The Food and Drug Administration, encered by the possible hazards which this pesticide may timately pose to man, recently has established a maximum tolerance level of the parts per milion for DDT residues in fish products & level, incidentally, which may jeopardize the commercial exploitation of many of the country's freshwater fisheries. The purpose of these hearings therefore will be to develop a better understanding of the nature and scope of the pesticide problem. We hope, in a manner that would be judged balanced and fair, to review both the state of present research into pesticide prociems and the adequacy of existing statutory controls. Today we look forward to hearing from a number of extremely well-informed witnesses. Before doing that, however, let me place in the record two newsletters published by the Conservation Foundation which I think provide an excellent summary of the present pesticide situation, as well as a pro and con discussion of the value of pesticides which appeared in the Washington Post on May 4. (The material referred to follows:) LETTER-A REPORT ON ENVIRONMENTAL ISSUES FROM THE CONSERVATION FOUNDATION, APRIL 25, 1969 POLLUTION BY PESTICIDES SOME NOT VERY WELL CALCULATED RISKS Pesticides, complex chemical compounds, pose a complex dilen.ma. They have cansed incalculable damage to the world's fish and wildlife resources. They are causing serious and subtle changes in the environment. Indeed, they are under suspicion of endangering man himself. Yet man finds them tremendously useful in his struggle for health and survival. For some 25 years, man has been concocting an astonishing assortment of synthetic chemical poisons and spreading them over the planet. In doing so. he has been taking some not very well calculated risks. He has been rebuked and warned for being careless, for not fully understanding the consequences. Some restrictions have been imposed; somewhat greater care is being taken; but man continnes the liberal use of pesticides to wage war on the endless verieties of insects, bacteria, rodents and other small creatures which plague him so relentlessly by attacking him directly, or by devouring much of his precious food and fiber supply. To be sure, the widespread dissemination of pesticides has had extremely tangible benefits which, it is argued, would otherwise have been unattainable. Pesticides are credited with making life comfortable and nuisance-free, indoors and out. They are credited with saving countless lives through the control of malaria, cholera, typhus, Rocky Mountain spotted fever, encephalitis and other diseases. And they are credited with helping man raise and protect an extraordinarily plentiful supply of inexpensive food. The farm and chemical industries point to the crops and livestock saved from destruction, with values measured in the billions of dollars each year. Put another way, it has been estimated that for every dollar invested in protection by pesticides, between $4 and $5 worth of production is saved. (1) But the evidence also shows that, in the headlong rush to rely on expedient chemicals, many mistakes have been made and many safer alternatives have been passed up. There have often been unintended, damaging side effects, including heavy losses of fish and wildlife. Finally, the evidence suggests, at least, that man may be seriously harming himself in the process. Certainly he is taking risks. Dr. Robert L. Rudd, zoologist at the University of California at Davis, warned in a study for CF: "The appearance of new kinds of pesticides and of new and profound effects from those long in use has outpaced the rate at which their effects can be investigated." (2) Says Dr. William A. Niering, Connecticut College botanist: "We are obviously dealing with many biological unknowns in our widespread use of presumably 'safe' insecticides.” (3) How extensive is the use of pesticides? U.S. farmers last year spent an estimated $800 million on them. Total domestic sales this year are forecast at $1.7 billion, most for agriculture, but including $255 million for household and garden use, and another $255 million for industrial and institutional use. (4) The $1.7 billion represents a dramatic increase from the 1965 total of $1 billion. Other indications of increasing use: the percentage of corn acreage treated for insects or disease rose from 1% in 1952 to 33% in 1966; for tobacco crop land the increase was from 47% to at least 81%. (5) In 1966, agricultural aircraft flew a million hours, spraying pesticides over 65 million acres. (6) Many additional millions of acres-roadsides and utility rights-of-way as well as crops― area treated with herbicides to stunt growth or control weeds. There are some 900 basic chemical compounds used to formulate thousands of synthetic commercial pesticides. Classed according to purpose, these include insecticides, herbicides, miticides, fungicides and rodenticides. Most famous-or infamous is the ubiquitous DDT. But there are many others-endrin, dieldrin, aldrin, chlordane, toxaphene, lindane, methoxychlor, heptachlor, parathion, malathion, 2,4-D, 2,4,5-T captan carbaryl warfarin etc. There are chlorinated hydrocarbons (DDT), organic phosphates (malathion), and carbamates (carbaryl). Their properties, effects, dosage and use vary widely. The crucial questions raised by the use of a pesticide are: Is it effective on the target insect? What other organizations does it kill? Is it dangerous to fish, wildlife, man? A pesticide may or may not be highly toxic, or poisonous, on direct contact, to various living things. It may or may not be highly persistent, or resistant to being broken down by nature into harmless components. The insecticide parathion, for example, is extremely toxic. A user who spills some on his skin can expect to die soon afterwards, as has happened to thousands throughout the world. Yet it breaks down quickly in the environment. On the oher hand, DDT is considered only slighly toxic to man; but it may persist for years, with consequences unknown. Some effects of pesticide use Many ill effects of pesticides on marine life and wildlife are well documented; the literature on the subject is voluminous. A sample of the findings: Experiments indicate that DDT in very small concentrations can reduce growth and photosynthesis in certain marine plankton. "Such single-celled algae are the indispensable base of marine food chains," says Dr. Charles F. Wurster, Jr., of State University of New York, Stony Brook. Photosynthesis by marine plankton is estimated to account for more than half of the world's oxygen supply-and some scientists theorize that we are already in an oxygen deficit situation. Wurster says that "interference with this process could have profound, worldwide biological implications." (7) "Marine organisms, especially crustaceans," says Niering, "are extremely sensitive to the persistent pesticides. As little as 0.6 to 6 parts per billion (in the water) will kill or immobilize a shrimp population in two days." (2) The Interior Department's Bureau of Commercial Fisheries says tests show that "oysters stopped feeding and exhibited erratic shell movements when exposed to less than one part per million of many chlorinated hydrocarbons. Shell formation in oysters was inhibited by concentrations of a few parts per billion." (9) Cases in which large numbers of fish have been killed are plentiful. The most celebrated, probably, were the massive kills in the lower Mississippi River from 1960-64. (10) An elaborate investigation traced the cause to endrin, apparently from a chemical plant. (11) Nearly a million small coho salmon were killed recently because of DDT, say Dr. Howard E. Johnson and Charles Pecor of Michigan State University, who deduced that residues were accumulated in the egg yolk of adults, and their fry were poisoned during final absorption of the yolk sac. (12) The widespread loss of robins and other birds-where elm trees are treated with DDT for Dutch elm disease-provides a simple example of "biological magnification," or the unique way in which "hard" or persistent pesticides can be concentrated in more and more potent doses as they move up the food chain. When leaves from a sprayed elm fall, they are eaten by earthworms. The DDT doesn't harm the worms; but it accumulates in their tissues. When robins eat the worms, they accumulate it in ever larger and finally lethal doses. (1) The magnification process also occurs when minute quantities of a pesticide accumulate in tiny marine organisms, and are transferred in ever increasing amounts to plankton-eating fish, carnivorous fish and finally birds of prey. This is possible because pesticides such as DDT are almost totally insoluble in water, but very soluble in fat. So they accumulate and are stored in the fatty tissue of The Food and Drug Administration, concerned by the possible hazards which this pesticide may ultimately pose to man, recently has established a maximum tolerance level of five parts per million for DDT residues in fish products-a level, incidentally, which may jeopardize the commercial exploitation of many of the country's freshwater fisheries. The purpose of these hearings therefore will be to develop a better understanding of the nature and scope of the pesticide problem. We hope, in a manner that would be judged balanced and fair, to review both the state of present research into pesticide problems and the adequacy of existing statutory controls. Today we look forward to hearing from a number of extremely well-informed witnesses. Before doing that, however, let me place in the record two newsletters published by the Conservation Foundation which I think provide an excellent summary of the present pesticide situation, as well as a pro and con discussion of the value of pesticides which appeared in the Washington Post on May 4. (The material referred to follows:) LETTER A REPORT ON ENVIRONMENTAL ISSUES FROM THE CONSERVATION FOUNDATION, APRIL 25, 1969 POLLUTION BY PESTICIDES-SOME NOT VERY WELL CALCULATED RISKS Pesticides, complex chemical compounds, pose a complex dilemma. They have caused incalculable damage to the world's fish and wildlife resources. They are causing serious and subtle changes in the environment. Indeed, they are under suspicion of endangering man himself. Yet man finds them tremendously useful in his struggle for health and survival. For some 25 years, man has been concocting an astonishing assortment of synthetic chemical poisons and spreading them over the planet. In doing so, he has been taking some not very well calculated risks. He has been rebuked and warned for being careless, for not fully understanding the consequences. Some restrictions have been imposed; somewhat greater care is being taken; but man continues the liberal use of pesticides to wage war on the endless verieties of insects, bacteria, rodents and other small creatures which plague him so relentlessly-by attacking him directly, or by devouring much of his precious food and fiber supply. To be sure, the widespread dissemination of pesticides has had extremely tangible benefits which, it is argued, would otherwise have been unattainable. Pesticides are credited with making life comfortable and nuisance-free, indoors and out. They are credited with saving countless lives through the control of malaria, cholera, typhus, Rocky Mountain spotted fever, encephalitis and other diseases. And they are credited with helping man raise and protect an extraordinarily plentiful supply of inexpensive food. The farm and chemical industries point to the crops and livestock saved from destruction, with values measured in the billions of dollars each year. Put another way, it has been estimated that for every dollar invested in protection by pesticides, between $4 and $5 worth of production is saved. (1) But the evidence also shows that, in the headlong rush to rely on expedient chemicals, many mistakes have been made and many safer alternatives have been passed up. There have often been unintended, damaging side effects, including heavy losses of fish and wildlife. Finally, the evidence suggests, at least, that man may be seriously harming himself in the process. Certainly he is taking risks. Dr. Robert L. Rudd, zoologist at the University of California at Davis, warned in a study for CF: "The appearance of new kinds of pesticides and of new and profound effects from those long in use has outpaced the rate at which their effects can be investigated." (2) Says Dr. William A. Niering, Connecticut College botanist: "We are obviously dealing with many biological unknowns in our widespread use of presumably 'safe' insecticides." (3) How extensive is the use of pesticides? U.S. farmers last year spent an estimated $800 million on them. Total domestic sales this year are forecast at $1.7 billion, most for agriculture, but including $255 million for household and garden use, and another $255 million for industrial and institutional use. (4) The $1.7 billion represents a dramatic increase from the 1965 total of $1 billion. Other indications of increasing use: the percentage of corn acreage treated for insects or disease rose from 1% in 1952 to 33% in 1966; for tobacco crop land the increase was from 47% to at least 81%. (5) In 1966, agricultural aircraft flew a million hours, spraying pesticides over 65 million acres. (6) Many additional millions of acres-roadsides and utility rights-of-way as well as crops― area treated with herbicides to stunt growth or control weeds. There are some 900 basic chemical compounds used to formulate thousands of synthetic commercial pesticides. Classed according to purpose, these include insecticides, herbicides, miticides, fungicides and rodenticides. Most famous—or infamous is the ubiquitous DDT. But there are many others-endrin, dieldrin, aldrin, chlordane, toxaphene, lindane, methoxychlor, heptachlor, parathion, malathion, 2,4-D, 2,4,5-T captan carbaryl warfarin etc. There are chlorinated hydrocarbons (DDT), organic phosphates (malathion), and carbamates (carbaryl). Their properties, effects, dosage and use vary widely. The crucial questions raised by the use of a pesticide are: Is it effective on the target insect? What other organizations does it kill? Is it dangerous to fish, wildlife, man? A pesticide may or may not be highly toxic, or poisonous, on direct contact, to various living things. It may or may not be highly persistent, or resistant to being broken down by nature into harmless components. The insecticide parathion, for example, is extremely toxic. A user who spills some on his skin can expect to die soon afterwards, as has happened to thousands throughout the world. Yet it breaks down quickly in the environment. On the oher hand, DDT is considered only slighly toxic to man; but it may persist for years, with consequences unknown. Some effects of pesticide use Many ill effects of pesticides on marine life and wildlife are well documented; the literature on the subject is voluminous. A sample of the findings: Experiments indicate that DDT in very small concentrations can reduce growth and photosynthesis in certain marine plankton. "Such single-celled algae are the indispensable base of marine food chains," says Dr. Charles F. Wurster, Jr., of State University of New York, Stony Brook. Photosynthesis by marine plankton is estimated to account for more than half of the world's oxygen supply-and some scientists theorize that we are already in an oxygen deficit situation. Wurster says that "interference with this process could have profound, worldwide biological implications." (7) "Marine organisms, especially crustaceans," says Niering, "are extremely sensitive to the persistent pesticides. As little as 0.6 to 6 parts per billion (in the water) will kill or immobilize a shrimp population in two days." (2) The Interior Department's Bureau of Commercial Fisheries says tests show that "oysters stopped feeding and exhibited erratic shell movements when exposed to less than one part per million of many chlorinated hydrocarbons. Shell formation in oysters was inhibited by concentrations of a few parts per billion." (9) Cases in which large numbers of fish have been killed are plentiful. The most celebrated, probably, were the massive kills in the lower Mississippi River from 1960-64. (10) An elaborate investigation traced the cause to endrin, apparently from a chemical plant. (11) Nearly a million small coho salmon were killed recently because of DDT, say Dr. Howard E. Johnson and Charles Pecor of Michigan State University, who deduced that residues were accumulated in the egg yolk of adults, and their fry were poisoned during final absorption of the yolk sac. (12) The widespread loss of robins and other birds-where elm trees are treated with DDT for Dutch elm disease-provides a simple example of "biological magnification," or the unique way in which "hard" or persistent pesticides can be concentrated in more and more potent doses as they move up the food chain. When leaves from a sprayed elm fall, they are eaten by earthworms. The DDT doesn't harm the worms; but it accumulates in their tissues. When robins eat the worms, they accumulate it in ever larger and finally lethal doses. (1) The magnification process also occurs when minute quantities of a pesticide accumulate in tiny marine organisms, and are transferred in ever increasing amounts to plankton-eating fish, carnivorous fish and finally birds of prey. This is possible because pesticides such as DDT are almost totally insoluble in water, but very soluble in fat. So they accumulate and are stored in the fatty tissue of birds. When fat reserves are used up rapidly, such as in migration or reproduction, the poisons enter other parts of the system, apparently attacking the nervous system. Says Dr. Ralph A. MacMullan, director of the Michigan Department of Conservation: There is "strong circumstantial evidence" that this sort of magnification is responsible for the alarming decline of many species of birds such as the bald eagle, osprey, peregrine falcon and sparrow hawk. (14) Oddly enough, such birds are not normally poisoned directly by the toxic pesticides. It is now widely believed that reproduction is severely hampered, because residues of pesticide such as DDT are transferred in lethal amounts to embryo birds via the egg yolk, or because the pesticides upset liver enzyme activity and therefore calcium metabolism, resulting in eggshells so thin embryo chicks cannot survive in them. Studies have also indicated that some birds become strangely nervous and aggressive and destroy their own eggs. There have been innumerable cases in which frogs, snakes and birds, as well as wild and domestic animals-have been killed by pesticides, sometimes in massive numbers. Rachel Carson, in her eye-opening best-seller Silent Spring (Houghton Mifflin Co., 1962), cited dozens of instances. Many such kills are due to outright misuse, which of course greatly magnifies the dangers and damage of pesticides. But knowledge, or communication of it to the right people, has not been sufficient to prevent misuse. We do not in fact yet know all the ways in which pesticide applications may be upsetting the balance of nature, though examples from the past are plentiful. We do know that persistent pesticides are carried throughout the world by wind, water and living organisms. Often cited is the fact that even penguins in the Antarctic-so far from any pesticide use-contain residues of DDT. Dr. George M. Woodwell, an ecologist at Brookhaven National Laboratory, speaks of the "serious and subtle changes caused by continuous exposure to low levels of pesticides in the environment . . . that threaten to degrade the biota of the earth and especially the oceans in a very serious way.” (15) The dilemma for man The weight of expert opinion currently holds that humans are not directly harmed by careful use of pesticides. There is apparently no solid evidence of such harm. But practically every human accumulates some pesticides which, as in birds, are stored in body fat. In the U.S. the average is thought to be about 10 to 12 parts per million. (In some countries it is apparently much lower, in some much higher.) Scientists believe that man manages to get rid of pesticide accumulations over a certain level, given a reasonable amount of time. Research on the long-term effects of pesticides on humans is virtually impossible; and it is extremely difficult to extrapolate research on animals to humans. So while there is no convincing evidence that pesticides seriously damage man, neither is there proof that they don't. In fact, there are ominous signs that some long-term surprises lie ahead. Some examples: A number of scientific studies have linked pesticides and other chemical compounds with cancer. They have been thoroughly discussed at congressional hearings. (11) "The total number of pesticides capable of producing cancers in various organs and tissues of man and/or animals is appreciable," Dr. W. C. Hueper, former director of the National Cancer Institute, has said. He also had a comment for an industry scientist who claimed that "there is little likelihood that an epidemic-like occurrence of cancers will result in 10 to 30 years": "He is distinctly whistling in the dark. The facts already on hand do not support such a soothing prophecy." (11) And in early March it was reported that preliminary analysis of a largescale study of 130 such compounds-conducted for the Institute-indicates they are carcinogenic to mice (in very large doses). Pesticides are reportedly among the compounds under suspicion. (16) Other reports suggest that pesticides are a genetic hazard to man, capable of producing mutations, which are usually harmful. Dr. James F. Crow of the University of Wisconsin says "there is reason to fear that some chemicals (including pesticides) may constitute as important a (mutagenic) risk as radiation, possibly a more serious one." (17) Dr. Osny G. Fahmy of the Chester Beatty Research Institute in London says "the amount of pesticide chemicals man is now absorbing from his environment is enough to double the normal mutation rate." (18) He says they are capable of disrupting the DNA molecule; the effects are cumulative; and the mutations may not show up for generations. (3) |