Document Rmb5ErjX6E0qz56bRpnN4pLz

7/?e ^ 'sice* s. 100 The Science and Politics of Cancer Concerns are also mounting on the dangers to the public from "low-level" asbestos contamination of air and water and from asbestos-containing consumer products. As the realization is dawning that asbestos is too ex pensive in terms of disease and death to continue using, the industry is beginning to develop the strategies of re locating in lesser developed countries and promoting the use of fiberglass as an asbestos substitute in the United States. There are serious unresolved questions as to the dangers of fiberglass and there are possibilities that it may be no less hazardous than asbestos. The massive human toll taken by asbestos is probably the single most important incentive to the development of coherent national policies recognizing preventive medicine as a major future component in the delivery of health care. Vinyl Chloride One of the most common pejoratives applied to modem times is "the plastic age." And just as age-old natural materials like wood, glass, and metal have been replaced by cheaper synthetic plastics, this seems to imply, so has the value of our lifestyle been degraded. Many things we now touch or use daily are made of plastic. Yet the plastic transformation of our society has only taken place over the last forty years. The consequences to society of its plastici zation, in terms both of high energy and health costs, have only recently been appreciated. One of the major costs is from cancer.1 Manufacture Plastics are the leading product of the modem petrochem ical industry. This era of plastics dawned in the 1930s with the realization that petroleum was the cheapest and sim- mol can rear six :o the ir and jets. >o exlsing, of reg the nited o the : may hably :nt of itive ry of 30 fl (/> dern tural aced has ; we istic the tici)StS, ajor o <o o ;mnth im- The Workplace 101 plest starting material for the synthesis of the vast array of organic chemicals now used by modem industry. Petro leum then gradually replaced coal, which had been previ ously used for this purpose, and is now almost the exclu sive basis of the organic chemical industry. Vinyl chloride (VC) lies at the heart of the plastics industry. VC was first discovered in 1837. Large-scale production, however, did not start until the 1930s, when it was synthesized from chlorine and ethylene, largely for the manufacture of synthetic rubber.2 Production levels increased rapidly after World War II at a rate of 15 per cent per year, reaching a total of about 7 billion pounds this year. VC is a simple chemical consisting of a small single molecular unit (a monomer) which is normally a gas but can be shipped and stored as a liquid under pressure. VC reacts under conditions of heat and pressure and in the presence of plasticizing chemicals to form large molecular chains (polymers) of polyvinyl chloride (PVC) resins. The polymerization of the VC monomer never proceeds to completion, but always leaves some unreactfed VC en trapped in the PVC resin. Depending on the production process, this unreacted VC has concentrations ranging as high as 8,000 parts per million (ppm).3 This residual VC can be dissolved out of the polymer or released by heating it.4 PVC resins are molded, injected, and extruded in the fabrication of a wide array of plastic products. These in clude phonograph records, wire and cable insulation, floor coverings, garden hose, furniture, upholstery fabrics, car bodies, coating of fabrics and wallpaper, containers, bot tles, and food wrappings. It is difficult to get an accurate count of the number of U.S. workers involved in all the various stages of PVC production. There are about sev enteen VC manufacturing plants, employing about a thousand workers, and forty PVC plants, employing about six thousand workers.5 There are no figures available, 102 The Science and Politics of Cancer however, on the number of fabricating plants or on the number of their employees. These must run into the hun dreds of thousands. Suppression by the Industry of Data on the Carcinogenicity of Vinyl Chloride In May, 1970, an Italian toxicologist, Pierluigi Viola, re ported at an international cancer congress in Houston, Texas, that long-term intermittent exposure of a small group of rats to 3 percent of VC in air (30,000 ppm) re sulted in the production of cancers in a wide range of or gans.6 Prior to this, there had apparently been no studies in the plastics industry on the possible carcinogenicity of VC, although tens of thousands of workers the world over had been exposed to it for over three decades and at least seven fatal cases of liver cancer had occurred in VC/PVC workers prior to 1970.7 Disturbed by Violas public report, a consortium of giant European chemical industries, led by Italy's semi-governmental Montedison, and with con tributions from British, Belgian, and French firms, financed a major study initiated in July, 1971, by Cesare Maltoni of the Bologna Cancer Institute.8 An extensive series of tests were conducted in which adult, infant, and pregnant mice, rats, and hamsters were exposed to VC in inhalation chambers at concentrations ranging from the , relatively low 50 ppm level to the toxic 100,000 ppm (10 $ percent) level. By late 1972, Maltoni had confirmed and extended Violas results. VC was shown to be a potent car cinogen, inducing a rare type of liver cancer (called an giosarcoma) as well as more common liver cancers (hepatomas) and cancers of other organs, including kidney, braihpahd lung. The cancers were subsequently found even at the lowest level tested, 50 ppm.* The overall *At that time the permissible exposure level for U.S, workers was 500 ppm. tumc highc op me socia induj consc it wil dustr detai social infori mont toxic Chen cautit carcir l pleas: of VC * r\ ('o 37 fio 03 Oo) t< CO Nl g ( e tcy same veale NIOS i Amei Mam delib< The Workplace 103 tumor incidence was concentration-dependent, with higher doses increasing the incidence and rate of devel opment of the cancers.9 In October, 1972, the Manufacturing Chemists As sociation, the major trade association of the U.S. chemical industry, entered into an agreement with the European consortium to share their information, but not to disclose it without prior consent.10 In January, 1973, the U.S. in dustry representatives visited Maltoni and were given full details of his studies. The Manufacturing Chemists As sociation (and Maltoni) subsequently failed to disclose this information, in spite of the fact that NIOSH, in the same month, had publicly requested all available data on the toxic effects of VC. In March, 1973, the Manufacturing Chemists Association recommended to NIOSH a pre cautionary label for VC that made no reference to toxic or carcinogenic effects on animals or humans. Also in March, 1973, following complaints of an unpleasant taste, Schenley Distillers found 10-20 ppm levels of VC in their liquors sold in PVC bottles. On the basis of these findings, and still knowing nothing about the carcinogenicity data, FDA then banned the use of these liquor bottles. In December, 1973, the Society of Plastics Industry, the plastics industry trade association, provided the FDA with data on migration of VC from PVC contain ers to food, but made no reference to problems of car cinogenicity. On January 22, 1974, B. F. Goodrich announced that since 1971 three PVC workers in their Louisville, Ken tucky, plant had died of angiosarcoma of the liver. On that same day, the Manufacturing Chemists Association re vealed the by now fifteen-month-old Italian data to NIOSH. According to a recent special committee report of the American Association for Advancement of Science, the Manufacturing Chemists Association "appears to have deliberately deceived NIOSH regarding the true facts. . . . Because of the suppression of these data, tens of . ?3 R&S 106972 104 The Science and Politics of Cancer thousands of workers were exposed without warning, for perhaps some two years, to toxic concentrations of vinyl chloride."11 Distortion by the Industry of Data on the Carcinogenicity of Vinyl Chloride The first published case reports of angiosarcoma of the liver in VC/PVC workers generated an intensive epidem iological investigation of cancer mortality in the industry in several countries. A British Petroleum Corporation study, published in Lancet in 1975, concluded that the longer one forked in a VC plant, the less was the risk of getting cancer.12 Closer examination by NIOSH, however, questioned the interpretation of the English data. Ex pected death rates in workers exposed to VC for fifteen or more years were artificially reduced, and rates in workers with lesser exposures were artificially inflated. Re-analysis of the data by NIOSH, using standard methods, showed a clear excess of mortality from all causes and all cancers, besides angiosarcoma of the liver (Table 5.3). Exaggeration by the Industry of the Costs of Regulating Occupational Exposure to VC As information on the carcinogenicity of VC began to sur face, OSHA was prodded into action. On April 5, 1974, OSHA reduced permissible exposure levels from 500 ppm to a new emergency standard of 50 ppm. Under pressure from labor and independent scientists, who insisted that the new standard was still too high for safety, OSHA then proposed reducing this further to 1 ppm.13 Even at that time, it had been shown that exposure of small numbers of rats to 5 ppm VC induced an increased incidence of cancer, and there was no evidence then (or now) of any safe exposure level for VC, or indeed to any other car cinogen. o CD <o -W4 5.3 ritis! Causf by 1 All caus BP NIOS All canc BP NIOS Digesti' BP NI05 Lung c BP nio: Source: J ity." Lam Val tion valu ppiT and claii Ind' sacl Sne pur star $90 arg The Workplace 105 Table 5.3 Comparison of Causes of Death in VC Workers Reported by British Petroleum (BP) and Recalculated by NIOSH Cause of Death, Reported by BP and Recalculated by NIOSH Standard Mortality Ratios* for Workers Exposed to VC for Varying Times Years of Exposure 9 or less 10- 14 15 or more All causes BP NIOSH All cancers BP NIOSH Digestive system cancer BP NIOSH Lung cancer BP NIOSH 112 107 61 79 137 353 123 58 73 86 76 428 106 47 121 75 62 702 129 101 62 90 133 366 Source: J. K. Wigoner, P. I'. Infante, and R. Saracci, "Vinyl Chloride and Mortal ity.' Lancet 2(1975): 194-195. Values greater than 100 indicate excessive deaths relative to expected popula tion values. ' Nevertheless, industry objected strongly to the X ppm proposal on the grounds that it was both unnecessary and beyond their compliance capability. To bolster these claims, contracts were given out by the Society of Plastics Industries to Arthur D. Little, Inc., of Cambridge, Mas sachusetts. Also, OSHA gave out a contract to Foster D. Snell, a division of Booz, Allen and Hamilton, for the purpose of estimating the economic impact of the new standard. The consulting firms predicted costs as high as $90 billion and losses up to 2.2 million jobs, persuasive arguments in the depressed economic climate of 1974. w-wv 106 The Science and Politics of Cancer However, these estimates were shown by the subsequent experience of the plastics industry to be gross exaggera tions.14 In spite of massive industry lobbying and pres sures, OSHA stood firm on the new 1 ppm standard, which was passed on April I, 1975. Within one year, the VC/PVC manufacturing indus try had successfully met the new standard, and without any major economic dislocation. B. F. Goodrich, one of the industry giants, redesigned its manufacturing technol ogy to enclose VC manufacturing and handling processes and plug possible sources of leaks. Additionally, a "strip ping" process was developed to reduce levels of the un reacted VC monomer in the PVC resin and to decrease VC loss in the process. The initial capital costs of the compliance technology were only $34 million. Contrary to the estimates of the industry consulting firms, B. F. Goodrich found that the new clean-up technology actually cut labor costs and could be profitably leased. (In spite of this, B. F. Goodrich increased the price of its PVC prod ucts in 1976, claiming higher production costs and blam ing these on regulatory standards.) The experience of Union Carbide is similar. In late 1975, an official ex pressed surprise as to how unexpectedly easy it had 7 been for his company to comply with the 1 ppm standard. However, earlier intercompany reports had documented the economic advantages of compliance through recover ing and recycling VC which would have otherwise been discharged into the environment. Estimates of the economic impact of compliance had ignored the major costs to industry from losses of VC gas, with resulting air pollution of the plant and adjacent community. They had also ignored or discounted the major costs to society, both direct and indirect, from failure to regulate, with resulting VC-induced disease. Finally, these estimates did not re flect the emergence of a small and booming industry man ufacturing the monitoring equipment now required to meet OSHA regulations. Cancer and Long before workers, VC mals and t' Studies on Dow Chem induced tox tions as lo' standard.15 were also r Acute dizziness, c noted in V same year, occurrence from VC e. o 'o c _ cr< Iv ci s_ _ _ .d since 197( of unreac is not ye asthma" 1 sale meaf "hot wire plastic fil given off has ascri drochlor The Workplace 107 Cancer and Other Diseases Due to VC Long before the 1974 reports of angiosarcoma in VC/PVC workers, VC was known to be toxic to experimental ani mals and to humans at relatively high concentrations. Studies on experimental animals in the early 1960s, by Dow Chemical Company and others, established that VC induced toxic effects in the liver and kidney at concentra tions as low as 500 ppm, then the U.S. occupational standard.15 At higher levels skin and bone abnormalities were also noted. Acute toxic effects, such as headaches, disorientation, dizziness, drowsiness, and loss of consciousness had been noted in VC/PVC workers as long ago as 1949.16 In the same year, the Russian scientific literature reported the occurrence of chronic gastritis, hepatitis, and skin lesions s from VC exposure. In 1957 there appeared the first report of a new occupational disease among vinyl plastic workers called acroosteolysis, characterized by a thickening or clubbing of the fingers and toes, spasmodic contraction of the blood vessels, painful bone changes, and arthritis of the knuckles. Additional cases of acroosteolysis have since been noted from plastic plants all over the world. By 1966, it was recognized that liver damage, hepatitis and cirrhosis, was common among PVC workers and in sbme cases occurred after only one or two years of employment. Scattered cases of chronic lung disease have been noted since 1970 in workers inhaling PVC dust; any possible role of unreacted VC contained in or absorbed on the dust is not yet known. Also, a characteristic "meat-wrapper asthma" has been noted among supermarket and whole sale meat workers who, in packaging cuts of meat, use a "hot wire" or "cool rod" to cut and seal the sheet of PVC plastic film used.17 In the cutting process, fumes are often given off, particularly by the hot wire. While the industry has ascribed the asthma to common irritants, such as hy drochloric acid, it is not known yet whether there are 108 The Science and Politics of Cancer long-tenn health hazards caused by unreacted VC liber- % t ated from the film. i Since 1974, more than forty deaths from angiosar I coma of the liver have been recorded in VC/PVC plants i in the United States and elsewhere.* More ominously, four i cases have been reported in PVC fabricating plants where / VC exposure levels were under 10 ppm. Cancers at vari h ous other sites, including the brain, lung, and kidney, e have also been found in VC/PVC workers; it should be ti noted that cancers were also induced at these sites in the tt animal tests. While the occupational exposure preceding F the cancers has usually ranged from thirteen to twenty b years, there have been four reports of liver angiosarcoma o following less than six years of human exposure. The true re incidence of VC cancers in exposed workers is still un s> known, because of the long latency periods. However, the at ever-increasing number of reported VC cancer cases in ni organs other than the liver indicates that they can no as longer be considered a rarity.18 sn Despite the growing evidence of chronic human dis ease and the many thousands of workers at risk world in, wide, the industry failed for more than twenty years to tsi undertake any carcinogenicity tests in animals. Such tests em could as easily have detected the carcinogenic effects of pn VC in the 1950s as they eventually did in the 1970s. do There are still elements of the academic community cx, who minimize the risks of VC exposure. A recent bro lr1 chure from the University of Louisville's Vinyl Chloride F*< Project, a multimillion dollar NCI-funded program for the do prevention and detection of VC-induced occupational H cancer and other diseases, states: too to%i The low incidence of cancer development among people du< with prolonged exposure to vinyl chloride is a reflection of the; incj 1 foot * At least seven fatal cases of primary carcinoma of the liver, subsequently diagnosed as angiosarcoma, had been recognized in VC/PVC workers before 1970. Six of these cases occurred in the United States between 1961 and 1963, and the other in Sweden. are stra lion The Workplace 111 VC as a propellant in cosmetic products, including hair sprays. However, the FDA did not consider the matter serious enough to order a recall of VC-containing products so that the public could avoid further exposure. The Health Research Group eventually pried out from the FDA the brand names of hair sprays that used VC as a propellant, identifying Clairol as a top selling product. According to a recent survey by Consumer Product Safety Commission staff, no new consumer products containing VC have been manufactured since 1974, and no VCcontaining products remain on the market in 1978. The FDA also showed reluctance in moving against the use of PVC containers for food products, although it was aware that unreacted VC was leached out of the con tainer walls by the foods or fluids inside. By 1974 the FDA knew that VC levels as high as 9 ppm had been found in vegetable oils sold in rigid PVC containers.25 High levels were also found in other PVC-packaged products, including beverages and cosmetics. While the FDA banned the use of rigid PVC containers for food products and beverages, it did not recall them from the market. The FDA still allows the use of PVC film for wrapping foods. Extensive research is now being done by industry with the object of reducing VC levels in PVC products, especially those intended for food packaging and medical applications.20 However, as indicated in a recent trade journal article, the prospects of success seem slim: At present conventional devolatilizing techniques cannot be successfully offered to PVC. ... It cannot be ex pected, however, that a completely monomer-free PVC resin will be a commercial reality in the near future.27 Summary Vinyl chloride (VC) is a simple gaseous chemical which can be polymerized to form a wealth of plastic materials. Despite recognition for several decades of a wide range of 112 The Science and Politics of Cancer chronic toxic effects in animals and exposed workers, it was not until 1970 that the carcinogenicity of VC was first established experimentally. A consortium of European plastics manufacturers then funded further carcinogenicity testing of VC which confirmed and extended the earlier findings. These results, which were shared with the Man ufacturing Chemists Association, remained unpublished I for over eighteen months until the announcement by B. F. Goodrich in January, 1974, of the occurrence of three t fatal cases of an extremely rare cancer, angiosarcoma of the t liver, among its VC/PVC workers. On the same day, the 1 Manufacturing Chemists Association revealed the results t of the animal tests showing VC to be a potent carcinogen a in rodents, inducing angiosarcoma of the liver and a wide r range of cancers at other sites at exposures of 50 ppm and f below. a In the absence of available information on the car n cinogenicity of VC in animals, its effects in exposed work a: ers were only first recognized because of the occurrence 51 of the three rare angiosarcomas of the liver. Had VC only induced lung cancer, its carcinogenicity would in all II probability have remained unrecognized or ascribed to w n smoking. The present occupational standard of 1 ppm was f d< promulgated by OSHA in spite of estimates by industry of c ar grossly exaggerated costs and unemployment. While the standard affords some degree of protection to workers in VC/PVC plants, it does not protect the greater number of I* dc workers in PVC fabricating plants, nor does it prevent ex rci posures to VC of the public-at-large, particularly those liv toi ing in the vicinity of VC/PVC plants, with attendant risks tO' of cancer and also possibly birth defects. du thi My own company is very conscientious and in< careful about the chemicals we use in the manufacturing process. fro are Rllinptnn M. Beavers. Medical Director and Vice President. Rohm & Haas Company. 107-1. str tioi age