (131) REPORT OF THE CHIEF OF THE FOOD AND DRUG- ADMINISTRATION, 1934. 18 pp. 1934. The lead tolerance has "been reduced to 0.019 grain for the season of 1934. It cannot he anticipated that spray residue activities will slacken in the near future. Conditions, so far as interstate traffic is concerned, are improving. DRINKARD, A. W. , Jr. (132) THE AGRICULTURAL EXPERIMENT STATION. Report of the Director. Va. Polytech. Inst. Bull., Rpt. of the President 1930-1931: 53-59. 1932, The activities of the staff with regard to the removal of spray residue from fruit are briefly outlined. FORMENTI, C. (133) UEBER DIE VERBREITUNG GIFTIGER METALLE IN NAHRUNGSMITTELN. Z. Nahr. Genussm. 21: 265-271. 1911. Arsenic may occur in wine when the grapevines have been treated with arsenical insecticides such as lead arsenate, alkali arsenites and arsenates, copper arsenate, etc. For this reason, the French Government on Oct. 23, 1908, forbade the use of such arsenates on grapevines. GEAGLEY, W. C. (134) WHAT AN ANALYSIS OF THE SPRAY RESIDUE PROBLEM REVEALS. Mich. State Hort. Soc. Ann. Rpt. 61: 61-65. 1932. A discussion of the activities of the Michigan State Department of Agriculture with regard to' the spray residue problem and of the situation in Michigan. GRINER, J. I. (135) EXCESS SPRAY IS TABOO THIS YEAR. Better Fruit 20 (ll) : 8, 18. 1926. Great Britain will accept no exported apples having more than 0.01 grain residue per pound. Spraying practices which will minimize the amount are outlined. - 37 - H., G. H. (136) SFHAY RESIDUE, Calif. Dept. Agr. Mo. Bull. 17: 435. 1928; A letter from F. W. Pettey, senior entomologist of the Union of South Africa, is quoted. He states that in that country all apples and pears for export which have received one or more arsenical sprays must "be treated for removal of the residue "by dipping the fruit for 1 or more minutes in l/2 to 1 percent actual hydrochloric acid, followed "by draining and thorough rinsing in clean water. No fruit containing more than l/lOO grain of arsenious oxide per pound was allowed to be exported. HANSEN, A. W. (137) A DISCUSSION OF THE ARSENICAL SPRAY RESIDUE PROBLEM. Idaho State Hort. Assoc. Proc. 32: 71-76. 1927. Prom a legal standpoint there is no room for argument against the proposition that excess arsenical rprry residue must he removed. The economic demand for the removal of arsenical residue "before the fruit goes to the consumer i^ even more potent. The solution of this problem during the coming season liss in reducing spray applications to the minimum consistent with protection of the fruit, and, if necessary , adopting one of the methods of cleansing which will be recommended as a result of experimental work under way. HENQfc, P., RECKENDORFER, P., and BSRAN, P. (138) UNTSRSUCHUNGEN UBER DEN ARSENGEHALT VON TEAUBEN UND MOST ALS POLGE DER SCRADLINGSBENAMPFUNG. Wein u. Rebe 11 (l). Reprint. 5 pp. 1929. [Abstract in Rev. Appl . Ent. (A) 17: 575. 1929.] Investigations are reported on the amounts of arsenic traceable on grapes and in must as a result of the use of insecticides. The Austrian regulation forbidding (l) treatment with arsenicals after August 10 in each year and (2) the removal of grapes for wine making until 5 weeks have elapsed since the last treatment is shown to be justified. HOWARD, L. 0. (139) THE USE OF ARSENICALS IN FRENCH VINEYARDS. Jour. Econ. Ent. 21: 510. 1928. The French Ministry of Agriculture issued an order on February 25, 1926, permitting the employment of arsenicals in vineyards between the date of the yintage and the time when the grapes begin to darken the next sefa^son. - 38 - JAMES, D. M. - ' (140) HOW THE STATE DEPARTMENT OF AGRICULTURE CHECKS UPi ON ARSENICAL RESIDUES. Tenn. State Hort. Assoc. News 73: 109-111. 1932. An explanation of the activities of the Pennsylvania State Department of Agriculture with regard to spray residues on apples. LEUZINGER, H. (141) ' DIE ARSENFRAGE IN DER SCHWEIZ. Verh. Deut. Ges. Angew. Ent., 6. Mitgliederversamml. Wien 28. Sept. — 2. Okt. 1926, pp. 44-48. 1927. [Abstract in Rev. Appl. Ent. (A) 16: 6. 1928.] In Switzerland the free use of arsenical insecticides is hampered by legislative restrictions, the legislation being largely enacted by the various individual cantonal republics forming the confederation. The text is given of the regulations dated March 31, 1926, e overning the use of insecticides in the canton of Valais, and also ^he results of experiments by the author there, which show the great value of lead arsenate against the vine moths, Clysia ambiguella Hb. and Polychrosig bo t rana Schiff . MAAG, R. (142) SOMMERSPRITZUNG DER OBSTBAUME ZUR BEKAMPFUNG VON SCHORF UND OBSTMADE. Schweiz. Ztschr. Obst- u. Weinbau 34 (8): 152-156. 1925. [Abstract in R e v. Appl. Ent. (A) 13: 302-303. 1925.] At present lead arsenate for spraying can be used in Switzerland only experimentally and under special supervision. To make it better known there these reports of results obtained in 1922 and 1924 are published. A mixture of 2 percent lead arsenate solution and 1 percent bordeaux mixture T .vas used in summer, and a great reduction of attack by scab and Cydia ro iaonella was attained at a cost that was only a fraction of the crop value saved. MEEK, J. H. (143) INSPECTION PROBLEMS. V a . Eruit 21 (l): 30-36. 1933. Since the inspectors of the [Virginia] Division of Markets are in the field and in contact with the apple industry, they have been designated by the Director of the Dairy and Food Division to represent him in dealing with the spray residue problem. MELINE, J. (144) INSTRUCTION ET ARRETS DU 15 SEPTEMBRE 1916 RELATIFS A LA VENTE ET A L'EMPLOI EN AGRICULTURE DES COMPOSES ARSENICAUX. Jour. Soc. Natl. Hortic. France 17: 146-149, 1916. .' - 39 - Treatments with arsenical compounds are forbidden in vine- yards, O-rckfirds, and other plantations where vegetables and bush __f«ri1fs are grown. Treatment of vines with arsenicals must be made after flowering. Among fruit trees, only apples, pears, and plums may be treated with arsenicals. Treatments must be sus- pended during blossoming, after which they may be made again for 15 days. Arsenical treatment of beets must cease one month after transplanting. POTTS, E. C. (145) SPRAY TOLERANCE REGULATIONS FIXED. Better Eruit 21: 7. 1927. All apples and pears for export in 1927 must meet the British tolerance limit of 0.01 grain of arsenic trioxide per pound of fruit. In 1928, all fruit, whether for export or domestic trade, must meet this tolerance. For the 1927 season, fruit containing up to 0.025 grain will be passed for domestic markets, ^ashing or dipping will assure certification without further question. STEWARD, R. E. , and McKAY, CO. (146) IN THE UNITED STATES COURT OF CUSTOMS AND PATENT APPEALS. Patent Appeal Docket No. 3272. Ernest If. Brogden and Miles L. Trowbridge, appellants, v. Arthur M. Henry, apellee. Brief for appellants Brogden and Trowbridge. 88 pp. [1933?] THOMAS, S., MOTHERSHEAD, J. F. , and MENIKHEIM, I. G. (147) IN THE UNITED STATES COURT OF CUSTOMS AND PATENT APPEALS. Patent Appeal Docket No. 3272. Interference No. 58275. Ernest M. Brogden and Miles L. Trowbridge v. Arthur M. Henry. Brief for party Henry, apellee. 28 pp. 1933. UNITED STATES COURT OF CUSTOMS AND PATENT APPEAL'S. (148) TRANSCRIPT OF RECORD. UNITED STATES COURT OF CUSTOMS AND PATENT APPEALS. Patent Appeal Docket No. 3272. Ernest M. Brogden and Miles L. Trowbridge vs. Arthur M, Henry. Appeal from Board of Appeals. (Interference No. 58,275.) 625 pp. Filed Oct. 21, 1932. Printed February 8, 1933. WHARTON, T7. R. M. (149) SPRAY RESIDUES. IT. J. State H rt. Soc. Proc. Ann. Meeting Dec. 9-11, 1925. 255 VV- (85-97.) Excessive amounts of arsenical spray residues were found by the Bureau of Chemistry on Western pears in 1919, on celery from a southern State early in 1925, and on apples in New Jersey inn the fall of 1925. The activities of the U. S. Department of Agriculture in dealing with the situation are discussed. The Bureau of Chemistry would make seizure of apples containing as high as 0.01 grain of arsenic trioxide per apple. - 40 - III. REMOVAL OF SPRAY RESIDUES FROM FRUITS AND VEGETANS A. Processes ANONYMOUS (150) WARNING ABOUT CELERY SPRAYING. Market Growers Jour. 18: 339. 1916. Celery growers are being warned again by the Department of Agriculture that in spraying celery with bordeaux mixture care must be taken to see that copper is not left upon the celery. The consumer is advised, in cases where there is any reason to suspect an accumulation of copper, to break up the bunches and scrub the stalks thoroughly. (151) NET.".' RESIDUE REMOVER. Better Fruit 21 (8): 22. 1927. Also in the Farm. Jour. 51 (4): 16. 1927. W. P. Headden has developed a method of removing spray residue from apples by treating for 10 minutes in a solution of 4 lbs. of soda ash end 4 lbs. of table salt in 100 lbs. [sic] of water at 100 F., then rinsing. (152) REMOVAL OF ARSENICAL SPRAY-RESIDUE FROM FRUIT. A PRACTICAL METHOD FOR THE FRUIT GR07ER. Farming in So. Africa 2: 473, 4S3. 1927. Place all fruit showing spray stains in split cane bushel baskets and dip each basket up and down for l-l/2 minutes in a wooden trough containing a solution of 2 percent actual hydrochloric acid. Then drain for a few seconds and immediately dip vigorously up and down for 2 or more minutes in a wooden trough of cold, clean, and preferably running water. (153) REMOVING SPRAY RESIDUE. Calif. Cult. 68: 216. 1927. Quotes from H. Hartman and R. Robinson in Better Fruit. (See reference 249.) EEMOVAL OF SPRAY RESIDUE FROM PEARS AND APPLES. NOTICE TO (154) FRUIT GROWERS. So. African Fruit Grower 15 (l) : 5. 1928. F. W. Pettey' is quoted. Five methods of treatment with hydrochloric acid for the removal of arsenic are given -which differ only in the strength of acid and time of sub- mergence of fruit. The most effective is as follows: Submerge fruit 3 minutes in 1 percent hydrochloric acid - 41 (actual hydrochloric acid). Drain fruit 1 minute. Submerge fruit 4 minutes in clear running water. If water is limited and still water must be used for rinsing, an American writer advises the ad- dition of 1 pound of bicarbonate of soda to every 100 gallons of rinse water to partially neutralize the acid. (155) DIVISION 0? CEEL4ISTRY. THE SPRAY RESIDUE SITUATION. Calif. Dept . Dept. Agr. MO. Bull. 17; 467. 1928. A readjustment of wiping machines has effected an improve- ment in spray residue removal and little difficulty is being experienced. If the tolerance: on domestic shipments were the same as on export ship- ments, there would he considerable difficulty in meeting it in many cases. (156) TEE PROBLEM OF SPFAY RESIDUES ON APPLES. Amer. Agr. 122 (20): 648. 1928. Summary of an article "by H. C. McLean in the N. J. State Eort . Soc. News. (157) ACTUAL RESULTS [IN] SPEAY RESIDUE REMOVAL. Better Fruit 22 (8): 19, 27. 1928. Reports from a number of fruit packing companies are quoted. Hydrochloric acid was employed in washing the apples, usually 1 gallon to 100 gallons of water, and gave satisfactory results. (158) REMOVAL OF SPRAY RESIDUES. Farming in So. Africa 3: 835, 83?. 1928. A summary is given of results obtained in experiments con- ducted in 1928 hy Dr. F. W. Pettcy and Col. Rose for the removal of spray residue from nears and apoles "by treatment with hydrochloric acid solutions. Uith few exceptions, submergence of pears for 2 minutes in 1 percent actual hydrochloric acid, draining l/2 to 1 minute, and rinsing in plenty of practically clean water for 2 minutes at ordinary tap water temperature will effectively remove arsenical spray residues without injury. Apples may he submerged for 4 to 5 minutes in 1 percent acid if necessary to remove the spray residue, but this long period is generally unnecessary unless the fruit has "been heavily sprayed or has "been stored for some time or unless the solution is considerably "below 70° F. Then increasing the temperature of the acid solution to 80° F. will facilitate the removal. - 42 - (159) INJURY TO PEARS BY HYDROCHLORIC ' ACID SOLUTION. Farming in So. Africa 3: 375, 901. 1928. ' F. W. Pettey states that two types of injury may result from treatment of pears for the removal of spray residue "by submerging them in a weak solution of hydrochloric acid. One type consists of the collapse and "blackening of the lenticels of the skin of the fruit and the other consists of the "burning of the skin area which turns brown. (160) THE SPRAY RESIDUE PROBLEM* Calif. Cult. 73 (15): 360-361. 1929. Hydrochloric acid is recommended for the removal of spray residue. The necesity of cleaning pears and apples to be dried is emphasized as the dried fruit will contain a much larger proportion of arsenic than the green fruit. (161) WASHING FRUIT TO REMOVE SPRAY RESIDUE. Rural New Yorker 88 (5068): 1034. 1929. A public service patent (365) for acid bath fruit washing has been issued to H. Hartman and R. H. Robinson of the Oregon Experiment Station. (162) SPRAY RESIDUE ON GRAPES. Rural Sew Yorker 89: 1079. 1930. Dipping bunches of grapes in a solution of 1 gallon of concen- trated acetic acid in 100 gallons of water is recommended for the removal of spray residues. (163) ABOUT SPRAY RESIDUES. Fruits and Gardens 26 (5): 6. 1930. E. V. Shear has found the- 1 very dilute hydrochloric acid immediately followed by rinsing with water gives the best results in removing spray residue from fruit. (164) SPRAY RESIDUES. Hoosier H rt. 13: 183-186. 1931. The information presented on fruit washing is taken from the U. S. Dept. Agr. Farmer's Bull. 1687 (217), to which the reader is referred for further details. - 43 - (165) HO'"' TO EEJiiOV! SPRAY RESIDUE. Amer. Agr. 127; 216. 1931. Arsenical spray residue is removed from apples "by washing them with a solution of l-l/2 to 3 gallons of hydrochloric acid (20° Be.) in 100 gallons of water. (156) SPEAY RESIDUE REMOVAL. IT. J. Agr. 15 (5): 4, 5. 1933. The use of a wetting and degumming agent in conjunction with hydrochloric -acid, as developed "by H. C. McLean, is successful in removing spray residue from fruit treated with oil-lead arsenate sprays. (167) SPRAY RESIDUE OK VEGETABLES. Market Growers Jour. 52: 139. 1933. The method commonly used in New Jersey for removal of arsenic residue on vegetables is submergence in 1 percent hydrochloric acid. Vinegar solution has been used by a Pennsylvania gardener. (168) REMOVING ARSENICAL RESIDUE FRCu APPLES.- Agr. Gaz. N. S. Wales 45: 147-148. 1934. Dipping apples in 1 l/2 percent hydrochloric acid solution removed 90 percent of the arsenic from apples sprayed with lead arsenate alone (0.0767 grain arsenic trioxide per pound was the mean of the undipped fruit). Sodium carbonate solutions were only 2 percent less effective than the hydrochloric acid in removing the lead arsenate alone. Hydrochloric acid (1 l/2 percent) removed only 78 percent of the arsenic from apples sprayed with white oil combined with lead arsenate, and sodium carbonate solutions were even less effective. ABILDGAARD, W. (169) THE WHY AND HOW OP FRUIT '"ASHING. Neb. State Hor.t . Sec. Ann. Rpt. 61: 102-106. 1930. Under ordinary conditions, a solution of 5 to 7 qts. of commercial hydrochloric acid to 100 gals, of water is sufficient for removal of lead arsenate spray residue from apples. Late in the season it is sometimes necessary to increase the concentration to 10 or 12 qts. per 100 gals, of water. Hydrated lime is sometimes used in the rinse water, especially when water for rinsing is not available in abundance. One to 2 lbs. of hydrated lime per 100 gals, of rinse water is generally used. - 44 - -- • •'...-. (170) THIS FRJIT WASHING QUESTION. Amor. Fruit Growers 50 (12) : 4, 13. 1930. Part II. Ibid. 51 (l): 7, 23-24. 1931. The history of the arsenical sprqy residue situation and the development of fruit washing with dilute hydrochloric acid are discussed. (171) THE REMOVAL OF DIRT AND SPRAY RESIDUE FROM FRUIT. Fa. State Hort. Assoc. News 8 (1) : 33-37. 1931. Washing of apples greatly improves the appearance "by removing dirt end insect residues as well as spray residue. ALLEN, L. R. (172) A GROWER'S EXPERIENCES AND VIEWPOINT. 111. State Hort. Soc. Trans. 64: 175-177. 1930. A "brief description of the method of washing fruit for the removal of spray residue, as described in U. S. Dept. Agr. Circ. 59 (214). 3AICER, K. H. , and HEALD, F. D. (173) SOL JB. PROBLEMS CONCERNING BLUE MOLD IN RELATION TO CLEANING AND PACKING OF APPLES. Phytopathology 22: 879-898. 1932. The toxic action of 3 percent hydrochloric acid, and of sodium carbonate-borax cleaner at a concentration of 1 l/2 lbs. per gal and of sodium carbonate-tri sodium phosphate cleaner at a concentration of 60 lbs. per 100 gals, on spores of Penicillium expansum (blue mold) is of a slow type,' and no action would occur on spores on apples during their brief exposure in washing. The cleaners as used at present [1932], however , will keep the tanics reduced to a concentration of viable spores whose maximum will be that accumulated in a day's run. BALLANTYNE, J. A., and CAYZER, L. S. (174) REMOVAL OF ARSENICAL RESIDUE FROM AFPLSS. Agr. Gaz.'N. S. Wales 43: 459-466. 1932. Where oil sprays have been included in the spray program as a substitute for the late covers of lead arsenate, less arsenic is present on the harvested apples. In all cases where oil sprays have been used, less arsenic can be removed from the fruit. The arsenical residue on apples which have received as many as 6 sprayings of lead arsenate can be reduced to an amount within the world tolerance by dipping in 2 percent hydrochloric acid. At a temperature of 70° F., - 46 - 1 percent hydrochloric acid is not suitable for the removal of the residue* Two percent acid is satisfactory, hut any further increase in strength does not result in a proportional advantage. Certain varieties of apples (Statesman, Senator, Kentucky Red Streak, Delicious) which have had identical treatment in the field, when harvested differ considerably in the amounts of arsenical residue present. The wax formed on the apples during storage hinders the solvent action of the acid. Apples should be harvested at the correct stage and dipped immediately. BALLARD, F. L. (175) SPEAY-RE SI DUE REMOVAL. Country Gent. 93 (8): 42. 1928 In Oregon, arsonic\l residue has been removed from apples and pears by washing with weak solutions of hydrochloric acid. Formalde- hyde used in the acid bath keeps it free from many decay spores. BABEOS, J. A. (176) OUii EXPERIENCES IN APPLE WASHING. 111. State Kort . Soc. Trans. 54: 169-175. 1930. The results of experience in triping and washing with hydro- chloric acid (2 gals. 18 percent commercial acid to 100 gals, water) are reported. Apple washing was found to be neither expensive nor difficult. (177) THIS FRUIT WENT TO THE LAUNDRY. Amer. Fruit Grower 50 (6): 6, 17. Illus. 1930. The experience of a packing company in 1929 in washing apples with hydrochloric acid (2 gals, commercial acid to 100 gals, water) in a commercial fruit washer is described. BEAUMONT, J. E. (178) SATISFACTORY WASHING METHODS FOR SPFAY RESIDUE REMOVAL IN THE EAST. L'd. Agr. Soc. Rpt . 19: 180-186. 1935. Because of fewer codling moth sprays, the use of fungicides in most of the summer sprays, the occasional use only of stickers and summer oils, and a greater summer rainfall, there is a more- moderate spray coating on fruit grown under eastern conditions and one more easily removed to the tolerance by the simpler washing methods. Injury to washed fruit is most likely to follow ineffective rinsing. A supply of at least 1 to 2 gals, of fresh water per bu. should be provided for rinsing off all acid and soluble arsenic. If sufficient water is not available, acid in the rinse tank must be - 46 - neutralized "by adding pulverized limestone. The speed and efficiency of the reaction "between the hydrochloric acid wash solution and the arsenic and- lead residues on the fruit depend on a number of factors; . notably, the amount and character of the residue, the concentration of the acid, the temperature of the solution, the time of exposure, and the presence of a wetting agent. Lead residues not combined with mineral oil and not exceeding 0.066 grain per lb. may with reasonable certainty be removed with cold 0.5 percent acid in a flotation machine with 1 minute exposure, and similar residues not exceeding 0.10 grain per lb. may be removed with 1.5 percent acid under similar conditions. ■ Lead residues exceeding 0.10 grain per lb. or when combined with oil may be expected to re- quire more complex treatment. The effectiveness of the acid bath may be increased by heating and by the addition of a wetting agent, such as Vat sol. Fnen washing has been delayed for a week or more after harvest and the fruit has developed a heavy wax or bloom, heat- ed solutions, wetting agents and perhaps even sodium silicate may be necessary to remove the residue. The size of the fruit may also have considerable bearing on bringing the residue to the tolerance, be- cause small apples, having a greater surface per unit weight, will generally carry a heavier coating of residue. Any type of washing machine most suited to the growers' requirements can bo used, but consideration must be given to the gentleness of handling the fruit, to the flushing and rotation of the fruit in the acid tank and to the rinsing of the fruit. BEAUMONT, J. H. , and HALL1R, ivl. H. (179) RELATIVE VALUE OE SEVERAL VETTING AGENTS IH REMOVING LEAD RESIDUES FROM APPLES. Aner. Sec. Ilort. Sci. Proc. 32; 183-189. 1935. c Seven wetting agents '"ere tested at a concentration of 1 per- ent in 1-1/2 percent hydrochloric a.cid at 70 C E, ara "J.C0°F. and in the sane solution plus 1 percent salt at the sa r ie t emporatures. The authors present the following conclusions: 1. Of the wetting agents tested for their value in facilitating the removal of load residues, Igepon T and Hydrin A had no beneficial effect. Ammonium Sulfosoap was intermediate, and Vatsol, Are skat, Nekal B and DuPont No. 2 were quite effective. DuPont No. 2 and Areskat caused injury at a temperature of 100° F. to a sample of York Imperial apples that were sprayed with seven cover sprays of lead arsenate, the last four covers containing 1 gal. of mineral oil per 100 gals. 2. An increase in the temperature of the wetting agent solution from 70 to 100° F. was tremendously effective in in- creasing the efficiency of the wash. - 47 - 3. The fish and mineral oils used with lead arsenate affected the residues at harvest and also the removal of the residues "by the wetting agent solutions. The solutions on the average removed "both types of residues equally successfully. 4. One percent of salt had no effect whatever in the wetting agent solutions. 5. The interaction of wetting agent and temperature was not significant and indicates that these factors were purely additive in increasing the efficiency of the washing solution, BENTON, R, J., and POWELL, T. N. (180) REMOVING BORDEAUX SFRAY FROM ORANGES. Agr. Gaz. N. S. Wales 44: 583-684. 1933. Hydrochloric acid, from l/8 to 2 percent, was found satis- factory for the removal of residual bordeaux spray on oranges. The fruit is dipped in the acid and then in fresh water. Lipping in 1 percent sodium sulphate or sodium chloride, in addition to the acid alone, was of no advantage. Acetic, lactic, citric, and tartaric acids also readily removed the discoloration due to the bordeaux mixture, but hydrochloric acid was the most satis- factory and economical solvent. BOURNE, A. I., and ROBERTS, 0. C. (181) THE PROBLEM OP SPRAY RESIDUE. Mass. Pruit Growers' Assoc. Rpt. of 34th Ann, Conv. , pp. 101-109. 1928. Mechanical wipers were in many cases ineffective in remov- , ing spray residue to the required tolerance. Dilute hydrochloric acid (about 1 percent) and a few other substances give promise as solvents. Calcium caseinate in sprays has a tendency to increase the amount of arsenical residue present. Apples should not be sprayed with lead arsenate within 6 weeks of the time of harvest and calcium caseinate should be omitted from the latest sprays. . Dusting can be carried out later than spraying, BREGGER, J. T. (182) SPRAY RESIDUE SITUATION. Better Pruit 25 (l): 9. 1930. Dry wiping of fruit is not sufficient for residue removal when three or more cover sprays have been applied. Hydrochloric acid is the solvent most generally used in fruit washing, A two- thirds of one percent solution is ordinarily effective, but with heavier residues caused by an oil and lead combination this amount is usually insufficient. The efficiency of hydrochloric acid has been increased by the use of iron salts, sodium sulphate, and common table salt. The last seems most effective. Hydrochloric - 48 - acid may "be used up to 1-1 /3 percent (4 gals, to 100 gals, water). Waxy fruit may be treated first with kerosene emulsion (kaolin emulsifier) to remove the wax. Early cleaning is easiest. Alkaline washes are occasionally used instead of acid. (163) THE APPLE SPRAY RESIDUE SITUATION. Amer. Eruit Grower 53 (5): 5-6. 1933. The latest Eederal residue tolerances are: arsenic 0.01 grain per pound of fruit, fluorine 0.01 grain per pound, lead 0.02 grain per pound. Present washing solutions do not remove lead in the same proportion as arsenic. Either lead substitutes must be used in spraying or revised washing methods must be found which will satisfactorily remove the spray residue. BRINTON, C. S. (134) THE SPRAY RESIDUE PROBLEM IN DELAWARE. Del. Bd. A g r. Quar. Bull. 20 (5); 74-81. 1931. In the future undoubtedly heavier applications of lead arsenate will have to be made and all apples will have to be washed. The world tolerance will "be in force for domestic shipments within a year or two. Dipping in weak muriatic acid followed by rinsing is recommended as a cleaning method, BROCK, W. S. (185) APPLE WASHING PROBLEM.' la. State Eort. Soc. Rpt. 1930: 137-140. The history of the spray residue situation is sketched. Washing with hydrochloric acid (3/4 to 2 percent) is recommended for the removal of arsenical residue. BROWN, C. L. (186) STRICTER RULES EOR SPRAYS. Country Gent. 103 (9): 54. 1933. Fcr the removal of arsenic residue alone, alkali solutions appear most effective; for lead arsenate weak hydrochloric acid is believed more efficient. BURKHOLDER, C. L. (187) THE PROBLEM OF SPRAY RESIDUE REMOVAL FROM THE FRUIT GROY/ERS' VIEW- POINT. Mich. State Hort. Soc. Ann. Rpt. 61: 70-74. 1932. Switching from lead arsenate to oil sprays after July 1, on Ben Davis apples, in 1931, did not reduce the arsenical load at picking time. Increasing the strength of acid above 1 percent by - 49 - volume in the dipping tank method failed to give enough "better results to warrant the practice. Using 2 percent acid in a "brush type Bean washer, two-thirds of tho original arsenical load was removed on the average. The dipping tank method averaged only 50 percent removal. — and ford, o v/. iies) 7,'ASHING APPLES TO REmOVE RESIDUE IK 1931. Hoosier Hort. 14: 107-111. 1932. The "brush type washer can he defended on to remove about two-thirds of the arsenical load present. Increasing the strength of hydrc -.hlorie acid wash solution from 2 to 3 per- cent by volume did not Increase the percentage of arsenic removed with a cold solution, A cold wash of 1 02 of sodium metasilicate per gal # was slightly less efficient than 2 or 3 percent cole! hydrochloric acid. Cold sodium metasilicate plus a seal emulsifier gave a higher percentage of removal than hot (90° 1. ) sodium metasilicate without emulsifier. Hot (90° F ) 2 percent hydrochloric acid skewed a slight increase in efficiency as compared to cole 2 percent acid. The advantage was too slight to warrant the extra expense and labor of adding heating equipment to the washer. and »0ED, 0. W. (189} 1931 AND 1932 RESIDUE AND UASHER RESULTS FROM PURDUE FARM, BEDFORD. Hoosier Hort, 15: 68-70, 1933, Cold 2 percent hydrochloric acid gave as good removal of arsenical spray residue as any of the materials tried (others were hydrochloric acid at 90°, hot (90°) and cold sodium metasilicate, 4 percent hydrochloric acid, and hydrochloric acid plus soap emulsifiers). Very little difference in arsenical load at harvest or in cleaning efficiency of 2 percent hydrochloric acid resulted when 1 or 2 percent oil sprays were used in place of regular sprays for second-brood applications. and FORD, 0. T7, (190) CASHING- APPLES TO REMOVE RESIDUE IN 1931. Ind. Hort. Soc. Trans. 1931; 64-72. 1932. Ind. Hort. Sec. Trans. 72! 124-127, 1932. Hoosier Hort, 14 (7): 107-111. 1932. Increasing the strength of hydrochloric acid from 2 percent to 3 percent by volume did not increase the percentage of arsenic removed with a cold solution. A cold wash of 1 oz. of sodium metasilicate per gal # of water was slightly less efficient than either 2 or 3 percent cold hydrochloric acid. There was some indication that a soap emulsifier added to the cold sodium metasilicate solution slightly increased the removal. Cold - 50 - sodium metasilicate plus emulsifier gave a higher percentage of removal than hot (90°F.) sodium metasilicate without emulsifier. Hot (90°) 2 percent hydrochloric acid showed a slight increase in efficiency as compared to cold, but the advantage was so slight that it did not warrant the extra expense and labor of adding heat- ing equipment to the washer. — and FORD, 0. W. (191) THE 1934 SPRAY RESIDUE SITUATION IN INDIANA. Hoosier Hort. 16 (7); 99-101. 1934. Under the schedule and weather conditions of 1933, the arsenic load was cleaned to well below the tolerance with 3 percent "by volume hydrochloric acid. All other treatments were also well "below 0.01 grain arsenic trloxide per pound except samples run through a dry cleaner. All samples run through the acid averaged just 0.02 grain of lead after washing. Waxy varieties were not cleaned to 0.02. Samples run through acid alone at 100° barely met the 1934 tolerance of 0.C19. In other words, a 30-second exposure at higher tempera- tures did not increase removal to any worthwhile extent. Three per- cent acid by volume plus 5 lbs. of Vat sol to 100 gals, at 55° F. re- sulted in removal to just below the 1934 tolerance. This wash at 100° F. showed only slight increase in removal over 65° F. Of the defoaming agmts used, coconut oil burned the fruit and sulphonated coconut oil left the fruit sticky even after 5 months storage. De- foamer No. 16, a naptha-wool grease combination, reduced foaming satisfactorily and did not injure the fruit. — and FORD, 0. W, (192) NOTES ON 1934 APPLE WASHING WHICH ARE OF SPECIAL INTEREST TO INDIANA GROWERS. Ind. Hort. Soc. Trans. 1934: 85-91. 1935. Four types of apple washing equipment were studied during 1934; (1) a new mc lei X flotation washer, (2) a new model E under- brush-flood washer, (3) tandem washing with hot sodium silicate and a wetting agent in a specially constructed underbrush washer, follow- ed by acid in the model X flotation washer, and (4) a dual washing treatment in which not sodium silicate and a wetting agent were used in a home-made flotation unit followed by a 20-second exposure to acid in a flood type washer. Equipment no. (2) was very efficient in residue removal; with 1 l/2 percent acid plussl percent Vastol, the percentage removal on lead-oil sprayed Winesaps carrying 0.3297 grain of lead per lb. was 85 percent for 20 seconds exposure at 110° P., and 93 percent for 30 seconds; with 2 percent acid it was 88 percent for 20 seconds and 91 percent for 30 seconds. When treatment no. (4) was used, preceded by a dry cleaning and allowing 1 1/2 minutes' exposure to sodium silicate and 1 percent Vat sol at 90 to 108° followed by 30 seconds' exposure to cold 1 l/2 percent acid in the flood- type washer, a lead removal of 90 to 97 percent was consistently obtained. All samples analyzed for this method - 51 - were run within 24 hours after picking. Method (?) could be depended on to give 80 to 35 percent lead removal on Wine saps carrying a lead load of 0.3297 grain and held for 2-1 /2 weeks, when 75 lbs. of sodium silicate plus l/4 percent vat sol for 30 to 40 seconds was followed by' cold 1 l/2 percent acid for 2 minutes. BURTNER, J. C. (193) THE SPRAY RESIDUE PROBLEM. Amer. Fruit Grower Mag. 47 (8): 5, 13, 17. 1927. The development of the spray residue situation from 1921, when Boston made some protest on the subject, up to the time of writing is outlined. The recommendations of R. K. Robinson and H. Eartman. on spray residue removal (363) are summarized, CARTER, R. K. (194) AN INVESTIGATION OF SOLVENTS FOR THE REMOVAL OF LEAD ARSENATE RESIDUES FR0:i FRlTIT. Jour. Econ. Snt . 27: 848-853. 1934. Most of the common inorganic acids are apparently strong enough to attack lead arsenate to a greater or less degree. Those acids which furnish ions capable of forming soluble salts with both ljad and arsenic exert a true solvent effect. Hydro- chloric acid is the best in this respect. Those acids which furnish ions capable of forming insoluble lead salts (such as sulphuric and chromic) are capable of dissolving more arsenic but a smaller amount of lead. Organic acids are apparently too weak to exert a solvent action on lead arsenate but are capable of undergoing reactions with it, causing precipitation of insoluble lead salts. Solutions of salts alone or when mixed with acids to not have an appreciable solvent action unless they also cause reactions forming other insoluble compounds. A high concen- tration of sodium chloride in hydrochloric acid may be of benefit in dissolving lead chloride. Some of the alkalines, especially sodium silicate and sodium hydroxide, are capable of dissolving appreciable quanti- ties of both lead and arsenic. Weak alkalies, such as ammonium hydroxide and organic amines, do not have appreciable action. The addition of salts to solutions of alkalies may be of some benefit and offers a field for further investigation. The use of wetting agents and degumming soaps may be of some benefit in removing lead arsenate spray residues through the physical action of increased wettability but probably do not have much solvent action per se. - 52 - — (195) SOLVENTS FOR CRYOLITE: Jour. Econ. Ent. 27: 863. 1934. Sodi"um chloride decreases the solubility of cryolite in dilute hydrochloric acid. Sodium chloride, sodium bicarbonate, and monosodium phosphate each decrease the solubility of cryolit.e in water at 20° C. Several com- pounds, including boric acid, aluminum salts, and ferric salts, increase the solubility of cryolite in 1.5 percent' hydro- chloric acid (1.5 g. HC1 per 100 cc.) and in water. CHAPMAN,' P. J. (196) THE APPLE MAGGOT. N. Y. State Hort. Soc, Proc 76th Ann. Meeting, pp. 201-210. 1931. The washing machines using 1 or 2 gals, of commercial hydrochloric acid in 100 gals, of water may be expected to satisfactorily reduce the arsenic in residues now [1931] encountered in New York. Dry cleaners improved the appearance of the fruit by removing dust and sulphur residues, but are less efficient than washers in arsenic removal, hardly removing one-third of the poison. The desirable machine should in- clude the principle of an acid wash for arsenic removal in conjunction with the brushing or wiping principle for the removal of dirt, the blackened honeydew associated with aphis and pear psylla, and the spotting from leaf-hoppers. and PEARCE, G. W. (197) THE SPRAY RESIDUE PROBLEM OP CURRANTS. I. Y. State Hort. Soc. Proc. 1935: 250-265. It is more difficult to reduce lead to the tolerance than arsenic. In view of this, one might well consider using calcium arsenate in place of lead arsenate on the fruit trees in currant plantings. Stemming of currants removes a con- siderable amount of the spray residue. Immersion of currants in 1 percent hydrochloric acid for 2 to 3 minutes, followed by thorough rinsing in clean water, is recommended. Jelly made from currants bearing approximately 3 times the tolerance for arsenic and 5 times the tolerance for lead contained well below the legal limits for both materials. Two lots of fruit analyzing 0.01 grain of arsenic tri oxide per pound yielded juice analyzing 0.005 and 0.004 grain of arsenic and 0.007 and 0.008 grain of lead per pound, respectively. - 53 - CHILDS, L. (198) THE PROBLEM OF ARSEIICAL RESIDUES: THE SITUATION IK DIFFERENT APPLE-GROUING AREAS AND RESULTS OF INVESTI- GATIONS RELATIVE TO THE PRODUCTION OF APPLES TO MEET MARKET REQUIREMENTS. 4th Internat. Congr. Ent., Ithaca, Aug. 1938, pp. 675-687. 1929. The history of the arsenical spray residue problem is given. Generally speaking, fruit washed immediately after harvest can "be reduced within 30 seconds to 0.01 grain of arsenic trioxide per pound with a concentration of 1 percent commercial acid (0.33 percent actual acid) with jet and flood wash '.machines. CLARKE, J. 0. (199) ADMINISTRATION. OF. THE RESIDUE TOLERANCE.. 111. State Hort. Soc. Trans. 64: 154-169. 1930. A general discussion of the spray residue situation. Washing of apples with hydrochloric acid is recommended. On 42 samples so washed, the arsenic before washing ranged from 0.040 to 0.002 grain and afterwards from 0.019 to a trace. Only one sample was above the domestic tolerance and 3 above the world tolerance after washing. COHEE, R. H., and ST. JOHN, J. L. (200) LEAD URSOLATE IN RELATION TO FRUIT CLEANING. Indus, and Engin. Chem. 26: 781-782. 1934. Lead ursolate was prepared from ursolic acid isolated from apple wax. This salt is insoluble in 1.5 percent hydrochloric acid and slightly soluble in 10 percent sodium silicate. Interference of wax in fruit cleaning may be due, in part at least, to the formation of such a compound on fruit sprayed with lead arsenate. Evidence of the- presence of an organic lead compound on sprayed fruit is presented. The solubility of lead ursolate in 10 percent sodium silicate is increased by the addition of 1 percent of chloro- form, benzene, toluene, or xylene. The results obtained may help to explain the lack of relation noted between the solu- bility of lead arsenate in different washing solutions and their relative effectiveness in actual fruit cleaning. COPPER, E. G. (201) THE SPRAY RESIDUE SITUATION. Amer. Agr- 130: 259. 1933. As early as 1919, the U.S. Department of Agriculture made - 54 - detentions of western apples containing excessive amounts 'of spray residue. In 1925 and 1926 a great deal of western fruit was detained* Investigations started about this time showed that a dilute hydrochloric acid wash was very effective for the removal of arsenical residue. Some "baths, such as tri- sodium phosphate, effectively remove arsenic "but have no effect on lead. 3oth lead and arsenic are cumulative poisons. Efforts are being made to find a substitute for lead arsenate as a spray material. COX, A. J. (202) FACTS CONCERNING THE SPRAY RESIDUE PROBLEM PERTINENT TO THE FRUIT AND VEGETABLE INDUSTRIES. Calif. Dept. Agr. Mo. Bull. 22: 389-396. 1933. There is a growing demand for more rigid enforcement of the spray residue lav/. Washing of apples and pears with 1 percent hydrochloric acid plus 1 to 2 percent ordinary salt at 100° to 110° F. is recommended for removal of arsenic and lead. (203) CALIFORNIA SPRAY RESIDUE PROBLEMS. Pacific Rural Press 127: 166, illus. 1934. Wiping or brushing methods of cleaning fruit cannot be depended upon to remove more than a small part of the poisonous residues. Simply washing in water has very little effect on spray residue. Hydrochloric acid has proved to be the most satisfactory washing material. In general, a con- sistently maintained 1 percent solution of hydrochloric acid (3 gals, commercial acid to 100 gals, water) at 100° to 110 u F. , with 1 or 2 percent common salt (8 to 16 lbs. to 100 gals, solution) will suffice for adequate removal of spray residue in 40 seconds under California conditions. The acid wash should be followed by thorough rinsing in clean, fresh water and, if possible, a fresh water spray. Fruit may be tested for freedom from acid as it leaves the rinse water by placing the corner of a small piece of litmus paper into the calyx. If the paper turns red quickly, the rinsing is inadequate. COX, T7. T. (204) REMOVAL OF SPRAYING RESIDUE. Rural New Yorker 90: 343. 1931. A brief general discussion. Washing with hydrochloric acid, 1 gal. to 100 gals, of water, is recommended. - 55 - DE SELLEM, P. E. (205) WASHING APPLES KITE BY,' SODIUM SILICATE. Wash. State Hort. Assoc, Proc. 23th Ann. Meeting 1932: 124-127. BV sodium silicate Was onip 1 oyed, at concentrations ranging from 53 to 130 lbs. per 100 gals, of water, to clean apples. It cm he used at temperatures of 115° to 120° P. without injury to the fruit. The cleaning efficiency is in- creased when foaming occurs. The waxier the fruit, the more easily it is cleaned. The efficiency apparently increases after a number of boxes of fruit have passed through the solution. Twelve thousand loose boxes have boen washed without having to dump the solution. BW sodiom silicate does not break down as quickly as the other alkalies - (soda ash and trisodium phosphate). DIEHL, H. C. (206) SUGGESTIONS DERIVED PHOM SPRAY RESIDUE REMOVAL EXPERIENCES OP 1927 SEASON. Better Fruit 22 (12): 13-14, 18-19. 1928. Dry cleaning is less satisfactory than washing. The concentration of hydrochloric acid used in washing should be at least one gallon to the hundred. The solution should be wanned to st least 80 e to 85° F., preferably 90° to 100°. (207) LEAD ARSENATE OIL SPRAYS AND RESIDUE REMOVAL. Wash. State Hort. Assoc. Proc. 25: 69-88. 1929. The following measures are recommended to reduce lead arsenate residues on fruit: (l) Avoidance of so-called heavy oils in spraying. These are oils with high viscosity and low volatility and when used with lead arsenate made residue removal very difficult. (2; Reduction of the load of lead arsenate on fruit as much as possible without sacrificing con- trol, by using substitute insecticides or supplementary methods of control. (3) Combination lead arsenate-oil sprays should not be applied to fruit closer to harvest time than from 4 to 6 weeks. (4) Avoidance of the application of oil over blotched deposits of lead arsenate on fruit. The addition of sodium chloride and sodium sulphate to warm dilute acid solution facilitated the removal of lead arsenate residues. The addition of kerosene emulsion is also helpful with apples difficult to clean. Other materials, such as toluene and benzene emulsions, ethyl and methyl alcohol, and similar solvents are being tested. Voluminous data on fruit washing are presented in tabular form. - 58 - SPRAY RESIDUE REMOVAL FROM APPLES AND PEARS. Fruits and Gardens 28 (S)r 6-7, 10-11. 1930. (208) The use of hydrochloric acid, at least 1 gal. of commercial acid to 100 gals, of water and not more than 4 gals. to 100 gals, is recommended. Heating to at least 80° to 85° F. , and to 90° or 100° for fruit difficult to clean, greatly in- creases the efficiency of the operation, enabling the acid con- centration to be lowered. The addition of salt to the washing solution often enhances its efficiency. Kerosene emulsion prepare u with kaolin aids in cleaning fruit which has been treated with a spray containing oil and lead arsenate. Thorough rinsing is important to prevent soluble arsenic injury and decay. If fresh rinse water only cannot bo used, the addition of lime to it will neutralize the acid carried over by the fruit and render insoluble any remaining arsenic. (209) SPRAY RESIDUE REMOVAL BY LATEST METHODS IS AN ECONOMIC BENEFIT.' Yearbook of Agr. 1931: 484-487. 1931. Dry cleaning is not generally satisfactory for removing excessive a.rsenical spray residue. Fashing methods employing hydrochloric acid are oy far the rost frequently used, although alkaline materials may also be employed. The latter are generally efficient, but because of the solvent action of alkalies upon the waxy coating of the frait, their use must be supervised rather closely, particularly the rinsing phase. Simple dipping methods are relatively inefficient. The satisfactory washing of apples and pears generally requires an acid concentration of at least 1 gallon to 100 gallons of water. The commercial grade of hydrochloric or muriatic acid is used. The time required to remove spray residue depends upon the variety and maturity of the fruit, the amount of residue present, the strength and temperature of the acid solution, and the method of application. The addition of common salt to the acid solution will often en- hance its cleaning efficiency, particularly if the solvent is warmed. One percent salt by weight dissolved in the wa.shing solution has generally been sufficient. The use of 2 or 3 gallons of fresh water per bushel of fruit is desirable for rinsing. — - EZELL, B. D., and RYALL, A. L. (210) SOME FACTORS IN SPRAY RESIDUE REMOVAL. Better Fruit 23 (9): 9-11, 24, 26, 28. 1929. Diffused spray, stream wash, flood wash, flotation, and - 57 - modified "box dip types of fruit washers are satisfactory. The concentration of acid required for cleaning different varieties increases in the following order: Winter Banana, Jonathan, Delicious, Spitzenberg, and Winesap. From l-l/2 to 2 gals, of acid per 100 gals, of water for Jonathans and 2 gals, per 100 for Delicious and later varieties is advis- able. Warming the solution increases the ease of cleaning. — EZELL, B. D., and RYALL , A. L. (211) RELATION OF SOME FACTORS IN STRAYING AND CLEANING PRACTICES TO EFFICIENCY OF REMOVAL. Idaho State Hort . Assoc. Froc. 34: 25-33. 1929. Dry cleaning methods are less satisfactory for residue removal than washing is. Satisfactory methods of applying the solvent solution to the fruit are: (1) fan-shaped, diffused spray, using either acid or warm alkaline solution, (2) stream wash, (3) flood wash, (4) flotation, (5) modified "box dip, or certain combinations of these. Proper washing of apples and pears generally requires at least 1 gal. of acid per 100 gals. If the fruit is from ranches where the spray schedules have varied and some apples may "be difficult to clean, it is advisable to use l-l/2 to 2 gals, of acid per 100 gals, as a. minimum for Jonathans and at least 2 gals, for Delicious and later varieties. In some cases even higher concentrations have been required, up to 6 gals, of acid per 100 gals. , but more consistent cleaning is obtained by warming the acid at a lower concentration when these high cold con- centrations seem necessary, or even fail, to reduce the residue satisfactorily. The use of fish oil with lead arsenate and of heavy technical oil following or preceding lead arsenate makes cleaning more difficult. and FAHEY, J. E. (212) SUGGESTIONS FOR THE USE OF ADDITIONAL SOLVENTS FOR INCREASING THE EFFICIENCY OF HYDROCHLORIC ACID AS A CLEANSIKG SOLUTION FOR APPLES. 2 pp. mimeo. , Oct. 1930. The procedure to be used in washing apples when the additional solvents are used which have been described by A. L. Ryall and the authors (219) is described in greater de- tail. From 1 to 2 percent of salt by weight and a temperature of 90° to 100° F. are recommended for most cases. When clean- ing is exceptionally difficult, kerosene emulsion is helpful, but should be used only in machines providing constant agita- tion. The emulsion is made up from l-l/3 lbs. kaolin, 1 gal. kerosene, and l/2 gal. water. The use of l-l/2 gals, per 100 gals, of washing solution is recommended. - 58 - and FAHEY, J. E. (213) THE EFFECT OF FISH AND MINERAL OIL SPRAYS IN PROBLEMS OF ARSENICAL SPRAY RESIDUE REMOVAL. Wash. State Hort. Assoc. Proc. 27: 57-60. 1931. Fruit receiving six cover sprays of Dead arsenate with either mineral oil or fish oil could not be cleaned with 1 percent hydrochloric acid or 1 percent hydrochloric acid plus 1 percent salt at temperatures "below 100° F. The fruit con- taining fish oil was not cleaned' satisfactorily "by a solution containing 1 percent hydrochloric acid, 1 percent kerosene emulsion, and 1 percent salt at 100° F. This treatment did satisfactorily clean fruit sprayed with mineral oil.' An alkaline phosphate solution (60 lbs. trisodium phosphate per 100 gals.) at 115° F. removed residue from fruit sprayed with fish oil satisfactorily hut was not so efficient for fruit sprayed with mineral oil. FISHER, D. F. , HARTMAN, H. , MAGNESS, J. R. , (214) and ROBINSON, R. H. REMOVAL OF SPRAY RESIDUE FROM APPLES AND PEARS IN THE PACIFIC NORTHWEST. U. S. Dept. Agr. Circ. 59. 20 pp. 1929. General aspects of spray- residue removal, cleaning fruit by wiping or brushing, and cleaning fruit by solvent methods are discussed. The dry-cleaning methods, under the best conditions, do not consistently remove from apples more than about 30 percent of the spray residue on the fruit when the uncleaned fruit shows not more than 0.04 grain of arsenic tri oxide per pound. Various types of washers are discussed. Hydro- chloric acid was used for cleaning in most cases. The amount of acid necessary was less at higher temperatures. In many cases 1 or 2 gals, of acid to 100 gals, of water was sufficient if the solution was warm. A warm alkaline solution was also employed in cleaning fruit in a flotation type washer. and FLETCHER, L. A. (215) FRUIT CLEANING METHODS AND THEIR EFFICIENCY. Wash. State Hort. Assoc. Proc. 23: 150-162. 1927. Warming the hydrochloric acid solution used for washing apples distinctly increases its efficiency, so that lower acid concentrations may be used. For average waxy fruit in Wenatchee, having not over 0.05 grain of residue content [arsenic tri oxide], l/2 percent actual acid concen- tration has generally been sufficient, and in some cases as low as l/4 percent, but with fruit more difficult to clean, 3/4 percent has been used successfully. It is desirable to use only the minimum concentration which will do the work. The temperature of the solution should be at least - 59 - 80° F. and preferably 90° to 100° for fruit difficult to clean. — and FLETCHER, L. A. \ (216) FRUIT CLEANING METHODS. Better Fruit 22 (8): 18. 1928. Warming the acid bath increases its efficiency. The temperature should "be at least 80° F, , and for fruit difficult to clean 90° to 100°. For average waxy fruit in Wenatchee, Wash., having not over O-.05 grain arsenical residue per pound, l/2 percent actual acid concentration has been gen- erally sufficient; with fruit more difficult to clean, 3/4 per- cent has been used successfully. LUTZ, J. M.., and RYALL, A. L. (217) REMOVING- SPRAY RESIDUE FROM APPLES AND PEARS. U. S. Dept. Agr. Farmers' Bull. 1687. 31 pp. 1931. Brushing or wiping will remove only a relatively small proportion of the residue from all of the fruit, even if the equipment is properly cared for. Hydrochloric acid has been found the most satisfactory solvent for the removal of arsenical residues from apples and pears. Proper washing requires at least 1 gal. of commercial acid to 100 gals, of water. For average lots of fruit with no particular spray-material complications, 2 to 3 gals, of commer- cial acid to 100 gals, of water usually are enough. Use of more than 4 gals, to 100 is not recommended. Sodium hydroxide, when used alone in concentrations up to 15 percent by weight, is an effective solvent for arsen- ical residues where no basic fungicidal residues are involved, but it makes thorough rinsing very difficult and attacks the waxy coating of the fruit as well as the residue. It is par- ticularly likely to injure russeted pears. Sodium carbonate or similar milder alkalies may be used with a fair degree of safety in concentrations of about 5 per- cent, but their full effectiveness is generally obtained only when the washing solution is warmed to 100° F. or above. Raising the temperature of the acid solution gives in- creased cleaning efficiency. The temperature should be at least 80° to 85° F., preferably 90° to 100°. Various methods of heating the solution are discussed. Where difficulty is experienced in washing apples be- cause of heavy spray oil deposits or natural waxiness of the skin, kerosene emulsion added to the regular acid wash is helpful. The following formula is satisfactory: 2-l/3 lbs. kaolin, 1 gal. water, and 2 gals, kerosene, preferably the odorless type. - 60 - Addition of 1 to 3 percent of common salt to the hydrochloric acid Wash, in many cases has resulted in more thorough removal of the lead arsenate residue. The use of certain concentrations of salt also makes it possible to wash pears in the flotation type washer. : '" ', Proper rinsing of the fruit is very important. Use fresh' water, only for rinsing. If the same water, must, be used continuously, -some substance such as lime may be added to neutralize the hydrochloric acid carried over by .the fruit and to render insoluble the arsenic remaining on,. the. fruit after washing. Lime water can be made up by preparing a stock solution of milk of lime by slaking 1 lb. of fresh quicklime and adding water to make it up to 1 gal. Usually 1 gal. of this solution added to 50 gals, of rinse water is sufficient. If preferred, hydrated lime can be. added directly at the rate of ; 1-1/2- to 2 lbs. to 50 gals, of rinse water. Broken limestone placed directly in the rinse tank may also be used, but is less effective. Several type's of washers are pictured and described, and directions are given for building a paddle washer. .PEUTZER, W. T. and FLETCHER, L. A. (213) STUDIES ON THE REMOVAL OF SPRAY RESIDUES FROM APPLES AND PEARS. Part I. Methods of cleaning apples and pears. Bureau of Plant Indus. , U. S. Dept. Agr. (multigraph) , June 28, IS 28. 18 pp. The average efficiency of removal of arsenical residue from apples by 4 dry-cleaning methods ranged from 22 to 33 percent. In some cases, dry-cleaning methods added more residue to the fruit than it originally bore. Six methods employing a hydrochloric acid wash were studied: (1) diffused spray, (2) forceful jet spray, (3) flood wash, (4) flotation, (5) combination of overhead diffused spray and flotation, and (6) tank dipping in boxes.- The following conclusions were reached: (l) It is not safe to assume that any washing method will satis- factorily clean all fruit, regardless of its previous treatment both as to spraying practices and method of har- vesting. (2) Any washing method that applies the solvent solution to the fruit by diffused spray, flood wash, flo- tation, or a combination of these should give satisfactory results for ordinary cleaning requirements. (3) The cleaning efficiency obtained with dipping methods, as commonly practiced, was less than that obtained with washing machines that in- cluded some form of spray or flood wa.sh, when used under similar conditions. (4) Where difficulty was experienced in cleaning fruit, prolonging the exposure of the fruit to the washing treatment longer than the common practice in - 61 - 1927 did not result in any marked improvement. (5) The proper washing of most apples generally requires an acid concentration of at least 1 gallon (32 percent acid) to 100 gallons. (6) By raising the temperature of the acid solution, increased cleaning efficiency was obtained in washing apples from which the residue could not he otherwise satisfactorily removed. (7) The proper adjustment of all parts of the wash- ing equipment should not "be overlooked at any time. (8) Rins- ing of the fruit is a very important part of the process, especially if alkaline solvents are used. (9) Reasonable dry- ing of the fruit seems essential to facilitate packing and to insure proper storage life to the fruit. (10) The polishing of apples after drying is not always essential if they are cleaned properly. — RYALL, A. L., and FAHEY, J. E* (219) ADDITIONAL SOLVENTS FOR INCREASING THE EFFICIENCY OF HYDRO- CHLORIC ACID AS A CLEANING SOLUTION FOR APPLES. 'Northwest Fruit Grower 2 (35): 8, 13. 1930. Also in mimeographed form, Oct. 1930. Common salt, when added to the hydrochloric acid wash, increased the efficiency and allowed the same efficiency to be obtained with less acid. A stable kerosene emulsion loosens the waxes and oils on apples and make removal of spray residue less difficult. DOLMAN, CD. (220) DETERGENTS AND USE IN RESIDUE REMOVAL. Wash. State Hort. Assoc, Proc. 28th Ann. Meeting 1932: 102-117. Hydrochloric acid does not readily clean waxy fruit or fruit sprayed with fish oil or soap. Soda ash cleans readily, but when the temperatures have to be raised above 110° F. damage results. Trisodium phosphate cleans well when the solution is fresh. This material cannot be used at temperatures above 110° F. without danger of damage to the fruit. It also has a tendency to break down after short use, so that it does not clean. Sodium silicate (50 to 101.8 lbs. 331 sodium silicate per 100 gals, water) was found effective at temperatures as high as 128° F. without damage to the fruit. The highest number of boxes of fruit cleaned without changing the solution has been 28,000 boxes. ELLETT, XI. B., and MILLER, M. P. (221) THE REMOVAL OF SPRAY RESIDUE FROM APPLES. V a . Agr. Expt. Sta. Rpt. 1919-1927, pp. 142-148. 1928. Hydrochloric acid of 2.5 percent strength will remove over 90 percent of the arsenic residue in 5 minutes at 70° F. - 62 - In strengths of 2.5 and 5 percent it removes all signs of spray residue when either lead arsenate or bordeaux mixture plus lead arsenate is used. The copper is dissolved also. One per- cent hydrochloric acid removes over 50 percent of the arsenic at ordinary. temperatures. When higher temperatures were used, the fruit turned dark. A 5-percent solution of sodium hydroxide removed 80 to 85 percent of the arsenic from fruit sprayed with lead arsenate or lead arsenate plus bordeaux. Sodium hyposulphite was found unsatisfactory for removing spray residue. Sodium chloride plus sodium carbonate, used at a strength of 4 percent of each, was effective in removing the residue when the apples were allowed to stay in the solution 10 minutes at 100° F. Hand Piping or treatment of apples with water was found unsatisfactory. FAHEY, J. E. (232) SPECIAL PROBLEMS IN THE REMOVAL OF SPRAY RESIDUES FROM APPLES. Wash. State Hort. Assoc. , Proc. 28th Ann. Meeting, pp. 119- 123. 1933. The most common cause of difficult spray residue removal is the adoption of unusual spray programs, especially those in- cluding the excessive use of mineral oil with lead arsenate or the use of combination mineral oil and lead arsenate sprays late in the growing season. Another very important residue re- moval problem is that of cleaning over-mature fruit. No matter whether the fruit is on the tree or in storage when the waxy coating is formed, the result is the same. Alkali is usually more effective than acid in removing the residue from over- mature fruit. Unusual spray materials, such as flour and lime, introduce another hazard in spray residue removal. Most fruit-washing equipment now marketed is adapted to the use of either alkali or acid for spray residue removal, but come of the home-made machines and older commercial models are built to give satisfactory results with only one of these materials. FARLEY, A. J. (223) SOME EXPERIENCES WITH SPRAYING AND SPRAY RESIDUE REMOVAL IN NEW JERSEY. N. Y. State Hort. Soc. , Proc. 78th Ann. Meeting, pp. 87~92. 1933. Also in Mass. Fruit Growers Assoc, Inc., Rpt. 40: 87-96. 1934. Chemical washing removes spray residues more effectively than mechanical methods. Dilute hydrochloric acid in con- centrations of 0.5 to 1.25 percent by weight is the chemical used almost exclusively in New Jersey. It has been found that 5 minutes' contact with a dilute acid solution, immediately after the fruit is harvested, will reduce the arsenical residues well below the tolerance of 0.01 grain of arsenic trioxide per pounds. Vatsol, a de gumming soap, is sometimes added to the - 63 - dilute hydrochloric acid solution when the apples have an exceptionally heavy arsenical residue or if the use of oil in combination with lead arsenate nakes it difficult or impossible to remove the residue with less than a 2-percent acid solution. Spray residues should be removed immediately after harvesting, as the residues become inbodded in the natural wax coating of fruit if washing is delayed. (224) ESUOVI^TG SPRAY RESIDUE. Va. Fruit 22: 133-140. 1934. Most of the information in this article is based on work done by McLean and Weber at -the New Jersey Experiment Station. A mixture of 5 to 5.5 gals, of 20° Be. hydro- chloric acid and 8 lbs. of Vatsol to 100 gals, of water, to which fruit is exposed for 1-1 j 2 to 2-1 j 2 minutes, has been developed for removing excessive lead and arsenic residues where oil has been used in combination with lead arsenate sprays. Apples, so sprayed, with a residue of 0-17 grain of lead per pound, showed only 0.009 grain per pound after washing with this mixture, whereas acid alone only reduced the lead to 0.056 grain per pound. When Vatsol is used in flood or spray type commercial washers, Degras, a crude wool grease product, may be used to control excessive foaming. FISHER, D. F. (225) HETC3B DEVELOPMENTS II\ T THE WASHING OF FRUIT. Md. Agr. Soc. Rpt. 15: 210-220. 1930. Dry cleaning is inferior to washing. In most eastern fruit sections it is not necessary to use hydrochloric acid stronger than 1 or 2 percent by volume, i. e. , 1 or 2 gals, of commercial acid to 100 gals, water. The addition of 8 lbs. of salt per 100 gals, of acid solution increases the effective- ness of the wash about as much as doubling the strength of the acid. If the temperature of the acid is increased from 50° to 70° F. the solvent action is increased about 15 percent. 3y raising the temperature to 100° the efficiency can be increased about 25 percent. Kerosene emulsion added to the acid and salt solution is useful with fruit which has been sprayed with oil and that which has. become waxy. A suitable emulsion consists of l-l/3 lbs. kaolin, 1 gal. kerosene, and one-half gal. soft water. Kerosene emulsion should be used only with washers which keep the solution rather violently agitated. - .64 - (226) HEWER DEVELOPMENTS IN THE WASHING OF FRUIT. Md. State Hort. Soc. Proc. 33: 54-74. 1931. Md. Agr. Soc. Ann. Rpt. 15: 210-234. 1931, In most eastern fruit-growing sections 1 to 2 percent hydro- chloric acid "by volume is sufficiently strong for washing apples. The speed of washing can he increased "by heating the solution or by adding salt (8 Ids. per 100 gals.). The nost unsatisfactory feature of the fruit-washing problem is the corrosion and deterioration of the machinery under the influence of steam, acid, and salt. (227) CLEANING HEAVILY SPRAYED FRUIT. Md. Agr. Soc. Rpt. 18: 121-131. 1933. Any method which will satisfactorily reduce lead and fluorine will similarly reduce arsenic residue. Five types of washing equipment were used. The brush machine proved the most effective. The highest efficiency was obtained in the Pacific Northwest with the use of 1.5 percent hydrochloric acid, plus 2 percent salt, plus 1 percent light mineral oil at a tempera- ture of 100° F. (228) PROGRESS IN SPRAY RESIDUE REMOVAL. Ancr. Pomol. Soc. Proc. 50: 25-35. 1934. The experience of apple growers in the Pacific Northwest can be applied directly by the eastern apple industry with one exception. Alkaline solvents are not satisfactory for eastern use because the fungicides used, such as lime-sulphur, produce an alkaline residue. Reliance should be had on hydrochloric acid washes supplemented, if necessary, by heat to soften or melt the waxy deposits on the apple, salt to increase the ionization of the hydrochloric acid, detergents to render physical aid in the removal of foreign matter, increasing the time of ex- posure to the wash, and use of brushes or rubbing devices to pro- vide a scrubbing action. The importance of thorough rinsing must be emphasized. Ordinarily, apples, with the exception of Mcintosh and other tender varieties, can be washed in solutions heated to 110° F. if they are not exposed longer than 1 minute, while they can remain in a solution at 100° for 3 minutes without injury. Some suggestions are given to the fruit grower as to methods of sampling apples for analysis to obtain a representative sample. A number of charts show results of washing apples receiving various spray schedules. (229) HOT/ TO AVOID DAMAGE TO APPLES IN THE WASHING PROCESS. Md. Agr. Soc. Rpt. 19: 178-180. 1935. The chief danger of chemical injury to washed fruit - 65 - crises fron inadequate rinsing. The U. S. Department of Agriculture re cor.ner.ds that hydrochloric acid Washing solutions should he discarded and renewed after washing 1,000 to 1,200 hexes of apples' and 'that -copious quantities of fresh rinse water he applied, at least 3 gals, per bu. if possible. If the supply of rinsing water is limited, precautions against arsenical hurning can he taken "by using a line water rinse, — and BEEVES, E. L. (230) ARSENICAL AED OTHER EHUIT INJURIES OF APPLES RESULTING- FROI.i WASHING OPERATIONS. U. S. Dept. AgV, Tech. Bull. 245. 12 pp. 1931. Calyx scald is prinarily caused hy the presence of soluble arsenic on the apples. Its occurrence follows the use of either hydrochloric acid or alkaline solvents as washing naterials. Chenical injuries to apples fron hydro- chloric acid and alkaline solvents are described. The prevention of injuries fron these sources depends on adequate rinsing of the fruit. Where sufficient water is not available, the addition of line to the rinse water is beneficial. FLETCHER, S. "7. (231) OUR COiPSTITORS IN THE PACIFIC NORTHWEST. 'Mass. Fruit Growers Assoc, Inc., Rpt. of 34th Ann. Conv. 1928, pp. 170-193, Dry wiping machines, used in the Northwest in 1927 for the renoval of spray residue fron apples, inproved the appearance of the apples but renoved only one- third to one- half of the spray residue. Spraying the apples with 1 percent hydrochloric acid removes the spray residue but nay cause a browning or scald, especially at the calyx end. FORD, 0. IT. B and BURKHOLDER, C. L. (232) SPRAY RESIDUE AND ITS REMOVAL FRCI.I APPLES. Ind. Agr. Expt. Sta. Bull. 345. 18 pp. 1931. In the region of Indiana, 1 percent hydrochloric acid ^>y volume is a satisfactory solvent for the removal of arsenical residue- by the dipping method. Twenty to 30 seconds exposure to 1 percent acid in the flood type comnercial washer reduced the arsenical load below the world tolerance. The use of 2 and 4 percent acid in the dipping tank was not of sufficient added benefit as compared, with 1 percent solution to warrant its use, since it caused definite injury. The use of salt alone or in combination with any of the strengths of acid used was not of material benefit. The use of wipers or brashes failed to reduce the arsenical residue. The smaller the apples, i. e. , the more apples per pound, the higher the anount of residue is. - 66 * FREAR, D. E. H. , and WORTHLEY, Hi N. (233) REMOVAL OF SPRAT BE SI DUES FROM .APPLES, Pa. Agr. Expt. Sta. Bull. 318. 13 pp., illus. 1935. Tho satisfactory removal of lead presents a greater problem than that of arsenic, and certain conclusions based on studies of the arsenic removal alone do not meet present requirements. Hydrochloric acid, at 1 to 2 percent concentra- tion by weight (3 to 6 gals, 20° Be. per 100 gals.) should be used to secure maximum residue removal without injury to the fruit. One minute exposure to the acid in a flotation machine should be satisfactory in most cases. The necessary concentra- tion of acid depends on the amount of lead to be removed, the spray mixture employed, and the variety of fruit. The addition of wetting agents oi» salt to the hydrochloric acid solution has given no consistent benefit in the removal of lead from apples sprayed according to Pennsylvania recommendations. The use of wotting agents may be justified in other States where lead arsenate has been combined with or followed by mineral oil sprays. If apples are not cleaned satisfactorily with cold 2 percent hydrochloric acid solution, it is recommended that the tempera- ture of the bath be maintained at 100° F. Only when hydrochloric acid at 100° F. fails to give satisfactory residue removal, may the machinery be slowed down to give l-l/2 to 2 minutes exposure of the fruit to the acid solution. GREEK, F, M. (234) EFFECT OF ACID WASH ON THE KEEPING QUALITIES OF APPLES. A PRACTICAL HOME-MADE APPLE-W ASHING MACHINE. Colo. Agr. Expt. Sta. Bull. 343. 18 pp. , illus. 1928. Neither weak hydrochloric acid solutions aor cold sal soda solution affects the keeping quality of apples when properly handled, but the latter is not as efficient as the acid solution in removing the spray residue. Directions are given for building a home-made apple-washing machine. GRINER, J. I. (235) COST OF CLEANING FRUIT. Better Fruit 28 (4): 16. 1934. Hoosier Hort. 6 ('6): 87-89. 1934, Wash. State Hort. Assoc. Proc. 29: 97-99. 1934. Washing costs for a flood type machine wore 2.76 cents a box for acid and 2,77 cents a box for sodium silicate. In a flotation machine the cost was 1.66 cents. The cost to one organization of analyses and samples and of expense connected with washing averaged 2,10 cents a box in 1932 and 3.58 cents in 1933, - 67 - GROSS, C. R. , and FAHEY, J. E. (236) SOLE OF THE CEEI/IICAL PROBLEMS t& C0DLII7G MOTH COETROL. ITortbwsst Fruit Grower 2 (32-33) j 7, 22. 1S30. R. H. Reblinson found that the solvent action of hydrochloric acid upon lead arsenate was considerably increased by the addition of certain sulphates and chlorides, notably sodiun chlorite* The addition of kerosene caul si on (clay kaolin emulsifier) to hydrochloric acid facilitated the removal of lecd arsenate from waxy apples. HALLER, II. H. (237) SPRAY RESIDUE REIiOVAL. Mountaineer Grower 5(47): 6-14. 1934. Eastern-grown apples wpre satisfactorily cleaned of lead and arsenic residues by washing with cold 0.5 percent hydrochloric acid solution except when oil was added to the late sprays. The use of oil interfered with residue removal even when 1.5 percent acid was used, heated to 100° F. and with a wetting agent and salt added. Sodium silicate solution has been found unsatisfactory for cleaning eastern grown fruit. HALLER, I.I. H. , 3EAULI0iTT, J. H. , GROSS, C. R. , and RUSE, H. W. (238) SPRAY RESIDUE REMOVAL FRC1I APPLES. Lid. Agr. Expt. Sta. Bull. 363, pp. 121-136. 1934. "During the growing season, effective control of the codling moth rather than the avoidance of washing should be given first consideration. Results in the East indicate that apples receiving five or more cover sprays of lead arsenate and a fungicide or lime can be readily washed to comply with the tolerances, provided no oil is used in the late cover sprays. "with the fruit and solutions used in these tests, no particular advantage of any type of washing machine was apparent. Dry wiping or brushing machines were decidedly less effective than washing and can be used when the residues only slightly exceed the tolerances. "For apples that have been sprayed with lead arsenate and a fungicide without oil, a dilute solution of hydrochloric acid (0.5 percent by weight) at room temperature should be effective for washing the fruit. For fruit that is difficult to clean the efficiency of the washing solution can be in- creased by increasing the concentration of the acid to 1.5 percent "oy weight, by adding 1 to 2 percent of salt and 0.5 to 1 percent of a wetting agent or by heating the solution to 100° F. or by a combination of these. "Sodium silicate solutions arc relatively ineffective at room temperatures and, under eastern conditions, even - 68 - when heated are usually considerably less effective and more expensive than hydrochloric acid solutions. "Analyses of the washed fruit should he nade at intervals in order to determine whether the washing treatment used is effective or whether the efficiency of the washing process must be increased. "The storage quality of apples is not impaired by washing if properly done. Arsenical injury, which is the most likely form of washing injury to occur, may be avoided by thorough rinsing." — , BEAUMONT, J. H. , MURRAY, C* W. , and CASSIL, C. C. (239) LEAD RESIDUES AND THEIR REMOVAL AS INFLUENCED BY SPRAY PROGRAMS. Aner. Soc. Kort. Sci. Proc. 32: 179-182. 1934. Washing with 0.5 percent hydrochloric acid at room temperature reduced the lead residue below the tolerance (o,02 grain per lb.) on lots of Jonathan and Crimes Golden apples which had received 5 to 7 lead arsenate sprays, except when mineral oil had been used in the late cover sprays, and 1.5 percent acid at room temperature satisfactorily cleaned the latter. With 1.5 percent acid at 100° F. , Stayman Wine- saps and York Imperials which had received 5 and 7 sprays of lead arsenate with fish oil or casein-lime spreader in the second-brood cover sprays were cleaned to the tolerance. The addition of Vatsol was necessary to clean apples which received 7 lead arsenate sprays with mineral oil in the second-brood sprays. — - SMITH, E. , and EYALL, A. L. (240) SPRAY- RESIDUE REMOVAL FROM APPLES AND OTHER FRUITS. U. S. Dept. Agr. Farmers' Bull. 1752, 25 pp. 1935. Except for peaches, dry cleaning methods are not as effective as washing. Solutions of hydrochloric acid and sodium silicate have been found satisfactory for washing. Hydrochloric acid is particularly effective for alkaline residues, as when lime is added to the sprays, and is more effective against fluorine residues than are alkalin* washing materials. It may be used in either flood or flotation type washing machines* The concentration of acid used ranges from 0.5 to 1.5 percent. Its effectiveness mey be increased by increasing the concentration, raising the temperature of the solution, or adding fortifying materials, such as certain wetting agents or a very light mineral oil or odorless kerosene (1 gal. to 100 gals.), the latter only In heated solutions and flood type machines. The addition of 1 to 3 percent of common salfe has in many cases resulted in more thorough removal of arsenical residues, but it has little -effect 'on removal of lead and has an inhibiting effect on the removal of fluorine residues. - 69 - Sodium silicate solutions (commonly 60 to 100 l"bs. to 100 gals of water at 90° to 120 F. ) used in flood type machines are particularly suitable for f rui t that has not "been sprayed with line or other alkaline- materials, which has "been sprayed with an insecticide to which oil has "been added, or for fruit that has developed considerable wax. When thorough rinsing, careful handling of the fruit, and frequent changing of the washing solution are observed, the keeping quality of the fruit is not impaired. [This bulletin is a revision of U. S. Ecpt. Agr. Farmers' Bull. 168?. See No. 217], HARUAIT, S. W. (241) CODLING mm CONTROL. N. Y. State Agr. Expt. Sta. Bull. 627. 31 pp. , illus. 1933. With respect to difficulties with spray residue, 'the following points are noted: 1. Best results wore obtained whon fruit was cleaned within a short tine after picking. 2. Mechanical dry cleaners wore found suitable for the removal of residues below 0.02 grain. 3. Hydrochloric acid solution (l percent) used in washing machines successfully removed the heavier arsenical spray deposits from all parts of the surface of the fruit. 4. When heavily sprayed fruit or fruit that has developed con side rable wax is to be cleaned in cold weather, it may be necessary to heat the. washing solution to 80° to 100 F. A number of materials, including "barium fluosilicate, cryolite, manganese arsenate, calcium arsenate, nicotine tannate , and nicotine-oil sprays, have been tested as substitutes for lead arsenate. None, with the possible exception of calcium arsenate, has proved the equal of lead arsenate and furthermore, according to the latest rulings, all but the last two contain objectionable substances that would involve difficulty with spray residues. HARTIC-A1I, W. H. (242) THE SPEAY PROBLEM. Neb. State Hort. Soc. Ann. Hot, 60:33-41. 1931. Neb. Agr. Bd. Ann. Ept. 1931: 471-479. The toxicity of arsenic and lead is briefly discussed. Washing with hydrochloric acid is recommended. Of 42 lots of apples so treated, 41 met the domestic tolerance of 0.015 grain of arsenic trioxide per pound and 39 met the world tolerance of 0.01 grain per pound. - 70 - KASTLXT, H. (243) SPRAY RESIDUE EEviOVAfc IE RELATION TO THE KEEPIEG QUALITY OF APPLES AED PEAKS. Setter Fruit 22(12): 10-11, 28, 30, 36. 1328. Ho washing compound tested has proved superior to weak solutions of hydrochloric acid. Line in the rinsing liquid removes and neutralizes the acid quickly and completely "but it necessitates an additional spray of fresh water to prevent a slight white residue on the fruit, (244) THE REMOVAL OF SPRAY IS SI DUE FROIi APPLES AED PEARS.. PART II. EFFECTS OF SPRAY RESIDUE REMOVAL OH THE KEEPING QUALITY OF APPLES AED PEARS. Oreg. Agr. Sxpt. Sta. Bull. 234, pp. 23-36, illus. 1928. Cleaning "by mechanical means is apt to cause "bruising and stem punctures in pears and' to remove the "bloom from apples, causing excessive weight loss during storage. Washing, when properly done, results ir no serious injury to the fruit but rather increases its attractiveness. If the fruit is not thoroughly rinsed, injury from acid or soluble arsenic may occur. Deep submersion of open-cored frv.it results in in- jury due to penetration of the core. Calyx injury may "be caused by acid left oy improper rinsing or "by soluble arsenic which has been allowed to accumulate to too great an extent in the solution. Too prolonged exposure to the acid may result in burning the fruit. (245) SPRAY RESIDUE REMOVAL IE 1928. Better Fruit 23 (9): 13-14. 1929, Failure to clean below 0.01 grain of arsenious oxide per pound has usually been due to one of the following factors: (l) Excessive wax development, (2) coatings of dust and other foreign matter, (3) improper use of oil sprays. (4) excessive applications of arsenate of lead, (5) insufficient strength of washing solution, and (6) improper handling of washing equipment. The use of hydrated lime along with the sprays apparently facilitates somewhat the removal of arsenicals by the acid process. Heating the acid solutions to 95° to 100° F. increases the efficiency of cleaning. (246) THE REMOVAL OF SPRAY RESIDUE 3T THE WASHIEG METHOD. 111. State Hort. Soc. Trans. 63: 179-183. 1930. Hoosier Hort. 12: 158-162. 1930. The process of washing apples with hydrochloric acid - 71 - is described. A ir&ch solution containing 5 to 7 cts, of concentrated aci4 to 100 gals, of \?ater is |pjg£s?icient ancle ordinary circumstances. Late in the season it is sometimes necessary to increase the c orcertra.ti'Ui to 10 or 12 qts, per 100 cals. Diffuse ppray, flood wash, or flotation types of v^slers are successful,, Heep submersion types are unsatis- factory. Thirty to 40 seconds \rreatmert ia Usually sufficient in the first two types of machine, while 4 tc 5 nirntes are often required in the flotation type. Rinsing should be thorough. Hydrated line in the rinse water may be of -value, especially when abundant rinse -water is rot available. Thorough drying is not necessary. Washing should be done soon afte: picking. CHILD3, L. , and ROTIITSOh, R. E. (£47 OCCURRENCE AED PHEVSHTIOE 07 el L ill IITJUZY III 1FP1FS FROM THE HOOD RIVER YALIST. Orcg. Agr. Expt. Sta. Bull.. 242, 24 pp. , illus, 1929. Calyx injur; attributable to ihe was! i : process is duo primarily to arsenic rendered soluble by ta v shing cc ipounda or by prolonged exposure to moisture, . of the calyx pjury attributed in past years to washi , is appears t have occurred in the field prior to the washing tr i tment. Washing compounds, such as hydrochloric acicl, oodira carbonate, sodium hydroxide, and trisodium phosphate, whor. left in the calyces by them- selves, all produce physiological injur;-, but not of the common type, and it seldom results in decay. Arsuvi^als remaining in the calyces appoar to be a r.or n common cause of calyx injury in washed apples than arsenic accumulating with repeated ase of the solution. Eydrated lime used in the rinse bath is effective in reducing calyx injury when the acid process is used. '.Then properly done, washing tends to reduce calyx injury under Hood River conditions. — and R0BBTS017, R. E. '248) OFTTIhO RID OF SPJ1AY RESIDUE. Farm. Jour. CI (3): 26, 00. 1127. A report of work dono by tie Oregon Exp* riment Station on the removal of spray residue from apples and pears. WashJ with 0.25 to 2 percent hydrochloric c.riu is recommended. — and ROBHSOH, 0. Y. (249) TESTS SHJ'7 h0'7 TO PZhCVU SPRAY RESIDUE. Better Fruit 21 (7): 5-1, 16, 1927. iI°choni'"al cleaning of fruit was found unsatisfactory. The following materials were tested u washes for the remo\ r al of spray residue; Inorganic acids — hydrochloric, nitric, sulphuric, sulphurous, phosphoric, toric; baces — sodium hydroxide, potassium — ( cs~ hydroxide, sodium carbonate, sodium bicarboa&ts, calcium hydroxide, ammonium hydroxide , soda lime; salts — sodium chloride, potassium sodium thio sulphate, ammonium chloride, sodium "borate, copper sulphate, calcium sulphate, sodium chromate, sodium acetate, codium nitrate, calcium acid phosphate, calcium chloride; organic acids — malic, citric, tartaric, acetic, oxalic, tannic, carbonic; miscellaneous--cane su^er, glucose, alcohol, sodium stearate, sodium oleate, miscible oils, potassium benzene suiphonate. Of these, hydrochloric acid gave the best results. Used at con- centrations varying between 0.25 and 2 percant, it was very effective in the removal of spray residue and proved non- injurious to the fruit wncn properly used. In addition, it possesses many advantages; (l) It is comparatively cheap and cen. be obtained in large quantities* (2) It is effective at low temperatures. (3) It is a ncn-oxidizing compound end, there- fore, it not apt to causo discoloration, especially in injured tissue. (4) It is volatile and disappe-.rs of its own accord where rinsing has not been thoroughly done. (5) It is easily washed from the fruit after treatment. (6) It is not dis- agreeable to vork with. (7) It removes from the fruit rot only the arsenicals but also load, copper, and othar foims of residue. (8) It does practically no damage to the wax or protective covering, and loaves the fruit in a clean, attractive con- dition. A neutralizing bath is unnecessary unless efficient r i ns ing canno t be do ne . Kitric acid is efficient li the removal of residue and when properly used does not injure the fruit. However, it is more expensive, is an oxidizing agent, and is less volatile than hydrochloric acid. Acetic acid is inefficient except at high concentrations. Sulphuric acid removes the residue but in some cases may damage the fruit. Although be.se s in general tend to remove spray residue, sodium hydroxide (caustic soda) is the only basic compound discovered in these studies which successfully removes lead arsenate under all conditions. It is inferior to hydro- chloric acid in several ways. The efficiency or rate at which solvents remove spray residue is influenced by several factors, among which are (1) the concentration of the bath, (2) the temperature of the bath, and (3) the length of time that the fruit is sub- jected to treatment. These factors have about an equal effect. Agitation of the solution during treatment is very important. The use of oil or spreaders in lead arsenate sprays retards removal of the residue. Apples are more readily cleaned at picking time than after wax has developed. and EOBIwSOxC, H. H. (250) OBSERVATIONS ON SPRAY REMOVAL. Better Fruit 22 (8): 24, 57. 1928. ■73- jiory. '"/ashing with hydrochloric acid has usually been effective and added to the at tract iveness of the proauot. Washing machines employing the flotation, splash, spray, or sluicing systems have been satis- factory in most cases, Boideaax mixture used in combination with late sprays materially facilitates cleaning by the hydrochloric acid method. Lime (calcium carbonate) will proba^lv accomplish the same resents, formaldehyde used in the acid bath tends to keep it free from viable decay spores, plenty of fresh water should be us~d in rinsing. an i 2ELLS3, S. :... (251) THB REMOVAL CE SPRAY E^3 T EUE IROM ^JPPxES AND ?^S t PART III. DISIEFECTAKT5. Grey. Agr. Zxpt. Sta. Lull. 334, pp." .57-38. 1928. Results obtained o~ commercial lots of apples show 3.9 percent ieca" from all causes in the fruit washed with hydro- chloric a.cid al^ne and 3.8 percent decay in, the fruit washed with hydrccxilorie acid ar.a f onaal&ehyde . HAWKIUS, L. A. (252) SPRAY EESiEEE Rjii&^VAL BY LuiiaiANICAL El GDS IS SXIENSIV-alLY SES21D. Yt-arbook of Agr. 192&: 5( - ■ . Dry wiping is inefficient for removal of 3 ray residue from apples. Numerous washing sol\..tior±s were tried,! Ivlineral acids and alkalies dissolivj the arsenate residue, ml of t^eso hydrochloric acid and sodium carbonate, or mixtures of sodium carbo.iatvj and sodium hydroxide, are used most, the acid being used more than the alkalies. EiAEBEE, W. ?. (253) R£LX)VAL CP ZZ,^) ARSENATE FROM SFRAY2D FRUIT, Colo. Agr. Expt. Sta. Press Sail. 63. 4 pp. 192:. , /ashing of apples an a solution of 4 lbs. of rod°. ash end. 4 los. of table salt in 100 gals, of water at IOC P. for 10 minutes with gentle stirring, followed by rinsing, will remove lead arsenate residue. HEALjj, P. L. (254) ARSENICAL ENSIEUE OP aPPLES ANN PEARS, fash. Agr. 3: apt. Sta. Bull. 222 (Ann. Rpt. 37): 33-43. 1327. Dry wiping does not bring the arsenical residue down to 0.01 grain of arserious oxide ver pound of fruit except in early varieties or after light spray schelules. Chemical -74- washes have proved more effective and have 'oeen put into commercial use. Study has been made of different types of wet process machines employing "both alkaline and acid baths. NELLER, J. R. , and 0V2RLEY, F. L. (255) SPRAY RESIDUE REMOVAL PRO;,, WASHINGTON iiPPLES AND PEAttS DURING 1927 SEASON. . Better Fruit 22 (12): 15-17, 32. 1928. A summary of work presented in wash. Agr. Expt. Sta« Bull. 226(257). NELLER, J. R. , OVERLEY, P. L. , and DAM, H. J. (256) ARSENICA SPRAT RESIDUE AND ITS REMOVAL FROM APPLES. Wash. Agr. Expt. Sta. Bull. 213. 56 pp., illus. 1927. Dry wiping of apples to remove spray residue is not generally effective. The removal of ^rsenicrl residue from apples "by spr: y'.ng the apples on the trees with water or with water plus seme solvent has net been successful. Arsenical residue has not been removed to comply with the international tolerance by machine treatments in which a driving spray of water has been used, even though supplemented- by a brush wiper. Of the number ous solvents tested in bend wiping, soaking, or machine processes for the removal of arsenical residue, hydrochloric acid and nitric acid are the most potent at ordinary temperatures, the former being bettor suited to commercial use, being cheaper, less corrosive, end causing less injury to the fruit. (Vinegar, acetic and sulphurous acids, ammonia water, sodium hydroxide, borax, alcohol, and acetone were also tested.) Soaking apples for 10 minutes in 1 percent hydrochloric acid by volume followed by rinsing ir water is generally effective in reducing the arsenic to the international tolerance but it is too time-consuming and expensive. Hand brushing in 1 percent acid indicated that the time required for removal of the residue could be reduced to about 30 seconds at 65° to 75° F. Three types of machine devices for carrying out this process, using I or 2 per-' cent hydrochloric acid, gave promising results; (a) cylindrical rota-ting brushes in a vat of the acid solution, (b) a spray of acid from an overt- hanging perforated pipe forced on to the apples as they ere carried for- ward over spiral roller conveyors, and (c) a similar device with the spr£ from clipper nozzles. The pressure spray system is better then a wet brush process. The use of en oil spray appears to melee the removal of the arsenical residue by the acid process more difficult. NELLER, J. R. , OVERLEY, F. L. , RUEHLE, G. D. . and LUCE, V. A. (257) ARSENICAL SPRAY RESIDUE -AND ITS REMOVAL FROM iiPPL^S AND ?E.*RS. wash. Agr. Expt. Sta. Bull. 226. 100pp., illus. 1928. Averaging the results obtained with Jonatnan apples, 7 wet end 3 dry cleaning processes had the following order of decreasing effec- - 70 - tiveness: jet spray, fan spray, flotation and spray, flood wash, flo- tation and dip, "box din, flotation spray (alkali), vibrating bristle brushes, rotating bristle brushes, and rotating hemp brushes. The arsenical loads on'uncleanel lots of 11 varieties varied from 0,015 to 0.075 grai:- , with an average of 0.032 grain of arsenical trioxide ne: pound of fruit. The amount remaining after wet cleaning ranged from 0.0079 to 0.015 with an average of 0.011, ana after dry clearing from 0,021 to 0,027 with an average of 0,024 grain per pound. For the efficient cleaning of waxy varieties of apples, such as Winesap and Arkansas Black, using a fanlike spray of dilute hydrochloric acid, the temperature of the solution apparently should be close to 100 u F. In a jet sura;, machine ?. con- siderable loss in cleaning efficiency resulted from directing the spray up against the ^ovf~-r of the machi ». insi ad of directly against the fruit. On the average, fruit . Id -in colo. storage for four months before cleaning was not cleaned so well as portions o"^ the same lots cl L in i ne way at harvest tine. Small apples carried larger loads of arsenical residue per pound of fruit than large ap )ies, both before and after washing. The use of special "apple spray soap" applied six days before harvest did hot remove any of the arsenical residue nor make it any more easily renvoi hy dry or wet cleaning. Arsenical and acid burning of the core cells nay occur in fruits with an open calyx canal if a submersion process of cleaning is used. The importance of keeping down the spore content of the treat ing and rinsing baths is emphasized. The acid tanks and machines may be sterilized over night by the use of formaldehyde solution., 1 part to 8C0 of water for 10 to 12 hours being enough to free the machine completely of blue mold and other fungi. The use of 1:400 formaldehyde in the regular run would be equivalent to changing the solutions every 5 hours. Packing the - shed = ties while w t .. M d little if any effect in increasing the incidence of decay in cold storaje, while in common storage there was a slight increase in decay f ror: we t packing, HER33ET, J. W. (258) TH3 A3SEHA3S 0? LSAD SITUATION, Idaho State Hort. Assoc. Proc. 32: 53-59. 1927. A brief history of the situation. Wiping is inefficient in removing spray residue from fruit. There are two solvents [not named] satisfactory for washing. Hydrochloric acid solutions have been used successfully, HEDPJCX, j. P. (259) FIFTIETH AK3UAL E3P0HT. E. Y. Agr. Sxpt. Sta. Ann. Itpt. 50: 122. 1931. Washing machines using dilute hydrochloric acid as a washing solution were found to be very efficient in removing - 76 - arsenical residues fror. fruit. Conaorcial dry cleaners were less effective. BSHBT, A. M. (260) PEuOVAL 0? RhSITUAL POISOFS FROM FRUITS AND VEGETABLES. U. S. Patent 1,967,176, Issued July 17, 1934; applied for May 14, 1927; assign* d to U. S. Government and People of the United States. Residues of poisons such ?.s arsenical spra; s are removed by use of a dilute solution of a strong acid such as a 1 percent solution of sulphuric acid or hydrochloric acid, Alkali solutions also nay oc used. (261) PR0C3SS FOR THE REMOVAL OF RESIDUAL PCI SCOTS FRG.I FRUITS AHD VEGETABLES. U. S. patent 1,975,351; : ssued Oct. 2, 1934; applied for April 19, ] 92£ ; assigned to the Government and people of the United States. Residual poisons sua as these from the use of arsenical sprays a v, e removed fron fruits or vegetables such as grapes, apples, or pears 'oy the us^: of a dilute solution of an alkali such as a 1 percent solution of ammonia or sodium hydroxide. Other alkalies such as sodiura carbonate or sodium bicarbonate or mixtures of alkalies may be used. HERRICh", R. S. (262) REPORT OF SECRETARY-TREASURER. Iowa Yearbook of Agr, 1927. 616 pp. 1928. [pp. 242-245] E. L. Redfern recommends washing apples in 0.365 percent hydrochloric acid for 5 to 10 minutes to remove arsenic spray residues. This solution is made by mixing 1 gal. of commercial acid with 100 gals, of water. When this is sprayed on the fruit under 8 to 10 lbs. pressure for 30 seconds the aresenic is effectively removed. HOLLAUD, C. S. (263) SPRAY RESIDUE REhOVAL. Ohio State Hort. Soc. Proc. 54: 44-53. 1931. Washing of fruit with hydrochloric acid, 1 gal. of commercial acid to 99 gals, of water, is recommended fcr the removal of arsenical residue. (264) THE SPRAY PESIDUE SITUATION AS II FXISTS IK OHIO. Amer. Sue, Hort. Sci. Proc. 1930: 5-13-545. 1931. Of 73 samples of appl. s examined, only 1 had over - 77 - 0.015 grain of arsenic trioxide per pound. The use of hydrated line with line-sulfur and lead arsenate, as reconnended in the Ohio spray schedule for apples, tends to reduce the residue. Wiping removed 30 percent of the arsenical residue on Ohio apples. Hydrochloric acid at both 1 and 2 percent "by volume took off 80 percent of the residue on Wealthy apples which had an average of 0.025 grains r f arsenical residue. (265) REiiOVAL OF SPRAY RESIDUE JHOivi OHIO GROWN APFLES, Ohio Agr. Bxpt. Sta. Bino. Bull. 151: 123-129. 1931. Dry cleaning of fruit with commercial wiping machines v/ill remove 30 percent of the original arsenical residue and may be employed where the residue is between 0.01 and 0.015 grain per pound. The use of hydrochloric acid as a solvent for the residue was found very effective, removing 80 per- cent of tic original residue. Tests to determine the optimum strength of acid showed that 1 percent by volume of commercial acid for 3 minutes was the weakest effective solution. The type of washer to be used depends on the volume of fruit to be handled. Hand dipping is to be considered only if nothing else is available. For less than 6,000 bushels, a home-made flotation washer or a commercial machine without the dryer is recommended. Commercial washing machines can be used to advantage where over 6,000 bushels are handled. RORSFALL, J. L. , and JJtfNE, D. W. , Jr. (266) A DEFOAL'ING iviATERIAL FOR USE IN APPLE WASHING I.-iACHINSS. Jour. Econ. Ent. 27: 259-261. 1934. De Gras (wool grease) thinned with petroleum naphtha may be used to control excess foaming when Vat sol is used With certain washing confounds in commercial apple washing machines where agitation is present. HOUGH, W. S., and GROVES, A. B. (267) PROBLEMS AND EXPERIENCES IN REhOVING SPRAY RESIDUE FROM THE 1930 APPLE CROP. Md. Agr. Soc. Rpt. 15: 220-234. 1930. Wiping machines will not consistently remove more than 30 percent of the arsenic from apples. One minute in a bath containing 1 gal. of hydro- chloric acid to 100 gals, water removed 66 to 73 percent of the arsenical residue. Washing by dipping was efficient but is not recommended. Paddle washers gave considerable mechanical trouble. Commercial washing machines of both the jet spray and the flood types were satisfactory. - 78 - Increasing the acid concentration from 0.1 to 3.25 percent (from l/3 sal. to 10 gals, per 100 gals.) gradually increased the removal. According to best information the addition of acid "beyond 12 gals, in 100 gals, is not justified and some growers do not think it safe to use core than 4 gals." The limiting factor is not the strength of aq^d solution hut the amount of fresh rinse water used. — and GROVES, A. B. (238) PROBLEMS AITD EXPERIENCES IK REMOVING SPPAi RESIDUE FROM TEE 1930 APPLE CROP. Md. State H rt. Soc. Proc. 33: 74-82. 1931. Wiping machines are not dependable to remove more than 30 percent of the residue on apples. One minute immersion in a hath of dilute hydrochloric acid, 1 gal. to 100 gals., removed 66 to 73 percent of the arsenical residue. Dipping, paddle washers, and jet sr r"7 and flood type commercial machines were used satisfactorily . After the first w ck in October, when the temperature of the water fell to 62-72 P., 2 gals, of acid per IOC "la. of solution were used. The addition of 8 lbs, >f salt to 100 gaits, of solution in a commercial washer mded somewhat in reside removal from apples in cold storage. Heating the solution tc 100-110° P. also aided. In laboratory experiments using the dipping or flotation method, the addition of 1 percent of salt to the acid did not ■■ pear of practical value, HURT, R. K., S1LETT, ¥. B. , EHEART, J. R. , and (269) GROVES, A, P. REMOVAL OF SFP^Y RESIDUE PROIa APPLES, Va. Agr. Expt. Sta. Bull. 278. 16 pp. 1931. Three sprays of 3 lbs. of lead arsenate in 100 gals, of water applied in May and June did not necessitate removal of spray residue from the fruit at harvest time in September. An arsenical spray applied during the first half of July may leave excessive residue on the fruit if followed by dry weather for the remainder of the season.- An arsenical s ray applied late in July left an excessive residue for the remainder of the season, although rainfall greatly exceeded normal for Augast and. September. Approximately half the arsenical residue is distributed on the side of the apple, the rest being in the calyx and stem ends. Wiping or brushing the fruit removed, approximately one- third of the arsenical residue, on the average. Washing fruit in dilute hydrochloric acid consistently removed ex- cessive arsenical residn.es. One gallon of commercial acid (20° Be.) was usually used in 100 gals, of wash solution. n the day temperature dropped below 60 F. in October and whcr< the residue was considerably above the average, the strength of the solution was often increased to 2 gaJs. - 79 - of the ..cid in 100 gals, of rash solution. For each bushel of fruit, 1 gal. of fresh rinse water, delivered through spray- nozzles, removed traces of acid from the fruit. The towel ncthod of wiping and drying washed fruit was more satisfactory than air drying, "because the former removed leaf hopper specking and smears from fungicides or dust. Washed fruit kept as well as unwashed fruit when packed and stored in barrels or baskets. ISELY, D. (270) TIE SPRAY RESIDUE PROBLEM IK ARKANSAS. Ark. State Hort. Soc. Proc. Dec. 6-7, 1923, pp. 14-24. It has been generally agreed by all investigators that arsenical residue can be most satisfactorily removed by wash- ing fruit in dilute hydrochloric acid. The dosage usually recommended is 1 percent by volume. Wiping is not as efficient. Abundant rinse water, at least 3 gals, of fresh water for each box of fruit, should be used. If this amount of water is not available, the use of lime in the rinse water (2 lbs. of milk of lime to 100 gals, of water) is recommended. JARDLTE, J. T. (271) DIRECTOR'S BIEMIAL REPORT, 1926-1926. Ore.-. Agr. tot. Sta. , Director's Bienn. Rpt., 1926-1928. 133pp. 1928. The most outstanding accomplishment of the bi- ennium has been the development of a fairly satisfactory practical method for the removal of spray residue frcm fruit, washing with water solutions of hydrochloric acid. • • (272) DIRECTOR' S BISMIAL REPORT, 1923-1930. Oreg. Agr. Expt. Sta., Director's Bienn. Rpt. i 1928-1950. 143pp. 1S30. Calyx injury of apples by arsenic can be prevented by the following precautions? (l) K^ep the fruit dry after packing; (2) do not delay harvesting operations; (3) use lime or bordeaux mixture in late sprays; (4) wash as soon as possible; (5) use lire in the rinse bath. JEKKIITGS, 3. A. : ■' . (273) FRUIT WASHERS Ai T D SPRAY RESIDUE REuOVAl. Agr. Sr.gin. 15: 244-245, 243. 1934. Standard hydrochloric acid may be used in washing fruit that has beer, sprayed with lead arsenate. The temperature affects the efficiency of nearly all solutions. Apples can stand a temperature of 100° F. safely. In general, increasing the strength of acid increases the efficiency; however, there - 80 - is a. narked difference "between 1 percent and 0.5 percent. The safe limit is 1,5 percent, "out there is little difference Dctwcen a 1.5 percent and a 2 percent solution. Apples nay remain in thcs<- solutions 5 minutes as a maximum. Apples sprayed with oil sprays, apples with a very heavy residue, or apples from storage which have hecome waxy require a wetting agent in the hydrochloric acid hath. Sodium silicate and tri sodium phosphate were found ,iot to reduce lead sufficiently and also require a temperature of at least 80° F. JONES, F. S. (274) HEUOVIITG THE RESIDUE FROM APPLES AND PEARS. Amer. Fruit Grower 46 (7): 3-4, 20; 48 (8): 8-9. 1928. The first article outlines the introduction of acid washing methods aari descrihes three types of washing machines. The second discusses the c3.eani.ng solutions. Hydrochloric acid is the most practical. Five- tenths percent acid has usually been sufficient, although in particularly stubborn cases up to 1.5 percent was used. The use of minered oil in lead arsenate sprays makes cleaning more difficult, as does the development of wax in storage. josss, u. c. (275) TIE ARSENIC SPRAY RESIDUE SITUATION IN VIRGINIA IN 1930, and the part played BY DIVISION OF CHEivilSTRY in relieving THE SITUATION, IN CO-OPERuVTION NITH OTHER AGENCIES. Va. Dcpt. Agr. and Immigration Bull. 279: 28-30. 1931. The work of 'J. S. Hough on washing of apples with hydrochloric acid solutions is quoted. Of 5,159 samples of Virginia apples which were examined, 534, or 10.15 percent, ce/rried arsenic in excess of the foreign tolerance (0.01 grain arsenious oxide j^er pound) and 131, or 3.31 percent, exceeded the domestic tolerance ( . 015 g red n pc r p oun d ) . K., E. (276) REMOVING SPRAY RESIDUE, Aner. Agr. 130 (l): 6. 1933. Describes experiences of a commercial packer in wash- ing apples to remove arsenical residue, hashing with 1 to 3 percent hydrochloric acid is recommended. KADOY/, K. J. (277) (7ASHIHG RECOLiENDATIONS FOR ILLINOIS. 111. State Hort. Soc. Trans. 67: 269-275. 1934. The use of a flotation washing machine is reco - -mended. - 81 - Flood and spray type machines will not give satisfactory removal of high residue unless undent) rushes or a pro dip tank are used. Hydrochloric acid has "boon superior to sodiun silicate solutions. The solutions rocomr-onded for the various types of machines are: Flotation or hand dipping — 1.25 to 1,5 percent actual acid at about 100° F. , with about 1 percent of a wotting agent, for 2 1/2 minutes. Flood and spray type machines — 1.25 to 1.5 percent actual acid at 100° to 110° F. with wetting agent to give a good foan, tine as recommended by the manufacturer. Underbrush flood machines — 1,25 to 1,5 percent actual acid, heated to 100° to 110° F. when residue is high or fruit greasy, for 30 seconds, no wetting agent necessary, a predip in a good wetting agent being used if residtie and wax are both high. Rinsing should always be thorough. KENDALL, J. C. (278) AGRICULTURAL RESEARCH IN NEW HAMPSHIRE. N. H. Agr. Sxpt. Sta, Bull. 270. 27 pp. 1933. Only a few samples cf New Hampshire apples carried arsenical residue even slightly in excess of the tolerance in 1932 although it was an unusually dry season; Wiping appeared effective in reducing the spray residue but it is not recommended for apples carrying arsenic greatly in excess of the tolerance, (279) AGRICULTURAL RESEARCH IN NEW HAMPSHIRE. N. E. Agr, Sxpt. Sta. Bull, 280: 31. 1934. Running fruit containing excessive lead arsenate residue through a machine with brushes and two sets of polishing cloths aid not reduce the residue sufficiently. When run through a paddle type washer containing 2 parts by volume of hydro- chloric acid to 100 parts of water at 70° F. , both lead and arsenic were removed to a small fraction of the tolerance. KNIGHT, H. G. (230) REPORT OF THE CHIEF OF THE BUEZAU OF CHEMISTRY AND SOILS. U. S. Dcpt. Agr. 30 pp. 1928. As a result of excessive arsenic residue on apples shipped to England and other countries, the whole apple export industry was jeopardized. A cooperative investigation will "be undertaken "by the Bureau of Entomology, Bureau of Plant Industry, and Bureau of Chemistry and Soils to devise effective means for removing arsenical spray residue without injuring the apples. Effective substitutes for lead arsenate will also be sought. - 82 - (281) REFORT 0? THE CHIEF OF THE BUREAU OF CHEMISTRY AND SOILS. 36 pp. 1929. It has been found that the addition of certain salts, such as sodium chloride and sodium sulphate, greatly enhances the solvent action of hydrochloric acid for lead arsenate. (282) EFFORT OF THE CHIEF OF THE BUREAU OF CHEMISTRY AND SOILS. 57 pp. 1930. A portion of the hydrochloric acid in the usual acid wash may he advantageously substituted by sodium chloride, providing a cheaper wash and one less injurious to the fruit and machine ry. (283) REFORT OF THE CHIEF OF THE BUREAU OF CHEMISTRY AND SOILS. 78 pp. 1931. The quantity of arsenic left on apples by various spray treatments and the efficacy of numerous washing solutions in removing it under different conditions wore determined. A study of the effect of sprinkler irrigation showed that high sprinklers playing on the foliage tend to reduce the arsenic residue. Several hundred analyses for arsenic on tobacco were made and the residue per leaf found to range from 0.12 to 3.52 mg. of arsenic. (284) REFORT OF THE CHIEF OF THE BUREAU OF CHEMISTRY AND SOILS, 1933, 51 pp. 1933. Because of the establishment of a legal tolerance for load in foods, the solubilitjr of lead arsenate in many different solutions of acids, alkalies, and salts has been determined to aid. in selecting solutions which are capable of removing lead from apples. A new procedure was developed for the determination of lead in residues. Washing tests were made on various lots of fruit sprayed with •various combinations of lead arsenate, mineral oil, fish oil, and cryolite. The fruit had been stored at 50° and 100° F, and washed in a flood or brush type washer with hydrochloric acid, soda ash, or sodium silicate. No difference in the efficacy of the three solutions in removing arsenic could be detected with the fruit that had received cryolite and fish oil in the two final sprays. When mineral oil had been used throughout the season or in the final sprays, best - 83 - removal was obtained with soda ash. The arsenic in pi; in load arsenate was removed equally well with any of three washes. In general, truit held in cold storage was more easily cleaned thar. that he n d in common storage. (285) RHP0RT OF THE CHIEF OF TEE BUREAU OF CHEMISTS? AKD S0:^S, 1934* 54 pp. 193*. The most satisfactory procedures for washing apples were found to be hydrochloric acid olus mineral oil in a brush-flood machine and sodium silicate followed "by hydro- chloric acid in a double process machine. An investigation oT the solubility of cryolite in chemical solutions established that aluminum salts, ferric salts, and boric acid i; the presence of hydrochloric acid improve the solubility, whereas- sodium chloride and other sodium salts repress the solubility. LAUCKS, I. F. , RANKS, H. P., and R'FFFY , H, F. (236) :^THur OF CI3A1TIKG AED FKfcPAHING FOB STORAGE AED MARKET, FRUIT AFTER HARVESTING. U, S, patent 1,73*4., 316; issued October 22, 1929; applied for Oct. 11, 1926; assigned to Laucks laboratories, Inc. Fruit such as apples, pears, quinces, plums, prunes, oranges, grapefruit, lemons, etc., is washed with a 1 to 10 percent solution or" tris'oditan phosphate to remove spray residues of lead arsenate, calcium arsenate, bordeaux mixture, sulphur spray, mineral or vegetable oil sprays, etc. Alkaline salts of low alkalinity, e, g, , sodium borate and sodium otassium carbonates, may also be used in solutions of such strength as not to exceed the degree of alkalinity cf 10 percent trisodium phosphate. In general, this would include alkaline salt solutions having a nil of not greater than 13. LIPI.IAIT, J. a. (2 REPORT 01 TEE L:FFC:0F, a. J. Agr, Expt. Sta. Ann. Rot. 1928- 1929. np. 1-7.. 1930. Regardless of the quantity of lead arsenate applied, on fall and winter varieties of apples, whan sprays were not addad after July, arsenical "es^dups lid not exceed 0.01 grain of arsenic trioxide t>cr pound of fruit. Sprays applied later than July 1 resulted in heavier residues, when co ir er sprays later than July 1 are imperative, dust may la safely used. Laboratory and practical tests Lave shown that dilute hydro- chloric acid (0.3 to 1.25 percent) is the most efficient solvent for the removal of spray residues. For the grower Laving only a small lot of fruit to be cleaned, hand- dipping the fruit has been found practicable. - 84 - LIST, G. M. (288) A CHERRY TEST IN COLORADO. Colo. Agr. Expt. Sta. Bull. 385. 106 pp. , illus. 1932. Analyses made of cherries from experimental spray blocks to determine the amount of spray residue on harvested fruit showed that most of the samples carried more than the proposed tolerance of 0.01 grain of arsenic tri oxide per pound, one having 0.04 grain. The handling and washing of the fruit at the canning factories removes some of the residue. No samples of the canned cherries carried more than 0.01 grain per pound. The later applications left the most residue. It appears that three sprays can he used only on fruit that is to be carefully washed at the factory. Fruit to he sold fresh should not re- ceive more than the first two sprays and 1 lb. of lead arsenate to 50 gals, of water should be the maximum strength. There is little doubt that washing in dilute (1 percent) hydrochloric acid would remove the arsenic below the tolerance. This would probablv not be practical for cherries going to market as fresh f rait but could be developed for use in factories. LUTZ, J. M. , and EJMER, G. A. (289) STUDIES ON THE REMOVAL OE ARSENICAL STRAY RESIDUE EROM GRAPES. Amer. Goc. Hort. Soi. Proc. 1932: 345-349. 1933. Results of experiments indicate that grapes can be successfully washed in a juice plant for removal of arsenical residues in most cases with only slight modifications of present practices. As a wash solution, hydrochloric acid not stronger than 1 to 1.3 percent should be used and it should be followed by a water rinse. With grapes to be packed for shipment, it would be preferable to reduce the arsenical load below the tolerance by modification of the spray schedule. If this is impossible, grapes can be washed and shipped wet provided they are carefully handled and are packed in baskets of 12 qt. size or less. MAAS, A. R. (290) PROCESS OF REMOVING LEAD ARSENATE FROM FRUIT. U. S. patent 1,754,173. Issued Apr. 8, 1930; applied for Dec. 21, 1926. Lead arsenate spray residue is removed from apples, pears, etc., by washing or spraying the fruit with a solution of more than 1 lb. (preferably 3 to 5 lbs.) of sodium thiosulphate in a gallon of water for a period of 1 to 10 minutes. The ad- dition of soap or alkali will assist in wetting the fruit and •- vienetrating any oil present. Any thiosulphate capable of dis- solving lead arsenate may be used, e. g. , potassium, ammonium, or calcium thiosulphate, the proportion used being varied according - 85 - to the molecular weight. After this treatment the fruit is well washed with water and allowed to dry. McLEAN, H. C. (2S1) SOME RESULTS OF A STUDY OF SPRAY BE SI DUE ON APPLES IN 1927. N. J. State Hort. Soc. Proc. 1927: 213-225. Mechanical cleaning machines are unsatisfactory as re- movers of arsenical residues "because they cannot reach the stem and calyx cavities. The chemical removal of spray residues has "been investigated. Preliminary tests were made with washes of acetic acid, sodium hydroxide , and hydrochloric acid. The last gave the "best results. Laboratory tests show that hydrochloric acid in concentrations as low as 0.5- percent, with 5 minutes of contact, will remove arsenical residues satisfactorily, provid- ing the fruit is not too ripe and waxy, no matter whether dry mix or lime sulphur, Kay so or flour is used in the spray formula. (292) SOME FACTS ABOUT APPLE SPBAY RESIDUES. ■ N. J. Agr. 11 (4): 10. 1929. New Jersey experience indicates that dilute hydrochlor- ic acid (0.3 to 1.25 percent) is the most efficient solvent for the removal of spray residues. (293) EXPERIENCES WITH THE SPRAY RESIDUE PROBLEM. Del. Bd. Agr. Quar. Bull. 20 (5): 82-89. 1931. Washing of apples or pears with dilute hydrochloric acid has proved the most satisfactory method for the removal of spray residue. Two gallons of 20° Be. acid to 100 gals, of water was found necessary for varieties of apples maturing "before Wealthy, and 3 gals, of acid to 100 gals, of water for Wealthy and later varieties. The home-made paddle washer, the Bean chemical washer, and hand-dipping are suggested as methods of washing. (294) TEE NEW LEAD TOLERANCE AND HOW TO MET IT. Amer. Fruit Grower 53 (5): 7, 11. 1933. The use of a textile wetting or degumming agent such as Vatsol or Alkanol B in conjunction with the hydrochloric acid wash has "been found to greatly increase the efficiency of lead removal from oil-lead arsenate sprayed apples. The mixture used "by the New Jersey experiment station consists of 5 gals of 20° Be. hydrochloric acid and 8 lbs. of Vatsol to 100 gals, of - 86 - water. In the treatment of oil-lead arsenate sprayed but not excessively waxy fruit, Alkanol B proved a satisfactory substi- tute for Vatsol, when used at the rate of 4 lbs. of dry powder to 100 gals, of water. and WEBER, A. L. (295) USE OF WETTING OR DEGUMMING AGENTS IN THE REMOVAL OF STRAY RESIDUES FROM APPLES. Jour. Econ. Ent. 24: 1255-1261. 1931. Textile wetting or degumming agents used in conjunction with dilute hydrochloric acid or a mixture of dilute hydro- chloric acid and salt, will satisfactorily remove residue from New Jersey apples receiving heavy applications of oil and lead arsenate sprays. In most cases the application of heat to the cleaning solution was unnecessary. -- and WEBER, A. L. (296) MODERN METHODS OF REMOVING SPRAY RESIDUES FROM APPLES AND PEARS. N. J. Agr. Expt. Sta- Ext. Bull. 87. 24 pp., illus. 1931. The time of application of sprays has a more important bearing on residues than the quantity of spray material ap- plied. The relation of spray schedules to spray residues for varieties maturing at different dates is shown graphically- Considerable difficulty with residues may be experienced in orchards where early and late varieties of fruit are inter- planted, as the carrying over of sprays results. Rain may cause the accumulation of residues by gradual washing of spray material from upper portions of the trees. Present types of mechanical machines are unsuitable for removing spray residues. Washing methods using water as a solvent are but slightly more effective than is wiping or brushing. Removal of spray residues by washing with hydro- chloric acid has proved practical and economical. In gen- eral, the solutions should contain 0.63 or 0.95 percent acid (actual HC1) (2 or 3 gals, of 20° Be', acid to 100 gals, of water). Fruit may be cleaned in dilute acid by hand dipping, with a home-made paddle washer, or with one of several com- mercial chemical fruit washers, depending on the individual needs of the grower. Construction plans and directions for the operation of home-made washing equipment are given. and WEBER, A. L. (297) THE RESULTS OF STRAY RESIDUE STUDIES ON VEGETABLES IN 1932. N. J. State Hort. Soc. News 14: 490-491. 1933. It was found that high- residue cabbage and cauliflower would meet the market residue requirements if trimmed suf- - 87 - ficiently. Residue on canning tomatoes was satisfactorily re- moved with water "by the use of the usual washing equipment in two establishments. Removal of residue from heavily sprayed Early Red Pear tomatoes was possible "by submersion in 1 per- cent hydrochloric acid solution without injury to the fruit. The following precautions should he oh served to avoid heavy residues on vegetables: 1. Control insect pests, if possible, when the plants are small . 2. If late sprays or dusts are imperative, flour, lead arsenate, or bordeaux should not bo included in the mixtures. 3. In applying arsenicals to cauliflower after the flowers or head have commenced to form, protect the head in some manner. 4. Late sprayed or dusted cabbage should be trimmed to two loose leaves. 5. If necessary to control insects on celery after the plrnts have matured, use pyre thrum or some other material non- toxic to humans. — and WEBER, A. L. (298) CLEANING OF FRUIT CARRYING LEAD. Science 78: 579. 1933. Within the past two years the authors have developed a method of using a wetting or degumming agent of certain types with hydrochloric acid which, would enable fruit growers to re- duce the arsenic and lead residues on their produce to the required tolerance, kore recent experiments show that these wetting and degumming agents, when used with alkalies and alkaline silicates in heated solution, increase their effi- ciency to a marked degree. Eruit carrying lead 12 times the federal tolerance of 0.02 grain per pound' was satis- factorily cleaned with the silicate-wetting agent wash. and WEBER, A. L. (299) METHOD OF REMOVING SPRAY RESIDUE FROM FRUIT. U. S. patent 2,003,005. Issued May 28, 1935; applied for Oct. 27, 1933. Assigned to EndoT/ment Foundation. A method of washing fruit and the like to remove spray material from the surface thereof includes applying to the fruit solution containing about 1.0-2.0 percent of hydrochloric acid by weight, about 0.50-1.0 percent of a sulphonated aromatic hydro- carbon, and not over 0.5 percent of a substance adapted to prevent foaming of the solution. While a considerable number of sub- stances of various types may be used for this purpose, we find that substances taken from the following clrss, aliphatic ketones - 88 - and alcohols having from 6 to 10 carbon atoms, pine oil, fusel oil, degras, naphtha or mixtures thereof, usually in compara- tively small amounts, produce anti-foaming effects. and WEBER, A. L. (300) INFLUENCE OF SPRAY SCHEDULE AND OTHER FACTORS ON SPRAY RESIDUE REMOVAL. Jour. Econ. Ent. 27: 168-179. 1934. When oil is not used in combination with lead arsenate in the spray schedule, in addition to a casein or colloidal protein type spreader, all varieties of apples may "be sprayed up to time of harvest and the residues removed with cold hydrochloric acid. Varieties of apples maturing "before Wealthy may "be sprayed with the oil- lead arsenate combination 27, 37, 47, 57, and 67 days after petal-fall, using a non-casein spreader, and be satisfac- torily washed in any type of washer if a wetting agent (Vatsol) is added to the hydrochloric acid washing solution. Acid alone will successfully wash fruit where oil and lead arsenate are ap- plied no later than 57 days after petal-fall. Wealthy and later maturing varieties may be satisfactorily washed in hydrochloric acid alone if oil-lead arsenate sprays (3 qts. and 2 lbs. to 100 gals.) are applied no later than 57 days after petal-fall. Where similar applications are made 67 and 77 days after petal-fall, the addition of a special wetting agent to the acid is essential. Sat- isfactory washing may be accomplished at atmospheric temperature, although the operating speed of commercial washers may have to be reduced. Pre-dipping the fruit for l-l/2 minutes in a vat contain- ing the acid-wetting agent wash before passage through the commer- cial washer makes it possible to maintain the regular speed of the latter. The use of any later sprays of lead arsenate and oil in the concentrations stated above may necessitate heating the wash- ing solution. Applications of lead arsenate and non-casein spreaders without oil after the 67-days spray do not affect the above recom- mendations. and WEBER, A. L. (301) SPRAY RESIDUE REMOVAL FROM FRUITS AND VEGETABLES. N. J. Agr. Expt. Sta. Ext. Bull. 122.7 pp. 1934. This bulletin is a supplement to Extension Bulletin 87, which was issued before the Federal lead tolerance was promul- gated and before the use of oil-lead arsenate combinations for codling moth control had become general. In the absence of oil in the spray schedule, apples or pears may be easily washed with 1 to 1.5 percent hydrochloric acid as soon as they are harvested. Oil applied with lead ar- senate for second-brood codling moth may necessitate the use of a textile wetting or degumming agent in conjunction with the acid. In this process, 5 to 5-l/2 gals, of 20° Be. hydro- chloric acid and 2 to 8 lbs. of wetting or degumming agent are added to 100 gals, of water. When used in a commercial flood or spray type washer, the violent agitation of the solution causes excessive foaming. This can be controlled "by the addition of a defoaming agent, e. g. , a 50 percent solution of purified degras in purified naphtha used at the rate of 1 l/2 pints to 100 gals, of wash solution. This washing treatment has been most successful with the home-made flotation washer, exposing the fruit to the solution, at ordinary summer tempera- tures, for 1 l/2 to 2 l/2 minutes. In most flood or spray type commercial washers used in New Jersey, the fruit remains in contact with the wash solution for only 24 to 45 seconds. Under some conditions, with oil-lead arsenate sprayed apples, it is then necessary to heat the solution to 100 F. to remove lead residues. In many cases the necessity for heating has been eliminated by reducing the speed of the washer or by using a predip tank, in which case the fruit is washed for 1 1/2 to 2 1/2 minutes in the acid and wetting agent mixture, then passed through the commercial equipment for rinsing, polishing and drying. There is no Federal tolerance on copper residues, but in some cases enough bordeaux residues are left on produce to impart a disagreeable coppery taste. Such residues may be removed from grapes and small fruits, as well as beans and tomatoes, by dipping in acetic acid (l gal. of glacial acetic acid to 100 gals, of water) for 1 to 2 minutes, draining and rinsing. Hydrochloric acid will not remove bordeaux mixture. To remove arsenic from small fruits, beans or tomatoes, a solution of 3 gals, of 20° Be. hydrochloric acid in 100 gals, of water, in which the produce remains for 1 minute, is effective. It is not practical to subject such vegetables as cabbage and cauliflower to chemical washing. Because of the manner of growth of these vegetables, the problem may be solved by trimming. To avoid heavy residues which necessitate drastic trimming, control insect pests, if possible, when the plant is small. If necessary to control insects on vegetables, including celery, after plants are nearing maturity, use an insecticide non-toxic to humans. and WEBER, A. L. (302) HOW THE STATE OF NEW JERSEY MEETS THE SPRAY RESIDUE SITUATION. Del. Agr. Bd. Quar. Bull. 23 (5): 43-50. 1934. The New Jersey method of cleaning fruit employs the following mixture: 5 to 5-l/2 gals, of 20° Be. hydrochloric acid, 8 lbs. of Vat sol and 100 gals, of water. The efficiency of this depends somewhat on the type of washing machine used. The various types are briefly discussed. - 90 - MAGNESS, J. R. . , . • | .:••.••. ( 303 ) REMOVAL OF SPRAY " RESIDUE FROM 'APPLES AND'. PEARS. Idaho State Hort. Assoc. Proc. 32: 77-65* 1927.. Wiping of pears and' apples is unsatisfactory for removal of spray residue. Washing with hydrochloric acid has been, found most successful "by all' agencies conducting tests. Sodium hydroxide was found efficient "but.it .is harder to rinse from the fruit and more likely to bo injurious than hydrochloric acid. Nitric acid also 'proved generally satisfactory but it is more expensive, more corrosive and .more dangerous to handle than hydrochloric acid. The Colorado Experiment Station suggests the use of 4 percent soda ash and 4 percent ordinary salt solution at 100°F. One part commercial hydrochloric acid of 20° Be. by volume to 100 parts of water (0.365 percent KCl) is sufficient acid concentration to effectively remove lead arsenate residue from fruits. If an immersion system is used, 5 to 10 minutes is required. If acid jets are employed, the time is much shorter. Temperature control is not necessary. Thorough rinsing should follow. If an abundant supply of fresh water is not available, bicarbonate of soda may be added to the rinse in amount just sufficient to keep the solution from becoming acid. THE REMOVAL OF SPRAY RESIDUE FROM FRUIT. Bettor Fruit 22 (12): 7-8, 20. 1928. Dry cleaning is less satisfactory than washing. Hydro- chloric acid is suitable for cleaning. The concentration of acid required increases as the fruit becomes oily from stand- ing in storage. Concentrations up to 2 percent were used in 1927 on oily Wine sap and Arkansas Black apples without injury. Raising the temperature of the solution increases the rate of cleaning. Thorough rinsing is important. Alkaline solutions are equally as effective as acid in removing the spray residue. Solutions of soda ash are general- ly used when the residue is not too difficult to remove. With heavily sprayed lots, soda ash with sodium hydroxide or caustic soda of 0.25 t'o 0.5 percent strength was used. In commercial use of this method in 1927, borax was added to the washing solution in addition to soda ash and the solution was heated to 80° to 110° F. Coating the fruit subsequently with oil and paraffin prevents' shriveling due to attack of the natural wax by the alkali. (304) - 91 - (305) CLEANING T ''AXY OR OILY FRUIT. Better Fruit 22 (8): 20-21. 1928. Heat is necessary with "both acid and. alkaline washes for cleaning fruit which "becomes oily in storage. Temperatures up to 110° F. and acid concentrations of 5 percent did not injure Winesaps and Arkansas Slacks. — , BLACK, 0. F., and HALLER, M. H. (306) DIRECTIONS FOR USING HYDROCHLORIC ACID SOLUTION FOR REMOVING ARSENATE OF LEAD RESIDUE FROM APPLES AND PEARS. Bur. Plant Indus., U. S. Dept . Agr., Mimeographed report. Illus. 4 pp. (No date, "but issued 1926-1927.) Diagrams and brief directions are given for the con- struction of a washing tank and rinsing tank. As a wash solution, l/3 to l/2 percent actual hydrochloric acid (1 to 1 1/3 gals. 20° Be. acid to 100 gals, water) is satisfactory Thorough rinsing of the fruit crust follow the acid wash. If at least 2 gals, of water for each box of fruit is not avail- able for the rinsing tank, bicarbonate of soda must be used to keep the water from "becoming acid. , OVERLY, F. L., HEALD, F. D. , HELLER, J. R. , (307) FISHER, D. F., and DIEHL, H. C. THE REMOVAL OF SPRAY RESIDUE FROM APPLES AID PEARS IN WASHINGTON STATE. Wash. Agr. Expt. Sta. Pop. Bull. 142. 29 pp. , illus. 1928. The number and strength of lead arsenate sprays should be kept down to the minimum in order to reduce the amount of residue on the fruit at harvest time. Experience indicates that the use of casein spreader or oil with the arsenate of lead makes the residue slightly more difficult to remove chemically. Where hydrochloric acid is used as the cleaning agent, the use of lime with lead arsenate spray may have con- siderable merit . Three types of dry cleaning machines and eight types of washing machines are illustrated and discussed. In general, chemical' cleaning is more effective than dry cleaning methods. Hydrochloric acid can be used satisfactorily for washing apples to remove Iced arsenate residue and considerable fruit has been cleaned commercially by this method. The less agitation there is applied in the washing, the loss effective the cleaning is unless longer exposures are given. A driving jet of acid solution striking the fruit under considerable pressure proved very effective. The application of spray or flood wash without rotation of the fruit was slightly less effective than a - 92 - similar treatment with rotation. The system in which the fruit vras floated in the acid solution with sprays striking the fruit and driving it. forward generally involved an exposure to the acid of ah out 3 minutes. Fruit treated with a minimum of agitation, as when immersed in hoxes , can he efficiently cleaned only if rather long exposure is given. The strength of acid used varies With the condition of the fruit and the amount of residue. Fruit carrying not more than 0.03 to 0.04 grain of arsenious oxide per pound, "being treated immediately after harvest, can usually he cleaned satisfactorily \\rith a solution containing 1 gal. of commercial hydrochloric acid to 100 gals, of water (aoout 0.36 percent hy weight). After the fruit becomes oily as a result of standing in storage, the residue "becomes harder to remove and higher concentrations or higher temperatures or "both are necessary. After the fruit leaves the acid hath, it should be thoroughly rinsed, preferably with fresh running water. The following points are: important in avoiding injury of the fruit hy the acid wash! (l) Cleanliness of the hath; (2) reduced penetration of the acid hy avoiding submergence of the fruit as much as possihlc and avoiding a driving acid wash; and (3) thorough rinsing with fresh water. Where at least 3 gals, of fresh water for each box of fruit is not available, the use of lime in the rinso water is recommended. Alkaline solutions are as effective as hydrochloric acid in removing spray residue. A solution of 1 to 2 percent soda ash has been generally used when the residue was not too difficult to remove. With heavily sprayed lots, sodium hydroxide or caustic soda sufficient to make a 0.25 to 0.5 percent solution was also added. In commercial use of this method borax was used in addition to the soda ash and caustic soda and the solution was heated to 80° to 100° P. Alkaline solutions generally are more difficult to rinse from the fruit than are acid solutions. If the fruit is sound and rinsing is thorough, there is relatively little need for complete drying. MARSHALL, G. E. (308) 1934 C0DLI1TG MOTH SPRAY TESTS. Ind. Hort. Soc. Trans. 1934. 62-65. 1935. The same washing solutions and methods successfal in lead arsenate removal will not necessarily suffice for the cleaning of fruit sprayed with copper, zinc, fluorine, or other compounds having a tolerance set hy the U. S. Food and Drug Administration. Loads as high as 0.55 grain of lead per pound of fruit were encountered, and the removal in such cases was not entirely satisfactory with the host solutions known and the application of heat. Such loads were reduced, however, to 0.02 grain per pound. - 93 - IIARSEALL, R. E. (309) FRUIT WASHINGS-HOW AND ¥HEH7 Fruits and Gardens 28 (6): 5, 15. 1330. The situation in the Pacific Northwest is reviewed. Dilute hydrochloric acid, 5 to 7 quarts of concentrated acid to 100 gals, of water, is recommended for washing in nost cases, late in the season, it is sometimes necessary to use 10 or 12 quarts to ICO gals. Thorough rinsing is necessary. Hydrated lime is sometimes added to the rinse water, especially when water is not abundantly available for rinsing. Drying is accomplished oy blowers or to ,,r el drapers. UOOHG, E. C. (310) SPRAY RESIDUE Ai-ID THE PURE POOP LAW. Wash. State ~Hort. Assoc., Froc. 28th Ann. Meeting 1932: 128-131; Idaho State Hort. Assoc. Proc. 38: 107-111. 1933. Soda ash, crude alkali earths, sodium triphosphate, sodium metasilicate, ana other alkalies have been employed in place of hydrochloric acid for the removal of lead arsenate residues. All are less effective than hydrochloric acid for the removal of lead. The ultimate hope is to cortrol the pest in a way that will not render the product poisonou s to humans. The recent extensive use of fluorine compounds, which are now known to he highly toxic to man, has further complicated the situation. IiULVANY, H. A., and KELTEDY, H. E. (oil) PROCESS AND APPARATUS POP. CLEANING FRUIT. U. S. patent 1,916,633. Issued Julj 4, 1933; applied for September 23, 1329. A blast of material such ar sawdust is used to remove lead arsenate residue from fruit and to polish the fruit. KELLER, J. R. (312) SPRAY RESIDUE REI.10VAL EROh APPLES. Wash. State Hort. Assoc. Proc. 22: 28-36. 1926. In many cases dry wiping of apples will not reduce the arsenical residue to the desired level. Spreaders had ro effect on the case of removal. Oil in the spray schedule increased the difficulty of removing residues by dry wiping. A number of solutions were tested for the removal of arsenical residue by washing the fruit. Jonathan apples carrying an average load of 0,071 grain of arsenic triozide per pound were soaked for 5 minutes and brushed, for 20 seconds in water alone. - 94 - The residue was cut to 0.031 grain nor pound. Alcohol and acetone [in water] wore found ineffective. The alkalies such as ammonia and solium hydroxide did not renove as much of the residue ar the pelf's. Hitric, hydrochloric and sulphuric acids were about equally effective, much more so than acetic and su].phuious acids. The use of svlphuric and acetic acid: was discontinued because of observed injuries tc fruit in storage, hitric acid was known to be corrosive to machinery and operators, For the purposes desired, hydrochloric acid appeared to he the beet cheriic, 1 to use. Preliminary tests showed that a 1 percent solution of this acid at a temperature of 70° F. could ho expected to remove residues sufficiently by brushing the fruit in the solution for about 20 seconds. The type of washing machine used is described. A2SEJICAL FFSIDUS OF FFUIIS. Wash. Agr. Expt. Sta. Bull. (313) ?29 (Ann, Fcpt,):21. 1923. 7>' Tiie acid cleaning solution wa,c more effective on waxy apples when heated to abort 3.09° F. It vac not necessary to heat the solutions for cleaning h ajl arsenate residue from pears. A study of the 3tccumulatioi of arsenic in the cleaning solutions showed the importance of changing the solutions about once a day, Very waxy fruit ciuld 0' c leaned without harm if dinned in nontoxic wax solvents nrevfous to tne acid wash. (314) CHAHGES PFODUCFD IN APP1FS BY TEF USE OF CLFAFlhG- A1TD 01 L- COATIItfG PB0C3SS3S. Jour. Agr. Fes arch 36 : 429-431. 1928. Dipping in 2 percent hydrochloric ac:' d at 20° C. with mild .agitation for 10 minutes had little effect upon the subsequent rates of cither carbon dioxide respiration or loss in weight of Wine sap apples. Dipping in 2 percent sodium hydroxide under the sane conditions .affected respiration slightly and in- creased the rate of loss in weight. (315) KELIOVAL OF SPRAY HESIDUSS TBDu APPISS, A EAX SOLVES! METHOD. Indue, and Engin. Chem. 23:323-325. 1931. Hydrochloric acid is an effective cleaning agent for apple.- in most cases, but it sometimes fails with fruits that have ^oeen oil-sprayed or that have become waxy. It is shown that a thorough cleaning can be obtained by first dipping the apples in certain wax solvents, preferably methanol (acetone, petroleum ether and diacetone alcohol were e.lsc tested), after which an unheated hydrochloric acid wash is able to dissolve and remove practicably all the lead arsenate residue. - 35 - HEWC0II3R, P. J., and CARTER, R. H. (315) STUDIES OF JPEU0HI3E CO"I?OUiTDS FOR OOETBOLLIHG THE GODLIEG IiOSH. U. S. Dcpt. Agr. Tech. Bull. 373. 23 pp. 1353. Samples of Winosap apples sprayed with barium fluo silicate were taken "before and after each spraying and at harvest and analyzed for residues. Ho standard procedure was available , so a method was developed (E. E. Carter. Indus. Engin. Chem. , Anal. Ed. 3: 146-147). The results are given in mg. per apple and mg. ner sq. en. .and are compared with analyses for arsenic of apples sprayed throughout with lead arsenate. Tests were made to determine the feasibility of removing residues of barium fluosilicate from the fruit by means of chemical solvents. Starting with fruit with an average deposit of 0.04 grain of fluorine per lb. , treatment with 1 percent hydro- chloric acid, in a flood machine, at 75° F. reduced the load to 0.003 grain per lb., at 30° to 0.005 grain per lb., and at 110° to 0.005 grain per lb. Wasting with 1 percent sodium carbonate at 30° and 110° F. resulted in an average deposit of 0.014 grain per lb. Fruit that had been sprayed with cryolite was washed, after several months of storage, with 1.5 percent hydrochloric acid at 110° F. , with 5 percent sodium silicate at 120 F. , and with 13 percent sodium carbonate at 110° F. This fruit had a maximum deposit of 0.022 grain of fluorine per lb. before washing. Treatment with hydrochloric acid resulted in an average deposit of 0.004 grain per lb.; with sodium silicate, of 0.007 grain per lb.; and with sodium carbonate, of 0.015 grain per lb. 0VF3FI0LSFR, 2. L. , and 0VERLEY, F. L. (317) A EESUME OF SPRAY RESIDLE REMOVAL EXE32IEUGES IP TH3 STATP OF UASEIHGT01T. Better Fru.it 23 (l): 3-4, 15. 1334. With one snray program, certain lots of fruit with a light load of lead or arsenic are often more difficult to clean than fruit receiving another spray program and having a residue several times greater. Pher manganese arsenate sprays were used, hydrochloric acid was more satisfactory as a washing agent for arsenic removal before the wax formed on the fruit to any appreciable extent, but the lead was more satisfactorily removed with sodium silicate. Later in the season, after wax had developed, it was necessary, with fruit similarly sprayed, to use a tandem wash of hydrochloric acic 1 and sodium silicate to successfully reduce both the lead and the arsenic. When calcium arsenate combined with oils and spreaders was used throughout the season, hydrochloric acid was a more satis- factory wash than sodium silicate. Arsenic residue was effectively removed from Delicious apnles sprayed with zinc arsenate and - 96 - herring oil by either hydrochloric acid or sodiun silicate. The use of fluorire sprays in addition to load arsenate i in conpiration with ether materials, s,ccncd to increase the prohlop of removal of arsenic and lead. Tho use of fish oil in sprays tondod to increase the offoCtivoncss of sodium silicate in the removal of both irsenic and lead and did not generally make cleaning with hydrochloric acid nore difficult. Mineral oil caused 1 increased difficulty in cleaning with hydrochloric acid hut had little effect on cleaning with, sodium silicate. iJicotire sulphate and mineral oil coir.binatious x'or. roccnu-brood sprays following heavy applications of lead arsenate for first brood corrolicuted residue removal, but no more sc bhan mineral oil without ricotire. F5 su oil caused less difficulty than the mineral oil, especially when sodium silicate was used for wasim ng, Scan type spreaders added to the sprays increased the difficulty in cleaning with hydrochloric acid out facilitated cleaning with sodium silicate. Sodium silicate was more efficient at a wash at higher temperatures and lower concentrations than at higher concen- trations and lower temperatures, ^Yith this agent it was necessary to develop adequate foam, and soap was an excellent means for that purpose. Kerosene was satisfactory to control excessive foaming. Hydrochloric acid was more satisfactory than sodium silicate with fruit sprayed with manganese arsenate, calcium arsenate, .load arsenate-limc, or with early harvested and early washed iruit sprayed with lead, arsenate alone, T7ith fruit sprayed with lead arsenate and mineral oil, and early harvested and early washed, sodium silicate, in a suitable machine, was as effective as hydrochloric acid. With fruit sprayed with fish oil-lead arsenate and with lead arsenate- mineral oil, or with lead arsenate alone, harvested late and washed after wax ha.d developed, -sodium silicate with soap was superior to hydrochloric acid, Tandem washes were used with general success, — - OVEBLEY, F. L. , and ST. JOHE, J. L. (318) SOLE OBSERVATIONS COEGSBfflliKJ SPRAY PJ.SIEUE REhOVAL II: 1933, Wash. State Hort. Assoc. Proc. 23th Ann. Meeting 1933: 74-48, Hydrochloric acid is more satisfactory than sodium silicate for cleaning fruit sprayed with Hanganar (manganese arsenate), calcium arsenate, lead arsenate combined, with lime, or with early harvested and early washed fruit sprayed with lead arsenate alone. With fruit sprayed with lead arsenate and mineral oil, and early harvested and early washed, sodium silicate, when used in machines permitting its effective use, was equally as effective as hydrochloric acid. With all fruit sprayed with fish oil-lead arsenate and with fruit sprayed with lead arsenate alone, lead arsenate and mineral oil, harvested late and washed after wax had. developed, sodium silicate was superior to hydrochloric acid, When sodium silicate was used to remove fluorine sprays - 97 - from apples there was much less likelihood of injury from wash- ing than when hydrochloric acid was used. When tandem sprays arc used to clean fruit sprayed with fluorine compounds, it seems advisable, in order to minimize the danger of injury, to use sodium silicate ahead of the hydrochloric acid. When used to clean fruit sprayed with lead arsenate, excellent cleaning may result with either sequence. With waxy fruit sodium silicate may be most effective first, so that the wax will not seriously affect the acid. From the point of view of appearance and condition of the fruit after washing, however, it seems generally advisable, wherever feasible, to use the tandem sequence of hydrochloric acid first and sodium silicate last. 0V3PIZY, F. L. , and GAKVER, H. L. (319) RESIDUE ESI.IOVAL AND ITS RELATION TO THE SPRAY PROGRAM AND ORCHARD GROWING- CONDITIONS. Wash. State. Hort. Assoc, Proc. 28th' Ann. Meeting 1932: 89-101. Results of washing fruit with 1.5 percent hydrochloric acid, soda ash (50 and 75 lbs. per 100 gals.), tri sodium phosphate (50 and 75 lbs. per 100 gals.), and sodium silicate (50 and 75 lbs. per 100 gals.), all at 110° P., are reported. The acid gave about equal results with high and low lead arsenate spray programs, but with the alkaline solutions cither the con- centration or the' temperature had to be raised as the lead arsenate was increased in strength. When the amount of fish oil in combination with the lead arsenate was increased, the removal of arsenic with tri sodium phosphate and sodium silicate was improved, but with hydrochloric acid and soda ash it was more difficult. Fruit sprayed with mineral oil- lead arsenate combination was more difficult to clean than fruit sprayed with straight lead arsenate, especially when hydro- chloric acid was used for cleaning. Fish oil in the mineral oil-lead arsenate spray facilitated removal of arsenic with trisodium phosphate and sodium silicate. The addition of kerosene emulsion to the alkaline solution and a kerosene pre- spray in combination with the alkaline washes incre \sed the efficiency. The same pre- spray followed by acid caused a serious lentic :1 burning of the fruit. Only 3 out of 10 samples washed with 1.5 percent hydro- chloric acid at 110° P. were cleaned below the 0.01 grain tolerance. Soda ash at a concentration of 75 lbs. per 100 gals, at 110° P. is fairly satisfactory with the average sample, and is generally as effective as higher concentrations. Trisodium phosphate was the most efficient washing material when fresh solutions were used. In a range of 75 to 100 lbs. to 100 gals, the addition of 1 qt. of odorless kerosene facilitated cleaning. There is some question as to the length of time trisodium phosphate can be used as a wash. Every lot of fruit tested was satisfactorily cleaned with some concentration of sodium silicate at a certain temperature. - 98 - The amount of arsenate on the fruit at harvest tine is not a true criterion of difficulties that may "be en- countered in cleaning. It has generally "been found that where hydrochloric acid was used for arsenic removal, the longer the fruit was held in common storage, with the greater development of wax, the more difficult it would "be to wash. There is not much difference in the cleaning of fruit held in' common or cold storage when sodium silicate is used. Heat is necessary with the alkaline solutions. — and 'HELLER, J. R, (320) EXPERIENCE IF SPRAY RESIDUE REMOVAL. Wash. State Hort. Assoc. Proc. 23: 126-130. 1927. Spraying of apx)le trees with a water solution of lye and soap 5 to 7 days before harvest did not appreciably lower the -arisenieal residue at harvest time. In a comparison of acid and alkaline washing and dry wiping, . 1934. Wipers and brushes alone were not dependable for cleaning fruit carrying residues 1-1/2 times the tolerances. Apples which had received typical heavy spray schedules for western Now York were successfully cleaned with 1 percent of hydrochloric acid in various types of equipment when cleaning '."/as done at harvest time and residue removal was not complicated by waxinoss of the - 101 - fruit or "by late application of oil in the spray program. Apples receiving very heavy lead arsenate sprays late in the season were successfully cleaned in the "brush-type washer with 1.5 percent acid. The wetting agents found most effective in assisting in the cleaning of oil-lead- sprayed fruit were Grasselli W. A. Ho. 2, Vatsol, Lcthalate and Nckoo 3. Some injury to the skin in the calyx basin resulted from the use of acid-wetting agent solutions at high temperatures. An acid hath temperature of 90 to 95° F. is safe for Mcintosh apples, while other varieties may stand temperatures of 100 to 110° or rarely, 120°. Exposing apples to 1 to 1.5 percent con- centrations of acid longer than 5 minutes is likely to cause injury. The most important points to be observed in washing apples are as follows: The fruit should be washed at time of harvest. From 2 to 3 gallons of fresh rinse water per "bushel of fruit washed should be applied as a spray. The acid and rinse tanks should be cleaned and the liquid changed after every 1000 "bushels of fruit for a 100-gallon acid tank and after every 2Q0O bushels for a 200-gallon acid tank. Rotten apples should be kept out of the washer. PEITTZER, \7. T. (324) METHODS OF SPFAY RESIDUE REMOVAL. N. Y. State Hort. Soc, Proc. 79th Ann. Meeting 1934: 48-54. The following suggestions are made for fruit cleaning: (1) If the apples are only a few thousandths of a grain above tolerance when harvested, wiping or brushing may suffice. (2) For ordinary spray schedules, 1 percent of hydrochloric acid by weight should suffice to clean the fruit, (3) For fruit carrying heavy residues of straight lead arsenate, 5 or 6 times the lead tolerance, increase the acid concentration to 1.5 percent. (4) For fruit with residue complicated by late oil or oil-lead sprays, waxincss, or very heavy residue, the following is suggested: (a) Use of 1 percent Grasselli wetting agent No. 2 in flotation washer with 1.5 percent hydrochloric acid, preferably at 75-100° F. (b) Use of above in brush washer with anti-foam agent such o as Grasselli No. 16, warming solution to 75 F. (c) Use of warm solution of 1.5 percent hydrochloric acid (up to 100° F. ) with no wetting agent if fruit is not too difficult to clean. - 102 - (5) Clean fruit at time of harvest* (6) Use abundant rinse water, 2 gals, per bu. of fruit. (?) Change and clean tanks after 1,000 bu. are washed if tank capacity is 100 gals.; after 2,000 bu. if capacity is 200 gals. ■— MOORE, H. C, PALMER, J. C., and DAUGHTERS, J. T. (325) PRELIMINARY REPORT OH SPRAY RESIDUE REMOVAL INVESTIGATIONS— YAKIMA DISTRICT. Wish. State. Hort. Assoc. Proc. 23: 176-175. 1927. Waxy fruit from cold storage if; more easily cleaned of arsenical residue than, that fron common storage. On fruit that had been washed in a i.loe machine in 0.75 percent acid at C4° P. , 24 percent of the remaining arsenic was found to be in the cavities or about the stem, 13 percent in the calyx region and 63 percent on the surface. Seven gals, of acid to 100 gals, of water at 65° P. removed about as much arsenic as 3 gals, of acid to 100 at 85° F. .__ RYALL, A. L. , and DIEHL, H. C. (326) SPRAY RESIDUE REMOVAL IK IDAHO POR THE ]_928 SEASON. Idaho State Hort. Assoc. Proc. 34: 43-49. 1929. Wiping is unsatisfactory for residue removal. Washing With dilute acid is effective. Warming the acid increases the efficiency. Of v/ashed apples, 68.7 percent had less than 0.01 grain of arsenic per pound and only 4.2 percent had more than 0.02 grain per pound. Of wiped apples, 31.6 percent had less than 0.01 and 20.3 percent had more than 0.02. PERCIVAL, G. P., and POTTER, G. F. (327) SPRAY RESIDUE OH APPLES IE NEW HAMPSHIRE. Univ. H, H. Ext. Circ. 136. 4 pp. 1932. Chemical determinations have indicated that about half the arsenic is in the stem and blossom end cavities of the fruit where brushes or other dry cleaning equipment cannot reach it. Furthermore, polishing machines rub a portion of the arsenic into the wax instead of removing it. Hydrochloric acid is the most economical and efficient washing solution. The cheapest equipment consists of wooden tanks in which the apples arc submerged in open crates or pick hag baskets from which part of the slats have been removed. After standing for 3 to 5 minutes the fruit is drained and then dipped in tanks of rinsing water and finally rinsed with a spray or wash of clean water. Where the size of the crop justifies more investment, a home- made paddle washing machine may be constructed. Commercial washing machines are on the market which wash and rinse the applos and -then dry and polish them with toweling. - 103 - . PETTEY, F. W. (328) CONTROL OF CODLING MOTH. SOSDUING THE PEST AND REMOVING- SPRAY RESIDUE.. Farming in So. Africa 2: 145-146, 197 { 199. 1927. Dry wiping, dry "brushing, "brushing the calyx and wiping with a wet cloth, or washing with water and with solutions of hydrochloric acid considerably weaker than 0.5 percent actual acid would not "be sufficiently effective to reduce the arsenic in pears to less than 0.01 grain of arsenic trioxide per pound of fruit if heavy spraying were adopted. Sufficient arsenical residue can "be simply and economically removed from heavily sprayed pears "by dipping the fruit, placed in a large straw "basket, for 2 minutes up and down in a solution of 1 to 2 percent actual hydrochloric acid followed "by rinsing in water. (329) FURTHER EXPERIMENTS IN THE REMOVAL 0? SPRAY RESIDUE FROM FRUIT. So. African Fruit Grower 15 (l): 12-13. 1928. The concentration of hydrochloric acid in washing for spray residue removal must vary with the variety of apple, as some are more resistant than others to acid injury. Suitable concentrations and periods of treatments are given for a number of varieties. More varieties were resistant to injury for 3 minutes in 1 percent actual acid than 5 minutes in 0.5 percent. The addition of common salt to the acid bath will not prevent acid injury. The addition of bicarbonate of soda to the rinsing water will not prevent the typo of injury that results from too long a period of submergence in the acid solutions, but limited tests indicate the possibility that 1 lb. of bicarbonate of soda in 100 gals, of water in the rinsing trough will be useful in neutralizing a. certain amount of acid that accumulates in a limited amaint of still water. (330) REMOVAL OF SPRAY RES HUE FROM PEARS AND APPLES. A SUMMARY OF THE LATEST EXPERIMENTS. So. African Fruit Growers, Supplement, vol. 15, March 1928. 2 pp. Fruit growers who treat pears for residue removal in 1 per- cent hydrochloric acid, followed by ono-fourth minute draining, must allow at least 4 gals, of clean water for every lug box or bushel of fruit if wood-wool is placed in the bottom of each receptacle to avoid bruising, and at least 3 gals, of clean rinse water when wood-wool is omitted. More acid is tolerated (up to 1/15 percent) in the rinse water if the fruit is afterward drenched with clean water. The addition of bicarbonate of soda (1 lb. per 100 gals.) to the rinse water is advised where water is limited. - 104 - (331) REMOVAL OF SPRAY RESIDUE FROM PEARS AND APPLES. Farming in South Africa 3: 919. 1928. ■ The following results were obtained with Clapps pears sprayed 5 times with 1-1 /4 lbs. lead arsenate powder in 40 (imperial) gals, of water: Treatment Grains arsenic triozidc per lb. Untreated . 0.0296 Submerged 3 mins. in 1 percent actual HC1 0.0015 " 5 mins. in l/2 percent actual HC1 0.0064 " 1-1/2 mins. in 2 percent actual HC1 0.0012 (332) CODLING MOTH CONTROL AND REMOVAL OF SPRAY RESIDUE FROM FRUIT IN SOUTH AFRICA. 4th Intornat. Congr. Ent., Ithaca, Aug. 1928. Vol. II, Trans., pp. 382-388. 1929. With few exceptions, submergence of pears that had received 7 lead arsenate sprays (l-l/4 lbs. lead arsenate to 40 imperial gals, of water) for 2 minutes in 1 percent actual hydrochloric acid, draining l/2 to 2 minutes, and rinsing in plenty of practically clean water for 2 minutes at ordinary tap water temperature, would effectively remove arsenical spray residue from mature pears without causing any injury. Apples may be submerged 4 to 5 minutes in 1 percent acid if necessary, but this long period was usually unnecessary unless the fruit ha.d boon heavily sprayed or had been stored for some time and had accumulated wax, or unless the solution was considerably below 70° F. Submergence of pears for 2 minutes in 1 percent acid was generally more effective in the removal of visible spray stains than submergence for 5 minutes in 0.5 percent a.cid. (333) REMOVAL OF SPRAY RESIDUE FROM PEARS AND APPLES. Union So. Africa Dcpt . Agr. Bull. 63. 8 pp., illus. [1929?] Dipping or washing the fruit in 0.5 to 1 percent hydro- chloric acid, draining, a.nd rinsing in fresh water is the method recommended. If sufficient fresh rinse water is not available, bicarbonate of soda may be added to the rinse at the rate of l-l/4 lbs in 100 gals, to neutralize the a.cid. The addition of 2 lbs. of freshly slaked lime or hydratod lime to every 80 gals, of lead arsenate spray during the last two spray applications will facilitate the removal of the arsenate when harvested. - 105 - (334) REMOVAL OF SPRAY RESIDUE PROM APPLES. INVESTIGATIONS DURING 1929. Fuming in So. Africa 4: 433-185. 1929. Submergence of open-c-orcd r.pplcs in hydrochloric acid solution causes injur". The accumulation of free arsenic in the acid solution may also damage apples. Ono-galf percent acid at 85° P. will remove arsenate as well if not hotter than 1 percent acid at 60 ~ J P. l'ho addition of lime to lead arsenate sprays will facilitate the removal of arsenic "by acid treatment, as will also calcium cascinato spreader. (335) HEW METHODS POP. THE CONTROL OP CODLING MOTH. Union So. Africa Dept. Agr. Bull. 90. 10 pp., illus. 1930. The addition of summer r il to lead arsenate sprays, particularly the heavier gradoc, retards somewhat the removal of spray residue. To minimize this difficulty, oil with lead arsenate should he applied no later than 5 weeks "before the fruit is harvested, and calcium caseinate spreader at the rate of 1/2 Id, in 80 imperial gals, should never he omitted from any sprays after the first cover spray, if some are to contain oil. The same amount of spreader should he added when excess quantities of lead arsenate arc used in sprays to prevent thick "blotches, difficult to remove, from forming on the fruit. When fruits have a great excess of lead arsenate or have received several applications of oil, it should "be treated for 3 minutes in 1 percent acid at 80° to 90° P. Pruit should receive the last load arsenate spray not later than 3 weeks hefore ha.rvested. The substitution of nicotine sulphate and summer oil for some of the later arsenate sprays reduces the residue hut is expensive. (336) REMOVAL OP SPRAY RESIDUE PROM PEARS AHD APPLES. Farming in So. Africa 6: 441-442, 473-475. 1932. This is a. revised and enlarged version of bulletin No. 63 [Reference ho. 333], The use of 0.5 or 1 percent hydrochloric acid (l gal. commercial acid to 32 gals, water) is recommended. The use of a power washing machine is urged in preference to dipping in troughs. If the rinse water is limited, the fru.it should he dipped in 0.5 percent acid and "bicarbonate of soda added to the rinse water at the rate of 1 l/2 lbs. to 100 gals. Pruit should he washed as soon as harvested. The addition of a lime spreader to lead arsenate spray facilitates the removal of residue. - 106 - PLAHK, H. K. (337) REMOVAL OF SPRAY RESIDUE FROM CAMilTG PEACHES SPRAYED FOR PEACH TWIG BORER CONTROL. Calif. Dopt, Agr. Mo. Pull. £2:113-130. 115.ua. 1933, Tests are reported which sho™ that both tho lead and arsenic in load arsenate residue on canning peaches is ade- quately removed when tho peaches are peeled, washed, and canned according to the present accepted methods used "by the canning industry in California. PORTER, B. A. (353) THE PRESENT STATUS OP CODLING- MOTH COITTRCL. Ky. State Hort. Soc. Trans. 72: 131-143. 1927. hashing with dilute hydrochloric acid appears to he the most satisfactory method of residue removal. POTTS., E. C. (339) SPRAY LIMIT ORDER HJRTS GROWERS* Letter Fruit 21 (4): 11. 1926 An editorial. Careful wiping of pears unexpectedly failod to reduce ""he arsenic residue even near to 0.01 grain per pound of fruit* Washing with hydrochloric a?id at 1 to 2 percent (1 to 2 gals, per 100 gals, o^ water) is popularly recommended. PRICE, H. L. (340) RECENT DEVELOPMENTS II" THE VIRGINIA FRUIT GROWING PROGRAM. Amer. Fomol . Soc. Proe. 1929-1930: 53-69. 1930. W. 3. Ellett in 1926 demonstrated that 0.5 percent of hydrochloric acid followed hy thorough rinsing ooula he depended on to remove arsenic residue from fruit. REED, H. J., and HALL, H. G. (341) REPORT OF MOSES FELL A1TNEX FAP.M. Ind. Agr. Expt. Sta. Circ. 191. 19 pp. 1932. The use of 3 sprays of lead arsenate-fish oil against first-brood codling moth followed hy second-urood sprays of summer oil or summer oil and nicotine resulted in residue as high as on apples given 2 or 3 lead arsenate and lime sprays ■beginning July 1. Tests with various "ashing materials indicated the following points: The average arsenical removal secured amounted to two-thirds of the amoxnt present "before washing. .Increasing the strength of acid from 1.5 to 5 percent by volume failed to jnerease the efficiency of arsenic removal. The use of - 107 - hot 2 percent by volume hydrochloric acid did not increase the percentage of removal on most varieties. Cold sodium metasilicate was slightly less efficient than cold 2 or 3 percent hydrochloric acid "by volume. The addition of an ernulsifier to the sodium metasilicate slightly increased its efficiency. — and HALL, H. G. " (342) REPORT OF MOSES FELL ANNEX, FARM. Ind. Agr. Expt . Sta. Circ. 197. 11 pp. 1933. The average removal of arsenic from apples by a commercial washer using hydrochloric acid v/as 60 to 70 percent. The percentage removal of lead residue was about the same but there is usually 3 or more times as much lead as arsenic residue present The use of several soap emulsifiers with 2 percent by volume hydrochloric acid failed to increase the percentage removal over 2 percent. REGAN, W. S. (343) VALUES OF MOTH CONTROL SPRAYS TESTED. Better Fruit 21 (8): 16-18, 32-33. 1927. Chemical analyses were made of fruit sprayed in various ways to determine the effect of machine wiping on the removal of spray residue. The percentages of residue unremoved were as follows: I Percent Arsenate of lead alone ' 64 " " " and spreader 56 " " " , Volck and spreader 51 11 " " , Orthol-K and spreader 52 The author concludes that blotched arsenate of lead, i. Q. , without spreader, offers considerable difficulty in the removal of spray residue from the fruit. Oil spray [highly refined summer oil] over blotched arsenate of lead seems to interfere with cleaning the fruit. Oil spray over lead and spreader (Hercules) offers no difficulty. The combination spray of arsenate of lead, Volck or Orthol-K, and spreader gave relatively good results in the removal of spray residue by wiping, whereas the combination without spreader interfered with wiping. In general, wiping proved ineffective in the removal of spray residue down to tolerance requirements. The present drift of opinion is to a solution of the residue problem by means of a chemical wash. Should the chemical process prove out, it will mean that the grower can select the insecticide best suited to his needs and use as little or as much of it as he likes, with the assurance that the wash will satisfactorily remove it. - 108 - (344) OIL SPRAYS W THE "SIMMER PROGRAM. Better Fruit 22 (12): 9. 1928. An average difference of only 0.001 grain of lead arsenate residue per pound in the amount removed "by the hydrochloric acid wash was found "between apples sprayed four times with lead arsenate- oil- spreader combination ("both heavy and light oils) and fruit sprayed with lead arsenate and spreader. and DAVENPORT, A. B. (345) SOME RESULTS OP THREE YEARS' EXPERIENCE SEEKING BETTER CONTROL MEASURES FOR THE CODLING MOTH IN THE YAKIMA VALLEY. ttASH, Jour. Econ. Ent. 21: 330-537. 1928. Among the factors that interfere with the cleaning of residues from fruit "by machine wiping, where oil spray has "been applied, are (l) the use of certain types of spreader, which blotch the lead when lead and oil arc combined, (2) the use of oil and lead without sproader, (3) the application of oil over heavily blotched lead, (4) the use of inferior grade oil which may cause russeting or spotting of the fruit, thus setting the lead into the skin in these spots, and (5) the use of a heavy oil close to picking. In the case of the washing processes of spray residue removal the concensus of opinion is that oil sprayed fruit is somewhat more difficult to x^rash than fruit sprayed i^ith lead alone or with lead and spreader. Even here the difficulty is, in general, no greater than in the case of fruit upon which the natural wax has begun to form. The factors referred to as influencing the wiping procoss undoubtedly affect the washing process as well. With increased experience in the use of wash- ing solutions and machinery, oil sprays probably will offer no material difficulty in the cleaning of fruit. RICKS, G. L. (346) ARSENICAL RESIDUE REMOVAL TESTS. Michigan State Hort. Soc. Ann. Rpt. 61: 136-139. 1932. Washing with 3 percent hydrochloric acid at 60° P. and 10 percent of a commercial alkaline solvent, containing principally calcium carbonate, at 90° P., reduced the arsenical residue on apples sprayed with lead arsenate alone below the world tolerance, but neither solvent reduced the residue on fruit sprayed with lead arsenate and oil below 0.01 grain per pound. A brush type wiper removed about one-third of the original residue. Storage of apples made the removal of arsenical residue more difficult, especially when sprayed with a lead arsenate-oil combination. - 109 - ROARK, R. C. (347) INSECTICIDE RESIDUES REMOVED FROM FRUIT BY VARIOUS WASHES. Yearbook of Agr. 1928, pp. 389-390. 1929. The commercial apple-washing solutions in use are either hydrochloric acid or a dilute alkali. The- acid process, which is the more generally used, consists in subjecting the fruit to sprays of acidulated water (l to 3 gals, of hydro- chloric acid to 100 gals, water), rinsing in clear water, and removing excess moisture vdth an air "blast or towels. It has "been found that certain salts, notably Glauber's salt, common salt, copperas, and ferric chloride enhance the effec- tiveness of the acid in removing arsenical spray from apples and pears. (348) INSECTICIDES AND FUNGICIDES. Ann. Survey Arner. Chem. Vol. IV, chapter 29, pp. 358-382. 1930. The work of Ambruster (j. Franklin- Inst. 206: 597. 1928) Sarnes (Indus. Engin. Chera. 21: 172. 1929), Ginsburg (jour. Econ. Ent. 21: 588. 192 8), Robinson and Hartman (U.S. patent 1,708,330), Robinson (Indus. Engin. Chem. 21: 1132. 1929; Jour. Econ. Ent. 22: 693. 1929), Green (Colo. Agr. Expt . Sta. Bull. 343), the New York Agricultural Espcrimont Station (47th Ann. Rpt . 1928), Childs (4th Internat. Congress Ent., p. 675, 1929), Hamilton (jour. Econ. Ent. 22: 337. 1929), and Kuhn (ibid., p. 673. 1929) on spray residues is referred to. (349) INSECTICIDES AND FUNGICIDES. Ann. Survey Amcr. Chem. Vol. 5, chapter 26, pp. 398-421. 193l'. Reference is made to the work of Maas (U. S. Patent 1,754,173), Diehl, Ryall and Fancy (Northwest Fruit Grower 2 (35) t 8, 18. 1930), and' Gross and Fancy (ibid. 2 (32-33): 7, 22. 1930) on the removal of lead arsenate spray residue on fruit . (350) INSECTICIDES AND FUNGICIDES. Ann. Survey Amcr. Chem. Vol. VI, chapter 28, pp. 380-407. 1932. Reference is made to the work of Youdcn (Contrib. Boycc Thompson Inst. 3: 363. 1931) on errors in the Gutzcit method and to the work of McLean and Weber (jour. Econ. Ent. 24: 1255. 1931), Robinson (ibid. 24: 119. 1931), Nollcr (Ind. Eng. Chem. 23: 323. 1931), Fisher (Jour. Econ. Ent. 24: 526. 1931), Fisher and Reeves (U.S.Dopt. Agr. Tech. Bull. 245. - 110 - .1931), Heald and Ruehle (Wash. Col. Sta. Bull. 253. 1931), Ford and Burkholder (Purdue Univ. Agr. Expt . Sta. Bull. 345. 1931), Streeter, Chapman and Poarce (Jour. Econ. Ent . 24: 240. 1931), Holland (Ohio Agr. Expt. Sta. Bimo. Bull. 151: 123. 1931), Hodgkiss and Haley (jour. Econ. Ent. 24: 83. 1931), Hough (Ibid. 24: 327. 1931), and Carter (Ind. Eng. Chen., Anal. Ed. 3: 146. 1931) on spray residue removal. (351) INSECTICIDES AND FUNGICIDES. Ann. Survey. Amor. Chem. Vol. VIII, chapter 17, pp. 221-242. 1934. Reference is made to the work on spray residues and their removal reported by Marshall and Ford (Purdue Univ. Agr. Expt. Sta. Bull. 381. 1933), Harman (N. Y. Agr. Expt. Sta. Bull. 627. 1933), Uebstor (Jour. Econ. Ent. 26: 1016. 1933), Carter and Newcomer (Ibid. 26: 572. 1933), Myers et al. (Ind. Eng. Chem. 25: 624. 1933), White (ibid. 25: 621. 1933), Pahey (Proc. 28th Ann. Meeting V/ash. S^ate H rt. Assoc. 1932), Overley et al. (Wash. A s r. Expt. Sta. Bull. 286. 1933), Robinson (ind. Eng. Chem. 25: 616. 1933), and W c bcr and McLean (Jour. Econ. Ent. . 26: 727. 1933. and Sci. 78: 579. 1933). ROBINSON, R. H. (352) THE REMOVAL OF SPRAY RESIDUE FROM APPLES AND PEARS. PART I. CHEMICAL PHASES PERTAINING TO THE REMOVAL OF THE SPRAY RESIDUE " FROM APPLES AND PEARS. ' Oreg. Agr. Expt. Sta. Bull. 234, pp. 9- 22. 1928. Special conditions that make difficult the removal of lead arsenate spray residue by hydrochloric acid are: wax secretions on fruit in excessive amounts which coat the lead arsenate particles, oil spray that remains on the fruit at harvest and protects the residue from the solvent action, excessive spray deposits or large spots of residue, and deposits of dust, sand, and other air-borne particles on the spray residue.. Of these conditions, complications caused by dust deposits are the most difficult to overcome. The results of tests appear to indicate that the addition of hydrated lime or bordeaux mixture to lead arsenate sprays may facilitate the removal of the spray residue at harvest time. It must be noted that these materials are not soluble in soda ash and borax which are sometimes used for fruit washing. ' Acid between 90 and 950 F. .will remove residue more effectively than at lower temperatures. Very waxy, heavily sprayed fruit cannot be cleaned even by acid at 90° to 95° F. Cleaning by mechanical brushing or wiping is advisable only where very light spray programs have been followed. During most of the season the concentration of the acid bath should be 7 qts. of concentrated acid to 100 gals." of water, about 0.5 percent actual acid.' The fruit must be thoroughly rinsed. If very strong acid has been used, hydrated lime, calcium carbonate or sodium bicarbonate may be added to the rinse water. - Ill - (353) FACILITATOR* THE REMOVAL OF THE SPRAY RESIDUE. Jour. Econ. Ent. 22: 693-698. 1929. A "brief resume is given of conditions that prevent the effective removal of spray residue "by the chemical process. Of the factors retarding the solvent action, the settling of dust on the lead arsenate in the calyx and stem end of apples seems most difficult to overcome. In order to facilitate the removal of residue, numerous compounds were mixed with lead arsenate and applied to apples as a combination spray. The f raits sprayed v/ith the various combinations were then treated in acid to learn what materials aided the solvent action of the acid. In general, any compound or substance that is insoluble or only slightly soluble in water and yet very soluble in 0.5 percent hydrochloric acid will best facilitate the removal of the residue. Calcium carbonate, calcium hydrate and bordeaux mixture have these properties. For practical use, 1 or 2 lbs. of hydrated lime to each 100 gals, of lead arsenate spray should aid materially in the removal of the residue. (354) HEW S0LVE1ITS FOR 3iE R1I0 Tr AL OF ARSENICAL SPRAY RESIDUE. Indus, end Engin. Chcm. 21: 1132-1135. 1929. Aqueous solutions of the following compounds have been tested as solvents for load arsenate spray residue: hydrochloric acid, dibasic sodium phosphate, potassium chlorate, sodium chlorate, sodium chloride, ferric chloride, sodium fluoride, sodium sulphate, ferrous sulphate, magnesium sulphate, copper sulphate, sodium thiosulphate, nitric acid, sulphuric acid, sodium hydroxide and sodium carbonate. Combinations of hydrochloric acid v/ith the following substances wore also tested: sodium phosphate (dibasic and tribasic), potassium chlorate, sodium chloride, calcium chloride, ferric chloride, barium chloride, ammonium chloride, sodium fluoride, sodium sulphate, ferrous sulphate, copper sulphate, potassium alum, magnesium sulphate, nitric acid, and sulphuric acid. Uo one compound was found superior to hydrochloric acid for the removal of the spray residue. The combination of sodium sulphate and hydrochloric acid appears to be the most practical of those studied. (355) ORGAITIC SOLVENTS FOR AIDI1TG- THE REIOVAL OF SPRAY RESIDUE FROM WAXY OR OIL-COVERED FRUIT. Jour. Econ. Ent. 24: 119-125. 1931. Oil sprays and excessive wax formation on apples complicate the removal of spray residue. When certain organic solvents such as -..112 -. alcohol, benzol, acetone, oi] (viscosity 56) and Issrosene are added to the hydrochloric acid washing solution the residue is removed more effectively. Kerosene. .s^emo to ho the most practicable for this purpose. . . ; . (356) PROCESS FOR THE RMOVAL OF SPRAY RESIDUES FROM FRUITS AlTD VEG-STA3LES. .U. S. Patent 1,885,100. Issued Oct. 25, 1932; applied for July 11, 1929. Assigned to the United States Government and People of the United States. A process for the removal of spray residues of lead arsenate, calcium arsenate, bordeaux mixture, etc., from deciduous fruit and vegetables comprises the application to the fruit or vegetables of a water solution of a mixture of 0.1 to 1.0 percent hydrochloric acid and 0.25 to 2.0 percent of certain sulphates, e.g., ferrous sulphate, followed by washing with water and drying. (357) PROCESS FOR THE R3KOTAL OP SBLTUEAl OILS, WAX, AED SPRAY RESIDUES FROM FRUITS. U.S. patent 1,364,963. Issued Oct. 25, 1932; applied for Feb. 19, 1930. Assigned to the United States Government and People of the United Sta.tes. A pro.cess fqr the removal of natural oils, wax and spray residues, e.g., le>id arsenate and other anenicals, from apples and pears comprises the application to the fresh fruits of a solution of liquid petroleum hydrocarbons, hydrochloric acid and water, followed by washing vdth water to remove the cleaning solution and then drying the fruit. Solvents for the batural oil or wax of apples and pears and for residual oils from oil sprays are alcohols such as methyl and ethyl alcohol, glycerine and certain of the higher alcohols, acetone, benzol and its higher homologu.es, various hydrocarbons such as benzene, gasoline ard others of different hydrocarbon series, carbon tetrachloride, -commercial lacquer •solvents, sulphonated oils, chloroform, amyl acetate, carbon di- sulphide, ethe.r, alkalies, soaps, and various organic acids such as oleic. .Since some of these solvents are immiscible with a water solution of hydrochloric acid that is used in the washing process, it is necessary to emulsify them or to make combinations of two or more of the above specified solvents by which an emulsion is formed which can be dispersed through the hydrochloric acid solution. The process of the invention consists in adding any of the solvents or combination of solvents for wax or oil to the hydrochloric acid solution in the tank of the fru.it washing machine. (358) ARSEUICAL SPRAY RESIDUE OH CHERRIES. Or eg. Agr. Expt. Sta, Bull. 298. 15 pp. 1932. - 113 - The amount of arsenic found on cherries taken from 25 different orchards, in 1930 and 1931 varied from 0.003 to 0.069 grain of arsenious oxide per pound. That on cherries obtained from packing houses and canneries (18 samples) ranged from 0.002 to 0.035 grain per pound. Washing of cherries by dipping up and down in hydrochloric acid solution (3/4 pt . of commercial acid to 10 gals, of water) and then in fresh. water is tentatively recommended for the removal of residue. Repeated spraying of 2 cherry trees with water under 250 Ids. pressure resulted in reduction of the residue from 0.022 to 0.010 and from 0.027 to 0.009 grain of arsenious oxide per pound of cherries after 5 drenchings totaling 25 gals. The washing process employed by most canneries was effective in reducing the residue below the tolerance. (359) REMOVAL OF POISONOUS SPRAY RESIDUES ON FRUIT. Indus, and Engin. Chem. 25: 616-620. 1933. Severe infestations of insect pests and fungous diseases have required the application of abnormal amounts of toxic sprays in order to obtain effective control. Since cleaning sprayed fruit by mechanical moans proved futile, chemical solvents were tried. Dilute solutions of hydrochloric acid have proved effective and practical. Wax on apples, modified spray schedules and combination sprays of load arsenate and mineral or fish oils have created complications. However, the utilization of Other solvents, such as alkalies and mixtures of hydrochloric acid and kerosene emulsions, together with higher temperatures and improved washing equipment, have enabled the industry to over- come various difficulties as they have developed. (360) RECENT DEVELOPMENTS IN THE REMOVAL OF SPRAY RESIDUE. Oreg. State Hort. Assoc, 25th Ann. Rpt . 1933: 96-99. Wax deposits and oil sprays hinder the removal of lead residues from apples. Hydrochloric acid and sodium silicate are the only two solvents for lead residues which are worthy of recommendation. Hydrochloric acid is more rapid and is effective for washing easily cleaned fruit at lower temperatures (50° to 80° F.). At the higher temperatures (100° F. and above) it may cause fruit burn more readily than the silicate. Sodium silicate functions best at 100° F. or above. Apples carrying only about 0.12 grain of lead per pound, which have not developed much wax and have not received oil sprays, are effectively cleaned by either hydrochloric acid or sodium silicate. When acid is used as a solvent for apples difficult to cloan, it may be increased to 1.8 percent and heated to 100° F. If sodium silicate is employed, 30 lab. to 100 gals, of water may be used at about 110° F. or a little higher. The latter is superior for waxy and fish oil-sprayed apples. - 114 - The solvent (hydrochloric acid is "best) may he fortified with kerosene or light .petroleum oil (emulsified with kaolin or straight) or with salt for the worst lots of fruit. A tandem set-up, using sodium silicate (75 Ids.) at 110° F. in the first unit and 1.5 percent hydrochloric acid in the second has been employed. Some packing houses have also em- ployed a pre-dipping tank connected to a washing machine using acid. The materials in the pro-dip, depending on the condition of the apples, were (l) hot water* (2) kerosene or light petroleum oil (viscosity 55 or less) emulsified with kaolin (l gal. to 100 gals, water or 1 percent hydrochloric acid) j and (3) sodium silicate (25 lbs. to 75 Ids. in 100 gals of water). Vetting or degumming agents, such as Vatsol with hydrochloric acid, gave effective cleaning. ■ ( (361) SPEAY RESIDUE REMOVAL FROM WAXY FRUIT. Better Fruit 22 (12): 12. 1928. Warming the hydrochloric acid cleaning solution to 100° to 105o F. gave far "better results in removing arsenical residue from waxy fruit than treatment at ordinary temperatures. (362) LATEST DEVELOPMENTS IN WASHING APPLES. Jour. Econ. Ent . 27: 162-167. 1934. Same article condensed in Hoosier Hort. 16 (7): 102-107. 1934. Better Fruit 29: 3-9. July 1934. Heavy wax deposits on the surface of the apple make effective cleaning difficult. Oil sprays used in excess or applied too near harvest complicate spray residue removal. Foreign materials , such as dust and debris washed down from the limbs of the tree, insoluble spray materials, Luch ac sxilphur sprays, and peculiar calyx end forma- tions or roughness of the fruit may contribute to the difficulty of the washing process. Manufacturers of commercial washing machines have made im- provements each year and excellent equipment is now available. The most important requirement is that the washing solvents flood the fruit continuously. For ' fruit difficult to clean, rotating brushes increase the cleaning action materially. While many solvents have been tested for their selective ac- tion on lead, only two are worthy of general recommendation. These are hydrochloric acid and sodium silicate. When these solvents are fortified by such materials as kerosene or light oil, certain neutral salts, such as sodium chloride, and wetting or degumming agents, such as Vatsol, a more effective cleaning of apples has been obtained. - 115 - When fluorine compounds were used in only 2 or 3 sprays, either hydrochloric ..acid or sodium silicate cleaned the fruit effectively he- low the 0.01 grain tolerance. When used in combination with either mineral oil or fish oil in all cover sprays, it was not removed satis- factorily "by any cleaning treatment. — and HARTMAN, H. (363) THE XOiOVAL OF SPRAY, RESIDUE FROM APPLES AED PEARS. Wash. State Hort. Assoc. Proc. 22: 94-103. 1926. The removal of spray residue "by mechanical means has generally proved unsatisfactory and may result in injury to the fruit. Experiments were made with a number of washes or solvents for spray residue removal. Among the compounds tested were inorganic acids — hydrochloric, nitric, sulphuric, sulphurous, phosphoric, Doric; organic acid s — malic, citric, tartaric, acetic, oxalic, tannic, carbonic; bases — sodium hydroxide, potassium hydrox- ide, sodium carbonate, sodium bicarbonate, calcium hydroxide, ammonium hydroxide, soda line; salt_s-- sodium chloride, potas- sium chloride, sodium thiosulphate, ammonium chloride, sodium "borate, copper sulphate, calcium sulphate, sodium chromate, sodium acetate, sodium nitrate, calcium acid phosphate, calcium chloride; miscellaneous — cane sugar, glucose, alcohol, sodium stear ate, sodium oleate, miscible oils, potassium benzo sulphate ("benzenesulphonate) . Of these, hydrochloric acid was found the most satisfactory. When used at a concentration varying "between 0.25 and 2 percent (actual acid) it was very effective in removing spray residue and was also not injurious to the fruit when properly used. Sodium hydroxide was the only basic compound which successfully removed lead arsenate under all conditions and it was inferior to hydrochloric acid. It resulted in more injury to fruit, was harder to rinse off and will not remove copper and lime, as in bordeaux sprays. The rate of removal of sprey residue is affected by the concen- tration of the bath, the temperature of the oath and the length of time the fruit is treated. Agitation of the solution is important. The use of oil or spreaders in connection with lead arsenate retards removal of the residue. Apples at picking time respond much more readily to washing treatment than they do later on when wax development has taken place. and EARTMAU, H. (364) A PROGRESS REPORT Oil THE REMOVAL OP SPRAY RESIDUE PROM APPLES AND PEARS. Oreg. Agr. Expt. Sta. Bull. 226. 45 pp. 1927. The removal of spray residue has not been entirely satisfactory. Mechanical cleaning has resulted in injury to the fruit and mechanical devices may, in some cases, aid in the spread of decay organisms. Experiments with solvents have shown - 116 - that certain acids and "bases will remove spray residue with varying degrees of effectiveness. Of the compounds tested, none is superior to hydrochloric acid. When used at concen- trations varying "between 0.25 and 2 percent actual acid, this compound was found to remove 89 to 99 percent of the arsenical residue from apples and pears. It is also effective in removing lead, copper and lime and is practically non-injurious to the fruit when properly used. Other acids, such as nitric, acetic and sulphuric, are inferior to hydrochloric. Sodium hydroxide is the only "basic compound that successfully removed lead arsenate under all conditions. When used at ordinary temperatures and at the srme concentration, sodium hydroxide was no more efficient than hydrochloric acid in the removal of lead arsenate and was ineffective in removing copper and lime. Neutral salts such as sodium chloride and sodium thiosulphate are ineffective in the removal of spray residue when used alone. There was no advantage in adding nitric acid to the hydrochloric. The efficiency of solvents is affected "by the following factors: (l) The length of the treatment ,■ (2) the concentration of the solution, (o) the temperature of the solution, (4) the maturity of the fruit, (5) the amount of agitation given, and (6) the spray program followed. The use of oil sprays with arsenate of lead apparently retards the action of the solvents "but does not make cleaning "by this method impossible, provided a sufficient length of time has elapsed "between the application of the oil and the- date of treatment. The use of spreaders or deflocculants apparently does not interfere materially with the action of the solvent c. — and HARTMAN, H. (365) PROCESS FOR THE REMOVAL OF RESIDUAL POISONS FROM AND THE PRESER- VATION OF FRUITS. U. S. patent 1,708,330. Issued Apr. 9, 1929; applied for May 19, 1927. Assigned to United States Government and People of the U. S. Deciduous fruits are washed or sprayed with a 0.3 to 2 percent solution of hydrochloric acid to remove spray residues of arsenic, lead, copper and lime, after which they are washed with water and dried. To kill spores of "blue mold, gray mold, brown rot, anthracnose perennial canker, etc., the fruits are washed in a solution of 1 part of formaldehyde in 50 or 160 parts of water or acid solution, as the case may "be. — and HARTMAN, H. (366) REMOVAL OF SPRAY RESIDUE. Oreg. State Bd. Hort. Bien. Rpt . 19: 116-119. 1927. - This is an extract from Oreg. Agr. Expt. Sta. Bull. 226. (See reference No. 364). - 117 - and i/LTCHi M. B. . ■ (367) THE REMOVAL OF IE AD AND ARSENIC SPRAY RESIDUES EROM APPLES AND PEARS. Oreg» Agr. Expt . Sta. Bull, 317. 15pp. 1933. "Both lead and arsenic .nay "be removed effectively below the established tolerances "by washing either in a solution of hydrochloric acid or sodium silicate. The concentration, temperature, and time in either of these solvents must "be regulated depending upon the amount of oil or wax present on the fruit that makes cleaning especially difficult. Most varieties of apples and pears harvested at the proper time of maturity and washed immediately after picking and before excess wax forms, may be effectively cleaned without the aid 1 of heat, providing no late oil- sprays have been applied. When ex- cessive accumulations of wax are present or late oil sprays have been applied, it may require unusual washing treatment, such as the double process wash, the use of de gumming agents, etc., together with es- pecially adapted machinery, to clean the lead effectively below the tolerance. All lots of fruit tested, including very waxy, heavily sprayed samples, were veil cleaned "below both the lead and arsenic tolerances "by cleaning with a "double process" consisting of passing the fruit first through a washing unit containing sodium silicate and then through a hydrochloric acid wash. For fruit difficult to clean, underneath brushes revolving at the rate of 125 r.p.m. were found superior to the overhead flood type machine. Washing or de gumming agents used in comhination with hydrochloric acid aid materially in cleaning heavily sprayed, waxy fruit. Experimental tests indicate that the following treatments and modifications may improve the cleaning action: (a) Sawdust used in either the hydro- chloric acid solution or the sodium silicate solvent produces a slight cleaning effect, (b) Either sodium chloride or sodium nitrate used at the rate of 16 pounds to the hundred has oeen found beneficial as a supplement to hydrochloric acid heated to 90° F. or above, (c) Cold, waxy fruit, chilled "by standing in the orchard or ware- house or removed from cold storage, may be more easily cleaned if warmed by floating in a predip maintained at 110° F. before passing into the solvent." (Prom author's abstract.) RUNNER, G. A. (363) CONTROLLING GRAPE INSECTS AND THE PRESENT SITUATION REGARDING AR- SENICAL RESIDUE. Ohio State H rt. Soc. , Proc. 65th Ann. Meeting, p. 206-211. 1952. In spraying grapes, an adhesive, such as fish oil or resin fish oil soap, is necessary in the mixture to secure adequate cover- ing of the berries and retention of the arsenical. This compli- cates the cleaning problem, since residue removal is made more difficult. Until an insecticide is found which controls the grape berry moth and leaves no objectionable residue, the situation, when late sprays are necessary, may be met in some measure by wash- ing. This involves dipping the grapes in arsenic solvents, a? for apples j but is more difficult as grapes are highly perish- - 118 - able. Experimental work has not reached the point where a prac- tical or easily applied method of residue removal can he recom- mended. The most encouraging prospect is utilization of cultural methods to reduce the infestation to the point where one thorough application of lead arsenate just after the fruit has set will give satisfactory control. RUTH, \L A. (369) IMPORTANT FACTORS INVOLVED IN SPRAY RESIDUE REMOVAL. 111. State Hort. Soc. Trans. 67: 257-268. 1924. The results of experiments in washing apples which had re- ceived seven lead arsenate sprays, all "but the calyx spray con- taining oil (Dendrol) , are reported. Pour and one-half gallons of 28 percent hydrochloric acid in 100 gallons was used in the washing solution. The addition of wetting agents to the acid did not increase the efficiency of residue removal vihen used in a brvsh washing machine. In a flotation machine, the addition of Vatsol improved removal. Large quantities of wetting agent with a dofoamer were no more effective than small quantities without the dofoamer in the brush machine. Predipping the fruit in a wetting agent before running through the brush machine at 110° P. had no particular effect, but predipping was very effective when the washing solution was colder (70°). Washing by flotation was superior to the brush machine in residue removal, apparently be- cause of the difference in time in the solutions, but the apples did not look as well. Samples of apples were washed 10 days be- fore normal harvest, at normal harvest, and 10 days after. The load of arsenic varied little over the 20-day period but the load of lead on the unwashed apples decreased materially. Arsenic re- moval was not as easy 10 days before harvest as at normal harvest. About the same proportion of lead was removed by washing at each harvest period. About six times as much arsenic and lead were left on the apples after washing at 65° as at 110°. RYALL, A. L. (370) RECENT EXPERIMENTAL tfCHX Or TEE REMOVAL OP LEAD ARSENATE AND FLUORINE RESIDUE FROM APPLES. Better Fruit 29 (4): 3-4. 1934. Lead residue on fruit sprayed throughout the season with lead arsenate, alone or with spreader, was usually removed readily to meet the tolerance, while on fruit sprayed throughout the season with lead arsenate and mineral oil or with mineral oil in combina- tion with other materials for second-brood sprays it was generally difficult to remove satisfactorily. Arsenical residues on fruit sprayed throughout the season wjfch calcium or manganese arsenate plus mineral oil in several cover sprays were removed without difficulty by acid washing treatments but were not satisfactorily ranoved by sodium silicate. The lead and fluorine residues on fruit sprayed in the first brood with lead arsenate and in the second brood with 2 or 3 covers of cryolite plus fish oil or mineral oil - 119 - were satisfactorily removed when the "better types of washing treatments for these residues were employed. The fluorine ' residues on fruit sprayed with cryolite plus fish oil or "barium fluosilicate plus fish oil for 6 cover sprays throughout the season, were practically impossible to remove to meet the fluorine tolerance. Five types of fruit washers were studied:, (l) The common flood machine v/ith walk along conveyor, (S) the brush-flood machine v/ith underneath transverse, rotary, rubber-covere I brushes in the wash compartment, (3) the flotation machine with slowly re- volving paddles to convey the fruit through the solution, (4) the prodip machine which is a combination of flotation machine and or- dinary flood machine without a rinse between the two washes, (5) the double process which consists of 2 flood machines in tandem with 2 washes and 2 rinses. The most efficient were (5) and (2). In types (l) and (2). the addition of non-emulsified light mineral oil to the hydrochloric acid and salt combination increased the efficiency of removal of lead, arsenic and fluorine residues. Light mineral oil proved superior to medium oil, kerosene, acid stable light oil emulsion or acid stable kerosene emulsion. Sodium silicate at 110° to 120° F, is more efficient in tynes (l) and (2) than hydrochloric acid and salt at 100° to 110° F. In (l) the use of a \-;etting agent with hydrochloric acid and a vool grease-kerosene defoamer brought about more complete removal of lead ^nd arsenic than any other combination of solvents used in that machine bat it did not prove effective as a solvent for fluorine. In (.3) the addition of a wetting agent to the hydro- chloric ncid solution very materially increased the effectiveness for lea.d and arsenic removal. Boric acid added to hydrochloric acid solution apparently increased the effectiveness for Loth lead and fluorine removal. Sulphuric acid brought about practically the same removal of fluorine residues as hydrochloric acid but is not recommended. Phenoldisulphonic acid showed no promise for either lead or fluorine removal. md FAHEY, J. S. (37l) THE EFFECT OF FISH OIL SPRAYS ON SPRAY RESIDUE REMOVAL. (A pre- liminary report.) Northwest Fruit Grower 4 (8): 4. 1932. Certain alkaline solutions, namely sodium carbonate (50 and 80 lbs. per 100 gals.), trisodium phosphate (80 lbs. per 100 gals.), and a mixture of 75 pprcent sodium carbonate and 25 percent sodium borate (60 and 80 lbs. per 100 gals.), at 90° to 100° F., used in efficient fruit washers, gave satisfactory re- moval of arsenical residue from fruit sprayed with fish oil and lead arsenate. Hydrochloric acid, when used in 1 percent (by weight) concentration or with l-l/2 percent kerosene emulsion at 110° F. , did not give satisfactory removal of arsenical residue from such fruit. - 120 - RYERSON, K. i.. (372) REPORT OF THE CHIEF OF THE BUREAU OF PLANT INDUSTRY, 1934. 36 pp. 1934. The most satisfactory treatments for removal of lead and fluorine residues were (l) l-l/2 percent hydrochloric acid plus 2 percent salt plus 1 percent light mineral oil at 100° to 110° F. , in a "brush-flood machine, and (2) sodium silicate 70 pounds to 100 gallons of water at 110° with enough soap to produce a foam, followed "by l-l/2 percent hydrochloric acid at 100° in a double- process machine . No washing method was found to he effective when cryolite or other fluorine sprays had "been used in more than the last 2 or 3 cover sprays. SEARS, E. M. (373) METHOD OF REMOVING RESIDUAL POISONS FROM FRUIT. U. S. patent 1,624:074. Issued April 12, 1927; applied for October 21, 1926. lead arsenate spray residue is removed from fruit "by dipping it first in mineral, animal or vegetable oil containing from one- half of 1 percent to 99 percent of fatty acid, or in fatty acid containing from 1 percent to 99 percent of mineral, animal or vegetable oil, the re id rendering the oil soluble in water. The fruit is than dipped in a solution of water made alkaline with 1 to 10 percent of soda, alkali or ammonia, after which it is washed in clear water. Suitable oils are vegetable oils, corn oil, cottonseed oil, sulphonated oil; mineral oils, paraffin oil and crystal slab oil; animal oils, sperm oil and fish oil. Suitable fatty acids are oleic, stearic and coco fatty acids. SHARMA, J. N. (374) PROCESS OF TREATING FRUIT TO REMOVE SPFAY RESIDUES. U. S. patent 1,875,944. Issued Sept. 6, 1932; applied for June 9, 1931. Assigned to Food Machinery Corp. A process of treating fruit, such as apples, to remove spray residues, such as lead arsenate compounds, comprises con- tacting the fruit with a solution of alkali silicate capable of forming oxytriarsenate with the lead arsenate of the residue. There is no particular advantage in heating the solution. A 2 percent solution gives satisfactory results. SHEAR, E. V., Jr. (375) REMOVING SPRAY RESIDUE FROM FRUIT. N. Y. State H rt. Soc, Proc. 72nd Ann. Meeting, pp. 149-151. 1927. Hydrochloric acid, 1:500, was used as a wash for removing spray residue from apples. - 121 - SHEAR, E. V. . . (376) WASHING FRUIT TO REMOVE SPRAY RESIDUE IN THE HUDSON VALLEY. N. Y. State Agr.. Expt. Sta. Bull. 575. 34 pp. 192S . The principal ingredients of spray residue in the Hudson Valley are largely non-toxic. Cleaning methods have "been prin- ciaplly concerned with the removal of unsightly deposits, though it has been found that arsenic is also eliminated when other residues are removed. Hydrochloric acid is the only cleaning agent that has given satisfactory results. A bath of 1 minute in acid con- centrations of from 1:100 to 1:500 meets the requirements in most cases. It is sefe to treat fruit in 1:30 acid solution when arsenic removal is required but greater concentrations are not safe. Alkalies and oils are unsatisfactory. Hand wiping in- creases decay and cruses excessive wilting in storage. The ap- plication of late sprays to help remove residue has been without value. Even hydrochloric acid docs not function well when used as a spray for fruit hanging on the tree. Arsenic and fungicides containing lime are readily removed when fruit is floated in the solution :>f hydrochloric acid. The residue from sulphur sprays r.nd oil sprays is more difficult to remove. Weaker acid can be used if fruit is washed at picking ti:;e. Acid action is impeded by low temperature, wax, oil, and dirt. No method or material has been found for increasing the action cf hydrochloric acid on residue. SHEARER, J. W. (377) POISONOUS RESIDUES OP ARSENICAL SPRAYS. Pa. State Parmer 27 (2): 3. 1933. This is a short article, outlining a little of the his- tory of the residue problem and briefly touching on two methods of cleaning, dry cleaning and washing with hydrochloric acid (l to 4 gals, per 100 gals, of water), of which the latter is the most satisfactory. The discussion is based on information obtained from U. S. Dept. Agr. Farmers' Bull. 1687 (reference No. 2S7) and from W. R. M. Wharton and R. H. Sudds. SIMPSON, R. A. (378) GROWERS' PROBLEMS IN REMOVING SPRAY RESIDUE. Md. Agr. Soc. Rpt. 18: 132-134. 1933. Md. Sfte Hort. Soc. Proc. 36: 38-40. 1934. Fruit is treated in a pre-dip tank for 2-l/2 minutes with a solution of 6 pounds of Vatsol to 100 gallons of water, then passed through the acid bath and rinsed. Kadow of Ill- inois states that the accumulation of acid in the rinse can be easily neutralized by the addition of 1-1 1 2 pounds of lime per 100 gallons of rinse. Dr. Ruth is quoted as saying thot an acid bath of 110° F. would remove five times as much lead and arsenic as the same bath at 65°. LIBRARY STATE PLANT BOARD - 122 - SMITH, Z., RYALL, a. L., GROSS, C. R. , CaRTER, R. H., (379) MURRAY, C. W. , and FAHEY, J. E. THE REMOVAL OE LEAD, ARSENIC AND FLUORINE RESIDUE FROM APPLES. Wash. State Hort. Soc, Proc. 29th Ann. Meeting 1933: 86-96. Lead residue on fruit sprayed throughout the season with load arsenate alone or lead arsenate and spreader 'was usually removed to meet the lead tolerance where the better types of washing treatment were employed. Lead residues on fruit sprayed with lea.d arsenate and oil throughout the season or with oil in the second-brood sprays were generally so great that it "became practically impossible to clean such fruit to meet the tolerance even by the use of the most efficient washing treatments avail- able. Arsenical residues on fruit sprayed with lead arsenate with or 'without oil were satisfactorily removed by any method which satisfactorily removed the lead. Arsenical residues on fruit sprayed throughout the season with calcium or manganese arsenate plus mineral oil in several covers, were removed with- out difficulty by all of the acid washing treatments used, but not by sodium silicate. The lead and fluorine residues on fruit sprayed during the first brood with lead arsenate and during the second brood with two or three covers of cryolite plus either fish oil or mineral oil emulsion were in most cases satisfactorily removed where the better types of washing treatments were employed. The fluorine residues on fruit sprayed with cryolite plus' fish oil or barium fluo silicate plus fish oil for 6 covers were practically impossible to remove to meet the fluorine tolerance. Fluorine residues of cryolite and barium fluosilicate were removed with approximately equal difficulty. Fluorine residue removal a- mounted to only 85 to 90 percent even by the best washing pro- cesses available, so that it was impossible to satisfactorily clean fruit originally carrying 0.1 grain or more of fluorine per pound. The brush-flood and the double-process machines were more efficient than the pre-dip, the ordinary flood and the flotation types, especially for the removal of fluorine resi- dues. For lead and fluorine removal, the most efficient treat- ments were hydrochloric acid plus salt plus mineral oil in the brush-flood machine and sodium silicate followed by hydrochloric acid in the double-process machine. Efficient methods for lead but not for fluorine removal were the use of either sodium silicate or hydrochloric acid plus salt plus mineral oil in the flood machine, acid plus V~tsol wetting agent with or without salt in the flotation machine, and acid plus Vat sol followed by a,cid in the pre-dip machine. Fruit injury was noticed after some of the Jonathan washing tests, particularly after the a.cid treatment of fruit sprayed with cryolite, and was more pronounced where Vat sol wetting agent ha.d been used with the acid'. - 123 - smith, e. r. (380) PROBLEM OF ARSENIC CONTROL FOR FRUIT GROWERS. la. State Hort. Soc. Rpt. 1930: 102-107. The toxicity to man of lead and arsenic is discussed. The use of dilute hydrochloric acid for the removal of lead arsenate residue from fruit is recommended. Dry wiping is unsatisfactory. SNYDER, R. S., and MAG-NUSON, H. F. (381) THE REMOVAL OF ARSENICAL RESIDUE FROM APPLES. Idaho Agr. Expt. Sta. Bull. 187. 20 pp. 1931. The use of 1./3 percent hydrochloric acid as a '-ash solu- tion is sufficient to remove the arsenical residue to the -,'orld tolerance from apples not oil-sprayed at the "beginning of the season. Two-thirds or even 1 or l-l/3 "ercent acid may be used v;hen oil or wax accumulations cause more difficult removal. Con- centrations of acid above 2 percent are not advisable as injury to the fruit may result. The use of oil sprays seriously com- plicates residue removal. Removal also becomes very difficult when apples are placed in common storage or allowed to stand for some time before washing. Sodium chlorida additions to the a,cid wash solutions are erratic in their behavior, sometimes aiding in arsenic removal and at other times being of no value. Kero- sene emulsion is very useful in dissolving wax and oil accumula- tions when used with hot hydrochloric acid solutions. Where ar- senic removal '."/as difficult, heating the solution to 95° to 105° F. has brought about much more efficient removal than increasing the strength of the acid solution. STEINER, L. F. , SAZAMA, R. F. , and FAHEY, J. E. (382) INSECTICIDE TESTS TO CONTROL THE CODLING MOTH AT THE VINCENNES, INDIANA, LABORATORY DURING 1934. Ind. Hort. Soc. Trans. 1934: 66-71. 1935. Apples containing 0.097 grain of lead per pound of fruit were v/ashed with a pre-dip containing 1.7 percent (by weight) of hydrochloric acid plus 5 pounds of wetting agent per 100 gallons at 63° F, for 30 seconds, followed by the use of a jet-type wa,sher with ridged bar conveyor containing 1.08 percent acid for 45 seconds at the same temperature. This treatment did not reduce the lead to the federal tolerance of 0.019 gra,in per pound. STREETER, L. H. (383) STUDIES ON SPRAY RESIDUE. N. Y. State Hort. Soc. Froc. 76: 51-54. 1931. The process of picking, grading and packing removes from apples from one-^fourth to one- third of the quantity of lead arsenate - 124 - spray residue present at picking time. Hydrochloric acid is the "best solvent known for. residue removal. Apples carrying a residue of two or three times the tolerance were cleaned almost arsenic-free by this method. Dry cleaners are capable of removing light arsenical residues and insoluble residues such as sulphur de- posits. STREETIR, L. R. , CHAPMAN, P. J., HARMAN, S. W. , and PEARCE, 5. W. (384) SPRAY AND OTHER DEPOSITS ON ERUIT. N. Y. State Agr. Expt. Sta. Bull. 611. 19 pp. 1932. Approximately 40 percent of the residue found on apples is ' in the stem and calyx ends of the fruit. Residues other than ar- senical spray deposits often encountered rre sulphur fungicides, leafhopper specking, aphis and pear psylla smutting, and road dust. Mechanical dry cleaners are suitable for the removal of light or moderate residues. The washing method is more dependable for heavy residues. Washing machines equipped with polishing units are sat- isfactory for the removal of all types of residue. For New York conditions, a washing solution of hydrochloric acid 1 to 3 percent by volume is generally found adequate for the removal of arsenical residues. The best time- to clean apples is directly after picking before heavy "ax formation takes place. 1 CHAPMAN, P. J., pnd PEARCE, G. W; (385) EXPERIMENTS IN SPRAY RESIDUE REMOVAL. Jour. Econ. Ent. 24:^240- 244. 1931. Washing in a jet spray machine with 0.3 percent hydro- chloric acid by weight or 1 percent by volume of 20° Baume acid was sufficient to remove the arsenical residue from New York apples, and 0.5 percent by volume appears to be- adequate for light residues. Wiping was necessary to remove sulphur, road dust, leaf hopper excrement, and other insoluble residues. . and HARMAN, S. W. (386) SPRAY RESIDUES. N. Y. State A g r. Expt. Sta. Bull. 579. 12 pp. 1929. Of 94 samples of New York apples analyzed, only 3 contained arsenic equivalent to the tolerance limit, 0.01 grain of arsenious oxide per pound. Samples of apples taken from standard packages contained only two-thirds as much arsenic as apples taken from the trees. Cleaning of apples by hand wiping is not as efficient as washing. Of several solvents tested, sodium hydroxide pnd hydro- chloric acid were the most effective. Use of sodium hydroxide was discontinued because of its deleterious effect on the fruit. Hydrochloric acid is more suitable as a solvent because it is easily rinsed from the fruit and is volatile. One percent acid by weight (3 percent by volume) is sufficiently strong for remov- - 125 - ing arsenical residues. In removing residues in mechanical washers, acid strengths of 1 to 3 percent "by volume are usually recommended. The most advantageous time to clean apples is at the time of picking "before heavy wax formation occurs. STRICKLAND, A. G-. (387) B1M0YAL OF ARSENICAL SPRAY RESIDUE FROM APPLES. Victoria Dept. Agr. Jour. 29: 586-589. 1931. Experiments on the removal of arsenical residue from apples gave the following results in grains As^O^ per pound of fruit: (l) Untreated, 0.057; (2) washed with water and hand-wiped, 0.015; (3) Washed with l/3 percent hydrochloric acid for three minutes, 0.0024; (4) washed with 1 percent hydrochloric acid for two minutes, 0.0024. (388) REMOVAL OP ARSENICAL SPRAY RESIDUE PROM APPLES. Fruit World Australasia 33 (2): 77-78. 1932. The most successful wash for the removal of arsenical residue is hydrochloric acid at a strength of 1/2 to 1 percent. Experiments with four cases of apples heavily coated with arsenical residue gave the following results in grains As^O per pound of fruit: (l) Untreated, 0.057; (2) washed with water and hand-wiped, 0.015; (3) washed with 1/2 percent hydrochloric acid for three minutes, 0.0024; (4) 'ashed with 1 percent hydrochloric acid for two minutes, 0.0024. The fruit should "be well rinsed with fresh water. If the supply of water for rinsing is limited, the fruit should be dipped in a third hath containing 2 pounds of slaked lime to 80 gallons of water. No further rinsing should follow the lime water. Fruit should he i ,vashed immediately after picking, before wax develops. (589) SPRAY RESIDUES ON FRUIT. pTHODS OF REMOVAL. Victoria Dept. Agr. Jour. 31: 18-21. 1933. Washing of pears and apple? with hydrochloric acid, 1 to 3 gallons per ICO gallons of water, followed "by rinsing with fresh xvater, is recommended for the removal of arsenical spray residue. TAYLOR, W. A. (390) REPORT OF THE CHIEF OF TEE EUREAU OF PLANT INDUSTRY. 38 pp. 1928. It was found that wiping fruit either by hand or by machine was not sufficient to reduce arsenic spray residue to the required - 126 - tolerance. It became necessary to resort to washing the fruit with dilute solutions of either hydrochloric acid or alkalies, and fair- ly effective methods were developed "by tiie end of the past season. (391) REPORT CF THE CHIEF OF THE BUREAU. OP PLANT INDUSTRY. 39 pp. 1929. The addition of lime to the lead arsenate spray is a prac- tical preventive for arsenic injury in the washing process. Where • abundant fresh water is not available for rinsing, the use of a lime-water rinse effectively and economically prevents injury from soluble arsenic. (392) REPORT OE THE CHIEF OF THE BUREAU OF PLANT INDUSTRY. 33 pp. 1931. In the Northwest the pro'Glem of spray residue removal has become complicated through the use of various oils in the sprays. As a result, the use of heated washing solutions has been adopted to increase the efficiency of the hydrochloric acid. Salt and kerosene emulsion have also been found to facilitate the cleaning of fruit containing heavy deposits of oily residues. Washing peaches with hydrochloric acid was found to discolor the fruit. Cold alkaline washes produced no detrimental ef.ect when followed by thorough rinsing but such washes heated to 100° F. were in- jurious. TESCHE, W. C. (393) SPRAY RESIDUE WASHING- NOW A NECESSITY. Pacific Rural Press 117: 631-644. 1929. Because of the gradual tightening of the restrictions on arsenical residue, practically all pears and apples will soon have to be washed. Hydrochloric acid, 1 to 5 gallons of 32.1 percent to 100 gallons of water, is recommended as a solvent. THOMPSON, F. (394) SPRAY RESIDUE RESTRICTIONS REQUIRE EFFICIENT CLEANING. Calif. Cult. 71 (20): 496-497. 1928. Washing fruit with dilute hydrochloric acid is recommended. (395) SPRAY RESIDUE IN 1929.' Blue Anchro 5(ll): 16, 31. 1928. For the removal of spray residue, dry wiping machines are satisfactory for smooth-surfaced fruit not too heavily sprayed. However, washing fruit with l/2 to 1 percent - 127 - hydrochloric acid is the commonest method, although alkaline solvents such as caustic soda and carbonate of soda have "been used to some extent. VAN FILE, L. G. (3S6) SPRAY RESIDUE REMOVAL. Ark. Hort. Soc. P r oc. 50: 49-53. 1930. Washing apples with hydrochloric acid in a power washing machine removes excess spray residue, improves the appearance of the fruit, and does not affect the keeping qualities if prop- erly done. To avoid "bacterial decay in apples, the washing and rinse solutions should be changed quite often and the machine disinfected with formaldehyde solution from time to time. WAKELAND, C, and HAEGELE, H. W. (397) CODLING MOTH CONTROL IN IDAHO. Idaho Agr. Expt. Sta. Bull. 200. 26 pp. 1934. Suggestions for facilitating the removal of lead and ar- senic residues are given as follows: Do not use oil with a viscosity above 65 to 75. Do not make more than two oil applications during the season. Do not apply oil with, or over, lead arsenate for second-brood sprays. Pick the apples as soon as they are ready and wash immediately or place in cold storage until they can be washed. Use hydro- chloric acid at a strength of 1 to 1.6 percent or sodium silicate at a concentration of 60 to 90 pounds per 100 gallons for the wash solution. Eruit sprayed with fish oil can be cleaned more easily with sodium silicate. When fruit is difficult to clean, the wash- ing efficiency is increased by adding soap to sodium silicate solution or Vatsol to the acid solution. Sodium silicate fol- lowed by hydrochloric acid is required to clean the more difficult lots of fruit. Heat wash solutions to a temperature of 95° to 105° E. for early maturing fruit. Eor late fruit the tempera- ture may be increased another ten degrees. Washing machines should be made to hold the foam produced by the silicate-soap or the acid- Vat sol wash as the foam is important in increasing v/ashing efficiency. Rinsing should be done thoroughly and carefully. WASER, E. (398) tTBER DEN ZUllsSIGEN GEHALT VON LEBENSMITTEL AIT ARSEN. Mitteilung Gebifcte Lebensmtl. und Hyg. 20: 147-152. 1929. The arsenic load on sprayed fruit can be reduced by the - 128 - following means: (a) To small traces if spraying is carried out only short- ly after ."blossoming and not up until maturity of the fruit. (Done in Switzerland, in America apparently not). (b) To a greater or less degree accidentally "by rainfall. (c) By after treatment of the sprayed fruit "by 5 minutes' immersion in 0.3 to 0.5 percent hydrochloric acid and subsequent thorough washing in water. (Partially carried out in America.) (d) At least partly by peeling fresh apples and pears; with unpeelable fruits, dried fruits and fruit preserves this is natural- ly not possible. The author feels that the limit of 0.6 mg. of arsenic (trioxide) per pound of food established in England is too high. WEBER, A. L., and McLEAN, H.C. (399) THE REMOVAL OF LEAD AND ARSENIC SPRAY RESIDUES EROM APPLES. Jour. Econ. Ent. 26: 727-730. 1933. The new lead tolerance of 0.014 grain per pound can "be met under the following conditions: (l) With hydrochloric acid alone where no late oil sprays have "been used or no heavy wax coat is present; (2) with Vatsol or Alkanol B in conjunction with hydro- chloric acid where late oil sprays were used, "but the fruit has not "become waxy; (3) with Vatsol and hydrochloric acid where the fruit is heavily coated with wax and may or may not contain oil sprays. Alkaline washes did not remove lead satisfactorily. The use of wetting agents with acid gives the washed fruit a clean and attractive appearance while alkaline washes leave it with a dull, cloudy finish. WIEGAND, E. H. (400) UTILIZATION AND DISPOSAL OF CANNERY WASTE. Canning Age 15: 81-82, 108. 1934. In the dried form, apple and pear waste is usable as stock food and for the manufacture of pectin. However, the spray residue on the fruit is in excess of the permitted tolerance, which bars it from interstate shipment. This is caused by the concentration through peeling the fruit and drying the peels and cores. Of the methods of removal of residue from the fresh fruit, the double wash method, using 75 pounds of sodium silicate to 100 gallons at 120° F. with enough soap to just foam for the first wash followed by fresh spray, dipping in l-l/2 percent hydrochloric acid at 105° F. and. rinsing, offers the "best possibilities. Even this is not suf- ficiently effective to reduce the quantity to meet the concen- tration caused "by drying. - 129 - Because of the danger from insect infestation in brambles, some growers are using arsenical sprays. The very nature of these fruits makes it impracticable to dip to remove the spray. Unless care is taken, c&rmers will be packing fruit containing arsenic above the tolerance. WILLIAMS, C. G. (401) A PROGRESS REPORT OP THE DIRECTOR POR THE YEAR ENDED JUKE 30, 1930. Ohio Agr. Expt. Sta. Ann. Rpt. 49. 270 pp. 1931. Arsenical spray residue can be removed most satisfactorily by the use of one percent hydrochloric acid in which the fruit is floated for three minutes. One percent by volume of hydrochloric acid for two minutes was the minimum satisfactory treatment. Un- washed fruit contained 0.026 grain of arsenic per pound and washed fruit contained 0.006 grain. About half of the arsenic was in the calyx and cavity of the apple. 'When fruit was thoroughly rinsed in fresh water, the acid caused no burning. When it was not rinsed, very weak solutions of hydrochloric acid would cause burning. WOODWARD, C. R., and WALLER, I. N. (402) NSW JERSEY'S AGRICULTURAL EXPERIMENT STATION 1880-1930. €45 pp., illus. New Brunswick. 1932. In 1925 the presence of appreciable qurntitics of spray residue on apples caused faar cf poisoning, materially affecting the market demand. With a.n appropriation from the State emer- gency fund in 1927, p practical means of cleaning the fruit wag worked out by Cathcart and McLean. The investigations have been continued subsequently a.t the Experiment Station. McLean has shown that spray residues can be removed successfully v.'ith washes of caustic soda, and of hydrochloric a.cid. (p. 145) B . Apparatus ANONYMOUS (403) SPRAY RESIDUES. Tenn. State Hort. See. Proc. 24: 45. 1929. An outgrowth of fruit washing in the Pacific Northwest ha.s been the discovery of a calyx injury of apples due to soluble arsenic being forced into the calyx tube by certain types of washing machines. (404) HOME-MADE AND COMMERCIAL WASHERS. Hoooier Hort. 16: 135-137. 1934, Factors to be considered in selecting a fruit-washing machine are briefly discussed. The information is based in - 130 - part on U. S. Sept, Agr. Farmer l s Bull. 1687. [See reference No. 217.] ABILDGAARD, W. (405) THE FUTURE OF FRUIT WASHING IN THE EAST. Amer. Fsuit Grower 51 (3): 16-17, illus. 1931. Commercial types of washers and driers and their installation and operation are briefly discussed. BELL, J. W. , and BELL, T. J. (406) VEGETABLE WASHING APPARATUS. U. S. patent 1,617,096. Issued Feb. 8, 1927; applied for June 27, 1925. Vegetables such as celery, asparagus, carrots, spinach, etc., arc carried on a conveyer between tangentially directed sprays of water which penetrate between the leaves and stalks and the roughly wash away any dirt, insects*, or spray residues such -is arsenic. BREGGER, J. T. (407) FRUIT WASHING BECOMING A UNIVERSAL PRACTICE. Better Fruit 25 (11): 5-7, illus. 1931, The evolution of fruit cleaning is outlined. Four of the standard commercial washors used in the Pacific Northwest and other sections are described and pictured. CLARKE, J. 0. (408) PRESENT STATUS OF THE SPRAY RESIDUE PROBLEM IN MICHIGAN. Mich. State Hort. Soc. Ann. Rpt. 61: 66-70. 1932. The average reduction of arsenical residue on apples washed in all types of acid washing machines was 80 percent. CRUMMEY, J. D., AUSTIN, W. J., and LEWIS, F. H. (409) CONVEYOR. U. S. Patent 1,676,481. Issued July 10, 1928; applied for Apr. 30, 1928. Assigned to Bean Spray Pump Co. An endless conveyor for use in apparatus to remove spray residues on fruit comprises spaced parallel side chains composed of articulated links; spaced, parallel cross members connecting opposing corresponding links; and a rubber cushion sheath completely enveloping each cross member, the ends of said sheath being stretched to cover and bind upon the link and cross member connection. - 131 - CUTLER, v. W. (410) PR0GRESS0R FOR A TRANSVERSE BRUSH FRUIT TREATING MACHINE. U. S. Patent 1,997,044. Issued Apr. 9, 1935; applied for Jan. 31, .1933. Assigned to Pood Machinery Corporation. This machine removes spray residue from apples. FHSStiAH, J. G. (411) COMMERCIAL WASHERS. Ill, State Hort. Soc. Trans. 64: 183-185. 1930. The capacities and prices of several models of apple washing machines are given. GARVER, H. L., DMA, H. J., and OVERLSY, P. L. (412) THE STATE COLLEGE OF WASHINGTON EXPERIMENTAL FRUIT WASHER. Hash. Agr. Expt. Sta. Bull. 285. 28 pp., illus. 1933. Plans and directions arc given for the construction of a fruit washing machine. GOODALS, E. J. . (413) APPARATUS FACILITATING GERMICIDAL TREATMENT AND WASHING OF FRUITS. U. S. patent 1,973,062. Issued Sept. 11, 1934: applied for Nov. 17, 1931. Assigned to George H. Joceylyn. A machine for removing spray residue from ap;oles is described. GOODWIN, G. S. (414) FRUIT CLEANING MACHINE. U. S. patent 1,923,722. Issued Aug. 22, 1933; applied for Apr. 1, 1929. This invention pertains to a fruit cleaning machine of the surge tank, float and duct return type of liquid washer and rinsor and is designed to wash and rinse apples, pears, peaches, orongos, lemons, or other similar tyncs and forms of fruit where ouch cleaning may be necessary on account of the removal of spray, dust, or other foreign matter from the surface of such fruit; or for the purpose of giving such fruit a liquid sanitary, disinfectant or prophylactic treatment. GUI GUARD, A. (415) MACHINE FOR STERILIZING, WASHING, AND DRYING FRUIT. U. S. patent 1,748,019. Issued Feb. 18, 1930; applied for May 17, 1927. This apparatus comprises tanks designed to hold solutions for the treatment of apples and pears or other farm products, - 133 - conveyers "being provided to carry the fruit through the tanks, and a drying machine for the fruit. The solutions used arc: dilute acid solutions to remove spray residues, e. g. lead arsenate, adhering to the fruit; ■ sterilizing solutions, e. g, aqueous formaldehyde solution, to destroy bacteria or other microorganism on the fruit; and water to remove any of these solutions remaining on the fruit. — BOSSE, A., and GUI GUARD, J. (416) APPARATUS FOR TREATMENT OF DECIDUOUS FRUIT. U. S. patent 1,707, 610. Issued Apr. 2, 1929; applied for Mar. 2, 1927. Fruit carried on an endless conveyor is subjected to sprays of acid solution, e, g, 1 percent hydro chloric acid, for about 20 seconds to neutralize the residue of lead arsenate or other poisonous spray compound or insecticides; then to sprays of water, and finally to the drying action of revolving brus ! ■> and a current of warn air. EAHTLIAtf, a. (417) THE 0H3GOH APP LE -U A SHE R. Oreg. Agr. 3xpt. Sta. Circ. 92. 7 pp., illus. 1929. Plant', and directions are given for the construction of an apple—washing machine . IITGSRSOK, H. G. (418) FRUIT CIEAEIHG EQUIPiiEET-- PAST, PRESENT AITD FUTURE. Neb. State Bd. Agr. Ann. Rpt. 1931: 486-490. 1931. The history of the development of fruit cleaning equipment is traced. Present equipment and prospects for the future arc briefly discussed. (419) FEUER DEVELOP! "ErTTS IN FRUIT WASHERS. Del. State Bd. Agr. Quar. Bull, 21 (5): 99-105. (1932?) The history of fruit washer development is traced and the requirements of the future fruit washer are outlined, including careful handling, ample capacity, drying and polishing, compact construction and permanency. A newly developed washer equipped with under- brushes in washing, rinsing and drying sections is described which is very satisfactory. - 133 - INGRAHAM, H. A. . . (420) FRUIT CLEARER. U. S. patent 1,757,308. Issued May 6, 1930; applied for Jan. 19, 1927. A machine for removing from fruit dust or like deposits re- sulting from spraying with Bordeaux mixture, arsenate of lead, or other insect or fungus-destroying liquids is described. (421) FRUIT-CLEANING MACHINE. ' U. S, patent 1,780,924. Issued Nov. 11, 1930; applied for Mar, 2, 1928. This investion relates to machines for removing from fruit, duet or like deposits resulting from spraying with Bordeaux mixture, arsenate of lead, and other insect or fungus-destroying liquids. JOHNSON, 3. G. (422) THE HOME-MADE APPLE WASHER. 111. State Hojrt. Soc. Trans. 64: 178-182, illus, 1930. The construction of a home-made apple washer is discussed. KOHLER, A. R. (423) EXPERIENCE WITH A HOME-MADS FRUIT WASHER. N. J. State Hort. Soc. Proc. 1931: 77-82. 1932. A home-made fruit washer "built from the plans of H. C. McLean [See reference no. 426] satisfactorily removed arsenical residue. Some slight changes in construction are suggested. L IRIAN, J. G. (424) REPORT OF THE DIRECTOR. N. J. Agr. Expt. Sta. Ann. Rpt. 1930-1931, pp. 1-85. 1931. For the grower who has but a small lot of apples or pears, averaging less than 3,000 "bushels, hand dipping is the most practical and economical method of removing spray residues. For the grower producing 3,000 to 15,000 "bushels of apples, the home-made paddle washer has proved the most efficient. Commercial chemical fruit washers are recommended where larger quantities of fruit are cleaned annually. The -unavoidable bruising sustained in the procecs of cleaning is considerably reduced with the commercial washer as compared with the paddle washer and hand dipping. - 134 - McLEAN, H. C. (425) A PROFITABLE SOLUTION OF THE SPRAY RESIDUE PROBLEM. N. .J. State H rt. Soc. Proc, 1930: 252-258. 1931. The use of the dipping tank, home-made paddle washer and Bean chemical fruit washer for washing with hydrochloric acid, and precautions to be used in washing are discussed. (426) HOMEMADE FRUIT WASHER. Del. Agr. Bd. Quar. Bull. 23 (5): 87-90. . 1934. Plans and directions arc given for the construction of a padc washer. Instructions are also given for determining the strength of the hydrochloric acid solution in the washer. MAGNUSON, H. P. . (427) FRUIT WASHING ADVISABLE. Oreg. Farmer. 49 (7): 133. .1929. The reduction in the domestic tolerance for arsenic on apples for this season (1929) is going to make it necessary to wash the fru in many cases where the growers have "been able to meet domestic tolerance by wiping in former years. Washing machines should be avoided that submerge the fruit deeply. A diffused spray or flotatior or flood wash type or combinations of these are effective. HOE, A. D. (428) METHOD OF AND APPARATUS FOR CLEANING FRUIT. U.S. patent 1,983,478. ' Issued Dec. 4, 1934; orig. application Mar. 24, 1928; divided and filed July. 23, 1929. Assigned to Food Machinery Corp* A machine for removing lead arsenate spray residue from apples is described. MORRIS, D. C, and C0CKRILL, L. 0. . (429) APPARATUS FOR PREPARING FRESH FRUIT FOR MARKET. U. S. patent 1,932, fl Issued Oct. 31, 1933; applied for June 25, 1928. Assigned to Brogdex Company. A principal object of the present invention is to provide apparatus for removing foreign matter from fruit in general and more particularly for removing poisonous spray residues, e. g, lead arsenate, from apple-s, pears and the like, REED, A. H. (430) PROBLEMS IN HEATING THE WASH WATER IN APPLE WASHING MACHINES. Ill, State Hort. Soc. Trans. 67: 276-289. 1934. The advantages and disadvantages of various systems of heating discussed. - 135 - HBUEHIE, J. A. (431) FRUIT CLEANER. U. S. Patent 1,464,775.. Issued Aug. 14, 1923; applied for May 18, 1922, Assigned to National Fruit Cleaner Co. Means for effectively cleaning fruit that has received a late spraying after the fruit has formed, without removing the coating provldod by nature, which resembles paraffin, is described. RIDLEY, G. B. (432) FRUIT WASHER. U. S. Patent 1,674,064. Issued June 19, 1928; applied for Apr. 11, 1927, Assigned to Bean Spray Pump Co, A drier for apples, pears or other fru.it which have "been washed to remove lead arsenate or other spray residues utilizes compressed air jets. ROARi:, R. C. (433) THE EHEHD HI PEST CONTROL INVENTIONS IK THE UNITED STATES. Jour. Econ. Ent. 25: 730-731. 1932. Only three patents for fruit-washing apparatus wore issued by the United States Patent Office during 1931. (434) PATENT LIST NO. 35. A LIST OF UNITED STATES PATENTS ISSUED FROM 1917 to 1933 INCLUSIVE RELATING TO DRIERS FOR WASHED FRUIT. U. S. Dcpt. Agr. , Bur. Ent. and Plant Quar. , Insec- ticide Div, , Mirneo. Publ. 4 pp. 1934. Nineteen patents covering driers for wanned fruit arc listed. (435) PATENT LIST NO. 35. A LIST OF UNITED STATES PATENTS ISSUED FROM 1917 to 1933 INCLUSIVE RELATING TO APPARATUS FOR WASHING INSECTICIDE RESIDUES FROM FRUITS AND VEGETABLES. Part I. Tank washers. U. S. Dcpt. Agr., Bur. Ent. and Plant Quar., Insecticide Div., Mimeo. Publ. 6 pp. 1934. Thirty-two patents for tank-type washers for clean- ing fruits or vegetables are listed which might be used for the removal of spray residues. - 136 - (436) PATENT LIST HO. 37. A LIST OF UlTIOSD STATES PATENTS ISSUED FEDIi 1917 to 1933 INCLUSIVE RELATING TO APPARATUS. FOR WASHING INSECTICIDE RESIDUES FROA FRUITS AND VEGETABLES. Part II. Scrubbers and assorters. U. S. Dopt. Agr. , Bur. Ent. and Plant Quar. , Insecticide Div. , Mimco. Publ. 10 p. 1954. The sixty-seven devices described in this list include a number which might be adapted for use in the removal of spray residues. ( 437 ) PATENT LIST HO. 38. A LIST OF UNITED STATES PATENTS ISSUED FROM 1917 to 1933 INCLUSIVE RELATING TO APPARATUS FOR WASHING INSECTICIDE RESIDUES FROA FRUITS ML VEGETABLES. Part III. Conveying washers. U. S. Dept. Agr., 3ur. Ent. and Plant Quar., Insecticide Div., Himeo. Publ. 11 pp. 1934. The seventy patents in this list include apparatus for washing fruit on an endless conveyer. (438) PATENT LIST NO. 39. A LIST OF UNITED STATES PATENTS ISSUED FROLI 1917 to 1933 INCLUSIVE RELATING TO APPARATUS FOR WASH- IITG INSECTICIDE RESIDUES PROA FRUITS AND VEGETABLES, Part IV. Conveying brush washers. U. S. Dept. Agr., Bur. Ent. and Plant Quar., Insecticide Div., Aineo. Publ. 12 pp. 1934. Patents for devices for cleaning fruit by means of brush machines are listed. (439) PATENT LIST NO. 40. A LIST OF UNITED STATES PATENTS ISSUED FROM 1917 to 1933 INCLUSIVE RELATING TO APPARATUS FOR WASH- ING INSECTICIDE RESIDUES FROA FRUITS AND VEGETABLES. Part V. Miscellaneous devices. U. S. Dept. Agr. , Bur. Ent. and Plant Quar. Insecticide Div., Mimeo. Publ. 8 p. 1934. Various types of machines . adapted for cleaning fruits of spray residues are listed. (440) A REVIEW OF NON-CHEAICAL UNITED STATES PATENTS ISSUED FROA 1917 to 1933, INCLUSIVE, RELATING TO INSECT CONTROL. U. S. Dept. Agr., Bur. Ent. and Plant Quar., Div. Insecticide Invest., ilultigraph Publ. 4 pp. 'June 1935. Forty-seven patent lists have beun issued by the Division of - 137 - Insecticide Investigations listing all U» S. patents issued from 1917 to 1933, inclusive, relating to insect control. Six of these, numbers 35-40, relate to apparatus for washing insecticide residues from fruits and vegetables. ROGERS, J. V. (441) METHOD AND APPARATUS FOR TR.ATING FRUITS AND VEGETABLES. U.S. patent 1,983,403. Issued Dec. 4, 1934; applied for Feb. 23, 1928, renewed Mar. 12, 1931. Assigned to Food Machinery Corp. An apparatus for washing lead arsenate spray residue from apples is described. SCHERER, P. A. (442) HANDLING FRUIT. U. S. Patent 1,657,132. Issued Apr. 24, 1928; applied for Apr. 11, 1927. Fruit is placed in a liquid stream which carries it along to a conveyer which may carry it into another liquid. The liquids may be acid for removing spray residues, disinfectants, such as formaldehyde (1 gal. to 100 gals, water) to prevent blue mold, brown rot, perennial canker, anthracnose or other fungus, water or any other liquid desired. STSBLER, F. (443) FRUIT SCRUBBER. U. S. Patent 1,684,896. Issued Sept. 18, 1928; applied for Jan. 31, 1927. A brush roll machine for scrubbing fruit, e. g. apples on which there is lead arsenate residue, is described. (444) WASHING FRUIT SUCH AS PEARS FOR REMOVING SPRAY RESIDUES, ETC. U. S. Patent 1,945,922. Feb. 5, 1934 (to Food Machinery Corp.). In washing lead arsenate from fruit with a solution such as hydrochloric acid of lower specific gravity than that of the fruit, the fruit is supported while partially submerged in the solution and the solution is sprayed over it. Apparatus is described. THOMPSON, A. R. (445) PUiiPLESS WASHER. U. S. patent 1,934,833. Issued Nov. 14, 1933; applied for Jan. 23, 1932. Assigned to Food Machinery Corp. A washer suitable for removing residual deposits of insecticide or fungicide from fruit comprises a liquid-containing tank in which is a plurality of rotatablc brushes arranged in parallel relation. - 138 - V7IIITE, E. A. (446) FKJIT-CISMIKG APPARATUS, U. S. patent 1,676,306. Issued July 10,192? applied for Oct. 15, 1926.- A machine for "brushing fruit to remove dirt, dust, poison residue and other foreign matter is described. (447) FRUIT TREATING MECHANISM. U. S. patent 1,931,565. Issued Oct. 24, 1933; applied for May 15, 1929. A purpose of the invention is to remove poison spray sediment from fruit, e. g. apples, although it is also adapted for use in re- moving soil from potatoes, topped "beets or the like. WUEST, G. A. (448) FRUIT WASHING AND DRYING MACHINE. U. S. patent 1,951,046. Issued 13, 1934; applied for Sept. 22, 1927. This invention has for its object the cleaning of fruit such apples and pears, which while growing are sprayed with a poisonous solution. IV, RELATION OF THE SPRAY PROGRAM TO RESIDUE ANONYMOUS (449) MOTH CONTROL TO MEET RESIDUE EDICT. Better Fruit 21 (10): 11, 12. 1927. Gives recommendations of the Yakima Valley growers' spray residue committee and of the Washington State and Federal authorities as to cultural and spray practices to reduce the amount of lead arsenate spray residue on the harvested apples. (450) THE SPRAY RESIDUE PROBLEM. Canadian Hort. 51: 31. 1928. In an effort to avoid the problem of spray residues, various substitute measures for the control of the codling moth have been suggested, e.g., traps using fermented cider bait; the rear- ing of ^ray bats, which eat the moths; and the cultivation of a small wasp, Trichogamma minutum , parasitic on the moths. (451) LIME AIDS SPRAY RESIDUE WASHING. Pacific Rural Press 119: 438. 1930. The Oregon Experiment Station recommends the addition of - 139 - 1 or 2 po\i.nds of hydrated lime to each 100 gallons of leal arsenate spray to facilitate the remsval of spray residue from apples and pears. . (-',52) SPRAY RESIDUE. Market Growers Jour. 52: 130. 1933. Lead, arsenic, fluorine and conper are the principal poisonous elements in insecticidal spray residues. Means sug- gested for avoiding excessive residues are: avoiding over- heavy spraying or dusting; controlling insects and diseases when plants are young, making late treatment less necessary; use of non-poisonous insecticides, e.g., tobacco, pyre thrum and derris; trimming outer leaves from such vegetables as cabbage and cauli- flower; washing fruit with water or weak acid solutions. ACKSPMAN, A. J. (453) ARSENICAL SPFAY RESIDUE OH HARVESTED FRUIT IN RELATION TO THE CONTROL OF CODLING NOT:. ON PEARS. Calif. Dept. Agr. Mo. Bull. 11: 12-26. 1922. Growers ^f pears in the Sacramento Valley of California have "been troubled with arsenical spray residues on pears shipped east during the past few years. Efforts should he directed toward thorough control of the codling moth in the early sprays to elimi- nate the possibility of infestation late in the season and conse- quent very late applications. The last cover spray should he finished about three weeks "before the first picking. Coarse drenching sprays that leave the fruit blotched and heavily coated with spray material should be avoided. ALEE1T, C. H., and YEOMANS, M. S. (454) CODLING MOTH CONTROL IE GEORGIA APPLE ORCHARDS, Jour. Scon. Ent. 21: 319-324. 1928. The arsenical content of fruit sprayed with arsenate of lead in liquid form according to the Georgia spray schedule was within the international tolerance limit of 0.01 grain per pound of fruit. BOURNE, A. I. (455) SPRAY RESIDUE PROBLEM AND ITS RELATION TO ORCHARD PRACTICES. Mass. Agr. Expt. Sta. Bull. 247 (Bienn. Rpt. for fiscal years ending Nov. 30, 1927 and 1926): 317-318. " 1329. In dry seasons or with moderate rainfall, present spray practices for later spraying will need modifications. Dust applications show less residue on fruit at harvest than sprays. - 140 - TIE SPEAY HSSIUU3 PROBLEM. Mass. Agr. Expt. Sta. Bull. 271 (Ann. F.pt. year ending Nov. .30, 1930): 257-258. 1931. (455) In oil cases where sprays rtrc applied after July 15, sprc :ding or sticking agents should be omitted and lighter strength of lead arsenate used. Dusts, if properly applied to liclntosh or Baldwin, could be used as late as August 15 without encountering any difficulty. (457) IKE SPEAY. HSSIDGS P30BLBM. Mass. Agr. Expt. Sta, Bull. 280 (Ann. Ept, for the year ending Kov. 30. 1931) I 216. 1932. Studies emphasized the advantage of dusts over sprays for late summer use. Dusts nay be safely used within 2 to 3 weeks of harvesting apples. (458) THE SI- RAY PES I DUE PB0B1EM. Mass. Agr. E x oU Sta. Bull. 293 (Arm. Kpt. year ending Nov. 30, 1932): 31. 1933. Growers who sprayed late in July or early in August encountered the problem of residue or Mcintosh in excess of the tolerance or dangerously near it. Busting in late summer again proved one of the most satisfactory solutions of the problem under Mao r ,achuse;t bs conditions. Encouraging preliminary tests with a non-arsenical stomach -poison indicate a possible way out of the difficulty without forcing growers to wash their fruit. (459) TEE SPRAY RESIDUE PROBLEM. Mass. Agr. Expt. Sta. 3ull. 305 (Ann. P.pTi u year ending Nov. 30, 1933): 31-32. 1934. To avoid danger of lead or arsenic residue without the necessity of washing fruit, it is recommended that lead arsenate in an amount exceeding 3 pounds to 100 gallons should not be applied within 8 weeks of harvests and that no arsenical spray be applied within 6 weeks of harvest. In the case of dusts, at least a 90 to 10 sulfur-lead arsenate dust may be safely employed as late as 4 wcoks before harvest. BUPJETTE, E C. (450) PEPPEP.liA.GGOT. IT. J. Agr. Sxpt. Sta. Ann. Rpt. 1928-1929, pp. 184-187. 19-30. "The use of arsenical s for the control of the fly seems - 141 - to "be very limited; Two sprays may "be out on, but the growth of the poppers is so rapid that a large amount of arsenical residue would he found on them when marketed. It was necessary to wash the peppers "before they were used when only two applications (of lead arsenate) were made." BURKHOLDER, C. L. (461) RESIDUE LOADS RESULTING FROM FIRST AND SECOND BROOD SPRAYS. Ind. Hort. Soc. Trans. 1934: 45-47. 1935. Grimes apples from trees which had received a cover spray and three first-brood sprays of lead arsenate with 2 quarts of summer oil per 100 gallons as a sticker and ovicide carried a lead load of 0.016 grain per povnd at harvest compared to 0.0047 grain per pound for fruit which did not receive the oil. "hile heavy and frequent cover sprays applied during the first-brood period in June do not result in heavy residue at harvest, one cover spray applied 3 to 4 weeks before picking may be alone responsible for a lead load at harvest of 0.08 to 0.10 grain. BUEKHOLDER, C. L. , and FORD, 0. W. (462) SPRAY DIG AND RESIDUE EXPERIMENT S CONDUCTED AT LAFAYETTE, 1932. Hoosier Hort. 15 (6): 84-88. 1233. Ind. Hort. Soc. Trans. 1932: 57-61. 1953. The use of two second brood sprays of barium fluosllicate and summer oil resulted in as great an arsenical load on apples as in plots which received either one or two lime-lead sprays for second-brood codling moth. Plots receiving 1/4 percent linseed oil in the first cover spray carried a heavier arsenical load at picking time than plots on which l/4 percent soy bean oil was used. The use of wet table sulphur, Bordeaux, or dry lime-sulphur as fungi- cide did not affect the arsenical load at harvest. Plots receiving one second-brood lime-arsenate application showed 28 percent less arsenical load than plots receiving two. Three first brood cover sprays of lead arsenate gave 9 percent less arsenical load than two first-brood and one second-brood spray., The use of a- sticker for lead arsenate in applications following the first cover spray for first brood will noticeably increase the arsenical residue. Uhen first-brood arsenical sprays are followed by a second-brood spray program of 1 or 2 percent summer oil or oil-barium fluo sili- cate, normal weathering off of the arsenic is retarded and as heavy an arsenical load a.t harvest may result as when arsenicals are used for both first and second brood sprays. CAFFPEY, D. J. (463) IIETHODS OF CONTROLLING TRUCK-CROP INSECTS AiTD AVOIDING HARMFUL RESIDUES. Md. Agr. Soc. Rpt. 19: 272-278. 1955. The Bureau of Entomology and Plant Quarantine has carried out investigations on the control of truck-crop insects by methods - 142 - that will not leave harmful residues on the marketed product. The use of lead arsenate is not recommended for the control of insects attaching any vegetable crop mentioned in the discussion (cabbage, cauliflower, broccoli, kale, collards, beans, celery, squash, lettuce, spinach and tomatoes) "because of the double residue hazard incurred by its .''cad content and its arsenic content. The use of other arsonicals and cryolite is suggested in the control of insects on certain of these crops, with the qualification that such poisons should not be us^d after the appearance on the plant of fruit or foliage which will be sent to market or consumed, except in cases where it is known that washing or stripping will remove all spray residues. CAPPER, R. H. , and NSNCOISR, S. J. (464) ARSENICAL RESIDUES FOUND OH APPLES IK TEE PACIFIC NORTHWEST THROUGHOUT A SEASON OP TYPICAL SPRAY I1TG UITH LEAD ARSENATE. Jour, Econ. Ent. 26: 572-580. 1933. The authors conclude that the major part of the spray residues on harvested fruit is due to the late applications* By using substitutes for lead arsenate in only the last two applications • of the schedule under consideration, 50 percent of the final arsenical residue could be avoided. The figures representing grains of arsenical residue per pound tend to decrease throughout the season while the figures for mg, per cq. cm, of surface area 4 "rnd to remain constant or increase. This is due to the different rates of increase of weighs and surface area. (465) CODLING MOTH AND ITS CONTROL IN THE HOOD RIVER VALLEY. Better Fruit 28 (8): 7, 17. 1934. Generally speaking, the residue load on fruit at harvest time is greater where oil has been used in the spray schedule, particularly where the oil has been employed in late applications. Fruit of this character is cleaned with much more difficulty than where oil has not been applied or has been used in first brood control only. CLEVELAND, C. R. (466) COIZPAEJSON OF ARSENATE OF LEAD AID SUalER OIL FOR CONTROLLING SUrHiER BROODS OF CODLING NOTE. Ohio State Hort. Soc. Proc. 55th Ann. meeting, pp. 139-143. 1932. In cases of severe codling moth infestation, where facilities for residue removal arc available, summer oil at 3/4 or 1 percent with lead in 1 or 2 peak emergence first brood sprays, followed by 1 percent summer oil plus nicotine sulphate (1:1600) in second and third brood sprays, will improve control materially and permit residue removal without difficulty. Where facilities for residue - 143 - removal are not ava.ili.olc, lead only in first "brood sprays with stunner oil and nicotine in the later sprays will still give some improvement in control and will render residue removal unnecessary in practically all instances. COX, A. J. (467) CALIFORNIA SPF.AY RESIDUE SITUATION. Calif. Cult. 80: 259, 271. 1933. A general discussion. The use of non-lead arsenicals, pyre thrum and nicotine sulfate, on leafy and other vegetables is recommended. OUTRIGHT, 0. H. , and HOUSE R, J. S. (466) EXPERIMENTAL RESULTS IK COELIKG r£0TH C02TTR0L 7ITH LATE SUMIIER OIL APPLICATIONS, Jour. Leo:.. Ent. 26: 380-383. 1933. Ho harmful arsenical residues resulted when lead arsenate was used in the calyx and first cover sprays and oils were .sub- stituted for arsenicals in lat;: season sprays. DELASSUS (469) LES TRAITEMEKTS ARSENIC AUX LIS AEBEES FRUI TIERS. Rev. Agr. Afr. Nord. (n.s.) 8: 278-262. 1923. In Algeria, applications of arsenicals to apples should not he made later than ten days after "blossoming. DIEHL, H. G. (470) USE OE SPRINKLERS III ORCHARD IRRIGATION. Wash. State -ort. Assoc. Froc. 1930: 51-53. There is a distinct reduction in the average load of spray residue on fruit oaken from trees in overhead sprinkler plots. DIEHL, H. C, EZELL, B. Z. , and FY ALL, A. L. (471) RELATION OF OTHER FACTORS IF SPRAYING AND CLEANING PRACTICES TO EFFICIENCY OF REMOVAL. Uash. State Hort. Soc. Froc. 2^: 100-111. 1928. use of oils in combination with lead arsenate for spraying increases the difficulty of removing the lead arsenate residue. The addition of a spreader to the combination makes clean- ing easier. The amount of lead arsenate applied with oils of any kind is an important factor in residue removal. - 144 - DIIOCS , CO.. . (472) APPLE PFJJIT PLY OE BAILBOAD SOHLT. ¥.e. A fc r. Expt. Bta. Bvll, 369 ( Summary report of progress, 1933): £51-552, 1933. Apples sprayed ?j oh calcium arsenate retained, the last week oi September, a re sidue 1/5 tc 1/10 the amount of that present one month earlier, while the corresponding fraction for apples sprayed , their skins, juice, and f or agreed juice. Only the yeast settlement from the fermented juice contained a C to 1.5 mg of lead end f 54 to, l.?7 mg. of arsenic per 100 g, of dry substance e One litter of juice contained from traces to 0.6 mg. of arsenic, the wine up to 0.2 mg. of arsenic. FLINT, W. P. (668) INSECT CONTROL WORK OF THE NATURAL HISTORY. SURVEY FOR 1927, 111. State Hort. Soc. Trans. (1927) 61: 99-110. 1928. Analyses were made of a number of lots nf apples for which the exao'- spray schedules and the amounts ,of spray applied were known,, Most oi these samples did not show residues in excess of the export tolerance, FORBES, S. A. (669) SPRAYING APPLES FOR THE PLUM-CURCULIO. 111. Agr. Expt. Sta. Bull. 108: 263-285. 1906. Analysis of peelings from apples picked the day after they were sprayed for the second time (at a month's interval) with 12-l/2 - 197 ~ o«. of lead acetate and 5 oz* of sodium arsenate to 12-l/2 gals of water (4 times the usual strength) showed the presence of 35*6 p. p.m. . of arsenious acid, equivalent to 0.2562 grain of arsenic per pound of peelings. Apples from another tree sprayed as above, but with one-fourth the concentration, and which had received earlier arsenical sprays also, contained 32.9 p. p.m. (0.2303 grain arsenic per pound of peel- ings). A third tree was treated in the same manner as the last, us- ing the more concentrated lead arsenate spray. These apples were not analyzed until 2 months after the last spraying, and after being shipped, but they contained 40.1 p. p.m. or 0.2807 grain of arsenic per pound of peelings. Two grains of arsenic is a fatal dose and l/30 . to 1/10 grain is a medicinal dose. "While these facts are not at all alarming, they suggest discretion in the use of this insecticide and the subsequent handling and disposal of the apples." FRIGERIO, M. (670) THE COPPER CONTENT OF SUGAR-BEST LEAVES TREATED WITH COPPER COM- . POUNDS, AND CHANGES IN THEIR OXALIC ACID CONTENT Giorn. Chim. Ind. Applicata 11: 67-69.1929 (In Italian. Abstract in Chem. Abs. 23: 3769. 1929.) The copper retained by leaves of beets sprayed with copper salts as insecticide varies very much, depending among other things upon the amount of rain, etc., subsequent to the spraying. GARCIA, F. (671) FORTY-FIRST ANNUAL REPORT. N. Mex. Agr. Expt. Sta. Ann. Rpt. 41: 108 pp. 1930. The amount cf arsenical residue on apples from parts cf New Mexico where heavy arsenical spraying was not necessary and where much residue was washed off by rain ranged from 0.002 to 0.028 grain of arsenic trioxide per pound for 13 samples, only 2 being above 0.01 grain per pound. Samples from the horticul- tural farm of the experiment station where spraying was heavier and rainfall lighter ranged from 0.0154 to 0.077 after spraying and from 0.0231 to 0.0693 at harvest. In some cases the data show an increase after the clese of the spraying season, probably due to difficulty in selecting representative samples. (pp. 67-68) GARINO, E. (672) DETERMINAZIONE DELL'ARSENICO NEL VINO PROVENIENTE DA UVE SOGGETTE A TRATTAMENTO CUPR^« ARSENIC ALE. Ann. R. Accad. Agr. Torino 56: 78-82. 1913 The amounts of arsenic and copper found in grapes which had re- ceived copper-arsenical treatment are given. - 198 ~ GASMAN, H. ('673) I. SPRAYING FOR CODLING-MOTH. 'MI. THE USE CF ARSENITES ON TOBACCO. 'Ky. Agr. Expt. Sta. Bui. 53',. p. 117-143. 1894. . , Apples from a tree sprayed once with, london purple, (l lb. t* ■ 160 gals.) and 4 times with paris green (l lb. to 160 gals.), "between July 11 and Auguet 27, gave no reaction for arsenic, while a small, unweighable quantity of copper was found* Analyses of tobacco which had "been sprayed with paris green revealed the presence of arsenious oxide in quantities ranging from 0.07 to 1.11 grains per pound and cupric oxide from an unweighable amount up to 0.41 grain per pound. GUNTHER, A. . , (674): .' ERGEBNISSE DER AMTLICHEN WEINSTATISTIK. BERICHTSJAHR 1906*^1909. Teil L. Weinstatistische Untersuchungen. Einleitung. ArT3» liaiserl. Gesund- heitsamte 35: 1-26. 1910. Data are given, in tabular form, relative to the arsenic and lead content of fruit from trees and "bushes sprayed with arsenic and lead (so- dium arsenite and lead acetate) and to the arsenic and copper content cf fruit from trees and "bushes dusted with arsenic- sulphur powder (lime, sulphur and paris green). HARTZELL, A., and WILC0X0N, F. (675) THE ARSENIC CONTENT OF SPRAYED APPLES. Jour. Econ. Ent . 20: 204-212. 1927. Individual analyses of 47 apples from trees sprayed according to the standard schedule comprising 5 applications of lead arsenate (4 Ids, to 150 gals.) at Yonkers, New York, during the season of 1926, gave an average of 0.173 mg. of arsenic trioxide per kg. of fruit and a maximum of 0.704 mg. per kg. The quantity allowed "by the Royal Com** mission on Arsenical Poisoning in 1903, was 1.429 mg, per kg. of food- stuffs. Analyses of cider (50 cc.) and jelly (30 g.) made from apples from this experiment showed arsenic in such minute quantities that the determinations did' not differ from the "blanks of the reagents "by any measurable amounts. and WILCOXON, F. (676) ANALYSES OF SPRAYED ATPLES FOR LEAD AND ARSENIC. Jour. Econ. Ent. 21: 125-150. 1928. Apples grown at Yonkers, New York, that had received the stan- dard spray schedule comprising 5 applications cf lead arsenate (4 l"bs. to 150 gals.), during the season of 1927, showed on analysis an average of 0.912 mg. of metallic lead per kg. of fruit and a maxiumu of 1.80 mg. - 19S - per kr, Tne arsenic trioxide found in the samples averaged 0.099 mg« per kg, with a aaxliaum of 0,193 mg„ per kg,, considerably below the limit adopted by the Royal Commission on Arsenical Poisoning in 1903 (1.439 nig. per k*«). EEDRICK, "J. P. (677) FIFTY- SECOND ANNUAL REPORT 01 THE NSW YCHK. STATE AGRICULTURAL EXPERI- MENT STATION. N, 1. State Agr. Expt. S + a. Ana, Rpt. 52. 113 pp. 1933, Following sn embargo on Long Island cauliflower in October, 1932, because of excessive arsenical r^sidx^e en fie marketable pro- duct , it was fcand bj analyses that the greatest -mount of arsenical residue was retained at the butt cad of the har^cs-ed product and that by the elimination of those parts tar re was lit tie danger of exceeding the tolerance. Consequently, it was decided to allow interstate shiraert to Id rosumed m ovided heads were "close trimmcd<, H REITS, C. von dcr (678) RESULTS 9? THE ANALYSIS OE GRAPE rOTCES AND TUCS PRODUCED EPOE V3TUBS ICH HAVE IEEE SFBAYED EI IE jE.VE AREENITE, I. Ber. Kgl. Lchr^st. Wein, Obst Gartentau, Gel^snheim-ar-- S^sir: , 1905: 22? „ II. Ibid., 1907: 176, (la Germar. kor.i.- c t in CSaom. Ato, 7: 2338, 1909.) The results show the arsenic content in the vine t and fruit. Most arsenic. 16 mg, in 100 g. , is found in the leaves and least in the berries, 0.7 mg. in 100 g. The Bureau holds that wine contain- ing 2 Kg. lead and. 1.5 (ma) arsenic per liter must be considered in- jurious to health. lie Analytical results are given foi grapes, grape .;aice and new wine grown under treatm nt with paris green, lead arsenitc, and arsenious acid r (679) OCCURRENCE CE JESEEIC IE GERMAN WINE. Per, KgL, Lehraiist, Eein Obst, &artenbau, Geisenheim-am-Ehein 1907: 180 (in German. Abstract in Biochem, Oentr. 8: 23a; also in One;, lbs, 3: 3338. 1S09.) When 38 wiaes of different localities *"ea analyzed, 28 aero found to contain perceptible amounts of arsenic, maximum 0.05 (mg?) arsenic in 100 cc, A higher percentage of the selected wines con- tained arsenic than of the cheap table wines, This may, however, be accidental. (5G0) AMOUNT CE ARSENIC IE GEAPES, MUST AND WINE RESULTING FROM TREATMENT CE THE VINES WITH ARSENICAL SEPAxS. Wein u, Robe 3: 515-528, 595- 59C. 1922 (In German, Abstract in Cham, .Eds, 17: 3399, 1923) Gathered grapes, pressed must, pressed marc, nem wine yoast, - 200 - marc-wine, and marc-wine yeast were tested for the presence of arsenic after tho vines had "been subjected to treatment with j.ead arsenato ("Zabulon") , calcium arsenate (Sturm's material), and copper acetoarsenite (Schweinfurth* S green or, if very finely divided, Urania green). Arsenic was detected in all the samples examined, even when it had not "boon administered to the vines. In general, grapos treated with Urania green contain more arsenic than those treated with "Zaoulon 11 , and rotten-ripe grapes more than normal ones. The proportions of arsenic present in the wines were 0.02-0.18 mg« per liter, and should be harm- less. The wine yeasts, however, contained as each as 0,lb5 g, of ar- senic per kg. of dry matter, such an ajaount being harmful to animals. With marc-wine yeast 0.1456 g, of arsenic per kg, was found. HENDERSON, J. B. (681) REPORT OE THE (QUJENSLAND) GOVERNMENT ANALYST EOS THE YEAR ENDING JUNE 30, 1928. Analyst 53: 652-653. 1923. Samples of cabbage which had been dusted with lead arsenate from 6 to 8 times were analyzed. Arsenic was found in amounts up to 240 p. p.m. (1.68 grains per pound) in the four outer leaves and up to 6 p. p.m. (0.042 grain per pound) in tho cross s3ction after removing the four outer leaves. Lead, was present in all samples. (662) REPORT OF TEE (QUEEN ELAND) GOVERNMENT ANALYST FDR THE YEAR ENDING JUNE 30, 1929. Analyst 54: 746-748. Many samples of cabbage examined contained high amounts of lead arsenate, 4 containing between 15 and. 17 grains. One, on which lead arsenate stains were visible, was boiled with salt and a little soda as is done ordinarily in the household. This process distributed the lead arsenate, of v/hich 15 grains Was present, even- ly throughout the cabbage and water. An ordinary 3-ounce helping of this cabbage would contain 0.25 grain of lead and 0.3?5 grain of arsenic pontoxide. A 9-ounce cupful of the water, which children have been urged to drink for the vitamin content, would contain 1.1 grains of lead and 0,6 grain of arsenic pontoxide. The maximum medicinal dose of arsenical for on adult is only 0.06 grain. (683) .REPORT OF THE ('QUEENSLAND) GOVERNMENT ANALYST FOR THE YEAR ENDING JUNE 30, 1930. Analyst 56: 32-33. 1931. Ten samples of cabbage contained lead arsenate in quantities ranging from 3.2 to 9.3 grains per cabbage. / - 201 - HENGL, F., KBGONBQRBXB, P., and BERAN, F. (684) USE OF ARSENIC AMD LEAD IN THE TREATMENT OF DISEASES OF THE VINE* Wein u. Rebe 13: 459-468.. 1932. (In German. Abstract in Chem. Abs. 27: 2524. 1933) Five weeks after spraying with lead arsenate, the grapes con- tained 0.-8 to 5 mg. of arsenic and 0.7 to 6 nig. of lead per kg; the must and wine contained 0.1 to 1 mg of arsenic trioxide and 0.2 to 1.4 (must) and 0.15 to 1 (wine) Eg. cf lead. HERMAN, F. A., and KELSALL, A. (685) THE DETERMINATION OF ARSENICAL RESIDUES 01! APPLE FOLIAGE. Sci. Agr, 8: 290-291. 1927. Sixty-three percent cf the arsenic applied as paste lead ar- senate is lost in the first 2 weeks, 58 percent from dry lead ar- senate and 40 percent from calcium arsenate. In the second fort- night the percentages lost Pre 17, 12 and 10 percent, respectively HODGKISS, H. E. (636) THE RELATION OF INSECT CONTROL TO USE ARSENIC CONTENT OF SPRAY' RESIDUES. Pa, State Hort. Assoc. News 8 (l): 18-27. 1931. The arsenical residue on 100 samples of Pennsylvania apples in 1930, a very dry year, ranged iron 0.000 to o 02 grain of arsenic trioxide per pound of fruit, 77 samples being "below the world tol- erance and 11 equalling or just exceeding it. A table is given which shows the amount of rainfall aft_.r the last spray and the a- mo ur.it of arsenic present on 10 samples cf apples Ordinary handling of apples caused a reduction of 0.003 grain p^r pound in the arsenical residue. and HALEY, D. E. (687) A STUDY OF ARSENICAL RESIDUES ON APPLES IN PENNSYLVANIA WITH RESPECT TO EFFICIENT SPRAYING PRACTICES, II. Jour, Econ, Ent. 24: 83-67, 1931. The amount of arsenic trioxide on apples from 100 Pennsylvania orchards ranged from 0.000 to 0.02 (grains) per pound. Of those samples, 75 were below the limit of 0,01 grain per pound. HUGUES, E. (688) SUR LA TENEUR EN CUIVRE DES VINS e Fro^., Agr. Vit. 95: 472-473. 1931. Not more than 0.5 ng. of copper par liter was found in wines from grapes which had been treated with copper salts. The work of previous authors, supporting the contention that only negli- gible amounts of copper arc nrescnt in such vines, is auoted<. - 202 - janicsbe::, m. :^89) the copper content cf drug- extracts resulting from insecticide sprays. Magyar Gyogy. Tarasag frtesit&ja' bJ 317-322. 1929 [In Hungarian. Abstract in Chan. Ahs, 23: 4770. 1929] A spray of 2 percent bordeaux solution and 1 percent "burgundy mixture was used. Samples of plants were taken after 2, 16 and 30 days. Copper was determined electrolytically in the 10 percent sul- phuric acid extract of the plant ash. By another method the dry plant powder was "boiled with dilute nitric acid, evaporated, concentrated sulphuric acid added and the mixture diluted. Copper was calculated to CuSO/p, 5h20, The copper content of Melissa o fficinalis amounted to about 2 percent, that of 11 en t h a c r i s p~ob alt o 5 percent". Plants contain much copper even after a month with ample rains. These copper compounds arc not dissolved by water gjad could "ba r-WQtred "by filtering. As plant extracts are usually not filtered, tozic copper compounds can thus get into the solution, KELSALL, A., and HERMAN, J, A. (690) THE PERSISTENCE OP A POISONOUS RESIDUE ON FOLIAGE SPRAYED V ITH NICO- TINE SULPHATE e Sci. Agr. 8: '±65-465. 1928 . Commercial nicotine sulphate (40 percent nicotine) used in sprays on foliage, leaves a fairl;/ persistent poisonous residue of the order of about 5 percent of the nicotine originally employed, EIELROFER, E Q (691) DER BLEIGEHALT VON MOST USD WEIN /.US TRAUBEN, DIE MIT 3LEIHALTIGEN' SCKADLINGSBSKIMPUN&SMITTELN BEHANDlLT WURDEN. Ztschr, Untersuch. Lebensmtl. 58: 382-386. 1929„ Wine from grapes previously treated with 2 load- containing in- secticides (Blarsenat Spiess and Zahulon Hinsberg) contained the fol- lowing average amounts of lead in mg. per liter; must 1,4 end 1,3; wine after the first drawing 1.0 and 1,1; wine after the second draw- ing 0.5 and 0.4;dregs 15.0 and 12.2* Pining of the wine with po- tassium ferrocyanide reduced the lead content only slightly. KOHN-ABRSST AND BOULIGAUD (692) PRESENCE ACCIDENTELLS DE L' ARSENIC, EN 1916. DANS L3S PRCDUITS CHIMIQUES USUSLS ET DANS QUEL^UES ALIMENTS* III. Ann, Chim. Analyt. 22: 128-134 1917. Arsenic was found in samples of wines obtained at random in Paris in amounts ranging from traces to 1.2 mg. per liter. The authors recom- ment a limit of 0.14 to 0.20 mg. of arsenic per liter of beer and 0.72 tc 1 mg. of arsenic per lit or < of wine. - 203 - LEHDRICE, K. (693) DIE 13EDLUTUUG DEli Se^LlNGSBEI&MPFUNG MIT AIlSiT UUD BLEI?EEBINDUNGEN IN DEE LAITDWIRTSC&AFT EJE DIE LEBENSMITTELVERSORGUNG. Arch, Fyg„ 100: 57-64. 1926, The amounts of lead and arser.ic fonnd on a number of samples of apples and grapes are reported. The quantity, especially of arsenic, found on American apples was Euch less for the 1927 crop (following the establishment of the arsenic tolerance "by the Federal Government) than for the 1925 and 1926 crops. . ari d IvLAYER, F. (694) TCEITEEE ERHEBUNGBK &B3E DAE TOISOMOT VON ARSEN, BLEI UND KUPE3E AITS OBST UND IF FINISH B22EUGNISSEN DARATJS ALE FClfrZ LEE SCidDLINGSBEKfePUNG, Ztschr, Untcrsuch. Lobensffitl. 54: 137-159, 1927, Humorous data arc prsaentod relative to the quantities of arsenic, lead and copper found on apples and pears from the United States, Canada, and Australia and on Gorman grapes.. LESCOEUE, :.', H fl (695) DS L'ARSENIC EH AGRICULTURE. L'Engrais 26: 1336-1337. 1911. Bert in- Sans found that grapes which had received arsenical treat- ment contained 0.006 mg. of arsenic per kg. and the wine from them con- tained 0.01 and 0.04 mg. per liter. Formally, 7, r im contains up to 0.003 mg. of arsenic per liter. Fine liters of the wine containing 0.04 mg. per liter would contain as much arsenic as one drop oi Fowler's solution. LOHGFIELD- SMITE, L. (696) REPORT 01 THE ARSENIC INSPECTION LABORATORY FOE THE SEASCH 1933. Fla, Qnar. Bull. 43 (1): 23-51. 1934. The application of lead arsenate sprays to citrus fruit troes on June 7 and 3 resulted in slight penetration of arsenic into the fruit: AjpOg in juice •'"■'? r '3 in ra S Fruit in p. e.g., in p. p.m. Grapefruit .005 (late December) Marsh seedless grapefruit .015 (Nov. 6) .06 (Nov. 6) Temple oranges .01 (late October .04 (Late October) H 11 q-]_ 11 11 t Q2 " " Tangerines .0005 mg.llOOoc. (Dec.) .0015 mg. 150 g. (Dec, Valencia oranges .02 (end of Doc.) .06 (end of Dec.) - 20 i - MARSHALL, G. E. (697) SPEAY EXPERIMENTS THIS PAST SUMMEH. Ind. Hort. Soc. Trans. 72: 16-25. 1932. The amount of residue on riped and unwiped apples at harvest after first-brood sprays of lead arsenate-liiae sulphur and second- "brood sprays of summer oil -f- nicotine, summer oil alone, lead arsenate, nicotine tanw nate, "barium fluosilicate 4- summer oil and summer oil -f oleic acid is given in a table, MAINE, W. W., NAEASIMHAN, M. J., .and SREENIVASM, E. H. (698) SPRAYING OP COFFEE IN SOUTH INDIA. Mysore Dept. Agr, Coffee Sxpt. Sta, Bull. 9. 69 pp. 1933. The amounts of copper on coffee leaves sprayed with bordeaux mixture and stickers was determined in June and in September (before and after the monsoon). The amounts of copper retained from the different mixtures over this period were: plain bordeaux, 42.5 £1.7 percent; lin- seed oil bordeaux, 47.01 £2.6 percent; resin soda bordeaux, 41.57 £2,06 percent; casein bordeaux, 55.01 * 3.1 percent, MEIEE, K. (699) ZUE AESENFEAGE, Schveia. Ztschr. Gbst-u. Weinbau 37 (26): 455-461. 1928. The results of load and arsenic analyses on fruit, untreated and sprayed with lead arsenate or calcium arsenate, are reported. Three lots of untreated fruit contained 0.02, 0.01 and 0.08 mg. of arsenic per kg. anc 0.0, 0,14 mg, and a trace of lead per kg., respectively. The lead in fruil sprayed with lead arsenate ranged from 0.0 to 0,61 mg, per kg, and the ar- senic from 0.01 to 0.21 mg. per kg. For lead arsenate with bordeaux mix- ture lead ranged from 0*20 to 0.69 and arsenic from 0.01 to 0.06 mg. per kg. For calcium arsenate lead ranged from a trace to 0.49 and the arsenic from a trace to 0.55 mg. per kg. (700) ZUE AESENFEAGE. Schweiz. Ztschr. Ofcst- u. Weinbau 39 (1-2): 62-66. Illus 1930. Lead and arsenic analyses of fruit sprayed with lead arsenate, calcium arsenate and untreated are reported. M0REAU, L., and VINET, E. (701) L'ARSENIATE DE PL0MB EN VITICULTURE. Compt. Eend. 150: 787-790. 1910; When grapes were treated with lead arsenate at the end of May, a little still remained on them when they were harvested but none was found in the wine ma.de from them. It was eliminated in the lees and pro"ba"bly also in the marc. - 205 - and VINET, E. (702) , COMMENT S»ELIMINE L'ARSENIATE DE PLOMB APPORTE PAR LA VENDANGE. Compt. Rend. Acad. Sci. (Paris) 152: 1057-1060. 1911. Wines from vines treated with lead arsenate "before blossoming contain only slight traces of arsenic and lead, usually of the order, when they exist at all, cf those found in wines from vines which have never received arsenical treatment. It may "be entirely otherwise when the vines are treated late, after "blossoming. MULLER, K. (703) DAS ( VERB0T DER VERWENDUNG BLEIHALTIGER MITTEL ZUR RSBSChIdLINGSBE- KAMPFUNG. Weinbau u. Kellerwirtschaft 7: 54-56. (Abstract in Zentbl. Bakt. (2) 79 (1-7): 151. 1929.) Amounts of lead from 0.5 to 17.8 mg. per liter have been found in musts from grape vines treated with lead arsenate. Lead is a slow poison, and the amounts found in must and wine are too high to be overlooked. The action of the government in forbidding the use of lead-containing agents for pest control in viticulture is to be commended as it will increase the value of German wine at home and abroad. O'GARA, P. J. (704) PRESENCE 0? ARSENIC IN FRUIT SPRAYED WITH ARSENATE OF LEAD. Science (n.*.) 33: 900-901. 1911. Arsenic remaining on fruit in storage which has been sprayed with lead arsenate causes spotting cf the fruit. A 10-gram sample of badly spotted apple skin showed 0.05 .mg, of metallic arsenic. One large Spitzenberg apple shewed a total of 0.3 mg. of arsenic calcula- ted as AsgOg. The fruits were carefully washed so as to exclude frcm analysis all arsenic that adhered to the surface. PERCIVAL, G. P., and POTTER, G. F, (705) AMOUNT AND VARIABILITY OF SPRAY RESIDUE ON NEW HAMPSHIRE BALDV.INS. N. H. Agr. Sxpt. Sta. Tech. Bull. 49. 15 pp. 1932. Numerous data are given showing the amounts of lead and arsenic residues found during 1927-1929, classified by spray schedule, and the arsenical residue classified by height on tree and side of tree. A correlation of 0.599 ^0.045 was found for the amounts of lead and of arsenic on the same individual fruits in 1927. The results obtained show that the sampling procedure as carried rut in most inspection work is comparatively inaccurate, and that to be reasonably safe the grower must plan on keeping his arsenical resi- dues down to about three-fourths of the tolerance. - 206 - REMINGTON, R. E. ■ ■ (706) A HITHERTO UNSUSPECTED SOURCE OF ARSENIC IN HUMAN 'ENVIRONMENT. Jour. Amer." Chem. Soc. 49: 1410-1416. 1927. Samples of American smoking and plug tobacco have "been found to contain from 0.05 to 0,27 grain of arsenic trioxide per pound. Approxi- mately half of the arsenic in pipe tobacco is evolved in the smoke and about half of- that in plug tobacco, is soluble in water. RELY, E. (707) UEBER ARSENHALTIGEN WEIN. Deut. Med. Wchnschr. 53: 1518-1519. 1927. The author found 3 out of 5 kinds of wine examined to contain ar- senic in amounts from slightly more than 0.1 mg. to about 0,05 mg. per lite Of the effect of wine containing such amounts there is little known and the question should be clarified. (708) BADISCHE ROTWEINE DES JAHRGANGES 1929 MIT BESONDERER BERUCKSICHTIGUNG IHRES ARSEN- UFD KUPFERGEHALTES. Ztschr. Untersuch. Lofcensmtl. 62: 513-516. 1931. Amounts of arsenic ranging from to 0.66 mg. per liter (average 0,1? and of copper ranging from a weakly positive test to 2.40 mg. per liter (average 0.84) were found in 6 samples of wine. ROSADO and SCTOMAYOR, A. de (709) THE. POSSIBLE EXISTENCE OF ARSENIC AND LEAD IN PEPPER FRUITS. Mon. Farm, y Terap. 35: 365-367. 1929. (In Spanish. Abstract in Chem. Abs. 24: 2810. 1930.) Sixty samples of pepper fruit from different localities obtained from plants which had been treated with lead and arsenic sprays while in bud were examined. In only 1 sample was a trace of either found. SCHATZLEIN, C. (710) A1SENIC CONTENT OF MUSTS AND INFLUENCE OF THE ADDITION OF SULPHUR ON THE ELIMINATION OF ARSBNIC DURING FERMENTATION. Pfalz.-Wein 12: 23- 27. 1924. SHUTT, F. T. (711) EXAMINATION OF CANADIAN SPRAYED APPLES FOR ARSENIC. Analyst 51: 291- 292. 1926. Forty-three samples of Canadian apples were analyzed (skin, calyx and stalk). Approximately one-half were entirely free from arsenic; one-sixth showed traces less that l/lOOOO of a grain per - 207 - pound and one third contained arsenic ranging from i/lOOOO to l/l90 grain per pound; l/l90 of a grain per pound was the heaviest amount found. (712) FSPORT OF THE DCMINION CHEMIST, CANADA DEFT. AGE., FOE THE YEAR ENDING MARCH 31, 1927. 84 pp. Ottawa. 1928. Among 48 samples of Canadian sprayed apples examined in 1925, the heaviest arsenic load was l/l90 grain per pound. Of 56 samples analyzed in 1926, 95 percent contained arsenic in amounts less than l/lOO grain per pound, SLATE, W. L. (713*) EEPOET OF THE DIRECTOR FOE THE YEAR ENDING OCTOBER 31, 1931. Conn. Agr. Expt. Sta. Bull. 337: 449-493. 1932. The amount of arsenic on Connecticut apples was far "below 0.012 grain per pound. Although such favorable results were shown, growers were wn.rned that unusual conditions may occur when the fruit will have extra amounts of residue and such emergencies should "be prepared for. (p. 453) SMITH, R. C. (714) AN INVESTIGATION OF SPRAY COVERAGES AND ARSENICAL RESIDUE IN RELATION TO THE CONTROL OF THE CODLING MOTH. Jour. Econ. Ent. 21: 571-588. 1928. Numerous data are presented showing the average surface area per apple, the average quantity (mg.) of arsenic trioxide per apple, the average quantity (Micrograms) per sq« cm. of apple airface, and the average quantity (grains) of arsenic trioxide per pound of apples as ascertained "by mea- surements and analyses made "before and after each cover spr^.y and at - -r harvest. The average quantities (micrograms) of arsenic* trioxide in the outer and Inner calyx cups are also given, SONNTAG, G. (715) 2U DSR VERW3NDUNG VON ARSEN UND BLEI ENTKALTENDEN PFLANZENSCHUT2MITTELN. Art. Kaiserl. Gesundheitsamte 49: 502-520. 1914. After spraying of fruit trees and "bushes with arsenic-containing "bordeaux mixture, arsenic was found in ponderable amounts on currants and gooseberries, 41 tD 51 days after a single spraying; on 8 of 9 sam- ples of apples and pears, 87 days after spraying twice; on 2 samples of pears sprayed once heavily, 110 days after treatment; on leaves, 27 days after a single spraying. After spraying with le*».d and arsenic, weighable amounts were found as follows: arsenic on 6 and lead on 5 of 7 samples of stone fruit 24 - 208 - days after spraying; arsenic and lead on 2 samples of gooseberries and currants (l each) 39 days after spraying; arsenic on 3 and lead on 1 of 3 samples of apples and pears 80 days after spraying. After dusting with arsenic*- sulphur powder, arsenic and copper were found in weighable amounts as follows; arsenic on 7 and copper on 4 of 7 samples of stone fruit 24 days after dusting; arsenic on 4 samples of gooseberries and currants (2 each) and cc?per on 2 samples of gooseberries and one of currants 39 days after dusting; arsenic and copper on 4 sam- ples of pears and apples 106 days after dusting. SPALLINO, R. , (716) SULLA' PRESSN2A PEL BAPJO E DELL'ARSENICO NEI TABACCHI LAVORATI ITALIANI. Gaz. Chim. Ital. 43: 475-481. 1913. Quantities of arsenic ranging from 0.16 to 0.40 mg. per 100 g. of dry materialwere found in Italian snuff and from 0.08 to 1.02 mg. per 100 g. in Italian smoking tobacco. SUTTON, G. L. (717) TESTS TO DETERMINE THE PRESENCE OF ARSENIC IN APPLES AETER TREATMENT WITH ARSENICAL SPRAYS. W. Australia Dept. Agr. Jour. (2) 3: 221-225. 192 The amount of arsenious oxide on Australian apples from 3 orchards which had been sprayed from 1 to 3 times with lead arsenate ranged from l/3600 to l/800 of a grain per pound. The amount en apples from an orcharc sprayed 5 times with lead arsenate and calcium caseinate ranged from 1/80C to l/l60 of a grain per pound. SZAMEITAT, A. (718) REPORT OF ANALYSES, MUSTS AND WINES FROM GRAPES OF VINES SPRAYED WITH ARSENIC COMPOUNDS. Ber. Kgl. Lehranst. fur Wein- Obst- u. Gartenbau. Geisenheim. pp. 176-179. 1907. (In German. Abstract in Chem. Aba. 3: 685. 1909.) The vines were sprayed with bordeaux mixture to which was added paris green, or lead arsenate, or copper arsenate, or arsenic acid, or a l/2 percent solution of arsenic-acid-copper mixture, or dusted with a mixture of 4 parts gypsum and 1 part copper arsenite. The analyses gave in most cases a slight trace, in 3 cases none, and in 2 cases 0.3 mg. arsenic from 100 g. of grapes; the results were identical for 100 cc. of must; and in 3 cases a slight trace in 100 cc. of new wine. TAYLOR, J. J. (^19) STATE CHEMIST'S REPORT, 1932. Fla. Quar. Bull. 42 (l). 246 pp. 1933. The results of analyses of 548 samples of celery and 31 sam- ples of cabbage for arsenic are reported, (pp. 35-38). - 309 - "'■' '• TROFIMENKO, M. , and OBIEBQFF, S. ' t (720) LE VIN DES RAISINS s TRAILS AUX ARSENIATES''CONTRE LA 2 m © GENERATION DES INS3CTES. Pr ogres Agr. et Vitic, 65: 331-333. 1916, Although the grapes used contained arsenic "because of late treat- ments against the second generation of insects, and although the opera- tions of fermentation were carried out in a manner to assure the "best conditions .for the arsenic to remain in the wine if possible , yet ar- senic was absolutely absent in white wine and was present only in insig- nificant traces (0.2 mg, per liter) in red wine. VIALA and BLANCHARD, E. (721) LES ARSENICAUX EN ARBORICULTURE FRUITIERE. Gompt. Rend. Acad. Agr. France 19: 180-186. 1933, Lifting of the ban on the use of arsenicals in arboriculture is urged. The amount of metallic ar^stiiQ foand^ oxrp<3&r&- jrhiofc kad" received . from 3 to 8 arsenical treatments ranged from 0.19 to 4 mg. per kg. of fruit, > • VIALA, P., and MARSAIS, P. (722) NOUVELLES RECHERCHES SUR LES DOSXS D' ARSENIC, LE CUIVRE ET LE NICOTINE, CONTINUES DANS LES PRODUITS LE VIGNES TBAITEES TARDIVEMENT COfTRB LES VERS DE LA GRAPPE. Rev. Vit. 68: 233-236. 1928. Vines were treated about a month before gathering with lead arsenate and with nicotine added to bordeaux mixture. Wines from these grapes con- tained from a trace to 1.54 mg. of arsenic per liter, from 21 to 32 mg. of nicotine per liter, and from traces to 62 mg. of copper per liter. The lees contained more than the wines in each case. WHITCOMB, W. D. (723) THE PLUM CURCULIO IN APPLES IN MASSACHUSETTS, Mass. Agr. Expt. Sta. Bull. 249. 52 pp. 1929. Under Massachusetts conditions, the amount of arsenic trioxide on fruit at harvest is well below 0.01 grain per pound following any of the recommended spray schedules. Even where fish oil was used, residues of 0.0036 and 0.0035 grain were found. WOODS, C. D. (724) FIELD EXPERIMENTS. Me, Agr. Expt. Sta. Bull. 224. 48 pp. 1914. The amount of lead arsenate fnund-at harvest on apples which had been sprayed the first week in August was determined by washing the apples thoroughly in water and determining lead and arsenic in the washings. Analysis of two lots of peels after washing indicated that this treat- ment removed all of 'the lead arsenate. The arsenate of lead calculated - 210 - from the arsenic was about a half more than that calculated from the lead found. The amount of lead arsenate found on these apples 60 days or longer after spraying Varied from 0.140 to 0.454 mg. per apple, cal- culated from the arsenic, and from 0,108 to 0.292 mg. per apple, calcualtec from the lead. "This amount is insignificant and no harm could come from the continued use of apples carrying this amount of arsenate if no precautions were taken whatever in removing it from the skin if the parings themselves Here eaten*" YOCUM, W. W. (725) THE 1929 SPRAY EXPERIMENTS AT SHUBERT. Neb. State Hort. Soc. Ann. Rpt. 61; 47-51. 1930. Eight samples' of. apples from each of 3 Department of Horticul- ture orchards were analyzed for arsenical spray residue. The largest amount found was 0.0062 grain of arsenic trioxide per pound. .VII, GENERAL AND UNCLASSIFIED ARTICLES ON THE SPEAY RESIDUE PROBLEM. ANONYMOUS. - (726) DESTRUCTION DES PARASITES NUISIBLES A L« AGRICULTURE. Rev. Agr. Afr. Nord 18 (59): 223. 1920, The Minister of Agriculture has decided that winter treatments of vines and fruit trees with soluble arsenical compounds may be made up until May 1, 1921. (727) EMPLOI DES ARSENICAUX EN AGRICULTURE. Bui. Soc. Agr. France. 54 (8): 25f 1922. The periods during which treatments with insoluble arsenicals are authorized for various crops by the Minister of Agriculture, as of July 7, 1922, are given. (728) PR0T0KOLL DER KONEERENZ ZUR BESPRECHUNG DER BSDEUTUNG UND ANWENDUNG VON ARSEN - UND BLEIGIFTEN GEGEN OBST - UND WEINBAUSCHSDLINGE. Schweiz. Ztschr. n Ds t - u. Weinbau 34 (8): 137-150. 1925. (729) ARSENICAL RESIDUES ON APPLES. Agr, Insecticide & Fungicide Mfg. Assoc. Bull. 5: 22-29. 1926. Several letters are reproduced which relate to the seizure in Kansas of some apples alleged by the Federal Government to be adulter- ated with arsenical poison. - 211 - (730) (REPORT OF) 390th MEETING. Jour. Wash. Acad. Sci. 17; 404-406. 1927. A symposium on arsenical spray residue conducted "by Dr. A. L. Quaintance is reported. ANONYMOUS (731) ARSENICAL SPRAY RESIDUE PROBLESM. Chemicals 29 (18): 8-9. 1928. A discussion before the American Chemical Society Section of Agricultural and Food Chemistry is reported. (732) SPRAY RESIDUE. Calif. Dept. Agr. Mo. Eull. 17: 294.- 1928. Fruit growers are urged to continue care in cleaning all fruit previous to shipment, regardless of its spray history. Any condemna- tions made for infractions of the spray-residue regulations would act . detrimentally to the entire fruit industry. (733) THE STORY OF A. DIRTY APPLE. Better Fruit 23 (12): 13, 28. 1929. A "brief outline of the development of spray-residue removal* ... (734) FACE TO FACE V/ITK SPRAY RESIDUE SITUATION. Fruits and Gardens 28 (2): 3, 1930. An editorial warning that the arsenic tolerance will probably be gradually lowered to 0.01 grain per pound of fruit, the "world tolerance", and tfisSift washing of apples ; will be necessary, ■ , ■■ , (735) RESIDUE PROBLEM BECOMES MORE IMPORTANT. Amer. Fruit Grower Mag, 51 (12): 11, 1931. A brief article based on the Annual report of Dr. C. L. Marlatt, Chief of the Bureau of Entomology, to the Secretary of Agriculture. . (736) ARSENIC SPRAY SITUATION. Citrus Indus. 14 (5): 10. 1933. An editorial advising citrus growers to urge the State legisla- ture t» repeal the anti-arsenic law for citrus fruits. - 212 - . (737) SPRAY RESIDUES. Market Growers Jour. 52: 92. 1933. During the last season cauliflower growers throughout the coun- try ran into trouble through condemnation of shipments for excess ar- senic. CLARK, W. R. (738) REPORT OF COMMITTEE ON SPRAY RESIDUE. N. Y. State Hort. Soc. Proc. 79: 231-232. 1934. A report of the activities of the committee in getting all available information and in attempting to have the tolerance lowered. CONFEDERATION GENERALE DES VIGNERONS (739) VOEUX DE LA CONFEDERATION DES VIGNERONS. Rev. Vitic. 47: 15. 1917. Authorization of the use of soluble arsenical salts under the same condition as the insoluble salts in viticulture is requested, COOPER, T. (740) (UNWASHED APPLES POUND TO CONTAIN ARSENIC ABOVE TOLERANCE.) Ky. State Hort. Soc. Trans. 78: 129-131. 1933. The experiences of a grower who tried to ship to market apples bearing amounts of arsenical residue above the tolerance. CULPEPPER, C. W. and MOON, H. H. (741) SULPHUR SPRAY RESIDUES AND THE SWELLING OF CANNED PEACHES. Canning Age 9: 461-462. 1928. The presence of very small amounts of sulphur (in the form of spray residue) in canned peaches causes extensive corrosion of the cans with consequent swelling of the cans by hydrogen. and MOON, H. H. (742) SULPHUR-SPRAY RESIDUES AND THE SWELLING OF TIN CANS PACKED WITH PEACHES. Jour. Agr. Research 39: 31-40. 1929. Sulphur-spray residues are sometimes rather difficult to remove from the surface of peaches. The presence of this sulphur in the can causes the formation of hydrogen sulphide and hydrogen gas, with conse- quent swelling of the can. Dipping the fruit in hot dilute lye for a few seconds and then washing the fruit with jets of cold water is effec- tive for removing the spray residue. The sulphur also has a corrosive effect on the can. - ,213 - DAVIS, JT, K. (743) IMPROVED WORM CONTROL BIG GOAL. Better F r uit 22 (7): 7. 1928. A report of discussions at the meeting of the 7/ashington HorticuL* tural Society in December, 1927. Heald, Diehl and Fisher are qnoted ©n the subject of fruit washing for spray residue removal. DURST, C. E. (744) RAMBLES OF A HORTICULTURIST ON THE PACIFIC COAST. Iowa State Hort. Soc. Trans. 61: 58-63. 1926. Due to demands of British authorities that fruit carry less than 0.01 grain of arsenic per pound, growers in the Pacific North- west and California are planning to wipe their fruit. EARNSHAW, J. F. (745) SPRAY RESIDUE CONTROL OF VIRGINIA APPLES. Va. Fruit .2 (l): 40. 1934. A letter written "by D. M. Walsh was read which suggested a coop- erative agreement among the fruit growers, the Virginia Dairy and Food Division, Division of Markets and Division of Chemistry and the Federal Food and Drug Administration as to sampling, analysis, and control of fruit. ELLETT, W. B. and HILL, H. H. (746) INVESTIGATIONS IN AGRICULTURAL CHEMISTRY. Va. Polytech. Rpt. 1919- 1927. pp. 22-34. 1928. Somo varieties of apples examined showed amounts *f arsenic which would prohibit their shipment in inter-state traffic. It seems imperative that some method for the removal of arsenic should be used. Study shews that wiping and brushing methods are unsatisfactory. The arsenic can be removed by dipping the fruit in a 2.5 percent solution of hydrochloric acid at ordinary temperature. and MILLER, M. P. (747) THE REMOVAL OF SPRAY RESIDUE FROM APPLES. Va^Iblytech. Eept. for 1919- 1927. pp. 142-148. 1928. Varying strengths of hycrochloric acid, sodium hydroxide and salt solutions were employed for washing arsenic- sprayed apples. Two and one-half percent hydrochloric acid will remove over 90 percent of the arsenic in five minutes below 70° F. At strengths of 2.5 and 5 percent the acid removes all signs of spray residue when lead arsenate alone or plus bordeaux is used. One percent hydrochloric acid removes over 50 percent of the arsenic at ordinary temperatures. Five percent solution of sodium hydroxide removed 80 to 85 percent of the arsenic. Sodium hyposulphite was unsatisfactory. Sodium chloride and sodium car- - 214 - bonate, 4 percent of each at 100° F., was effective. Hand wiping or treat- ment with water was unsatisfactory* FLINT, W. P. . (748) EXPERIMENTAL WORK OF THE NATURAL HISTORY SURVEY ON CODLING MOTH. 111. n State Hort. Soc. Trans. (1926) 60: 109-120. 1927. "'hen the season is dry during the latter part of the summer and early fall, it is probable that more than the tolerated amount of spray residue would "be present on fruit that had "been heavily sprayed in August, Reports from the Northwestern States indicate that "brushing alone cannot "be relied upon to remove the excess spray residues and it seems' probable that the only way they can be taken off is by passing tho fruit through a bath containing certain chemicals, FROUMENT, R. (749) MOYENS DE LUTTE CONTRE L'EUDEivIIS. Pr ogres Agr. et Vitic. 75:- 566-573. 1921. The legal limitation of the use of arsenates is protested, HEBERT, J. W. (750) DISCUSSION OF THE SPRAY RESIDUE SITUATION. Wash. State Hort. Assoc. Proc. 23: 131-137. 1927. The activities of the Northwest Spray Residue Committee are reported. (751) ARSENATE OF LEAD SITUATION. Wash. State Hort. Assoc. Proc. 22: 7-9. 192 Every effort has been made to prevent undue publicity concerning the spray residue situation for fear of the unfavorable reaction that might result. A long speech by Hebert on the subject is briefly outlined. The historical development of the situation was discussed. The measures taken and the plans of inspection adopted were described. The futility and danger of the industry's seeking to evade the issue was stressed, HERMS, W. B. (Chairman of committee) (752) PROGRESS REPORT OF COMMITTEE TO INVESTIGATE ARSENICAL RESIDUES ON FRUITS AS THE RESULT OF SPRAY PROGRAMS. Jour. Econ. Ent. 20: 30-31. 1927. Lines of attack on the spray residue problem that have be t en em- ployed in many of the fruit .growing districts where codling moth control is necessary include: 1, Control of the first brood of moths. 2. Making early sprays more effective. 3, Removal of residue by either mechanical or chemical means, 4, Supplemental methods: a, Banding tress; b, Orchard and packing house sanitation; and c, baiting moths. 5. Substitutes for arsenicals. - 215 - HERRICK, G. W. (753) SFEAY RESIDUE ON AFPLES. Rural New Yorker 92: 434-435. 1933. A "brief discussion of the spray residue situation, HILL, K. (754) ECONOMIC PHASES OF THE SPRAY-RESIDUE PROBLEM. Wash. State Kort. Assoc, Proc. 29th Ann. Meeting 1933: 17-20. The author urges a fight "by the Northwest fruit industry to keep the tolerance (for lead) at or above 0.02 (grain per Id.), iHODGKISS, H. E. (755) CODLING MOTH AND ROSY APHIS SUPPRESSION. Penn. State Hort. Assoc. Proc. 75th Ann. Meeting; Penn. State Hort. Assoc. News 11 (l): 50-60. 1934. Results of lead analyses on Pennsylvania apples indicate that thought must be given to residue removal. HOUSER, J. S., and OUTRIGHT, C. R. (756) THE CODLING MOTH. Ohio State Hort. Soc, Proc. 16th Ann. Meeting, Jan. 3C~ Eeb. 2, 1928. Vol. 61, pp. 115-125. A brief outline of the spray residue problem is given. HOWARD, L. 0. (757) REPORT OF THE ENTOMOLOGIST. U. S. Dept. Agr. 29 pp. 1927. Investigations in connection with the problem of arsenical spray residues on apples and pears arc being carried on cooperatively by the Bureau of Entomology, Bureau of Plant Industry, Bureau of Chemistry and Soils and several of the States. KJOSNESS, A. W. E. (758) ARSENICAL SPRAY RESIDUE SITUATION IN IDAHO. Idaho State Hort. Assoc. Proc. 32: 59-63. 1927. A review of the activities of the Idaho and the United States depart- ments of agriculture during the past year (1926) with regard to arsenical residue on fruit. KOEHNE, F. J. (759) MEETING THE SPRAY RESIDUE SITUATION, Ind. Hort. Soc. Trans. 73: 82-85. 1934. A general discussion. - 216 - MAGNESS, J. R, (760) SPRAY RESIDUE AS A NATIONAL PROBLEM. Wash. State Hort. Assoc* Proc. 23: 121-125* 1927. ' The problem of the apple producer in different sections of the United States is discussed. The history of the efforts made up to 1927 for the removal of spray residue from fruit is briefly sketched. Pry cleaning is ineffective. Acid and alkaline washes have been found ef- • • fective in removing arsenical residues from pears and early and mid- season varieties of apples. Late, more waxy varieties, such as Arkansas Black and Y/inesap, are more difficult to clean. Different brands of lead arsenate vary in the ease of removal. There is some indication that the use of lime in the spray makes its removal less difficult. MAGNUSON, K. P. (761) ■ SPRAY RESIDUE REMOVAL LOOMS WITH TROUBLE FOR CRCHAEDISTS* Univ. Idaho Coll. Agr. Hews Letter 18 (5):- 1, 2. 1934. One and one-half percent hydrochloric acid or sodium silicate at a concentration of 70 to 90 lbs. per 100 gals, of water continue to be the basic washing solutions for the removal of lead, arsenic and fluorine. Vat sol, porno, and other washing agents can be used with the acid wash to increase the efficiency. Soap should be added in small amount to silicate washes. For fruit difficult to clean a double wash of sodium silicate followed by hydrochloric acid is recommended. MARLATT, C. L. (762) REPORT (1927-1928) OP THE ENTOMOLOGIST, U. S. Dept. Agr. 34 pp. 1928. The rapid progress in the perfection of apple-washing machines indicates rather strongly that the use of such machines to remove ex- cess spray residues will prove a most valuable means of meeting the residue problem. Should this be the case the continued use of lead arsenate, even under arid conditions, will be possible. NILES, B. E. (763) THE ARSENICAL RESIDUE TOLERANCE. Ky. State Hort. Soc. Trans. 761 104- 107. -1931. Difficulties have been experienced in interstate shipment of un- washed fruit, ever, when residue was below the tolerance. O'BRIEN, H. R. (764) PROGRESS IN BUG POISONS. Country Gentleman 103 (10): 10, 11,-64. 1933. Because of the stringent regulations concerning lead residues, now insecticides are being developed in the hope of replacing lead ar- senate. - 21? - (765) FRUIT '.7ITH0UT BLEMISH. Country Gentleman 104 (5): 10-11, 44-45. 1934. This article gives a popular and not very accurate account of the spray residue situation. P., F. (766) L» INTERDICTION DE L'EMPLOI DSS COMPOSES ARSENICAUX SOLUBLES EN VITICUL- TURE. Rev. Vitic. 45: 247-248. 1916. Viticulturists of Prance and Algeria have protested against the regulation forbidding the use of soluble arsenic compounds in agricul- ture. PARKER, T. (767) ARSENIC IN PRUIT? Fed. Brit. Growers Jour. 2: 193. 1923. Using lead arsenate paste containing 15 percent arsenic pentoxide at the rate of 4 lbs. to 100 gals, of water arid assuming that it takes 1 gal. to spray a tree yielding an average of 40 lbs. of fruit, 5 full grown apples weighing 1 lb., then there would be l/5 grain of arsenic pentoxide applied per apple, if all actually fell upon the apples. In reality, a much greater portion goes on to the tree and foliage than on the fruit. In experiments carried out to determine whether grapes, pears, cabbage and gooseberries sprayed wi th lime and paris green, with or without a sticker, retained sufficient arsenic to be harmful to health, samples were taken at intervals beginning a few weeks after spraying and ending when the material was ready for consumption. No trace of arsenic could be found on grapes. No arsenic was found one month after spraying except in one case where a slight deposit was found. No spraying should take place within six weeks of actually picking fruit. PARKER, T. (768) INSECTICIDES— ARSENICAL AND OTHERWISE. THE "APPLE SCARE" AND ITS LESSONS. Chem. Trade Jour. & Chem. Engin. 78: 251-253. 1926. The occurrence of excessive arsenic on American apples is men- tioned. The use of arsenicals for codling moth control is discussed, with a comparison of English and American spraying practice. Possible means of minimizing the arsenical deposits on fruit are: wiping the fruit prior to packing, the use of non-poisonous insecticides, attack- ing the pest at a stage in its life history other than the larval stage. PETHERBRIDGE, F. R. , and THOMAS, I. (769) THE CONTROL OF THE RASP3ERRY BEETLE. Jour. Ministry Agr. 39 (ll): 1017- 1028. 1933. (Abstract in Rev. Appl. Ent. (A) 21: 170-171. 1933.) Experiments on the control of Byturus tosientus F, were carried out on loganberries and raspberries with lead arsenate (2 lbs. to 100 - 218 - gals*). When one spray was applied at full "bloom, the damage was re- duced but a deposit of the arsenate was left on the fruit. POSTLE, S. A. (770) SPRAY RESIDUE. Ky. State Hort. Soc. Trans. 75: 64-76. 1930. A discussion of the spray residue situation, participated in by members of the society. CJJAINTANCS, A. L., CHILDS, L # , BEAN, G. A., PORTER, B. A. , PARROTT, P. J., and ROSS, U. A. (771) REPORT OP COMMITTEE TO FOHLIULATE PLANS FOR INVESTIGATIONS OP THE CODLING LIOTH PROi: BIOLOGIC AMD CONTROL STANDPOINTS. Jour. Scon. Ent. 24: 18-23. 1931. Spray residues, .both in the Northwest and east of the Rocky fountains, were higher than usual during the season of 1930. RAUCOURT (772) RECHERCHES CHIMlQUSS SUE LES TRAITEMENTS ARSENICAUX DES ARBRES FRUITIERS. Compt. Rend. Acad. Agr. France. 20: 714-717. 1934. Analysis of the leaves and fruit of trees sprayed from one side with a suspension of commercial dilead arsenate containing 1 g. of arsenic (As) per liter gave the following results: On the day following the treatment, the leaves on the side of the tree from which spraying took place contained 6.8 micrograms of arsenic (As) per sq. cm. and the apples contained 28 mg. per kg. On the opposite side of the tree the amounts found were 0.5 micrograms of arsenic per sq. cm. of leaf and 5.8 mg. per kg. of apples. After 15 days there wore 2.4 micrograms per sq. cm. and 3.9 mg. per kg. on the sprayed side and 0.5 microgram per sq. cm. and 0.6 mg. per kg. on the opposite side. ROARK, R. C. • (773) CHEMICALLY COi/lBATING INSECT PESTS OF FOODSTUFFS. Indus, and Engin. Chcm. 24: 646-648. 1932. The problem of arsenical and fluorine insecticide residues is briefly mentioned. (774) INSECTICIDES AND FUNGICIDES. Ann. Survey Amcr. Chcm. v. 8, chapter 17, pp. 221-242." 1933. Literature published in the United States during 1933 relative to spray residues and their removal is briefly reviewod. - 219 - SARCOS, 0. (775) L'EUPLOI DES EMULSIONS ARSENICALES, EN HIVER. Rev. Vitic. 46: 229-233. 1917. Authorization of the use of emulsions of soluble arsemicals on vines during the winter is urged. SEMICHOU, L. (776) EMPLOI DES COMPOSES ARSENICAUX EN VITICULTURE. Rev. Vitic. 45 (1169): 338-341. 1916. .... Authorization of the use of soluble arsenic als on vines during the winter is urged. STEVENSON, A. E. (777) TEE EEPECT OE LIME- SULFUR SPRAY IN CANNED CHERRIES. Canning Age, Con- vention Digest 1926, pp. 248-250. (Abstract in Chem. Abs. 20: 1287. 1926.) An investigation is reported with an experimental pack of cherries subjected to the lime-sulfur spray. The results show how to guard against any danger of hydrogen springers. ST0CK5ERGER, W. W. , and COLLINS, W. D. (778) THE PRESENCE OP ARSENIC IN HOPS. U. S. Dcpt. Agr. Bull. 568. 7 iap. 1917. The spraying materials in general use, such as solutions of whale-oil soap and quassia or nicotine sulphate, are not to "be held responsible for the contamination of hops with arsenic. The sulphur in use in 1914 and 1915 was generally contaminated with arsenic, often over 100 p. p.m. When such sulphur is used in curing hops, the hops may contain 3 or 4 parts of arsenic per million. There is little doubt that impure sulphur alone is responsible for the contamination of hops with appreciable quantities of arsenic. TAYLOR, W. A. (779) REPORT OF THE CHIEF OF THE FuREAU OF PLANT INDUSTRY. U. S. Dept . Agr. 43 pp. 1927. Because of the reaction of export and domestic markets to the presence of arsenical spray residues on fruit, the problem of removing such residues so that the quantity remaining would be within a speci- fied tolerance was very definitely projected into the problem of hand- ling and marketing apples and pears. - 220 - THOMPSON, P. (780) REPORT OF THE DIVISION OF CHEMISTRY FOR 1927. Bull. 16: 724-727. 1927. Calif. Dept . Agr. Mo. The situation with respect to spray residue on fruits and vege- tables in various sections of California and the activities of the Divi- sion of Chemistry in enforcing the Federal regulations are briefly dis- cussed. VREELAND, C. D. (781) ARSENICAL RESIDUES ON FRUIT. Agr. Insecticide and Fungi cido Mfrs. Assoc. Bull. No. 6: 24-26. May 1927. A brief discussion of the attitude tov/ard fruit washing on the Pacific coast. WHARTON, W. R. M. (782) THE ARSENIC SPRAY RESIDUE PROBLEM. Peninsula Hort . Soc. (Del.) Trans. 45: 89-98. 1931. The history of the development of the spray residue problem from a law enforcement standpoint is traced. The economic advisability and the legal necessity for compliance on the part of the fruit growers with the tolerance for arsenic spray residue is stressed. (783) THE ARSENIC SPRAY RESIDUE PROBLEM. Del. State Bd. Agr. C^ar. Bull. 21 (5): 89-98. (1932?) The history of the spray residue problem, as it developed from a law enforcement standpoint, is traced. The economic advisability and the legal necessity for compliance by fruit growers with the arsenic tolerance is discussed and the position of the Federal Food and Drug Administration concerning the health considerations involved is stated. WHITE, W. B. (784) POISONOUS SPRAY RESIDUES ON VEGETABLES. Indus, and Engin. Chem. 25: 621-623. 1933. 'The reckless use of insecticides, the safeguarding of the public against poisonous residues, and analytical methods for the determination of lead and fluorine in residuos are briefly dis- cussed. _ 221 - (785) OUTLINE OF U. S. SPRAY RESIDUE HISTORY. Mimeographed paper di stributcd "by Dr. White at Boston Meeting, Dec. 1933. 4 pp. Important events in the history of the spray residue situation in the United States from 1900 to 1933 are outlined. Results of ar- senic and lead analyses on apples from different parts of the country are reported in tables. (786) THE CURRENT SEASON'S EXPERIENCE I IT ENFORCING SPRAY RESIDUE TOLERANCES. Jour Econ. Ent. 27: 125-132. 1934. Discusses the situation as to lead removal, the toxicity of fluorine, and the status of substitutes for lead arsenate. iliiii •» 1262 09224 6684