Document b08d16L0LJpoO6k27q8z4RvZ

by ELIZABETH N. LAYNE N 1966 A SWEDISH SCIENTIST named Sbren Jenson. Bwdh the Institute (or Analytical Chemistry at the University of Stockholm, detected the man made chemical compounds known as polychlorinated biphenyls (PCBs) in fish taken from different parts ol Sweden, in an eagle found dead in the Stockholm Archipelago, and in the hair of his wife, himsell, and his baby daughter. Neither Jensen nor any other scientist had any idea what quantity of PCDs might be dangerous or possibly even fatal. He knew, however, that the compounds are a chlorinated hydrocarbon closely related to DDT, and that the high concentrations of PC8s in the dead eagle would have been close to a tothal dose if PCS toxicity were similar to that of DDT. Further, an examination of sequence of eagle feathers from the Swedish National Museum of Natural History dating to 1680 revealod fCBs in ono bird collected as far back as 1944. Since Jensen's initial discovery of PCBs in the environ ment. scientists have been dismayed to find the chemical virtually everywhere they have looked for it--tn rainwater in England, mussels in the Netherlands, seals off the coast of Scotland, porpoises n Canada's Bay of Fundy, sea lions in California waters, cod in the Baltic Sea. Adelie penguin eggs in the Antarctic, brown pelican eggs in Panama, osprey eggs on Long Island Sound, river water in Japan, coho salmon in the Great Lakes, tuna oft the Galipogos and Hawaiian Islands, petrels and shearwaters from ihe Pacific Ocean, plankton larout in Ihe North and South Atlantic, polar bears in Arctic Canada, trout in remote lakes in northern Quebec, in the air over cities in the United States, and in human milk samples and human fat. PCBs have joined DDT as a truly global pollutant. But while DDT was deliberately cast mlo the environment, PCBs have leaked their way into the world's ecosystems. We know only sketchily how it has come about. PCBs are not a single compound but a mixture of chemical compounds made up, like DDT. of chlorine, hydrogen, and carbon. They are available in this country--where they have been sold to industry for 40 years--as a colorloss. odorless. u i' /Q7~Z. hONS C71GC4 "ntlBON syrupy liquid or as a resin. The sole manufacturer in the Recent studies in the Netherlands indicate the culprit m Untied Stales. Canada, and Britain is the Monsanto Indus such cases is probably a highly poisonous contaminant, trial Chemicals Company of St. Louis, which markets them chlorinated dibenzofurans. found in some PCBs manufac under the trade name Aroclor. PCBs are also made in France. tured outside the United States, rather than the PCBs Germany. Italy. Japan, and ths* Soviet Union. Like DOT. PCBs themselves. Chlorinated dibenzofurans are "among the are described as insoluble m water, and highly soluble in most poisonous compounds known." says Dr. Robert Rise- oils and fats. They can withstand incredibly high tempera brough. this country's foremost authority on PCBs in wildlife. tures (up to l600aF). and are exceedingly resistant both The presence ot these contaminants explains the high to biological and chemical decomposition. The compounds toxicity of German and French PCBs compared to those are probably at least as stable as DDT and its long-lived manufactured here. breakdown product. DDE. In other words. PCBs have all the Studies thus far indicate that American made PCBs, free necessary characteristics for persistence and accumulation of chlorinated dibenzofurans. have a relatively low aeute within the food chain. toxicMy compared to DDT and to dicldrm. Interestingly The very qualities that make the compounds a threat !o enough, they are not highly toxic lo insects but do have the environment are those that make them of great value a synergistic effect with DDT and dieldrin. It is the shellfish to industry, Since the 1930s PCBs have been used primarily that have been found lo be more sensitive to PCBs than as coolant-insulation fluids in power transformers located other forms of life thus far tested. However, it is perhaps in populated areas, where the danger ot explosion from the significant that all testing in the United Slates and Canada intense heat produced by voltage changeovers presents a is done with PCBs supplied by Monsanto. And an incident special hazard; and in what are called heat transfer systems, in 1963 suggests that at least some past batches of Ameri in which PCBs are circulated through coils or tubes to conduct can-made PCBs may have carried the lethal contaminants. heat from furnaces toovens or radiators. They have long been Professor E.L. McCune at the University of Missouri discov used m those black boxes called capacitors that sit on poles ered his chickens were dying because of PCBs (Aroclor) used and regulate the How ol electricity through transmission lines, as a binder in an epoxy paint that had been freshly applied and m capacitors in fluorescent lights and air conditioners. to parts of their feeding house. The symptoms shown by Theoretically PCBs cannot escape into the environment his chickens are now known to be characteristic of poisoning from these "closed system" uses, but systems can and from chlorinated dibenzofurans. do leak, and insulation lluids degrade and are discarded. To cilc one recent example, a heat transfer system leak in a fish meal plant tast summer made it necessary to destroy UT AS WITH SO MANY environmental pollutants, the 80,000 chickens and a like number of contaminated eggs. possible long term, subiethal effects of PCBs are what It was not until about 1900 that Monsanto encouraged frighten scientists. Three separate lusts m recent months-- the use of polychlorinated biphenyls for a wide variety of with rabbits, with mink, and with ring doves--have all had "open" applications--to prolong hie kill Jile of some pesti- - disturbing results, in the two studies using mammals, the cides. in sealants and synthetic adhesives, in paints, var animals were fed food saturated with American PC9 concen nishes. and wax. in printing inks and carbonless copy paper, trations of 10 to 15 parts per million, a level commonly found in automobile tires and brake linings, and in plasticizers, these days in l ake Michigan coho salmon. (The mink m fact which is presumably why PCBs appear in many consumer were ted on salmon.) The first generations of both mink and plastics. All these new uses accelerated the release of PCBs rabbits faded to produce young The second generation of into the environment through factory waste, abrasion, and ring doves, which had been ted the lowest dose of PCBs, trash incineration. Not long ago the federal Food and Drug produced an extremely high rale of embryonic deaths. In the Administration discovered PCBs in a variety of cardboard light of these results, it is not unreasonable to surmise that boxes used to package dried foods such as cereal. In PCBs pose a considerable long-range hazard (o all animal life. addition, they found PCBs in some samples of shredded The extreme concern among scientists is that there is wheat and noodles packod in those boxes. Carbonless copy no clear evidence that the PCD contaminant, the nighly paper that went into the recycled paper Irom which the poisonous chlorinated dibenzofurans. is not produced Irom cardboard boxes were made is believed to be the source the PCBs after they have entered the environment--or has ot contamination. not been widely present in batches produced in the past In response to mounting evidence of PCO pollution of- that now lie buried in dumps or m lake or river sediments. the environment. Monsanto stopped selling the compounds Dr. Risebrough. who suspects PCBs to be the cause of for those "open" uses last year. And the Department of macabre birth defects and feather loss in young terns in Agriculture has canceled registration lor peMiru)r mixed a nesting colony in Long island Sound, conjectures in a with PCBs. What portion ol tul.il *"*** recent article in Natural History that the contaminants may cd is not known because Motiving- nis nm coni'1 with be the agent causing the delects. Such speculation is such information. However, the company did releaso some 1 prompted by recent experiments with chlorinated dioxins. figuros in November, udder pressure from the scientific cloo chamiest ally ol the chlorinated dibenzofurans. which community and the government, that show production in produced similar birth detects in birds in the laboratory. the U. S. reached a high ol 42.527 tons in 1570. more than Risebrough grimly concludes that "these contaminants double what it had been in 1960. may. someday soon, result in an increase in the numbers How directly lethal to life are PCBs? In Japan in 1968. ot human defects as they work up through the loot! chain more lhan 1,000 people suffered a severe skin acne ' to the ultimate consumer." and liver damage as a result of consuming a commercial'' Until it is known how much polychlorinated biphenyl has rico oil used for cooking. In addition, there were two still been produced and the major sources for release into the births out Of mno pregnancies among the women affected. environment, we will be hindered in efforts to assess or Tho rico oil had been heavily contaminated with PCBs used , reduco the potential hazards. Or. Ian Nisbct of tho joint as a host-transfer fluid in the food processing equipment. scientific stall ot the National Audubon Society and Mas- HONS 0 2 1 0 0 5 JANUARY 1079 sachusctts Audubon, and Dr. Arid Sarofim of MIT, who rend paper on PCBs at a Deccmucr seminar of fhc National Institutes of Health. estimate that about one-half to thrmquarters of all PCBs so far produced have escaped Into the environment. Since dumping by industry must account for a large part ot that quantity. Nisbet and Sarofim guess that a good many PCBs are still in dumps and landfills, whe'-they have not yet come into circulation. Most of the reman' ing loose PCBs. they believe, lie in the shallows of estuaries, bays, and rivers. Here there is a danger they may be released into the food chain, where they pose a special threat to the thousands of aquatic organisms that use these waters as feeding and spawning grounds. It is expected that the PCBs will be released slowly over a period of decades as the sediments in the dumps and in the shallows are turned over and leached out. The highest concentrations ot the chemical so lar found are in the waters in industrial, urban areas. Researchers in Great Britain last year discovered that approximately one ton of PCBs a year it being dumped in the ocean with the siudge from Glasgow sewago treatment plants. A similar amount enters the Irish Sea from Manchester's sewape and the Thames Irom sewage in London. Tests at one outfall m Los Angeles revealed an annual flow ot 10 tons of PCBs. It is hardly surprising to learn that the mam source of PCBs in the human diet is fish, or that a recent report to the Environmental Protec tion Agency noted: "It appears that the most serious chronic PC8 contamination is in fish and fish eating birds. .. which are the terminal carnivores of a complex mesh of food chains in the sea.*' Ospreys nesting in the vicinity ot Long Island Sound have been elevated to the dread distinction of being, 'more contaminated with PC8 than any other wildlife in North America.*' The eggs of the ospreys were found to contain levels three times higher than those that caused massive embryonic deaths in ring dove eggs. Probably relatively few PCBs have so far worked their way down to the coasts. Despite curtailments of production or sales. Nisbet and Sarofim expect that much more will find its way down the rivers, into the estuaries, and out to sea. The situation win inevitably get a tot worse than it is now.M discuss in the hearing. His statements, of course, have been exploited for publicity purposes by the pesticide industry. Dr. Borlaug does not understand the objectives of the environmental scientists he so vehemently attacks. No responsible scientist stands against all pesticides, fertilizers, and other chemicals, as he asserts. Nor have environ mentalists attempted, through anti ODT litigation, to stop the export of DOT to developing nations that cannot afford alter natives for malaria control. by CHARLES F. WURSTER The issue is which pesticides tor which purposes. Excessive dependence on pesticides for insect control, espoused by and ROBERT VAN DEN BOSCH Dr. Borlaug, is an ineffective, costly, and destructive method that is rapidly being replaced by sophisticated and effective integrated control techniques. DDT is incompatible with THE SPECTACLE OF A SCIENTIST, competent in his integrated control because it disrupts the beneficial balance own specialty, being drawn into fields where he has of insect communities, often creates greater pest problems no expertise--and exploited by forces he does not under- -than it solves, ts destructive to wildlife, and is a human stand--is a tragedy of modern science. This occupational health hazard. In short, most of the benefits Dr. Borlaug hazard is particularly acute for some scientists with Nobel . envisions are not attainable with DDT. But they can be Prises. achieved by safer means. Or. Norman E. Borlaug. a plant geneticist, won a Nobel Prise for his work in developing high yield grains. Now, When a broadly toxic insecticide such as DDT is sprayed into the complex machinery of an interrelated insect com however, Dr. Borlaug is enmeshed in controversies where munity, most insects are killed. The field is stripped of its his splendid achievements are of little relevance and his predatory insects and other natural controls, and is thus. expertise is nonexistent or 25 years out-of-date. vulnerable to the rapid resurgence of the plant eating pests. Last October 7th Or. Borlaug testified at DOT cancellation Often this leads to greater pest abundance than before hearings m Washington upon invitation of the U.S. Depart spraying. And the development of pesticide resistant strains ment of Agriculture. Under the rules of evidence, a witness of the pest insects makes matters still worse. The farmer, must qualify as an expert in a subject before he can testify faced with nightmarish insect problems, finds himself ad about it. When the USDA attorney asked Or. Borlaug his dicted to more and heavier insecticide treatments, often at opinion on the effects of DDT on wildlife, the hearing the urging of pesticide salesmen. With rising pesticide bills examiner barred the answer on the ground that Dr. Borlaug was not an expert in that subject. Or. Borlaug testified that and falling crop yields, he is on a treadmill to economic disaster. ' he last studied pesticides in 1944, when he was employed This sequence has occurred in many countries. In two by a pesticide manufacturer. Most of his other testimony regions of Mexico, near Dr. Borlaug's own laboratories, was irrelevant to the issues of the hearing. ` severe insect problems created by insecticides caused aban From that hearing. Or. Borlaug went directly to a press donment of the cotton industry amt collapse of the associat conference arranged by Montrose Chemical Corporation, the ed economies. Excessive pesticide use could destroy the world's largest DDT maker. Without rules of evidence to "green revolution" Dr. Borlaug himself has helped develop; inhibit him at the press conference, and at other forums, he has made unsupportable assertions about DDT and other his advocacy of this discredited approach is poor advice for a starving world. pesticides, wildlife, cancer, insect control, hysterical environ- Entomologists have developed effective, economical, and mentaiists, and other subjects he was not competent to ecologically sound integrated control programs for a number 118 AitrttinOM HONS 0 7 1 0 0 6