very potent chemical that will destroy poison ivy and poison oak. So there is another balance that one must weigh. Senator HART. But into that formula you have to throw the sort of economic possibility that if this were suspended, if it just wasn't permitted to be marketed for this purpose, and if there is a need for a cure for the ill that this thing treats, maybe there would be a renewed effort to find a third alternative. Dr. STEINFELD. I believe the action which has been taken today will lead to more intensive research to find an alternative to 2,4,5-T to destroy the particular kind of herbs it is capable of destroying. Senator HART. Mr. Bickwit. Mr. BICKWIT. I am sorry to go over the matter of use on food crops again, but I do want to clear this up so that we know precisely what the situation is. It says in the first paragraph of your press release that liquid formulations of the weed killer 2,4,5-T for use around the home, for registered use on lakes, ponds and ditch banks will be suspended. Do you intend to include within that list of uses, the use on food crops? Dr. STEINFIELD. I think that the wording for food crops is otherwise. It would be canceled rather than suspended. Mr. BICKWIT. I am talking about liquid formulation. Dr. STEINFELD. As I read the actions taken, there will be a cancelation of registered use of nonliquid formulations around the home and on all food crops. Mr. BICKWIT. That is clear, but what I want to know is what action is proposed with respect to the use of liquid formulations on food crops. Dr. STEINFELD. My interpretation of this would be-I am not a lawyer but I now see what you are driving at. I think this should have been worded, and we will have to check into it, "liquid and nonliquid formulations around food crops." The intent is not to use the formulation on food crops. Mr. BICKWIT. So the use of liquid and nonliquid formulations on food crops will be canceled? Dr. STEINFELD. I cannot speak for the three Cabinet officers. It is my understanding that the intent is not to permit use on any food crop for human consumption. Mr. BICKWIT. Well, you will permit use on it pending appeals? Dr. LINDSAY. But there is no permitted residue of 2,4,5-T on any food. It would be subject to seizure. Mr. BICKWIT. Now, I would like to deal with your statement that an imminent hazard needs to be present before suspension can take place. Is that to say that there is no imminent hazard from the use of 2,4,5-T on food crops? Dr. STEINFELD. In the studies which have been done, the market basket sampling and the measurement of foods for 2,4,5-T, as I mentioned, it is a very rare instance where these things are found, and in sugar cane the herbicide is probably destroyed in the processing by heat. We do not really know. The action we are taking is based on teratogenicity in mice and the fact that dioxins also cause teratogenicity in rats and perhaps in hamsters. It is a possible hazard. Mr. BICKWIT. Is that what you need to cancel as opposed to suspend-a possible hazard? Dr. STEINFELD. I do not know the law that well. I really do not know the exact wording of the law, do you, Dr. Lindsay? Dr. LINDSAY. No. I am sorry. This is Agriculture's bag, and I do not know it. Senator HART. Let us order printed in the record at the conclusion of your testimony the appropriate sections of the Federal Insecticide Fungicide and Rodenticide Act. Dr. STEINFELD. Fine. Mr. BICKWIT. Have you any information derived from your tests on the degradability of dioxin? Dr. STEINFELD. Dr. Courtney is a pharmacologist. Dr. COURTNEY. We have no information on that. Mr. BICKWIT. In other words, then, it is possible that dioxin is both persistent and accumulative in human beings? Dr. COURTNEY. That is possible. It is also possible that it can be metabolized. Dr. STEINFELD. I would like to volunteer something, that is, that the dioxin which produced the results that we will submit for the record is a very potent teratogen for mice in 10,000 to 30,000 times smaller a dosage than 2,4,5-T as we could obtain to pinpoint which chemicals were the villains. And I think it raises another issue, that is, where else in man's environment could these chemicals be found? We have not shown that these chemicals are teratogenic for man, but we may want to take action. The Food and Drug Administration and Agriculture are presently studying a number of other pesticides in the manufacture of which poly-chlorinated phenols are subjected to heavy temperatures and may produce dioxin. So I think we are having an important study carried out there. Mr. BICKWIT. Are you looking outside the herbicide area as well? Dr. STEINFELD. We must look wherever polychlorinated phenols are subjected to high temperatures. We must look for the presence of dioxin and if we find them we shall have to take appropriate action. Mr. BICKWIT. But the appropriate action is not to find that an imminent hazard exists? Dr. STEINFELD. I do not know what the appropriate action is. I know we are going ahead with this activity. Mr. BICKWIT. I take it you do know what the data are with respect to 2,4,5-T and you do know dioxin is present and you do know it is very potent and yet you have concluded it is not an imminent hazard. If it were you would have suspended rather than canceled use. Dr. STEINFELD. You mean suspended all use everywhere? Is this what you mean? Mr. BICKWIT. Yes. Dr. STEINFELD. I think the question of imminent hazard would relate to pregnant women, but we do not know it is teratogenic for man. Use out in rangelands and forests and so forth, I do not see as a hazard to pregnant women. Mr. BICKWIT. Clearly you have no evidence that it is not. Dr. STEINFELD. No, I have no evidence that it is not, nor that it is, actually. It is a potential. Mr. BICKWIT. And when you have no evidence either way you conclude that it is not an imminent hazard? Dr. STEINFELD. I am tempted to make an analogy, but I probably should not. It is difficult to state that there is no evidence that a number of things are not a hazard to health. I think we are in a never-never land, and where we can, we should try to get as much good hard data as we can and act accordingly. Mr. BICKWIT. Is there any evidence either way on the accumulativeness of dioxin? Dr. STEINFELD. I do not think there is any evidence on dioxin. This is a new area which has opened up which we will have to study intensively. Mr. BICKWIT. Thank you. Senator HART. I am not sure this will come out as an effective analogy, but think for the moment of the general attitude on potmarijuana the prevailing view appears to be that since we cannot be sure it is not harmful, it ought not to be used. Is it not correct now that there is at least disagreement as to whether it is harmful or not? Dr. STEINFELD. I think most physicians, and I am the father of teenagers, feel that pot is harmful. Senator HART. You cannot be sure it is not harmful. Is not that your parental attitude? Dr. STEINFELD. I feel it is harmful because it represents an attempt to escape from reality at a time when children must adjust to the outside world and become independent. So I find it harmful as a crutch which particularly the teenagers and those growing up must not use. Senator HART. Well, you have destroyed my analogy. I was going to pursue it on the assumption that you would agree you cannot be sure it is not harmful. You say you are darn sure it is harmful? Dr. STEINFELD. Yes, as far as teenage use, I think psychologically it is harmful. I do not think we can be sure of enzyme changes or long-term liver effects, this sort of thing. I do not think is is possible to be sure, but I would say it is harmful. Senator HART. What if you were unsure, then would you say let us go ahead, although I am not sure? Or would you say do not use it? You say with respect to the pesticides, you balance it and say since we are not sure it is harmful, go ahead? Dr. STEINFELD. I think we have some evidence in animals that 2,4,5-T is a teratogen and dioxins are present, and while we cannot be certain that women, mankind, behave similary to the mouse, yet pregnant women should not be exposed to this. This is a prudent action. Mr. BICKWIT. Do you know the date on which the National Cancer Institute received the first progress report raising the possible teratogenic nature of 2,4,5-T in mice? Dr. STEINFELD. I have with me a chronology regarding 2,4,5-T. It is a few pages, but it is triple spaced. If you would like I could read it to you. Senator HART. Was that a part of the insert that you presented? Dr. STEINFELD. We can provide it to you, and if you would like I can read it into the record. Mr. BICKWIT. We would like it for the record. Dr. STEINFELD. Maybe it would be useful to go through the chronology. With your permission, I will. Senator HART. Please. Dr. STEINFELD. In presenting the following chronology I should take a moment of the Committee's time to commend Dr. Kotin and Dr. Falk for their foresight and initiative in undertaking the studies which were conducted under their guidance by Bionetics Research Laboratories. This commendation extends also to the scientists in the National Cancer Institute who assumed responsibility for successful completion of the study after Drs. Kotin and Falk transferred to the National Institute of Environmental Health Sciences. It consumed large amounts of their time and energy without assurance that the investment would be rewarded. The total cost of this study approximated $3.5 million, and approximately 20,000 animals were studied. Summer 1963: The National Cancer Institute (National Institutes of Health) awarded a contract to the Bionetics Research Laboratories (Falls Church, Va.) to perform studies of the toxicology, carcinogenicity, teratogenicity, and mutagenicity of pesticides and industrial chemicals which were to be selected by scientists of the National Cancer Institute, according to protocols to be devised by the scientists of the Institute. During the fall, 1963, the chemistry and toxicology of the chemical compounds to be studied were examined and planning of the large-scale carcinogenicity screening operations was initiated. Fall and winter 1964: Large-scale screening activities in carcinogenicity were initiated and plans for teratology studies were drawn up. June 1966: First indication of possible teratogenicity of 2,4,5-T. At a dose of 113 mg/kg of body weight, 2,4,5-T, now recognized as containing substantial concentrations of dioxin impurities, produced an elevated incidence of cystic kidneys in one strain of mice. The 2,4,5-T had been administered by injection. At that point we did not know whether the results produced by injection were significant. The 2,4,5-T had not been fed. November of 1966: 2,4,5-T of a similar grade of purity administered by injection at a dose of 133v./kg. body weight was found to be teratogenic in another strain of mice. The results obtained in June and November 1966, in the absence of information about rates of clearance of injected 2,4,5-T from the blood stream, were regarded as of uncertain significance. This route differs from human exposure and possible differences in metabolism could be very important. January 1968: Oral administration of 2,4,5-T of similar purity was initiated in mice. The data produced in this study indicated teratogenicity (cystic kidneys and cleft palate). May 1968: Oral administration of 2,4,5-T of similar purity at a dose of 113 mg./kg. of body weight produced cleft palate in another strain of mice. September 1968: First draft of the final report of the data on carcinogenicity and teratogenicity was delivered to the National Cancer Institute by the Bionetics Research Laboratories. It should be emphasized that these carcinogenicity data were in an incompletely analyzed state and required scrutiny for possible errors, plus numerous statistical analyses. The first evidence of teratogenicity obtained in rats fed 2,4,5-T was reported. October 24, 1968: The draft report of the "raw" data mentioned immediately above was provided to Dr. Fitzhugh in the Food and Drug Administration. October-November-December 1968: Scrutiny of the carcinogenicity data was undertaken by the National Cancer Institute scientists and report writing begun. January 30, 1969: At a meeting of scientists from the National Institutes of Health with representatives of the regulatory agencies, Consumer Protection and Environmental Health Services, the National Academy of Sciences, and the chemical industry, attended also by Drs. Philippe Shubik and Samuel Epstein, the first two volumes of the final report of data on carcinogenicity, submitted by Bionetics Research Laboratories were made available. In addition a special preliminary report on the teratogenicity of 2,4,5-T, exclusive of data pertaining to the other teratogenicity studies, was provided to all participants in the meeting. The analyses of the carcinogenicity data had been given priority because of its volume and the apparent potential significance, based upon the indications of the raw data. It had been intended to completely analyze the teratogenicity data immediately following completion of the analysis of the carcinogenicity data. At the meeting of January 30 a number of uncertainties in the analyses of the carcinogenesis data were pointed up by Drs. Epstein and Shubik and one of the senior scientists in the National Cancer Institute. On this basis, it was decided to withhold publication of the data and findings until additional animal specimens had been examined and certain features of the study design had been reanalyzed. For the same reason, it was decided that a presentation planned for the March 1969 meeting of the Society of Toxicology would be withdrawn from the program. January-September 1969: Extensive statistical analyses of the teratology data were performed by the National Institute of Environmental Health Sciences. March 1969: In the course of the appropriations hearings, Dr. Endicott promised to provide the results of the carcinogenicity studies to the Congressional Record just as soon as the analyses could be completed. This was accomplished in the last week of April or the first week of May 1969. June 1969: The preliminary report of the carcinogenicity findings was made in the Journal of the National Cancer Institute. June 1969: The Technical Panel on Carcinogenicity for the Secretary's Commission on Pesticides was appointed and included scientists from the National Cancer Institute and the National Institute of Environmental Health Sciences. June 1969: The intent to name a teratology panel to the Secretary's Commission on Pesticides was made known to the National |