7. There was evidence of woody plant mortality from root rot, and also visible damage to certain yard trees from several kinds of insects and woodpeckers or sapsuckers. were observed that appeared to be caused by low soil moisture, air pollution and unusual soil properties. Other plant injuries 8. The phenoxy herbicides following normal use do not usually persist for more than 8 months in soil and water. Additional analyses are in progress to determine the presence or absence of herbicides.' Senator HART. We are adjourned to resume on the 15th of this month in this room. (Whereupon, at 5:15 p.m., the Subcommittee was adjourned, to resume on April 15, 1970.) EFFECTS OF 2,4,5-T ON MAN AND THE ENVIRONMENT WEDNESDAY, APRIL 15, 1970 U.S. SENATE, COMMITTEE ON COMMERCE, SUBCOMMITTEE ON ENERGY, NATURAL RESOURCES AND THE ENVIRONMENT, The Subcommittee met, pursuant to adjournment, at 10 a.m., in room 1318, New Senate Office Building, Hon. Philip A. Hart, presiding. Present: Senators Hart and Baker. Senator HART. The Committee will be in order. Our first and distinguished witness is the Surgon General, Dr. Jesse Steinfeld. STATEMENT OF DR. JESSE STEINFELD, SURGEON GENERAL, DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE: ACCOMPANIED BY DR. DAVID GAYLOR, DR. DIANE COURTNEY, AND DR. DALE LINDSAY Dr. STEINFELD. Thank you, Senator Hart. Accompanying me are Dr. Diane Courtney, on my right, of the Pharmacology and Toxicology Branch of the National Institute of Environmental Health Sciences, Dr. Dale Lindsay, associate commissioner for science (FDA) and Dr. David Gaylor, chief of the Biometry Branch of the National Institute of Environmental Health Sci ences. I have a prepared statement. Senator HART. Yes. I suggest you read it and if there is any footnoting or extension that you want to make as you go along, feel free to do it. Dr. STEINFELD. Thank you, sir. I am pleased to appear before you today to discuss the herbicide known as 2,4,5-T, our efforts to determine its hazard to health, and subsequent action to protect human health. The production of 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) in the United States increased from 8 to 40 million pounds per year in the last decade. In the United States, 2,4,5-T is principally used as a weedkiller in clearing range and pasturelands, roadsides and rightsof-way, in suppressing aquatic weeds, and in eliminating weeds in croplands. It is also used to reduce weeds in turf. The use of 2,4,5-T and its salts and esters on food crops has been registered by the U.S. Department of Agriculture on the basis of no residues in the marketed food. To insure that the foods reaching markets are free of residues, the FDA has monitored the food supply in selected cities. About 5,300 food samples were analyzed for 2.4.5-T and other pesticides in the last 4 years. Residues of 2,4,5-T, at trace levels (less than 0.1 part per million), were found in 25 of these samples. In 1965, one sample contained 0.19 parts per million; in 1966, another sample contained 0.29 parts per million. It is my opinion that the results of the monitoring program justified the registered use of 2.4.5-T on selected. food crops, in the absence of any known toxicity of 2,4,5-T. The development of a balanced public policy which considers benefits and risks associated with the use of a compound such as 2,4,5-T is an exceptionally difficult matter. Great public fear of the possible implications for man has followed reports of harm in laboratory animal tests. And yet frequently it is not known with certainty what laboratory animal tests may mean for man. We are obligated to make decisions of great health and economic importance on the basis of very limited evidence of potential hazard; prudence allows no other course. We are aware that both good and bad consequences may result from our actions. The enormous strides taken in achieving the prosperous and healthy life we now enjoy in an industrial age has created problems and uncertainties which are not easily overcome. The resolution of these uncertainties and solution of these problems will require national commitment and broad public education and understanding. At this point, I would now like to read the joint announcement of Secretaries Hardin, Finch, and Hickel, prepared in accord with the Interagency Agreement for Protection of the Public Health and the Quality of the Environment in Relation to Pesticides. This is the first public release of this announcement. Agriculture Secretary Clifford M. Hardin, Interior Secretary Walter J. Hickel, and HEW Secretary Robert H. Finch today announced the immediate suspension by Agriculture of the registrations of liquid formulations of the weed killer, 2,4,5-T for use around the home and for registered uses on lakes, ponds, and ditch banks. These actions are being taken pursuant to the Interagency Agreement for Protection of the Public Health and the Quality of the Environment in Relation to Pesticides among the three Departments. The three Cabinet Officers also announced that the Department of Agriculture intends to cancel registered uses of non-liquid formulations of 2,4,5-T around the home and on all food crops for human consumption (apples, blueberries, barley, corn, oats, rye, rice and sugar cane) for which it is presently registered. The suspension actions were based on the opinion of the Department of Health, Education and Welfare that contamination resulting from uses of 2,4,5-T around the home and in water areas could constitute a hazard to human health. New information reported to HEW on Monday, April 13, 1970, indicates that 2,4,5-T as well as its contaminant dioxins, may produce abnormal development in unborn animals. Nearly pure 2,4,5-T was reported to cause birth defects when injected at high doses into experimental pregnant mice, but not in rats. No data on humans are available. These actions do not eliminate registered use of 2,4,5-T for control of weeds and brush on range, pasture, forest, rights of way and other non-agricultural land. Users are cautioned that 2,4,5-T should not be used near homes or recreation areas. Registered uses are being reviewed by the three Departments to make certain that they include adequate precautions against grazing treated areas until long enough after treatment by 2,4,5-T so that no contaminated meat or milk results from animals grazing the treated area. While residues of 2,4,5-T in meat and milk are very rare, such residues are illegal and render contaminated products subject to seizure. There is no tolerance for 2,4,5-T on meat, milk or any other feed or food. USDA will issue guidelines for disposal of household products containing 2,4,5-T. The chemical is biologically decomposed in a moist environment. BACKGROUND INFORMATION Secretary Finch's Commission on Pesticides, which reported its findings in November and December 1969, extressed concern that research conducted at Bionetics Research Laboratories, under the direction of the National Cancer Institute, indicated that 2,4,5-T had produced a number of birth defects when fed or injected into certain strains of mice and rats. Because the test material contained substantial concentrations of chemical impurities (dioxins), the birth abnormalities could not be attributed with certainty either to 2,4,5-T, or to the impurities known to be present. Representatives of the chemical industry pointed to evidence of extreme potency of the impurities as toxic agents. They demonstrated that 2,4,5-T now being marketed is of a greater purity than that which had been tested in the Bionetics experiments and urged that further testing be undertaken to clarify the questions raised. Responding to this suggestion and utilizing materials supplied by one of the major producers of 2,4,5-T, scientists at the National Institute of Environmental Health Sciences promptly initiated studies to determine whether 2,4,5-T itself, its impurities or a combination of both had caused the earlier findings, and whether the 2,4,5-T now being marketed produces birth abnormalities in mice and rats. The experiments were completed last week and the statistical analyses performed over the weekend. On Monday and Tuesday of this week the analyses of the data were presented to the regulatory agencies of the Federal Government and to the members of the Cabinet. The dioxin impurities and the 2,4,5-T as it is now manufactured, separately produced birth abnormalities in the experimental mice. Because absolutely pure 2,4,5-T was not available for testing, it is possible only to infer from certain of the observations that the pure 2,4,5-T probably would be found to be teratogenic if it were tested. But, since pure 2,4,5-T is not marketed and could not be produced in commercial quantities, this is not a practical issue for consideration. 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 childbearing years by eliminating liquid formulation of 2,4,5-T use in household, aquatic and recreational areas. Its use on food crops will be cancelled, and its use on range and pastureland will be controlled. Maximum surveillance of water supplies and marketed foods will be maintained as a measure of the effectiveness of these controls. These measures will be announced more specifically in the Federal Register shortly. While the restriction to be imposed upon the use of this herbicide may cause some economic hardship, we must all cooperate to protect human health from potential hazards of 2,4,5-T, other pesticides and the dioxins. The three Secretaries commended the chemical industry for its prompt and willing cooperation with the National Institute of Environmental Health Sciences in the studies to clarify questions raised by the initial studies of this herbicide and for working closely with the FDA in the other studies still underway. They urged the full support of industry, agriculture and the home gardner in insuring the safe use of 2,4,5-T and other pesticides which contribute in important ways to the welfare of the Nation. |