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\tv . . PGB's: Coping With The Although polychlorinated biphenyls realized the public health implications have been used for almost half a cen of the widespread use of this ubiqui tury, It wasn't suspected until a decade tous pollutant with the polysyllabic ago that they may be endangering the name--polychlorinated biphenyls, or public health. Use of PCB's Is declin more simply, PCB's. ing now, and a new law will end their PCB's, a distant relative of the pesti production and distribution-in the cide DDT, are a class of industrial United States in about two years. But chemicals derived from benzene, a FDA will continue keeping a close highly flammable colorless liquid used watch on PCD levels in food, because in motor fuels, detergents, nylon, pesti once this chemical gets into the envi cides, and other products. First synthe ronment it stays there for a long time. sized in Germany in 1881, PCB's were not commercially available until about by Annabel Hecht 1930. Since then, they have been man ufactured in the United States by one It is, as one scientist has put it, an ^firm, Monsanto Company, as well as example of toxicology being unable by companies in Europe and Japan. By to keep pace with technology. For 1970, U.S. production accounted for nearly SO years, a toxic chemical has about half the world output of PCB's. been imposed on our environment, yet The recently enacted Toxic Sub it is only in the last decade that anyone stances Control Act calls for an end to PCD production and distribution in the United States over a two and onehalf-year period. A few days before the law was signed, the Monsanto Company announced that it would stop producing PCB's by October 1977. While this will reduce direct contamination from PCB's in the United Slates it will not bring an in stant or total solution to the problem. Some PCB's from products already in use in the United States undoubtedly will find their way into the environ ment. PCB's from products used in other countries also will get into the environment and over a period of time may "migrate'' to the United States in the atmosphere or ocean currents. Another reason that halting produc tion will not end the problem is that PCB's are virtually indcstructablc. HONS 000773 FDA Consumer / Dee. 1976-tan. 1977 / 2i Lake Ontario fishermen who reel in coho salmon like these can mount them as trophies but have been warned not to eat their catch because of high PCB levels. Employees of the New York State Department of Environmental Conser vation (center) trap fish in the Hudson River for analysis and measurement of u PCB levels. Although now halted, \ discharge of PCB's from industrial plants into the Hudson has created a major environmental problem for 4 New York State. Domestic sales of PCB's now are limited to use in "closed'' electrical systems such as this station transformer (bottom) used by a large power generating company. i They do not decompose in water, acid, or alkalis, and require temperatures up lo 650* C. (1,200* F. for complete destruction). Because they are chemically stable, fire resistant, and do not conduct cicctricity, PCB's have been widely used as insulating fluids in electrical trans formers and capacitors, in heat trans fer systems, and in hydraulic fluids where the ability to resist high tem peratures is required. PCB's also have been used in con sumer goods. They have been used to make plastic more workable and flex ible. They have been put into adhe sives, sealants, caulking, paints and varnishes, insulating tape and protec tive lacquers, lubricants, materials used for waterproofing and fireproofing, fluorescent tight starters, printing inks, carbonless (pressure-sensitive) copy paper, and cutting oil. Outdoors they have turned up in substances used to retard the erosion of soil and to dis solve pesticides. The stability of PCB's may have been a boon to industry, but their persistence has proved to be anything but that to the environment. Each year, millions of pounds of the chemical have been escaping into the environ ment--dumped into rivers and water ways through industrial waste and ac cidental spills, leaked into the soil from trash in dumps and landfills, and carried into (he air from burning of waste and from vapor escaping from paints and coatings. It is estimated that over the past 45 years 1.25 billion pounds of PCB's have been produced (and used in this country. Of this, about 50 million pounds have degraded and 750 million pounds arc still in use. That leaves about 450 million pounds of PCB's in the environment. Although there had been reports in the 1930's of skin eruptions, called chloracnc, and other symptoms as a result of occupational exposure to PCB's, not much thought was given to the possibility (hat the chemical pre sented a threat to the public health until 1966 when a Swedish scientist found PCB's in fish. The fish were first thought to contain the pesticide DDT, which is chemically similar to PCB's. Subsequent findings of PCB's in birds and other wildlife in remote parts of the world showed that contamination of the environment had become global. Then, in 1968, an incident in Japan confirmed that the health of man could be affected by the commercial product. A substantial number of people ate rice oil contaminated with PCB's that had leaked from a heat exchange unit during processing of the oil. Many of those who ate the rice oil developed some adverse reactions, among them severe symptoms of weakness, numb ness of the limbs, dark pigmentation of the skin, swelling of the eyelids, and disturbances in liver function. Babies born to mothers who had eaten (he oil had skin discoloration which disap peared in time. * Fortunately for U.S. citizens, the Food and Drug Administration had started the wheels moving to protect the Nation's food supply from PCB contamination even before the Jap anese misfortune. In 1967, FDA be gan a project to devise a means of separating PCB's from chlorinated pesticides encountered in the analysis of food. In July 1969, FDA labora tories throughout the country were provided instructions for the new an alytical method, and by November 1970, analysis for PCB's was routinely included in both FDA's pesticide sur veillance program and total diet stud ies. Under these programs, samples of fresh fruits and vegetables, dairy prod ucts, shell eggs, grains, fish, animal feeds, and processed foods were ana lyzed for a variety of chemical con taminants. In 1971, the U.S. Department of Agriculture began sample testing of meat and poultry for PCB's and both that department and FDA have kept a close watch for PCB contamination in food during their regular inspection activities. West Virginia was the site of one of the first documented cases of PCB contamination of food in the United States. In July 1969 FDA scientists found PCD's in milk from several dairy farms near Martinsburg. The source of contamination was traced to used transformer fluid that had been used as a base for an herbicide which had been sprayed near the cattle grazing areas. Advised that FDA would not permit interstate shipment of the con taminated milk, State officials halted marketing from the affected farms. Within the next 2 years, seven more incidents of avoidable PCB contamina tion of food were investigated by FDA, the Agriculture Department, and State officials. In one case, chickens had been fed rations containing ground bread cartons and wrappers which tnay have contained PCB's. In another case, heat transfer fluid leaked into fishmeal which, in turn, was fed to poultry and catfish. This was probably the most serious incident of PCB contamination of the food supply and led to recall or seizures of poultry, eggs, fish, and feeds in a 10-State area by FDA and the Agriculture Department. In several other cases, PCB's in paint and sealant used inside silos mi grated into cattle feed and ultimately were detected in milk. This situation occurred again in 1976 when PCB's in two samples of milk were traced to silos coated with PCB-contaminntcd sealant. FDA analysis of food samples dur ing 1969-1971 indicated that PCB levels were relatively low in all foods except fish, milk, cheese, eggs, and by-products used in animal feeds. No PCB's were found in cereal grains and fresh fruits and vegetables. For the most part, PCB's in animal feeds were traceable to isolated industrial acci dents and were not a widespread prob lem. PCB's in milk, however, were caused by their presence in paint or other coatings used in silos and this was a problem of wider magnitude. PCB's were found in fish samples collected throughout the country, how ever, with the highest levels found in fish caught in waters near industrial and metropolitan centers. Early in 1970, FDA established an interim reg ulation--called an "action level"-- forbidding the interstate shipment of any fish that contained more than 5 parts of PCB's per million parts in the edible flesh of fish. The complexity of the PCB problem was only beginning to be realized. In July 19/1 a new source of PCB con tamination was revealed when low level residues of the chemical, found in breakfast cereal samples, were traced to the package the product came in. The manufacturer of the packaging material had used about 95 percent re cycled paper, including carbonless copy paper which contained PCB's. A nationwide survey undertaken by FDA Inter that year showed that 36 percent of food packages sampled had PCB residues ranging up to 338 parts per million and that there was a definite correlation between the presence of MCNS 000775 FDA Contumer / Dec. 1976-Jon. 1977 / 23 The use in silos of painls or sealants containing PCB's has been identified as one of the causes of PCB contami nation of milk. The chemical can migrate into the feed and then turn up In the milk of cows that cat the con taminated food. FDA now prohibits the usi' of paints or other materials containing PCB's in animal feed storage areas. In a number of instances chickens have become contaminated with PCB's by eating feed that contained the chemical. Most of the occurrences of PCB's In animal feeds have been caused by isolated industrial accidents. PCB's in the packaging and the use of recycled paper in the packaging ma terial. To strengthen the Government's ef forts to protect the public from actual or potential harm, a task force was established in September 1971 com posed of representatives of the Federal agencies most concerned, including FDA. The report of the task force, published in May 1972, recommended restrictions on the use of PCB's, rather than an outright ban, based on the belief that such restrictions and better housekeeping during manufacture, use, and disposal of PCB's and products containing them would gradually elim inate these chemicals from the envi ronment. Even as the task force worked, FDA was preparing regulations to set tem porary tolerances for indirect PCB contamination of food, animal feed, and packaging. Taking into account the average daily intake of food that might contain PCB's and the levels of PCB's found in surveillance programs, the Agency set tolerances which would provide an adequate margin of safety for the public and at the same time minimize the economic impact on the food and feed industries. Published in 1973, the temporary tolerances were as follows: 5 ppm (parts per million) in the edible portion of fish and shellfish. 5 ppm in the fat of poultry. 2.5 ppm in the fat of milk and manufactured dairy products. 0.5 ppm in eggs. 0.2 ppm in finished animal feed. 2 ppm in animal feed components of animal origin. 0.2 ppm in infant and junior foods. The regulations also prohibited the use of PCB's in new equipment or ma chinery used by the food, food pack aging, or animal feed industries and in coatings or paints for use in animal feed storage areas. To preclude acci dental PCB contamination, manufac turers of food-packaging materials, human food, and animal feed were re quired to replace heat exchange fluids containing PCB's with fluids that did not contain this chemical. They also were required to eliminate, wherever possible, equipment, machinery, and materials containing PCB's that could contaminate packages, food, or feed. An action level of 10 parts per mil lion was set for PCB's in paper food packaging material except where there is a barrier through which PCB's can not pass between the package and the food. This action level was established pending a public hearing on the issue. Because of FDA's efforts and com- 24 / Pec. 1976-Jan. 1977 / FDA Consumer MONS 000776 pJiancc by the affected industries, there have been no "PCB accidents" involv ing food or feed in interstate com merce since 1972, other than the two silo incidents. Except for fish, the rate of occurrence of PCB's in samples of various types of food analyzed by EDA had dropped to Jess than 1 per cent by 1975. Samples of meat and poultry checked by the Agriculture De partment also showed a significant de cline in PCB occurrence. Fresh water fish remain a problem, though not a major one in terms of the Nation's tola! diet. In 1971, Mon santo Company, sole U.S. producer of PCB's, limited its domestic sales of the product to use in "closed" electrical systems such as hermetically sealed electrical transformers and capacitors. Monsanto's restrictions helped re duce, to some extent, the amount of PCB's entering rivers, lakes, and stroams, but it did not eliminate the PCB's already there. PCB's have a nasty way of accumulating in the flesh of fish (and other animals and hu mans) that cat them. In some instances the PCB levels in Ash have been found to be hundreds of thousands of times higher than the PCB levels of the water in which they were caught. Thus, even a low level of PCB contamination in water can lead to high levels of the chemical in Ash and other aquatic life. This is particularly true of older, larger, oily Ash. While the overall percentage of Ash containing PCB's has declined, the per cent with more than the permissible 5 parts per million has remained about the same. Areas where these high level Ash have been found include the Hud son, Mississippi, and St. Lawrence Rivers, and Lakes Michigan, Ontario, and Onandaga. Coho and chinook salmon, stcelhead trout, striped and smallmouth bass, carp, eel, rock bass, and catAsh are among the species most affected. It should be stressed that these arc fresh water Ash which repre sent a very small part of the national Ash diet, although in some areas fresh water sport Ash arc a significant part of the local diet. The problem is not just a local one, however. Lake Michigan carp have been used to stock private Ashing lakes in Illinois, Ohio, Indiana, and Mis souri. Migratory fish, such as striped bass and shad, spawn in the Hudson, then go out to sea, and Great Lakes salmon, loaded with PCB's, have been seized by FDA inspectors on the West Coast where (hey had been shipped for processing. In February 1976, FDA endorsed a decision by New York State to ban commercial fishing--except for shad-- in the Hudson River and to advise the public not to cat Hudson River fish or salmon from Lake Ontario. Michi gan also has warned the public against eating sports Ash caught in Lake Mich igan. A two-year study, funded by FDA, revealed that people who eat Lake Michigan fish have more PCB's in their blood than people who do not. But no adverse health effect could be identified in the study population. Laboratory studies have shown that commercial PCB mixtures can cause damage to test animals. PCB's affect the reproductive ability of mink and monkeys. Liver damage has been pro duced in chickens, rabbits, quail, and rats. Monkeys fed PCB's developed reproductive problems, liver disease, acne, eye inflammations, weight loss, and loss of hair. Of particular concern is the finding that PCB's produced liver tumors in mice and rats. Except for people who have been exposed to high concentrations of PCB's on the job or who have con sumed large quantities of PCB-con taminated fish, the population at large has had minimal exposure to these chemicals. Still, PCB residues have been found in human fat tissue. It has been estimated that 51 per cent of the population has detectable levels of the chemical in their bodies. Preliminary findings from a national study of insecticides in human milk re vealed that 65 of 67 women were found to have measurable amounts of PCB's in their milk. A group of ex perts in pediatrics and toxicology who studied the findings to date agreed that women should not be advised against nursing their babies. No illness has been reported in the United States, other than from occupational exposure, that can be directly connected with PCB's, although what long range ef fect they will have on human health is yet to be determined. While Congress debated the merits of the Toxic Substances Control Act, efforts were being made on a number of fronts to prevent future pollution from the diehard chemical. The Amer ican National Standards Institute is sued guidelines for industry on the use, disposal, and labeling of PCB's. The Department of the Interior now prohibits the use of PCB's in offshore oil drilling equipment. The Environmental Protection Agency (EPA), which is charged with protecting the Nation's waterways from pollution, has issued regulations to prevent spills of hazardous substances, including PCB's, and has proposed regulations that would prohibit prac tically any discharge into waterways of industrial wastes containing PCB's. These regulations would apply to man ufacturers of PCB's and manufacturers of transformers and capacitors that use PCB's. Earlier this year, EPA recommended carefully controlled incineration as the best method for the disposal of indus trial wastes containing PCB's. A number of Stales have enacted or are considering legislation limiting use of PCB's to closed electrical systems, including Michigan, Minnesota, Indi ana, Wisconsin, Illinois, and New York. An assessment of the effects of PCB's on health has been made by a task force of the U.S. Department of Health, Education, and Welfare made up of representatives from FDA, the National Cancer Institute, Center for Disease Control, National Institute for Occupational Safety and Health, and National Institute for Environmental Health Sciences. In its report, issued in July 1976, the group catted for more research on the chemical com ponents of PCB residues and on the effects of these chemicals on man and animals. Specifically recommended were long-range health studies of peo ple who consume substantia] amounts of fresh water fish which have high levels of PCB's. FDA will conduct an expanded sur veillance program for PCB's in fish and other foods and continues to en courage other Federal and Stale agen cies to step up their efforts to control the entry of PCB's into the environ ment. And although the use of PCB's is declining, their tenacity in clinging to the environment means that all re sponsible agencies will have to devote considerable resources to the control of PCB's for years to come. Annabel Hechl is a staff writer with FDA's Office of Public Affairs. MOMS 000777 FDA Consumer / Dec. /97<W<m. 1977 / 25