Document k9wbRJn1V9nBK5mz7Me7OxjVn

I tI N THE alphabet of environmental contamination, PCBs have a wide variety of uses. Production and I pcb may become as well known as DDT, and for sales figures are not available, but a Monsanto bul some of the same reasons. Like DDT, PCB contains letin lists many products in which pcbs may be used chlorine, hydrogen and carbon; like DDT, it is not as plasticizers, flame retardants, insulating fluids, soluble in water, it is soluble in fat, and it is ex or to impart some other useful quality. Among these tremely persistent in the environment. products are natural and synthetic rubber, electrical I The chemical similarity between the two also sug products, floor tile, printer's ink, coatings for paper gests similar physiological effects in the bodies of and fabric, brake linings, automobile-body sealants, fish, birds, and perhaps people. In one particular paints, varnishes, waxes, asphalt, and many kinds respect which will be discussed later, this has been of adhesives and resins. PCBs are also recommended confirmed in the laboratory. by Monsanto for mixing with chlorinated insecti I A striking difference is that DDT has been used in cides to suppress their vaporization and extend their the open environment with intent, because of its "kill-life." toxic effects, to destroy insects; PCB, although known The amounts being used are suggested by the fact to be toxic, has been used for its other qualities, and that PCBS are available in containers ranging from has escaped into the environment by accident. It is 50-pound cans to 600-pound steel drums and by the not yet known exactly how and where this happens, tank carload. nor how much is escaping. As with many of the chemical compounds s.j Polychlorinated biphenyls, to give pcbs their widely used in this age of synthetics, concern about proper name, are chemical compounds manufactured the hazards of pcbs has been limited to the possible I in this country by the Monsanto Chemical Company exposure of industrial workers. Until 1966 it did not i and in Europe and Japan by other manufacturers. occur to anyone to ask whether pcbs might be re A Monsanto spokesman says that PCBs were first leased into the environment, or if they were, what produced in 1929 by the Swan Corporation which they might do to birds or fish or human beings. later became part of the Monsanto Company, and The first revelation that these compounds had that European production followed, probably about been dispersed in ways which made them avail:, .e ten years later. Aroclor (the Monsanto trade name) to living things came in 1966 with a report bv Sorer. began to be used extensively during World War II. Jensen, a Swedish scientist, that he had ider.ti: o. 16 Environment Vol. 12. No. : DSW 282756 STLCOPCB4064085 By Robert Risebrough with Virginia Brodine pcbs in the bodies of 200 pike (taken from different parts of Sweden), in other fish, and in an eagle. Dr. . Jensen had also analyzed eagle feathers which had been preserved in a museum, some of them going back as far as 1880; he found PCBs first in feathers collected in 1944. A colleague of Dr. Jensen, Gunnar Widmark, re ported later in 1966 to an international commission studying pesticide analysis. One of the problems in isolating and identifying residues of ddt had been the presence of what Dr. Widmark described as "un known but chlorine-containing compounds" so simi lar to ddt that they may sometimes have been mis taken for it. These compounds he and Dr. Jensen had identified as PCBs. The polychlorinated biphe nyls had been found in fish and sea birds, in conifer needles, aiid in some samples of human fat. Scientists in Britain and the Netherlands have now identified PCBs in wildlife of their respective countries. Jensen and his colleagues have recently reported details of their analysis of Swedish wild life. The detection of pcbs in North America began in the spring of 1967 when Monte Kirven of the San Diego Natural History Museum was searching the southwest for peregrine falcons, those swift-flying and now fast-disappearing birds of prey. He found a nest with a single, unhatched, abandoned egg and Januaky-Februaky, 1970 Robert Risebrough, Ph.D., is Associate Specialist at the Institute of Marine Resources, Department of Nutritional Sciences, University of California at Berkeley. brought it to our laboratory at the Institute of Ma rine Resources, University of California in Berkeley. The egg was found to contain five milligrams of DDE, the DDT compound that is apparently the most abundant synthetic pollutant in the environment. The analysis also showed the presence of other com pounds which could not be identified. These same compounds had been evident in the analysis of other species of birds and of fish. Because of the impor tance of the peregrine, an attempt was then made to identify the compounds, but without success until the Swedish papers came to the senior author's at tention. With this clue, further work in his labora tory made it clear that the hitherto unknown com pounds were polychlorinated biphenyls. The Monsanto Company, according to a statement supplied by the company and printed in full on pages 26 and 27, is not yet ready to accept the con clusion that the formerly unknown chlorinated com pounds are indeed pcbs. However, because similar results were obtained independently in the labora tories of Sweden, England, Scotland, the Nether lands, and the United States, supported by detailed descriptions of the analytical techniques used (in - 17 DSW 282757 STLCOPCB4064086 TABLE 1 DDT and PCB in Peregrine Falcone ' Total DDT** PCB Ratio of DDT to PCB Immature bird* California breast muscle (wet)* liver (wet) brain (wet) brain (lipid) carcass (wet) carcass (lipid) Adult bird. California breast muscle (wet) liver (wet) brain (wet) brain (lipid) carcass (wet) carcass (lipid) Immature bird. Arctic breast muscle (wet) breast muscle (dry) liver (wet) brain (wet) body fat (wet) carcass (wet) carcass (lipid) Second year bird. Arctic breast muscle (wet) breast muscle (dry) brain (wet) carcass (wet) carcass (lipid) 14.4 7.7 2.8 36 20.2 300 127 77 49.5 595 85 2,600 2.3 7.8 1.0 0.43 50.3 9.3 63.7 99 296 85 70 5,000 9.4 4-5 1.5 19.3 10.8 160 98 57 34.6 415 65 1.980 0.16 0.54 0.10 0.037 3.2 0.80 5.5 28 84 21 19.7 1,420 1.5 1.7 1.9 1.8 1.9 1.9 1.3 1.4 1.4 1.4 1.3 1.3 14 14 10 12 16 12 12 3.5 3.5 4.7 3.5 3.5 `Concentrations in parts per million -- tret weight, dry weight or lipid (extracted fat) weight "Total DDT includes p,p` DDT, p.p* DDE, p,p' DDD, p,p' DDMU, o.p' DDT and o,p' DDE Adapted from Risebrough et al,, "Polychlorinated Biphenyls in the Global Ecosystem," Nature 220 (5172): 1098, Dec. 14, 1968. eluding mass spectrometry) and the results ob tained, this conclusion is now generally accepted in the scientific community. The amounts found, which the Monsanto statement refers to as "in the parts per million range," have been as large as 1,980 parts pcb per million parts of body fat in North American peregrine falcons and 17,000 parts per million in the fat of the white-tailed eagle in Sweden. The distribution of these compounds is highest in the areas where men are concentrated and carry on industrial activity. They appear in smaller amounts in organisms found at greater distances from urban centers. (See Tables 1 and 2 and the sixth reference under Notes which begins "Jensen. . . .") The Monsanto bulletin previously mentioned re fers to the chemical stability of pcbs and their in solubility in water. These are among the qualities 18 which make them desirable for various industrial uses. They are also among the qualities which make them of great concern as environmental pollutants. Because they have these characteristics, they are extremely persistent -- just how persistent is not known -- and they can be carried, like ddt, far and wide over the globe by air currents, (ddt is one of the most stable and least water-soluble of the chlori nated hydrocarbon pesticides.) The PCBs that have already been found in the environment could not all have come from the one insecticide use mentioned in the Monsanto bulletin. There are four other possible sources, all of which should be explored. The first is the stacks of the plants which manufacture Aroclor and the plants which manufacture the products incorporating AroIclor. The second is other forms of industrial waste. (For example, PCBs, other synthetics, and oil are mixed to make a fire-resistant hydraulic fluid, one of the "closed system" uses of PCBs referred to in the Monsanto statement. Yet the amount of hydraulic fluid that escapes from this "closed system" is sug gested in a Mobil advertisement*stating that "indus try wastes almost four times as much hydraulic oil as it uses." The third possible source is gradual wear and weathering of Aroclor-containing products which may result in slow release of pcbs as vapor or minute particulate matter into the atmosphere; for example, asphalt which may contain pcbs, is sub- Specie* TABLE2 PCB Content oi Eggs of Sea Birds Locality Number ol Samples PBC* Brandt's Cormorant Pelagic Cormorant Murro Pigeon Guillemot Cassin's Auklet Western Gull Black-crowned night heron Caspian Tern Forsters Tern Least Petrel Peregrine Falcon Farallon Islands 17 113 San Mateo County. Calif. 2 62 Farallon Islands 6 558 Farallon Islands San Mateo County 1 20 1 62 Farallon Islands 2 15 Farallon Islands San Mateo County San Francisco County 1 118 1 112 1 480 San Francisco Bay San Francisco Bay 1 330 1 24 San Francisco Bay San Diego Bay 2 805 5 1.010 San Diego Bay 2 114 Baja California Baja California 2 3.; 1 471 Where sample included more than one egg, value given is the average. *In micrograms. Environment Vol. 12, No. l DSW 282758 STLCOPCB4064087 jected to constant friction, and may be a source of either vapor or particulate matter containing FCBs. Fourth, many products containing pcbs eventually wind up in the city dump, where they may be burned. Although fire resistant, at sufficiently high temperatures PCBs may be released as a vapor in the form of highly toxic-fumes. (Oxides of PCBs which would be produced in burning are more toxic than the unoxidized pcbs.) PCBs have not yet been de tected in samples of airborne particulates, but have been shown to be present in rainwater. More study is obviously needed to show the ways in which PCBs enter the environment. Evidence oi Ubiquity The worldwide distribution of ddt and related pesti cides by a variety of mechanisms, but primarily by air currents, is now known (see "Earth, Air, Wa ter," Environment, July-August 1969). Even with out knowing the exact sources of PCBs, it would be Januaky-Febbuaky, 1970 Both ddt ahd pcb affect the hormone systems of birds and rats, and for this reason, may threaten the survival of exposed species such as the least tern shown above with young. possible to discover, by the analysis of various forms of wildlife, whether a similar distribution of pcbs is taking place, or whether PCB contamination is local. In the past two years our own work in California, and that of scientists elsewhere in this country, Brit ain, and Sweden have provided mounting evidence for the worldwide dispersion of PCBS. The levels of PCBs found in wildlife near industrial centers may be very high, frequently higher than the amount of DDT. Birds and fish from more remote areas may contain less PCB than DDT. In Table 1 the concentrations of DDT and PCB found in various tissues in two peregrine falcons from California and two from the Arctic are shown. The final column shows the ratio of DDT to PCB--in the California birds, between one and two times as much DDT; in the arctic birds, from three-and-a-half to six- - 19 DSW 282759 STLCOPCB4064088 teen times as much ddt as PCB. The constrast between the immature and the older birds from both areas is also interesting. The imma ture California bird had 160 parts per million PCB in its carcass lipid (extracted fat), while the adult California bird had 1,980 parts per million. The contrast between the miniature and older migrant birds from the Arctic "was even greater, with an in crease from 5.5 parts per million in the young bird to 1,320 in the older one. The arctic birds migrate through the U.S. and winter in the tropics. Evi dently they pick up both ddt and PCB during their migration and on their wintering grounds. Analyses of Western Gull eggs show that eggs from San Francisco Bay contained more PCB than eggs from the Farallon Islands, 27 miles west of the Golden Gate Bridge, which in turn contained more PCB than eggs from Baja California, a location much further from any industrial center. Samples of bird tissue and eggs from a variety of species were collected off California (see Table 2). Some' of these birds breed in New Zeland and Aus tralia, others on the coasts of British Columbia and Alaska, still others in Alaska and the Canadian Arc tic. It is not clear how much DDT and PCB the birds ingested at their native breeding grounds, and how much in the vicinity of California. What is quite clear is that pcb is widely distributed among marine birds which are at the top of a complex mesh of food chains in the sea. One source of PCBs in the birds is clearly the fish on which they prey, as PCBs have been found in a variety of fish from many different waters. PCBs have also been found in freshwater fish and terrestrial birds, although there is less published data on them than for marine organisms. What is the Hazard? ' The American Conference of Governmental Indus trial Hygienists (acgih) recommends levels of haz ardous materials which should not be exceeded in occupational situations. The ACGIH recommendation for PCB containing 42 percent chlorine is the same as for ddt, namely, a maximum or "threshold limit value" of one milligram per cubic meter of air. (A "threshold" is said to be an amount below which no effect is noted.) But some PCBs are more heavily chlorinated, and for those with 54 percent chlorine, the ACGIH threshold limit value is half as much (0.5 DDT reaches the environment by intent, PCB by accident. The most extensive research on pcbs in wildlife in this country has been undertaken along the California coast, but pcbs have also been found in terrestrial and freshwater organisms. milligram per cubic meter of air). Among the Aro- clors listed for sale by Monsanto are chlorinated biphenyls that are up to 68 percent chlorine and mix tures of chlorinated biphenyls and chlorinated tri phenyls that are up to 65 percent chlorine. The more heavily chlorinated pcbs have been re ported in wildlife both in the U.S. and in Europe, and have been found to be highly persistent in the bodies of fish and birds, while the more lightly chlorinated pcbs are somewhat less persistent, and are metabolized or excreted more rapidly. This was confirmed by a laboratory experiment by Koeman in which Japanese quails were fed a mixture of pcbs. After the birds died, it was found that some of the pcbs, particularly the more lightly chlorinated ones, had been metabolized. However, this is not neces sarily reassuring. Little is known about the metab olites -- the breakdown products -- of pcb; one of the metabolites of DDT (DDE) Affects the reproduc tive systems of birds. - pcbs are described in Dangerous Properties of In dustrial Materials as affecting human skin and li%rer at high concentrations, although how high is not stated. The toxicology is described as follows; The lesion produced in the liver is an acute yel low atrophy. This hepatotoxic action of the chlori nated diphenyls [same as biphenyls] appears to be increased if there is exposure to carbon tetra chloride'at the same time. The higher the chlorine content of the diphenyl compound, the more toxic it is likely to be. Oxides of chlorinated diphenyls are more toxic than the unoxidized materials. The skin lesion is known as chloracne, and con sists of small pimples and dark pigmentation of the exposed areas, initially. Later comedones [blackheads] and pustules develop. In persons who have suffered systemic intoxication the usual signs and symptoms are nausea, vomiting, loss of weight, jaundice, edema and abdominal pain. Where the liver damage has been severe, the pa tient may pass into a coma and die. Cases of occupational chloracne and of systemic damage were reported in the early years of pcb use. Experiments with laboratory animals also revealed the high toxicity of pcbs injected, fed or applied to the skin. There is no evidence to indicate that pcbs in the environment are likely to reach levels which would cause severe injury or death from short-term ex posure. The possible PCB hazard, like so many enivironmental hazards, is one of long-term, low-level i 20 i 282760 Environment Vol. 12. No. l STLCOPCB4064089 exposure and perhaps of effects from its combina cause some thinning of the shells. tion with other poisons. There is also the more in The close similarity of ddt and i'CC suggested ' direct, but no less real danger of destroying other possibility that PCB might have similar physiological forms of life -- part of the vast interconnected web effects. Accordingly, David Peakall of the Langm^i:1 of species of which man is but one part and on which Laboratory at Cornell University, investigated the he depends. effect of pcb on pigeons, and found that, like ddt. The accumulating^evidence that no part of the it induced (stimulated the production of) enzymes world is now free of pesticide residues, the products in the liver, enzymes which broke down estradiol, a of atomic explosions, or of a variety of industrial sex hormone. ?1< pollutants, has induced subtle but profound changes The entire reproductive cycle in birds, from the in our concept of our position in the global ecosys development of the male and female reproductive I tem and in our individual conceptions of remoteness organs to the laying of the egg and the birth of the \ and isolation. There has never been any question chick, is mediated by various sex hormones. When that local ecosystems could be irreversibly changed the work of a hormone has been done, it is broken by the introduction of synthetic chemicals, whether down by enzymes in the liver. However, if the en these introductions be purposeful or incidental. zyme activity is artificially increased by the intro Since the sea, however, is the dominant feature of duction into the body of a chlorinated hydrocarbon, the worldwide ecosystem, interpretations of environ it appears that the hormone will be broken down at mental contamination in terms of local ecosystems, a much faster rate. Among the effects of chlorinated whether terrestrial or aquatic, may be misleading. hydrocarbon pesticides that have been found in birds The accumulation in marine organisms of signifi are delayed laying of eggs, thin egg shells (some cant amounts of several pollutants -- those such as times so thin as to break) and chicks that die at pcbs which are insoluble in water, but soluble in fat hatching. ' -- not only elicits an uncertainty about the long In Peakall's experiment, four groups of four birds term utilization of the sea as a source of human each were used. The first group was given no chlori food, but has suddenly raised the question of the nated hydrocarbon. The second was injected with ultimate survival of a number of species of sea DDE (the persistent breakdown product of ddt) ; 40 birds. These species comprise a very large fraction milligrams of DDE per kilogram of body weight were of the world's wildlife, and doubts about their future injected. The third group was injected with 40 milli would have been considered preposterous and un grams of DDT per kilogram of body weight, and the tenable only three or four years ago. Massive re fourth with 20 milligrams of PCB per kilogram of productive failures have been noted in 1969 in the body weight. The PCB used was Aroclor 1262, which brown pelican in Southern California. The jack is approximately 62 percent chlorine. One, .week mackerel fishery out of Los Angeles has just been laterUthe birds were killed^and. the-portion of the i closed because of the high levels of DDT in the fish. liver containing enzymes was removed. To each liver In terms of the exposure of many forms of life was added a tiny amount of the sex hormone, estra and of people of all ages and states of health to pcbs, diol. The breakdown of the estradiol was increased is there really a "threshold limit value"? Is there two-and-a-half times by DDE, almost three-and-a-half really an amount of polychlorinated biphenyl which times by DDT and five-and-a-half times by PCB^in is safe to breathe or to ingest? No threshold has spite of the fact that only Tralf~as "much pcb was been found for the effect of DDE on eggshell thick used. ness, one of the problems which appears in the re J. C. Street and his co-workers at Utah State Uni productive systems of birds that have ingested the versity investigated the effect of a series of ten pcbs pesticide. Very small amounts of DDE were found to ranging from 21 to 68 percent chlorine on female ~-' y' 'ivp,v I REMINDER' Vs'yv:**:;A*/; - rats. All of them stimulated enzyme induction; the 'i amount of stimulation increased regularly with the percentage of chlorine in the PCB. pcbs containing [ This issue is the January/ more than 60 percent chlorine were as potent in | February issue, one of two . . enzyme induction as DDT. TTri_i&_particularly .inter . esting in view of the_Monsanto statement that "no i.. double issues published during / ; the year (the other will be the . . adverse-effects,r~have been found in rats or otherlaboratory species fed up to 100 parts per milker.. (Street fed rats from 50 to 100 parts per million. 1 i July/August one). The next | Induction of these enzymes would be one of the ex i : magazine you receive will be the j pected effects of the polychlorinated biphenyls in people. Normally the lifetime of the induced enzymes > March issue. 1 is short. The foreign, water-insoluble compounds (continued on page ~ i) 22 i DSW 282761 Environment You 12. NO. 1 STLCOPCB4064090 Little is known as yet about what happens between the manufacture of pcbs and their appearance in the bodiea of birds, fish and people. One possible source of the pcbs in the'environment is manufactured products incorporating pcbs which are eventually thrown away and may be burned, as in the apartment house incinerator shown at right, releasing the compounds or their more toxic oxides into the atmosphere. (continued, from page it) that act as inducers are usually converted to water* soluble derivatives that can be excreted by the kid ney. Enzyme activity falls as the inducers are me tabolized in this way. The polychlorinated biphenyls, however, particularly those with greater amounts of chlorine, are relatively resistant to biological break down. They might therefore persist as inducers without being broken down themselves. As the en zymes are continually induced, hormones and per haps other classes of molecules as well might there fore be metabolized at rates faster than normal over the whole life span of the organism. The long-term significance of this phenomenon is as yet unknown. Investigation of various possible effects of the enzyme activity might be undertaken in workers with a long history of exposure to pcbs. Jamuaiy-Feskuaky, 1970 . Very little data is available about pcbs in people. Both Swedish and British scientists have reported finding them in a few samples of human fat. In North America the profile of the PCB compounds on gas chromatograms of human milk samples was found by Dr. James Enderson and Fred Beland of the Colorado College in Colorado Springs. Although the air of Colorado Springs is much cleaner than the air of our larger cities, it was not evident whether the people of Colorado Springs were obtaining the PCB in their food or were inhaling it. The senior author then measured the PCB in a series of mothers' milk samples from Berkeley and from Los Angeles. Every sample tested contained both pcb and dot compounds. As is well known, the DDT content in mothers' milk is above the maximum concentrations permitted in cow's milk. The Berkeley mothers' milk ' 23 DSW 282762 STLCOPCB4064091 rcB is widely distributed among marine birds which are at the top of a complex mesh of food chains in the sea, including the Leach's petrel shown . here. The accumulation of significant amounts of several pollutants, including pcbs, in marine wildlife, not only elicits an uncertainty about the long-term utilization of the sea as a source of human food, but-has suddenly raised the question of the ultimate survival of a number of species of sea birds. i - -t: - contained about four times the legal tolerance limit. exceed the tolerance or if no tolerance limithas been The Los Angeles mothers' milk had somewhat less set for that particular food. The jack mackerel of DDT, but because of the wide variation within each the Pacific coast and the coho salmon of Lake Michi series, the differences were not significant. The pcb gan, seized and condemned by the Food and Drug concentrations in both series averaged about 0.06 Administration because they contained high levels parts per million of the whole milk. of ddt, contained PCB in addition to the ddt com We can no longer assume 'that the Berkeley air is pounds. cleaner than the air of Los Angeles, and we still do A thorough investigation of the physiological ef not know therefore how much of the PCB in people fects of the agricultural and industrial chlorinated derives from food and how much is absorbed by the hydrocarbons, including their effects on the repro lungs from the air. We did find, however, very small ductive systems of both birds and mammals, is ur amounts of PCB in a sample of cow's milk, and it is gent. We would do well to act on the basis of data present in higher concentrations in fish which are from laboratory animals and wildlife rather than eaten by people. waiting for definitive knowledge from studies of Establishment of tolerance limits of PCB in food is people. Effects on people might not show up for clearly essential. Under present law a manufacturer many years and would be extremely difficult, if not of pesticides must petition for a tolerance limit for impossible, to relate to one specific cause. An effect each pesticide on each food crop treated with the might derive from the interactions of two or sev i particular pesticide. Food shipments contaminated eral pollutants. The white-tailed eagles studied by with pesticides are subject to condemnation if they Jensen in Sweden contained rcB, ddt and mercury compounds. The PCB in birds, fish, and people might derive from only a few of the PCB uses which release a PCBs are available in comparatively large amount of these compounds in to the environment. Release of hydraulic oils con containers ranging from If 50-pound cans to 600-pound taining. PCB into waterways might be one of these. It is also possible that each manufactured product containing PCB, which like all manufactured prod ucts eventually becomes a waste product, will even steel drums, and by the tank tually release PCB into the environment, just as any ddt use will eventually increase the environmental carload. burden of ddt. We very much need therefore to establish the sources of the environmental residues of PCB and to trace the paths by which they move through our environment. If PCB should prove to be 24 Environment Vol. 12. No. 1 DSW 282763 STLCOPCB4064092 Monsanto manufactures Aroclor (trade name for pcbs) at this Sauget, Illinois plant and at a plant in Anniston, Alabama. No data ip available on the loss to the environment of pcbs in the course of the manufacturing process, nor on the losses at other plants where products are manufactured which contain PCBS. Swedish scientists have found pcbs in mussels, plaice, cod, and dogfish from remote parts of the west coast, like that shown at left. 25 DSW 282764 STLCOPCB4064093 an uncontrollable chemical like uut, it will not be possible to speak of "controlled" uses. PCB therefore appears to be another waste product of our technology that is not recycled to primary materials. Although there are unquestionable eco nomic advantages derived from their use, the dimin ishing capacity of our global environment to .-iby,--.', our own wastes should prompt us to consumr whether -- and how -- we can develop a technolngy that can use its waste materials again and again ami that does not permit any persistent wastes with bio logical activity to accumulate. z i 1 J i ii l Monsanto Statement on PCB When this article was in preparation, the Monsanto Company was invited to provide a statement oi its position on PCBs. A series of questions was also ad dressed to the company. The answers to some of these questions have been incorporated into the text of the article. Others follow the Monsanto statement Late in February, 1969, a West Coast newspaper carried a major feature about "a menacing new pol lutant" found in the San Francisco Bay area. The arti cle was based on marine life research carried out by Dr. Robert Risebrough of the University of California. The article stated that residues of pesticides (DDT and DDE) and polychlorinated biphenyl (PCB) were threat ening the welfare of certain birds and posed a long term threat to humans. Monsanto manufactures polychlorinated biphenyl and markets it under our Aroclor trade name. (There are other manufacturers in Europe and Japan.) We, therefore, would like to present some additional facts. The work done by Dr. Risebrough dates back to earlier research by other scientists who, while analyz ing pesticide residues in wildlife, soil and water, en countered unknown or "interfering" substances in the parts-per-million range. Several years ago, two Swedish scientists at Stock holm University's Institution of Analytical Chemistry, Professor Gunnar Widmark and Soren Jensen, reported they had identified these other substances. They said some of the materials were polychlorinated biphenyl or PCB. Since PCBs are not "broadcast" or spread around the land as are pesticides, the scientists the orized that the source must be the industrial wastes of PCB users. In addition to the work of Dr. Risebrough and the Swedish scientists, there have been other studies which indicate the presence of PCBs in the environment. Mon santo is concerned over the situation and is cooperat ing fully with these studies. The common uses of commercial PCB would not nor mally lead to its release into the natural environment. A principal market for PCB is in electrical applica tions where they are used as insulating fluids for transformers and capacitors. In this use, the chemicci is completely sealed in metal containers. Another mar ket is for heat-transfer applications where the PCB fluid functions in a closed system. PCBs are also used in several applications where the chemical is incorporated into a polymer as an in tegral part of the solid material. Such polymers are used in highly specialized applications as an adhesive, elastomer or surface coating. Polychlorinated biphenyls are not sprayed or dusted on crops, woodlands or any other areas, as are pesti cides. To our knowledge, they are not used in tires, house paints, household products, or major vinyl plas tics, as has been charged. Therefore, conclusions cs ;o the source of PCB reportedly found in the environment are difficult to make. It has also been implied that polychlorinated bi phenyls are "highly toxic" chemicals. This is not true. Just like other industrial chemicals and home products now in widespread use, PCBs are not hazardous when properly handled and used. During more than 4C years of U.S. production and use, cases of any toxic effect have been extremely rare -- and then only where the simple precautions recommended for use were not followed. Monsanto has research programs under way to identify the compounds, reported to be PCB, and locate their source. The programs involve precise analysis of environmental samples of water and soil. Also under way are studies to determine the biological effects cf deliberate dosage of PCBs on fish and mammalian animals. Special emphasis is being paid to endocrino logical effects, mineral metabolism and reproduction physiology. Some preliminary biodegradability studies ere under way. Further studies to clearly demonstrate this phe nomenon are contemplated. Very early results of chronic toxicity studies confirm that PCBs are not highly toxic. In 90-day studies on rats and other normal laboratory species, there have been no adverse effects when feedings of up to ICC parts per million were administered. Monsanto has always cooperated on a reaulcr basis with federal, state and university laboratories in their analysis of chlorinated hydrocarbon residues We vr.ii 26 -Environment Vol. 12, No. l DSW 282765 STLCOPCB4064094 - NOTES p. 16. "... but a Montan to bulletin... Technical Bulletin 0/PL-3W. Organic Chemicals Division. Mon santo, St. Louis, Mo., IMS. We are Informed by a Monsanto spokesman that supplies of this bulletin "have been exhausted for several months, and It Is In the process of being revised . . . the old bulletin . . . covers only the plasticiser applications, many of which am only iiirfKcifnd apnlirntiona. To our Amcfor plHallciR.Tg nrn n<l uw*l in all ihn npiiliraiixm sump-nird In tho bulletin. Primary markets nm chlorinated niltUr, tyr*nebutadiene copolymers and polysulfide sealants. Aside from pla. ticizers, the principal market for polychlorinated biphenyls is m electrical applications where the insulating fluids used la trsnsformers nnd capacitntors are completely sealed. In another major market, haat transfer applications, tha fluid Is used in closed systems." "... report by Soren Jensen...." '*Report of a Mew Chemical Hazard," New Scientist 12:612, 1966. p. 17. "... Gunnar Widmark ... human fat." Wldmark, G., "Possible Interference by Chlorinated Biphenyls" in 1 continue to do so. Additionally, Monsanto will continue to exercise the highest degree of control in its manu "Pesticide Residues" Report of the IUFAC Commission on the Development, Improvement, and Standardization of the Methods of Pesticide Residue Analysis, Journal of ths Association of Official Analytical Chemists 50:10(9, No. 5, 19(7. facturing, shipping and storing of PCB -- as we do with all products. In the functional fluids market, we "Scientist* in Britain... Holmes. D.C., J. H. Simmons and J. 0*G Tattoo. "Chlorinated have carried out a program for several years lor the Hydrocarbons In British Wildlife," Nature 216:227, 19(7. Holden. . A. V,, and K. Marsden, Nature 216:1274, 19(7. reclamation of used PCBs to reuse these valuable materials. "... and the Netherlands.., Koeman. J. H., M. C. Ten Noever De Brauw and R. H. De Vos. The source of the marine life residue identified as PCB is not yet known. It will take extensive research "Chlorinated Biphenyls in Fish, Mussels and Birds from the River Rhine and the Netherlands Coastal Area," Nature 221: U2(, March 22. 19(9. . on a worldwide basis, to confirm or deny these initial scientific conclusions. "Jensen and his colleagues . . . Swedish Wildlife." Jensen. S. et al., "DDT in Marine Animals from Swedish Wa ters," Nature 224:247, 19(9. Questions from ENVIRONMENT and answers from MONSANTO. Environment: At which Monsanto plants is Aroclor manufactured? Monsanto: In the United States, Monsanto presently manufactures its Aroclor products at plants located in Sauget, Illinois, and Anniston, Alabama. Environment: Have you monitored emissions at those plants for the presence of PCB? If so, what were the - p. 18. ". . . unknown compounds were polychlorinated bi- phenyls." < Note: Laboratory procedures in this and subsequent analyses for PCBs are described in the papers listed above and in the author's scientific papers. See especially, Risebrough, R. W., P. Reiche. D. B. Peakall, S. G. Herman and M. N. Kirven. "Polychorinated Biphenyls in the Global Ecosystem," Nature 220:1098, 1968. Rise- brough, R. W., P. Reiche and H. S. Olcott. "Current Progress in the Determination of the Polychlorinated Biphenyls," Bulletin of Environmental Contamination and Toxicology 4:192, 1969. ". .. 1,980 PCB ... 17,000 parts per million.. . ." Risebrough, et al., "Polychlorinated Biphenyls in the Global Ecosystora," ep. dt. Jensen, S.. op. dt. results? Monsanto: Extensive efforts are in practice at these plants to prevent PCB losses to the environment. These practices have been in use for many years and con trols are continually being improved. Environment: Does Monstanto itself incorporate PCB into some of its other products? If so, at which plants? Have emissions from these plants been monitored for the presence of PCB? With what results? Monsanto: Controlling practices are also in effect to prevent loss in those manufacturing operations where Aroclor is incorporated into other Monsanto products. Environment Could you tell us what control measures you use to keep the PCB concentrations below the Threshold Limit Value in the plant atmosphere? Monsanto: (No answer) ' Environment We would be pleased to receive any ad ditional information, such as scientific reports, adver tising copy, or any other material you may have on PCB. We would appreciate very much seeing copies of the original work you have done on the toxicity of Aroclors. Monsanto: Our research department summarized some of their work and ... I am making it an enclosure. Editor's not*: The enclosure dealt only with residue analysis, not with toxicity. p. 19. ". . . may be released as a vapor in the form of highly toxic fumes." Sax. N. Irving, Dangerous Properties of Industrial Materials, 2nd Ed., Reinhold Publishing Co., New York. 1968, p. 34. p. 20. "... a complex mesh of food chains in the sea... Risebrough, R. W. "Chlorinated Hydrocarbons In Marine Eco systems" in Chemical Fallout, Morton W. Millar and George C. Berg, editors, Charles C. Thomas, 19(9. "... `threshold limit value' of one milligram...." Sax, N. Irving, ap. dt. p. 84. . "... more lightly chlorinated fobs. ..." Jensen. S. et ml., ep. dt- "... laboratory experiment by Koeman...." Koeman et al., ep. dt. "... laboratory animals ... high toxicity...." Miller, J. W. "Pathologic Changes in Animals Exposed to a Commercial Chlorinated Diphenyl," U.S* Public Health Record 69:1086, 1944. McLaughlin. Joseph. Jr.. Jean-Pierre Marline. M. Jaqueline Verratt, Mary K. Mutchler and O. Garth Fitzhugh. "The Injection of Chemicals into the Yolk Sae of Fertile Eggs prior to Incubation as a Toxicity Teat," Toxicology and Applied Pharmacology 6:7(0. 19(8. p. 22. .. jack mackerel fishery... "DDT Report Halts Fishing." The New York Times. Dec. 7. 19(9. "The breakdown of the estradiol...." ' Results were In average amounts of polar metabolites formed in millimicromoles for each group of four birds: Control -- 29.1 plus or minus (.6: DDE -- 7(.t plus or minus 11.1: DDT -- 93.1 plus or minus 11.2: PCB -- 1(0.0 plus or minus 10.6. `V. C. Street and his co-workers... Street, J. C.. F. M. Urry. D. J. Wngataff and A. D. Blau. "Comparative Effects of Polychlorinated Biphenyls and Orgnnochlorine Pesticides in Induction of Hepatic Microsomal Enzymes." presented at the 166th American Chemical Society national meet ing, New York. Sept. 6-12. 1949. Januaky-Febbuaby, 1970 DSW 282766 STLCOPCB4064095