CENTER FOR STUDY OF RESPONSIVE LAW, Senator PHILIP Hart, DEAR SENATOR HART: May we commend you and the Senate Commerce Committee for investigating so thoroughly the hazards presented by weed-killer 2,4,5-T. It was encouraging to see USDA relent and prohibit certain uses of the chemical. However, after this brief commendation, we would like to make clear our feeling that the bans on 2.4.5-T were inadequate, and the press release announcing the ban misleading to the public. According to the official press release. "In exercising its responsibility to safeguard public health and safety, the regulatory agencies of the Federal Government will move immediately to minimize human exposure to 2,4,5-T and its impurities. The measures being taken are designed to provide maximum protection to women in the child-bearing years by eliminating formulation of 2,4,5-T use in household, aquatic and recreational areas (emphases added)." We contend that the measure taken reflect an utter disregard on the part of the USDA for public health and safety and represent minimal rather than marimal protection. 1. The use of Silvex (also called 2,4,5-TP; 2-(2,4,5-trichlorophenoxy) propionic acid) has not been suspended. Silvex is as closely related to 2,4,5-T as pancake are to waffles. Because of this similarity one can predict with confidence that Silvex will prove to be about as teratogenic as 2,4,5-T. Furthermore, the series of chemical reactions by which Silvex and 2.4,5-T are made are almost identical. These reactions lead unavoidably to the formation of the dreaded tetra-dioxin contaminant. If any serious attempt were being made to "minimize human exposure" to hazardous weed-killers and the impurities contained therein, the home use of Silvex would certainly be banned. Silvex, incidently, is a more common ingredient in garden products than is 2,4,5-T. 2. “Minimizing human exposure to impurities in 2,4,5-T and its impurities" would demand an immediate, total recall of 2,4,5-T and related compounds from retail stores and homes (with the manufacturers reimbursing stores and consumers). Although the USDA has called for recall in a private communication to manufacturers, no recall will be complete unless the announcement is published in the Federal Register and a list of products containing the dangerous substances is published in newspapers so that consumers may return what they had previously purchased. 3. "Minimizing human exposure" to impurities in 2,4.5-T would necessitate suspending the use of 2,4-D (the most widely used weedkiller), 2,4-DP (found in Scott's Turf Builder Plus 4), and pentachlorophenol (present in Ortho Triox Liquid Vegetation Killer). The processes by which all three of these compounds are made lead unavoidably to formation of dioxins. 4. "Minimizing exposure to 2,4,5-T and its impurities" would necessitate suspending all uses and formulations of all chlorophenoxy and chlorophenol weedkillers: (a) The possible persistence of dioxins represents a very real danger, as pointed out by Drs. Verrett and Epstein, Mr. Bickwit and ourselves at the Commerce Committee hearings. (b) Accidental exposure to the weed-killers or their contaminants due to direct spraying, drift or residues on food is possible, indeed inevitable, when these weed-killers are used on crops, ranges, rights-of-way, neighbors' yards, etc. In testimony before the House Subcommittee on National Security and Scientific Developments on December 2, 1969, Dr. Arthur Galston of Yale University said, “I suggest that its (2,4,5-T) teratogenicity is such that even its use in such apparently innocuous domestic manners as clearing brush near powerlines is undesirable. Such chemicals could find their ways into water supplies and could be ingested in teratogenic doses.” If the regulatory agencies truly wish to exercise their responsibility to safeguard public health and safety, particularly that of women of childbearing age, by minimizing human exposure to 2,4,5-T and its impurities they will certainly have to go far beyond the recently announced minimal actions. If possible we would like this letter made part of the hearing record. Sincerely yours HARRISON WELLFORD. JAMES TURNER. STATEMENT OF R. L. CUSHING ON BEHALF OF THE HAWAIIAN SUGAR PLANTERS' ASSOCIATION, HONOLULU, HAWAII The Hawaiian Sugar Planters' Association, an association representing all of Hawaii's 24 sugar-producing companies, wishes to present its views on the proposed cancellation of registration for the herbicide 2,4,5-T. By implication, the fate of other phenolic-derived pesticides, including the important herbicide 2,4-D which is chemically related to 2,4,I-T, is also at stake. 2,4,5-T and 2,4-D have been used widely in Hawaii since about 1948 for control of weeds in sugarcane fields. They are valuable for this purpose and there are no other equally effective herbicides registered by the U.S. Department of Agriculture for use in sugarcane. Cancellation of registration of 2,4,5-T and possibly that of other related pesticides, as originally proposed by Dr. Lee DuBridge, the President's Science Adviser, on October 26, 1969, would cause serious economic hardship to sugarcane growers. A letter explaining our position was sent to Dr. DuBridge on February 5, 1970, and he gave us a very thoughtful, thorough response on March 3. We believe adverse publicity about all pesticides, such as the unconfirmed reports of birth defects in Vietnam attributed to 2,4,5-T, is based largely on emotion and on inadequate scientific investigation. At the same time we recognize and emphasize that massive aircraft treatments of crops, water sources, jungle, and possibly villages in Vietnam differs almost totally from the moderate, controlled agricultural spraying in the U.S. We recognize the possible hazards from poorly controlled pesticides and the need for adequate protection of the public. This is the purpose of the federal regulatory statutes governing pesticides; we believe these laws and regulations are sufficient to insure food crops free of harmful pesticide residues and to protect the public from contact with the chemicals. In support of this statement we quote from Dr. DuBridge's reply to our letter. "Among 5,300 samples of foodstuffs tested for this material by the Food and Drug Administration during the past five years, only two were found to contain more than trace quantities of 2,4,5-T; only 25 contained detectable amounts. Thus occurrence of 2,4,5-T in foodstuffs is indeed rare." Laws of the State of Hawaii permit use of 2,4-D and 2,4,5-T herbicides when applied in such a manner that detectable amounts of spray do not drift to sensitive crops, home gardens, or ornamental plants. Hawaii's semi-tropical climate and year-round conditions favorable for plant growth make the control of all weed species an imperative, constant necessity if crops are to be grown successfully and economically. Application of herbicides, such as 2,4-D and 2,4,5-T, and other pesticides are moderate, as dictated by economic factors and by state and federal laws. Moreover, sugarcane in Hawaii is a two-year crop. Control of weeds by application of herbicides is necessary only in the first few months of growth. Even then the amounts are small and the applications are made with care and precision. Because of these circumstances, no residues of 2,4-D or of 2,4,5-T have ever been found in the harvested crop. In the many years of using 2,4,5-T and related herbicides there have been no known cases of illness or physical defects either in the men who applied them, their families or the public. Neither is there any record of injury or hazard to wildlife or recreation. It now seems probable that the birth defects ascribed to 2,4,5-T in the Bionetics Laboratories study were caused by a contaminant present in the single sample of the herbicide apparently used in the investigation. We understand this fact was pointed out to the Food and Drug Administration by the Dow Chemical Company who had been aware of the contaminant for several years and had modified its manufacturing plant so as to avoid producing it. It is difficult to understand how a carefully controlled scientific study of such importance could be conducted without first determining the purity of the 2,4,5-T used by Bionetics. It is unfortunate that formulated products from several commercial sources were not included as well as highly purified 2,4,5-T. We feel the subsequent publicity given the Bionetics work in the press, in Science magazine, and in the Whiteside article in the New Yorker, was hasty, poorly informed, emotional, and calculated to gain public attention at the sacrifice of scientific verity. We believe the regulatory personnel of the U.S. Department of Agriculture and the Food and Drug Administration acted with discretion and sound judgment, in the face of considerable pressure, to suspend final action against 2,4,5-T until all relevant data were evaluated from other studies to be completed this spring. It is vur mderwanding K as the cut de de rente e se tuerate registratym for 2452 late een eendet die the remainder iĆ 2907ezi extatish whether fers 21 je zmized. Te mort 1 dee derisras and becere mach of the credit for de nice te wende data shout en of the laboratories of Iepw Chemtral Company and vé the Food and Zeug AdminisZTECKE To a bot ver DART 1: THE DESTINOS TOM 1ççünɔn 91 be shown to be dermental to the frid v rom it. the pads DE BLI SO is the unfortomate fiveçuatre für voriete di C kritize - cidrelaties of registradinca of these and trier defu peronde 21 take quare Food-ny and without adequate sorire. It is pencate that jessure fie me vetes is likely to encse, ka tile size wems to late from emicia rather than from carefni consideratise of kofroent woestde eridence. The muero f afirmant weKETT TO VİCKİN TREistration may take many Trare There ja som de andere EDMETE for 2457. One alternative is known and feid testing to it was first term a Bavas a 1953. However, field eralmationA TENGODE BDETHER, and wü- and water-mirement Studies in a two-year ere to provide data to meet regitradion requirements take so mach time that the denial company has not yet been able to file fie registrative of this alternative Composi It is for boge that the intiative of the sfery of 245-7 and of other phenode-derived pesticides w genre by that the results will be carefully and westbally erainted We fear that demares hasd on emotion instead of on fart and reawie rocid depente Americas farmers of essential pesticides. We are conbdent that your committee w provide such reascoed judgment. The following is referred to on p. 376 ABSTRACT Teratogenie Study of 2375 Tetrachloedtemp-dosin in the Rat. G. L Sprain F. L. Dan and V. K. Bowe, The Dow Chemical Company, Midland, Michigan 23.78-Tetrachlorodibenzo-p-dioxin has been found to occur in small amounts as a coctamzitam in some commernally manufacrared samples of 2.4.5-trichlorophenoxy arstie arid. The purpose of this study was to learn whether the presence of this imparity possibly could are not for the feral abnormalities in test animals reported in a recent study poblished data: Blodetics Research Laboratories, Bethesda, Maryland The dioxin was administered by gavage in 9:1 corn oil-acetone solution in doses of 0 Control), 0.03, 0125, 0.5, 20 and 80 mirrograms per kilogram body weight per day to groups of 24 veontrol) and 12 (treatment) pregnant female SpragueDawier derived rats on days 6 through 15 of gestation. On day 20 of gestation, each dam was sacrificed and a cesarean section performed The number of viable and dead fernses and early and late resorptions was recorded. Each fetus was examined for any gross abnormalities. Two-thirds of each litter were fixed in Bouin's solution. Wilson sections were examined under the dissection microscope, and tissues were studied for histopathology. One-third of each litter were fixed in alcohol and examined for skeletal abnormalities by alizarin red-S staining Presented at the meeting of the Society of Toxicology, Atlanta, Georgia, March 17, 1970. No differences were observed in the fetuses taken from dams treated at the dosage of 0.03 ug/kg/day and those taken from dams that received the solvent vehicle only. At the 0.125 g/kg/day dosage, all parameters studies were within normal limits except for a very slight decrease in average weight, and the occurrence of intestinal hemorrhage (18/127) and subcutaneous edema (22/80) in the fetuses from dams that received this treatment. At the 0.5 μg/kg/day level, the number of fetuses was reduced and the number of resorptions and fetal deaths was increased. The average weight of the viable fetuses was very slightly decreased. The incidence of intestinal hemorrhage (36/99) and subcutaneous edema (31/65) was markedly increased over that seen in the 0.125 μg/kg/day treatment. At the 2.0 μg/kg/day level, only 7 viable fetuses were obtained. These were from 4 of the 11 litters examined. Resorptions were numerous, intestinal hemor rhage was frequent (4/7), and subcutaneous edema was present in all of the 4 fetuses examined by Wilson section. One fetus from this treatment level was found to have a kinked tail and two of its feet were somewhat misshapen. Skeletal examination, however, revealed no evidence of bone abnormalities. The 8.0 μg/kg/day dosage level proved to be toxic to the dams. There were no viable fetuses in the dams which were examined on day 20 of gestation. All resorptions occurred early and no evidence of fetal tissue was found. Skeletal examinations revealed delayed ossification of some sternebrae and skull bones. This occurred generally throughout the various groups, including controls, and is not considered to be of practical significance. The results of this study indicate a high level of maternal and fetal toxicity to be associated with 2,3,7,8-tetrachlorodibenzo-p-dioxin. Its presence in the sample tested in the Bionetics Laboratories study could well have accounted for the observations reported and attributed to 2,4,5-trichlorophenoxy acetic acid. о |