Document zz0bKjE171aONVMzB9b6Lz4ZR

NOTICE: This material may be protected by copyright tew (Title 17 U. S. Code) An Overview of the!-- Vinyl Chloride Hazard in Canada Introduction While acknowledging direct relationship between in dustrial operations end progress in achieving an improved standard of living, the Science Council has become con cerned about costs that are hidden or ignored,-The Council shares the growing public concern over involuntary ex posure to insidious hazards both within sod outside the workplace. It must be possible to reduce the risks asso ciated with industrial activity whDe stimulating needed industrial growth and innovative activity. The Science Council has an ongoing interest in the rote of science and the scientist in policy formulstion. The effectiveness of communication between scientists and policy fotmulators must be improved. As well, growing controversy over the risks of exposure to such thinp as cyclamates, lead, radiation, mercury, asbestos, points to a need for more communication with the public. What is 1 known, needs to be clesrly expressed and analyzed. What ! b not known or wbat needs to be known, must also be ! dearly stated. In the course of its study on Policies and Poisons, the ; Council win examine six hazards, lead, radiation, asbestos. ' mercury, oxides of nitrogen, and monomer vinyl chloride, ' from medical, technical, legal and regulatory perspectives. ' Seminars on each hazard were held, where the participants | were asked to identify the major issues surrounding esch . hazard. Overviews are being written, compared and analj yzed before the release of a Science Council Report. The Council felt that the six cises selected represented a broad enough spectrum of hazards to enable it to make ' general observations and recommendations on how Canada 1 is coping with man-made hazards of an insidious and ! long-term nature. In particular, vinyl chloride monomer was chosen because it is a typical example of the relatively * new synthetic organic chemicals that are continuously beJ ing introduced into the environment and the market place, j There b no agreement on exactly how many new cbem: icab are being introduced annually. Figures in the literature | range from several hundred to one hundred thousand. For I example, it has been calculated that there are about 2.5 j million chemicals now in the biosphere. Since World War II a very large number of new chemicals have been in Itroduced, but very few have been completely tested for advene effects. Only 3000 have been tested for carcino genesis and 1000 of these have, in fact, been found to be carcinogenic. There are differences between vinyl chloride and the other hazards selected, 1) All the others are industrial waste by-products. The vinyl chloride monomer to which people sre exposed b watted, but it b not a by-product. It is an essential building block in the fabrication of polyvinyl chloride resist. The extent of Hz waste b a measure of tbe in efficiency of tbe industrial process. 2) It appears that dangerous exposure to vinyl chloride monomer b mainly a workplace phenomenon. There b no evidence, as yet, to indicate that people are being exposed to dangerous levels outside the workplace or in consumer products. Tbe other hazards fat the study are not solely occupational. 3) Actions taken to reduce the risk associated with ex posure to vinyl chloride monomer, from the time it ait first publicly recognized as a fatal risk (1973), have been forthright and rapid. Indeed, the cooperative at tack on the problem by industry, labour snd govern ments have led some to label the vinyl chloride ex perience a "success story," since they feel that worker exposure has been reduced to the extent that it b no longer a risk. If indeed tbe vinyl chloride episode has been successful, then there are lessons to be learnt and conclusions to be drawn from this experience that cannot, as yet, be extracted from tbe other hazards under study, where varying degrees of controversy still cxbt Thn Vinyl Chlorldn Problem The Properties of Vinyl Chloride Monomer Vinyl chloride monomer (VCM) b a synthetic organic compound that is quite small and simple in structure. It hat a chemical formula of CHi = CH Q and a molecular weight of 62.5. Vinyl chloride monomer is technically classified at a chlorinated hydrocarbon." VCM b a colourless gas under normal conditions of temperature and pressure, but b usually stored and tran sported as a liquid under its own vapour pressure. VCM was used ss a propellant in pressurized spray containers in the United States until it was banned. Vinyl chloride monomer has a pleasant odour and b practically insoluble in water, but b soluble in alcohol, ether, carbon tetrachloride and fats. This suggests that VCM retained in container materia) can be extracted from or will migrate to substances in the container. Investiga tive work into, the mechanism and rate of transfer b taking piece. VCM, in the vapour phase, is 2.15 times heavier than air. This has implications for tbe dispersion of vinyl chloride monomer in the workplace and in the environ ment Vinyl chloride monomer b explosive within limits of 4-22% by volume in sir. Its flash point temperature b -78*C and it can auto-ignite at 472*C. VCM b photo degradable and will break down into simpler harmless substances when exposed to sunlight. In a 2-day period of exposure a concentration of VCM will diminish by onehalf. Siaclil Uwafci M Sm u>. Arnold, In* CXtaiiali, i4 M. J. rhlSIot,' | Coi'tnHr of Toiooio, >ke ponOt^ technical utd radical Information. 1 Fkao oola that the nuiuaut u campions in Jutiiqr 1X77. "It bv toci rjv*4 thtt ttoe* *toyj chloride monomer it of the ia chemical family at chJorpfom, fonaildrhydJ, carbon tetrachloride, etc* which arc aS know to ha teric to it; ` >-r. vi y! chloride monomer thould km fctea twipeeicd of fcatiof >' s" *ip liver and appropriate ten* tboufc* he** fc"' " tto* -? 24 CHt.v Ucc 047433 k. Under certain conditions of temperature and pressure end in the presence of catalytic agentt, molecules of vinyl chloride monomer can polymerise into very large mole cules by continuously adding to themselves. Substances with this capability are called monomers whSe the end products of the process are polymers. The polymer of vinyl chloride monomer is polyvinyl chloride, a substance easily converted into plastic sheets, films, or more solid mate rial. This capability of polymerisation renders VCM in dustrially usefUL Industrial Background Polyvinyl chloride (PVC) was the first fully synthetic plastic. Jt was first produced in Germany during the 1930s and in 1974, world-wide production exceeded It billion pounds. It bat many uses: -- in rubber-like form (electrical wire insulation and steering), -- is film form (garments, cumins, auto upholstery), -- as rigid shapes (floor tiles, bouse siding, phonograph records), -- as piping (for gas, oil, water pipelines), --- as extruded rigid shapes (window frames, household appliances), -- in foam or expanded form (cushions, fishing floats), -- in latex (impregnated paper, fabric and leather), -- as a copolymer (fa food wrap). Most vinyl chlorids monomer plsnts buDt in-the last five yean have been based on "balanced" oxyehlorinstion technology -- a continuous process using ethylene u the only hydrocarbon feed. In "unbalanced** operations the by-product HO is not utilized. In some operations both ethylene and acetylene are utilized as feed. The system it closed with a substantial portion of it exposed to the out side atmosphere so that leaked VCM is readily dispersed and worker exposure minimized. There are three ma}er steps in processing: Direct chlorination -- Ethylene and chlorine arc re acted to produce ethylene dichloride (EDC). The re action takes place at 70-100*P in a circulating stream of EDC and in the presence of soluble FeClt catalyst. Pyrolysis -- EDC b purified by distillation and ther mally cracked to produce VCM and by-product HCL Conversion is limited to 30-60% per past to minimize by-product and coke formation. Oxycblorinatioa -- Ethylene, HO, and an oxygen source (usually air) are reacted to product EDC This reaction takes place in the vapour phase at 390-500*F in the presence of Cud/CudrKa catalyst on alumina. EDC is recovered from the reactor effluent, neutral ized, wished, and then combined with the EDC pro duced In direct chlorination for purification. HO con version is essentially complete; no excess of ethylene ia usually employed. The reaction b highly exothermic and close temperature control b required to maintain selectivity and prevent catalyst volstizatioo. The oxychlorination process b not in use in Canada. The reaction steps can be represented as follows: Overall conversion efficiencies to VCM of 93-96% no ethylene and 91-92% on chlorine arc reported. Unlike vinyl Chloride manufacture, polymerization of the monomer to polyvinyl chloride resin (PVC) in Canada b a batch process, i-c., the monomer nod other additives' arc charged and reacted in a pressure vessel and then re moved for drying and purification at termination of the reaction. The pressure vessel b opened and cleaned and the entbt cycle b repeated. Seven] polymerization processes and polyvinyl chloride resin types are commercially available throughout the world. However, only two basic types are produced fa Canada -- emulsion and suspension (which accounts for about 95 percent of tbr polyvinyl chloride resin manufac tured fa Canada). In each basic train type a number f resin grades are available, each taQoced to specific end-use applications. The vinyl chloride (possibly wlA a comonomer) fa a rater meduim, with surfactants or emulsifiers and initia tor b polymerized at a specified temperature to produce a resin of a particular molecular weight for a given final application. The reaction b exothermic and good temper ature control b essential. The diverse uses of PVC suggest a wide assortment of processing operations from blending, milling, calendering, coating, extrusion, pelletizing, to moulding. The process ing equipment alto differs widely but for the most part, the basic principles are the same. Typically, the resin b blended with n number of addi tives and processing aids depending on the end product, kneaded under heat and pressure into a molten or plastic Sate, and then formed into the desired or final form.1 More then 90 percent of the vinyl chloride produced in Canada in 1973 was used in the manufacture of PVC The remainder was used in the production of 1,1,1 trichlorocthane.* Production quantities and values of VCM are not avail able in Canada because of the secrecy requirements of the Statistics Act Under this Act, production and export figures are not published because there are leu than four companies involved. The sole producer of vinyl chloride monomer fa Cam ads b Dow Chemical of Canada Limited in Sarnia, Ont ario, with a reported capacity of 200 million pounds per year. This b about 3% of US. production and about 1.25% of world production. Until late 1975 vinyl chloride monomer wu also produced by Gulf OO Canada Limited fa Varcnnci, Quebec. Since termination of the Quebec plant, the balance of monomer required to satisfy the Canadian market has been imported from the united States. Dow Chemical of Canada Iimilcd has announced plana to expand their vinyl chloride monomer manufac turing facility by 197t with, a 700-oiifiion-pound per year plant in Fort Saskatchewan, Alberta. There are nine major monomer producers fa the US. with 14 plants and a total capacity approaching 7 bDlioh pounds per year. Chlorination: C,H, - a,-------CiHA Pyrolysis: . . C,Ha.---- - C,H,a - Ha Oxychlorination: CH - 2HQ - Q,------ CtH,Cli - HtO 2CiH. - a- o-... - 2C.w.rTho Tabic I shows polyvinyl chloride resin manufacture in Canada. A third producer, Monsanto Canada Limited, with * reported annual capacity of 40 million pounds, ter minated polyvinyl chlo. de production at their LuaUe, Quebec plant toward tb* end of 1975. CHEMISTRY IN CA1..J-.*. UCC 047434 2 TABLE1 Canadian Pve Unix P*oouen* Euo Chemical Canada......................................................... BS. Goodrich Canada Ltd..................................................... B.F. Goodrich Canada Ltd.................................................... Rant Location Sarnia. Ontario Niagara FaUxOnb Shawwigan, Quabae Rant Capodty - MOlion Lbs. SO 73 >0 , Projected PVC Roductte Figures far 1979 3B0 3TO 80 Source A/nold, 1976 p, 4* Note: Far comparative purposes, polyvinyl chloride resta mpsdty fa the Unitad States b reported at 6.5 Union annual pounds with approximately tO piants. World-wide, ratin production an an annual oasis in 1974 was reported at 18.4 Ullien pounds. ' < TABLES Production op Fvc Ream Year 1974.................................... 1973.................................... .................................... 1971.................................... ..................................... 1971.................................... .................................... 1970.................................... 1969.................................... AVERAGE. PVC Resin Quantity Oba) 247,968.519 217,402,886 171471,471 % Increase Produnion from Previous Year 104 1L4 104 10.7 104 105 Total Amount of Synthetic Resins Quantity Oba) 946,990,600 1,043,616,000 921,694,000 733400,000 657.931,000 555,855400 Note: 1975 figures not availabla. They an confidential to meet secrecy requirements of the Statistics Act. Source: Statistics Canada, Sp*tifi*4 Chtmitth, Information Canada, Ottawa, December, 1972, cat. no. 46-002, p4. * %PCV Synthetics 27 24 24 23 24 26 24.7 1J ? 1 i i t TABLES iNTWntOVtNCtAL AND FOREIGN SHIPMENTS OP PVC, 1969 Destination of Shipments Quebec............. Ontario............ Exporta............ Survey Totab.. Estimated Dollar Value % of Total % of Total 6000 Shipments Production 7.094 354 544 74 0.03 96.1 0.4 Kota: Origins of shipments arc confidential to meet secrecy requirements of Statistics Acl _, Some*: Statistics Canida, InlttprctintM ana routtn Skip- mtnU / SiUcttd Chtmical rrtductt 196$, cat. no. 31-517, June 1*71, p. 1. .Polyvinyl chloride production capacity in Canada win be Increased in 1979. B. F. Goodrich Canada United an nounced expansion plans for their existing Niagara Falls plant and Diamond Shamrock has announced plant to erset a new plant in Fort Saskatchewan.* The Shawinigan plant of B. F. Goodrich was bu3t in 1942 and it the largest producer of polyvinyl chloride resio from vinyl chloride monomer gas. The plant had pre viously been owned by several other companies which were almost totally U.S. owned. This it also the case with ether large chemical products companies In Canada. Polyvinyl chloride resin production accounts for 25 per cent of all synthetic resins produced in Canada (Tablt 2). Considering that thest resins arc then fabricated into thousands of end-products, polyvinyl chloride contributes substantially to the Cansdiao economy. It it alto a rapidly growing industry which h increasing production by 'OJ per cent each year. Although the Statistics Canada survey of Interprovincial and Foreign Shipments b for only 1 year, it indicstm the proportion of PVC resins being shipped as exports. Since 1969, the number of products has decreased in Quebec and presumably the proportion of PVC resins shipped to Ontario hat decreased. Using the estimated value of pro duction for 1969 and the value of exports of FVC resins, exports arc less than 0.03 per cent of PVC production in Canada. (Table 3). Table 4 shows the approximate number of workers em- Stayed in Canada in the overall vinyl industry. Workers i this instance refers to men and women engaged in pro cess and fabrication operations, maintenance, technical, and supervisory roles.* The number of workers in the U.S. employed in the vinyl industry (VCM and PVC manufacture and fabrica tion) b approximately 600,00V The production of vinyl chloride monomer and poly vinyl chloride does not contribute substantially to Cana dian employment (550 people directly employed and 1425 office workers). Employment in the fabrication of FVC end-produeta b difficult to estimate because of the variety of products and the number of small companies utilizing it The Plastic Industry Council cstimstes thst there are 50,000 workers in related plastic fabricstion plants in Csnsdt genersting an annual incorot of about $500,000,- ooa Canada's production satisfies about 70 per cent of ha own demand for PVC resins. The amount of FVC resins exported i significant in a supply-demand profile. The t-c* thst Wr import 30 per cent of the FVC resins required ir.jir . for eor.,5"ued growth within Canada. (Tsbls > C3 26 ANADA, SUMMER 1977 ucc 047435 e Canada imports PVC rums, films and sheets |))' dustries to the area, including polyvinyl chloride pipe and from moral countries. Tbc US. supplies on overage of wire and cable insulation. Feedstocks for the new operation I0.S per ecot of the mins and 72.5 per eent of the das wOl ha purchased from Dow Chemical Canada, which will end sheets. Other major suppliers ere West Germany. ha producing vinyl chloride monomer from ethylene to Japan, Sweden, Italy, France end Spain (about 20 per cent he made by Alberta Gas Ethylene at Rad Dear, AMa of the imports). In 1975, total PVC imports valued $31.- Building of e 1-2-biIlioo-lb ethylene unit will start aeon".* 111,000. This is 0.1 per cent of Canada's total imports Polyvinyl chloride production b likely to continue to from all sectors or M per cent of all imports of inedible grow by 10.5 per cent each year. The establishment of a fabricated materials. new plant in Alberta wd increase tbb annual growth wdb- The 400-mflHon-lb/year polyvinyl chloride plan stsntially. By 1979 the production of PVC resins will ha planned by Diamond Shamrock, a subsidiary of Diamond about 3$o per cent greater than in 1974 if the rata of in Shamrock Canada Ltd. and Alberta Gas Trunk Line Co. crease in production and demand remains the same for the lid., win cost about $50 million. First stage of the project, next five years as h has for the last 5 years and if the capable of turning out 220 million-lb/yesr of polyvinyl Alberta plant produces its estimated 220-mfilioo lb ca chloride, should be onstream in first-quarter 1979. The pacity of PVC. This b an increase which cannot ba ignored. partners wd set up s joint venture to operate the plant, It will have a large impact on tbc Canadian economy since slated to be built near Fort Saskatchewan. Aha. Tht Unit this increase in production should cause a multiplier effect is expected to attract polyvinyl chloride fabricating in in tbc fabrication sector. TABLE 4 Cmaxactuistics or Coufanos Fmducing VCM and PVC Companies Involved Vinyl CUaridt .V/oiwnt Dow Chcmial................................... Gulf Oil (until 1972).......................... PrfniitW CUeridt B. F. dooikh Chemical................... Imperial Oil (Exxonl......................... Monsanto (until 1975)....................... Gulf On (until 1972).......................... TOTAL EMPLOYMENT Locaiioo Sends. OuL YarcanawQuL Shavinina. Qua. Niagara Fall* Sarnia, OnL Villa LasaDe Varennet, Que. % Forties Controlling Ownership Country 100.00 71.10 Bi 100.00 9040 99.40 71.10 VS. Si Employment Plant Office 90 250 210 160 47 82 29 100 1,100 410 200 -- 950 1.426 Source: Statistics Canada, Initr^etpataU Oimtuhip 1S71. Information Canada. November 1974, cat. no. 61-513; Scott's, (fritter In* dmltial Diuctarr 1ST3-74, 6th edition. Penstock Publications Limited; Scott's, IndMhial Diutiety af Oniaria Afanufaelurm, lOth edi tion, Penstock Publications Ltd.. June 1976. TABLES Consumption or Pot.rvj.vn. Chlokide Rhins in Canada Year 1974............ 1973............ 1972............ 1971............ 1970............ AVERAGE. Quantity Produced (lb) 251405.215 247.968.919 217,402ASS 171.871.471 160.360.209 Percentage of Total Consumption Produced fe Canada 616 715 674 694 744 70.7 Quantity Imported Ob) 111176.900 93.933.000 103,305.800 73.892.600 63470.700 Source: Statistics Canada, Specified Cktmicah, 1972 through 1975, at no 46-002. Percentage of Total Consumption Imported 31.4 274 324 30.1 211 294 Total Consumption (lb) 366.992.000 341.902.000 320.709.000 245.761.000 214.231.000 CHFVmTItY IN CANADA. SUMMER 1977 uco 047436 27 Medical Problem* Associated with bpnri>l* Vinyl CM rid* Monomer Vinyl cMorkle earn* M world mentloo as m beattb hazard in December 1973 when throe instances of rare form of Hver cancer, angiosarcoma, were reported in worker* from the B. F. Goodrich plant la Louisville, Kentucky. These case* attracted attention because of the rarity of this particular type of cancer. If carcinoma of the tun* or colon bed developed in these workers, the connection be* tween vinyl chloride end cancer would probably etOl be unrecognized. In addition to the carcinogenic effects of vinyl chloride, there are other toxicological effects. Mon of the informs* lion available conies either from studies of industrial work* era or from animal experiments. Emphasis must be placed on the human studies, but for a proper perspective and understanding of the problem, we must include and study data from experimental animal work.. When large scale production of polyvinyl chloride starred in the late 1930s, vinyl chloride was considered one of the safest industrial chemicals. Aside from two. reports of acute vinyl chloride intoxication, without se rious consequences, there were no indications of an occu* pational health hazard with this chlorinated hydrocarbon. In 1949 Tribukh el el reported hepatitis without jaundice, hypotension, anemia, chronic gastritis, skin and respiratory lesions in 73 workers in a Soviet plastics factory. The ' findings were attributed to plasticizers.' Suciu, in Romania, remarked with reference to this as late as 1963, that tran sient toxic inflammation of the liver must have been con cerned. These observations made in the Soviet Union and Romania remained unnoticed in the West because tbc data were inaccessible. As late as 1968. Schottek, in a | lecture held in Leipzig, concluded that liver and kidney damage was caused by chronic exposure to vinyl chloride. j In the meantime, injury to the health of cleaners of I polymerization reactors was reported in the West in the ! mid-sixties. Opinion on the innocuousness of vinyl chlo ride get changed. Injuries to health manifested themselves | in many different ways, l.e., as bandlike bone effects on ! the terminal ossicles of the fingers (scroosteolysis), as * Mood flow disturbances in the hands, and as **pins-and1 needles" and abnormal sensitivity to cold (Raynaud's syn drome). In addition, pliic-iike hardening of the connective tissue, mainly of the forearms (scleroderma) was de tected. The findings were published in 1966 and interpreted as manifestations of occupationally-induced disease.* Despite these reports it was the general conclusion that the processing of polyvinyl chloride was not a serious hcslth hazard. Many standard textbooks, even up to 1972, em phasized the harmlcseness of processing PVC This was probably due to the results of animal studies that had takes place prior to 1970. Toxicological studies of vinyl chloride monomer dste back to 1930 when Fatty observed the acute toxicity of massive dosages of vinyl chloride in guinea pigs. When exposed to 3-716 and to 2.516 vinyl chloride, these ani mals lived I hour and 8 hours respectively; however, no alterations were,noted after a 1-hour exposure to IJ% nor to 1-hour exposure to 0.35* vinyl chloride. A number of studies since have dealt with acute poisoning by massive exposure to high dosages of vinyl chloride. These are only relevant to the vinyl chloride problem in relation to pos sible industrial accidents. They show the narcotic effects of vinyl chloride where death it preceded by convulsions, .accelerated respiration followed by respiratory failure, congestion of all the vbetra, central nervous system de- \ pretskm and hyperemia of liver and kidneys." Until recently, very few (chronic) studies on the toxicity . resulting from repeated exposure to vinyl chloride mono mcr have been carried out In 1938, Scbaumann found no liver or kidney damage in mice and rats that were lightly anaesthetized for 4 hours daily on 3 to S consecutive day* and 1 hour daily for 4 weeks. Dogs anaesthetized far 3 hour* with 10 per cent by volume also showed no Over and kidney injury but higher concentrations (20 per cent by volume) caused marked salivation, respiratory arrest and vomiting." In tbe early 1960s, Torkelson, Oven and Roam exposed rabbits, rats, guinea pip and dop to levels ci 300, 200. 100 and 50 ppm (1280, 512^56, and 128 mg/ m*) of vinyl chloride for periods up to 7 hours/d*y, 5 days/week, for up to 6 months. At 300 ppm (1280 mg/ m'l, rats showed increased liver weight and pathology. At 200 ppm (312 mg/m*) and 100 ppm (256 mg/m*) rats showed an increase in liver weight but no pathology. Rab bits exposed to 200 ppm (512 rnf/m*) also revealed liver pathology. No chanps were noted in dop or guinea pip at this level. All spades tolerated 50 ppm (128 rag/m*) for 6 months without effect. Repeated exposure for 1 hour/day at 200 ppm (312 mg/m') or 100 ppm (256 mg/ m1) were tolerated in all species without effect." These studies comprised until recently all the signifi cant animal toxicity data. On the basis of the animal data and the fact that vinyl chloride had been used as an anaes thetic at concentrations of 7-10 per cent by volume, then was a general consensus among toxicologists' that vinyl chloride possessed low toxicity. The principal industrial hazard was hs flammability." In 1975 Frodan er ef described chronic toxic effects after exposure of guinea pip to 10 per cent vinyl chloride lor 2 hours daily for varying periods of up to three months. Marked growth disturbances were noted and severe lesions were noted in the liver, spleen, kidney** and lungs." The U.S. Center for Disease Control conducted an epidemiological study for birth defects in the vicinity of vinyl chloride monomer plants and discovered 53 in the period 1970-73 as against the 31 statistically expected. The National Institute of Occupational Safety and Health had previously reported an excess of defects, still births and miscarriages la three cities having vinyl chlo ride monomer pleats." Viols er ef. Observed (1970) that vinyl chloride pro duced tumours in rats. After exposure of 26 rats to 30,000 ppm vinyl chloride 4 hr* daily, 5 days/week for 10-12 months. Viola observed 17 skin tumours,-7 pulmonary tumours, which wer* mainly carcinomas and 5 osteo chondromas. Maltoni and Lafemine who reviewed Viola's results interpreted the lung tumours as predominantly metaitase* from the skin cancers which arose from the gland of Zymbal (a sebaceous gland of the exterior acoustie duct). Maltoni and Lafemine embarked on an extensive study using mainly inhalation but also endopcritoncal in jection. subcutaneous injection, ingestion and transpla cental routes of vinyl chloride administration. The results of Meltonf* studies were impressive. He showed that vinyl chloride produced tumours in the three species studied -- rats, mice and hamsters. A wide range of tumours was produced including Zymbal gland carcinomas, nephro- blssiomas, angiomas and angiosarcomas of the liver and other sites, trichoepiih-liome- ' , lung adenomas, mammary ade ,1 nri lymphomas. ? CHh.MIVi;; * ................ SUMMER 1977 ucc 047437 There wu some variation b tb range of induced tumoun from species to species. Liver angiosarcomas were observed b all three animal species, lo the liver, blood vessel acta* sits, endothelial hyperplasia with or without cellular atypia and fibroblastie changes frequently occurred, ta addi tion to angiosarcomas. Fibroangioblastic proliferation was also often observed b the spleen. MaltonTs studies showed a definite dose-response relationship as far as angiosarco ma and nephroblastoma were concerned. Dosages as low as 50 ppm have been associated with hepatic angiosar coma. He demonstrated two subcutaneous angiosarcomas b tha offspring of breedbg animals exposed lo vinyl chloride for 7 days during pregnancy, indicating the likeli hood of a transplacental effect of vinyl chloride." Part of MaltonTs data (1974) is summarised in Table f, It is not surprising that studies of human toxicity from exposure to vbyl chloride monomer are not as extensive as animal studies. Ideslly epidemiological studies should lead to dose-response curves correlating exposure data and tumour (or other responses) incidence. Because of the extremely high concentrations of VCM in plants with little or no reliable monitoring facilities, beesuse of the turnover of personnel and lack of complete medical records, and because of unknown effects of ambient con centrations of other chemicals used b the process, which could tlso co-promote carcinogenesis, H is impossible to determine the shape of the human dose-response curves except b a roughly qualitative manner. In workers exposed to an environment with a high concentrattion of vinyl chloride, symptoms begin almost immediately. After the first few breaths, there is a pleasant taste b the mouth, followed by euphoria. Dizzi ness, headaches, somnolence or complete narcosis com monly follow. Somnolence often persists long after the worker leaves the factory. The sleep is deep, dreamless, commonly lasting 9-14 hours; one worker slept for 3 days intermittently. This nsreolizing effect led to consideration of vinyl chloride as an anaesthetic at one time. Vinyl chlo ride is detectable in air by ft* odour in concentrations of 1100 ppm. Acute exposure to 4000 ppm for five minutes or more leeds to dizziness and confusion. Higher concen trations may lead to unconsciousness and death. Vinyl chloride monomer fell into disfavour as an anaesthetic be cause of the narrow range between the anaesthetic dose and the fatal dose. Two deaths from accidental acuta vinyl chloride poisoning have been reported. Cyanosis, local burns, congestion of lungs and kidneys and failure of the blood to clot were noted. ' After repeated or chronic exposure, the main neurolo gical symptoms art headaches, irritability, dizziness, sleep disorders, diaphoresis, memory loss, general asthenia and parasthesia. Skin sensations of formication and beat were noted as well as dyspeptic symptoms, epigastric pain and anroexia. Hepatomegaly with hepatic fibrosis, splenomegaly j hepatitis, ulcers, Raynaud's syndrome, allergic dermatitis j scleroderma, acroosteolytis, thromSoeytopcnia, restrictive | pulmonary disease with'lung fibn tii of linear type and j emphysema on chest x-rays and de' matological conditions, j especially contact dermatitis have jeen recorded. Lahorej lory findings reported include BSP retention, increased | urinary excretion of monochioroacctic acid, an increase b peroxidase, indophenoloxidssc and glutathione, increase j in blood catalase, serum albumin, cholinesterase, and : pseudocholinesteresc. Thera is a correlation between the | symptomatology and the degree of exposure to vinyl chloride. Mott of the severe clinical manifestations were found b workers who cleaned reactors. In ooe study by Suciu at of. a comparison was made of workers b 2 fac tories before and after the introduction of a 22-fold re duction of VC in the air. AH the clinical manifestations of VC toxicity were greatly reduced (approximately by twothirds) following the introduction of these measures." In factory workers both VC tod PVC cause a sensitiza tion dermatitis which has been attributed to the plasticiz ers used. It is noteworthy that outside the factory, various reactions have also been observed. In consumers, hyper sensitivity has been reported with PVC products contain ing epoxy resin pUstidzers-stabnizen. In children, VC and dibutylphthalatc release from floor eovcrinp have caused an eczematous dermatitis. In bfants and adults, irritation of the eyes and respiratory tract hat been ascribed to libera tion of volatile materials from polyvinyl chloride floor tiles. It has also been shewn that the plasticizer, Di-2ethylhexyt phthalata can migrate bto stored blood and hence bto tissues from polyvinyl chloride Mood bags. The toxicological implications of this are n t known. Acroosteolysii deserves special comment because ft was the first well-recognized toxic effect of vinyl chloride. The unusual disorder is a dissolution of the bones t the ter mini! phalanges of one or several fingers, and & accom panied by clubbbg, swelling and sbonenbg f tha ter minal phalanges and nail beds. The condition was asso ciated with hand cleaning of polymerization reactors, al though there is some evidence to suggest that it is not just a local disease. Rapid diagnosis to prevent progression f vbyl chloride induced scleroderma, Raynaud's syndrome and acroosteolysis is essential Measures introduced in cluded reduction b exposure of vinyl chloride b the air, water wash, gloves, a yearly physical examination, X-ray of the hands and periodic thrombocyte counts because thrombocytopenia occurred much earlier than any tber sign." The first liver angiostroma cases in polyvinyl chloride workers were reported by Creech and Johnson b the United States b 1974. Angiosarcoma is a rare form of cancer and is not uniquely associated with vinyl chloride. Although at first disputed, the identification of vinyl chloride as a carcinogen in human beinp has now been convincingly established. As of Match 1976, there are 4t known cases of VCrclsted hepatic angiosarcomas in the world; 45 are dead and 3 are still alive. They arc distributed as follows: Can ada 10, United States 17 (14 dead, 3 still living); Germany 9, France 3, Italy 2, U.K. 2, Sweden 2, Czechoslovakia 2. Yugoslavia 2 and Norway 1. All but one were workers handling large quantities of liquefied vinyl chloride under TABLE 6 Extaacr not MaltonTs Data, 1974 -- Exposure to Vbyl Chloride Number of Animals Exposed Number Developing Uvw Angiosarcoma 6000 ppm 2300 ppm 500 ppm 250 ppm SO ppm 72 74 67 67 64 11 9 7 2 0* `Subsequently, hepatic angiosarcoma wat found b this group. Studies are now in progress with 23.10 and 5 ppm) Source: Phillips,1976, p. 1* rupMtcTBv ik ravana cM\t\tp irt pressure; the exception tt as accountant. Forty-six of the 41 worker* in PVC polymerization plants bad worked directly ob the, polymerization process and, for long pe riods, they cleaned reactors where vinyl chloride exposure would have been at Its highest Nine of the Canadian cases worked In one plant Qn Shswiaigaa, Qua.), and 9 of the VS. cases wonted in n siogle plant (Louisville, Ky.l. These were old plants, but then are other plants in West ern Europe and the UJf. (approximately 20), with equally leog histories, with no known easts. The aget of tha 4g vinyl chloride workers at the tint angiosarcoma was diagnosed ranged from 31 to 71 yean with a mean age at diagnosis of 47J years. Ir the large series of angiosarcoma patients described by Mitt at al. the most common symptoms were fatigue, weight lots and abdominal pain.1* The most frequent physical findings wtre hepatcmegsly followed by splenomegaly. Biochem ical profiles (including bilirubin, SCOT. LDH, alkaline phosphatase, $GFT, COT, (stoglobulin and CEA) yielded variable results sod proved to be of little value in the detection or the diagnosis. Thera it a strong indication from the clinical studits that a dose-response relationship exists with respect to the vinyl chloride exposure and human angiosarcoma. This serves as a basis for the current regulations concern ing the atmospheric concentrations permitted in factories. Information, although incomplete, is available on the total , yean of exposure (ranging from 4 to 32 yean) and yean from first exposure to death (ranging from 9 to 32 ytars). From these iota, U it trident that thtrt It a long Latency period of about 10 yearrt which It utuol with earelnogtnle agents, Thlt flgura It of further significance tinea, prtdietably, mtw eatet af viiiyiehlartdt'Ttlattd engiotor~ coma tan ha anticipated In woetart exposed prior to tha introduction af controls. The deaths from angiosarcoma . have occurred over a 14-year time period with an incrcas,* ing number of cases occurring per year. This may he due I to the rapid expansion of the polyvinyl chloride industry, l and also to the awareness in recent yean of this hazard so j that all (or most) new cases are now being reported. The I estimated figure of those stm at risk in the U.S. from previous exposure is given as between 5000-6000 worken ' so that further eases of angiosarcoma can be anticipated. j However, the probability of diagnosing angiosarcoma I may not be very good especially for those who have not ' been exposed to vinyl chloride monomer for quite a few years. There is very little chance of diagnosis being made if the pathologist is not aware of the relationship between angiosarcoma and vinyl chloride, if the hospital and diagnostic facilities art not sophisticated, if the person's medical and work history art not known and if an autopsy Is not carried out In relation to human hepatic angiosarcoma, it is notable that two lesions, namely fibrosis and pcliotis, precede the appearance of the angiosarcoma. There is also evidence hat angiosarcoma of the liver Is not the only tumour asso-Jated with vinyl chloride. Large cell carcinoma of the ung Is now suspected, as is hepatocellular carcinoma, vise, angiosarcoma of the liver is not peculiar to vinyl hloride. Chronic exposure to insecticides containing in- rganic arsenic hat been associated with hepatocellular ircinoma and hepatic angiosarcoma." diagnosed so that effective treatment can be implemented? i Without going into detail, evidence from studies wfch ' rets, Indicates that VCM is altered (metabolized) tad (hn the resulting products (metabolite) are the cairinogcm rather than the VCM itself. Further, (here is tvideacc that the level of glutathione which normally serves to detoxify these metabolites is decreased by VCM, thus freeing (hem to react with other intracellular macromoiecules such as DNA, ENA, proteins and lipids. This is one of the vnBestablished experimental routes by which chemicals cause cancer. It should be emphasized that this evidence is based on studies made with cats and the applicability to human beings is unknown. As for diagnosis and treatment, a number of report* dealing with the clinical management cl worken exposed to vinyl chloride end polyvinyl chloride have been pub lished. It ii agreed that a good medical surveillance pro gram should include a comprehensive medical and occu pational history, and a review of all the systems and in formation concerning alcohol intake, past history of be- ` 'i, past exposurs to hepatotoxle drop and chemicals, K transfusions, etc. A physical examination by a physician, a chest x-ray, x-ray of the bands, a pulmonary function test (forced vita] capacity and forced expiratory volume, 1 see.) and a pane! of laboratory tests including complete blood count, a complete blood cbemistty pr<* file" The special problem of an these examinations lies In the fact that the individual symptoms of all pathologies] manifestations brought into connection with vinyl chloride are not in themselves specific to vinyl chloride. Thus, for example, acroosteolysis, Raynaud's syndrome, scleroder mas and thrombocyte changes have occurred in people who have not been exposed to vinyl chloride monomer. The thrombocyte count of a person can fluctuate considerably within a very short time. Wrong diagnoses are readily made if one reties on that symptom alone. The changes in the liver of vinyl chloride workers are very specific dis turbances -- so-cstled fibroses of the fiver can only be recognized as such by meant of microscopic tissue exam ination of the liver (biopsy)." Liver function tests, liver scant, angiography and liver biopsy deserve special comment. It it well known that the "liver function tests* used in medicine, are not tests of liver function. They only provide crude information on the function and dysfunction of the fiver and no informa tion on its cause. Moreover, since a large segment of the working population drinks, if an abnormality is found,' it is not easy to exclude an ethanol acthiology for this ab normality. Liver function testa are too erode to detect lesions such as the hepatic fibrosis which teems to be the precursor lesion of angiosarcoma; they are also too crude to detea early angiosarcoma. The use of invasive tech niques such engiogrephy and transjugular liver biopsy seem too extreme, ordinary livar biopsy is hazardous m suspected angiosarcoma. Popper recommended the fiver scan as the best single test, it should be done annually (along with the medical examination) on those workers at risk. It would seem reasonable also to do a scan of work ers whh abnormal liver function tests especially if an ethanol cause can be excluded. If a fiver scan Is positive, it should be followed by angiography and if this is posi tive, then surgery is recommended." We have outlined the grots effects of exposure to vinyl Although ft seems unlikely that anyone entering the loride monomer. There art two remaining questions, vinyl chloride work force today wifi develop angiosarcoma hat happens to VCM once it enters an organism (mao or because of the controls thatjfr* In force, new cases are mal), and how are diseases related to VCM exposure [ anticipated in worken previous exposed: continued med- CHEMISTRY IN CANADA.-SUMMER 1977 K 8 S 3 ,V} 1 3 1 i1 4 1 4 ) ucc 047439 fcat corvtOUftC* b important. Since a minimum of 4 yean exposure (initiation pntse) b required and ainee (he pro* motion phase takes about 10 years, it b likely that saw cam will develop over the next 14*15 yean in thb pre viously exposed worker population.** There are essentially three sources of exposure to vfayi chloride monomer. It b emitted into the outside atmosphere (environment) during the maaofaeturing process, workers are exposed to it in the contained atmosphere of the work place, and polyvinyl chloride consumer products under certain circumstances can release > inyl chloride memo* mer into the atmosphere, foods, or solvents such as al cohol. Vinyl chloride emissions into tha atmosphere & Canada have been estimated at 6,000 metric tons during 1973, about 5 per cent of production- Of thb total, it b thought that 19 per cent was released by PVC manufacturing plants and 10 per cent by VCM plants. The remaining 1 per cent was released by the plastics industry during the pro cessing of PVC into finished products and b due to mono mer trapped in tha PVC min. Emissions for 1976 ars less since efficiency has increased to 98 per cent or better. Release of vinyl chloride from the degradation of PVC b insignificant due to the great stability of the polymer. The estimated total entry into the North American en vironment in 1973 was 126,000 metric tons. The physical properties of the compound 0ow boiling point, high vapour pressure and low water solubility) in* dicate that it would migrate rapidly to the air and not he found in appreciable amounts in water or soil. Fhotolytie decomposition in the atmosphere is thought to be the nly significant route for removal of vinyl chloride from the environment The photodegradation half-life under real conditions b about two days. b is possible to calculate the expected concentration of vinyl chloride in ambient air in iht Northern Hemisphere by using the release figures and the half-life of vinyl chlo ride in the atmosphere. For 1973 the calculated ambient steady state concentration in the atmosphere b l.lXtO* ppm by volume (3.6 nanograms/m*)." Total emissions from the three basic industry sectors for the year 1973 were reported as 0.4 per cent from VCM manufacture, 3.5 per cent from PVC manufacture and 0.05 per cent from PVC fabrication, based on 1973 ota! production of PVC. Technology and work prscticas suld reduce these emissions by as much as 95 per cent. Want air concentrations of VCM b not known. On occa sion a universe] dispersion calculation b used by engineers to calculate the ambient concentration of n particular pollutant a ground level. Factors included in thb calcula tion are stack height, ambient temperature, wind, emission rates, half-life of particular substances, etc. Occupational exposure to vinyl chloride may occur b the manufacture of the monomer and also during tha manufacture of PVC Loading nod unloading of tank can and trucks containing VCM and PVC constitute an ex* posure risk. During the manufacture the greatest risk of exposure occurs to workers when cleaning the polymeriza tion kettles. The polymer usually contains unreacted mono mer which b partially given off in the drying process, packaging operation and storage. Residual monomer may be given off during mixing, compounding and extrusion of PVC Excessive heat leads to decomposition of PVC and the formation of hydrochloric add gas, carbon monoxide, carbon dioxide and possibly traces of phosgene end other gases.** Prior to the emergence of the VCM health problem, tittle data were available on the concentrations of VCM to which workers were exposed. However, it b generally accepted that leveb op to 3000 ppm were frequently en countered, particularly in the older resin plants. More spe cifically and according to industrial sources, exposure levels during the year 1970*73 ranged from 35 to 50 ppm with a weighted average of 28 ppm. fat June 1974, 5 per cent of tests read under 5 ppm and 79 per cent over 10 ppm. By December 1975, the situation bad changed: 92 per cent under 5 ppm while only 8 per cent read over 10 ppm and the average had fallen to 4 ppm. Today, following numer ous process improvements and the development of new technology, personnel exposures in Canada are reported to be below 5 ppm. The manufacture of VCM involves a continuous pro cess which for the most pan is open to the atmosphere. In cidents of worker exposure are primarily limited to infre quent fugitive emissions. Vent stacks arc usually elevated and workers are not formally affected. Advanced technology and modified work procedures have resulted in personnel exposures below $ ppm with good prospects or further reductions. Readings below 1 ppm were recently reported for Dow's Sarnia operation." Vinyl chloride monomer emissions are further ease* bed at captive end fugitive. Ceptive emissions an ea or continuous or periodic vtnt streams to maintain -cat control and product quality. Fugitive emissions osses which can come about through leaking flanges, s and pump scab, aad losses during sampling, month loading, and unloading. Captive embtioas relate ily to the intrinsic process or capability of equip* Fugitive emissions relate primarily to equipment ance, operating procedures end discipline. 7 shows typical emission rata (as percentages of wide monomer emitted to the atmosphere) for ive end fugitive losses. The quantitative date dustry performance in 1973, prior to implemcn* ecently-developed technology. sow vinyl chloride mooomer b dispersed out* b unknown. Measurements show a concentre* chloride monomer of 0.1 ppm two-thirds of a e'plant, and no detectable VCM one milt lationship between emission rata and am* TABLE 7 Esmurto vcm Emissions Pawn to New Txcxkoloct Embsjcms^Ti^Per cent) Emission Type or Sourco Manufacture of: VCM I Captive Reactor/Mixer .OS Intermediate Recovery jtM Pioduct Purification/ Recovery 21 Product -- Total Captive 3 Fabricated PVC Products .1 .04 3 1.06 Si. .06 2.1 II Yota! Fugitive 111 Total Emissions ' .1 * A 1.4 SB JtB Source: Arnold 1976, p. 11 N CANADA. SUMMER 1977  r The danger of exposure 10 vinyl chloride monomer gos exists mainly within plants which produce polyvinyl chlo| ride resin. Due to the nature of the "botch" PVC resin proI ducrion process end the frequent need to open vessels, | etmotpheric contemlnetlon bp vinyl chloride monomer got I emissions occurs." in the polymerization process the conI version of vinyl chloride monomer b only 85*90 per cent | complete. Mott of the uareacted VCM b recovered but | amount* of up to 1000 ppm residual monomer are retained | in the resin and are transferred downstream to the fabrics* lion plant* with the resin shipments. A pood portion of the recycled monomer and the remainder b lost to the at* j mosphera inside and outside the plant. { There b very little evidence that VCM his been . prob lem in plastic fabrication plants where PVC resin b used. , Individuals employed by processors are not exposed to ' the leveb of VCM which are present in VCM or PVC plants. Resins with low residual monomer content and J <ood plant ventilation control are responsible for the lew risk in the plastics fabrication industry." However, until recently, a number of the PVC powder pradcs produced by the suspension end bulk polymeriza tion processes contained over 1,000 ppm residual, unre' acted vinyl chloride. Despite degassing after polymeriza tion and high temperatures durinp drying, it b net possible to remove residual vinyl chloride from PVC. This residual ' is partly liberated durinp storage and durinp subsequent ' processing. Consequently incressed concentrstions in the work area cannot be ruled out. By adopting a completely new mode of operation, de cisive. improvements in industrial safety and reductions in the vinyl chloride monomer emissions are possible." A critical operation in the use of PVC b its transfer from the rail car to the fabrication plant. A recent report prepered by the University of Washington's Department of Environmental Health states. "Of the 13 polyvinyl chloride operations located in the state, only the extrusion plants appeared to present po tential exposure problems. It should be mentioned that the six extrusion plants employed 398 workers or ap proximately 80% of the total work force exposed to vinyl chloride. Five of the tlx extrusion plants were sub ject to genera] atmospheric vinyl chloride concentration in excess of the permbsibie exposure limit of 1 ppm. Vinyl chloride concentrations in plant 12 were all well below 1 ppm. The only plant, however, in which person nel samples exceeded the permissible exposure limit was plant 11. The blender in thb plant exhibited a 6* hour time weighted amcrsgc concentration of 4 ppm. The extruder, the belter, and the laboratory technician were at or above the action level of 03 ppm. "The railroad car at plant 10 indicated a vinyl chloride concentration of PI4 ppm when sampled through the piastre cover. Twenty-four hours after the car was opened and partially unloaded, the interior concentra tion was still 70 ppm. The rail car at plant 1 showed 77 ppm f vinyl chloride immediately after being opened and 12 ppm 1 hour after opening.""!' Tn a general environmental health context, concern has been expressed on the possible effects of using PVC prod ucts containing unreacted releasable monomer. Studies have shown the resulting exposures arc insignificant and no ill effects are known to have occurred." In its final form, PVC is'an inert material. That is, it will not revert or depolymerize to vinyl chloride mono- mcr gas. Both the Ontario Ministry of Health and the UA Occupational Safety and Health Administration have stated that finished PVC products "Do Not Constitute Any Known Health Hazard." No evidence to the contrary has been discovered. Products made from PVC have been used by consumers for almost 40 years." In the same con text, retrospective studies have been conducted on certain Ohio dtics with PVC production facilities In order to as certain the oncogenic and mutagenic risks to the popula tion. The results ere inconclusive." Detectable leveb of VCM have been discovered in PVC bottles. Residual VCM gas b known to have migrated into products which are mainly alcohol based. For example, unrcacted VCM has been found in certain PVC bolded wines, distilled spirits end vinegar. No evidence b available to indicate that the occurrence has endangered the health of users. Unreacted VCM has not been found in food wrap when measured by sensitive instruments which detect vinyl chloride monomer down to 50 parts per billion.* Actions Token os the Result of the Percep tion of the Vinyl Chloride Monomer Hazard Three areas Olustrste the response to the perception of the hazards associated with vinyl chloride exposure: 1) setting of standards, 2) industrial activity such as the development of better abatement technology and monitor ing, and 3) research. Vinyl chloride monomer and polyvinyl chloride were introduced in the United States in 1937 and in Canada in 1943. For many years VCM was considered as only slight ly toxic, from both single and repeated exposure." The high flammability of VCM was considered a more serious hazard. The first concentration standards were based on thb criterion of hazard. In 1949, an early Russian study revested a high inci dence of liver disorders among men handling VCM. As a result, a maximum acceptable concentration of 12 ppm was established in the U.S.S.R. Whether thb standard was enforced is unknown. The results of thb study remsined unnoticed because they were iniccessible to other coun tries and they arc still not available in detail." Until 1962, the American Conference of Governmental Industrial Hygienists (ACGIH) recommended that the long-term exposure of workers to vinyl chloride should not exceed 500 ppm with a time weight average of S hours daily. The recommendation was based on single exposure studies on animals and human beings. .In spite of ACGIH recommendations, Dow Chemicals Limited, reduced exposure leveb to 50 ppm on the basis of animal experimentation. In the 1960s industry was atcrled by reports of occupa tional disease among PVC reactor cleaners, namely aero* osteolysis and Raynaud's syndrome. A Manufacturing Chemists Asssociation (MCA) study could not define the role of VCM in causing this condition. However, the vinyl industry sdopted industrial hygiene controls and work practice changes as recommended and new cases of thb disease are almost never seen. In 1963, ibe ACGIH modified their recommendation so that 500 ppm became a maximum concentration (or ceiling) rather than a time weighted average. It b thb value that was in the 1970 threshold limit vshu list promulgated by the Oriupaiit,..l Safety a 72 CHEM1STRV IN CANADA. SI'MM r A* sU IS Wi lir ol 1 P 0 r n V e t ;I \ t iC I i i it !( ucc 047441 : jo c o * u ns Administration m May 29, 1971 at a national comentin standard. The ACGLH proposed in 1970, and affirmed in 1972, reduction of their recommended TLV to a timeweighted avenge of 200 ppm," la Germany, at about the tame time, the threshold limit value was reduced to 100 ppm following the outcome of animal experiments in which liver changes had been noted after exposure to vinyl chloride." Or. Viola's work In 1V6 was the first indication of .anccr in connection with the exposure to vinyl chloride. UtUe attention sms paid by industrial hygienists to Viola's report of the carcinogenic potential of vinyl chloride be cause his investigations were conducted with extremely large dosages." A year later hi Europe, the Manufacturing Chemists Association (MCA), Montedison, Imperial Chemical, Solvay and Rhone-Frolif, initiated research to be con ducted by Dr. C. Maltoni with the agreement that the in formation discovered would be shared among them, but not revealed without their consent Even though MtltonTs results were available in August 1972, and shared with U.S. scientists in January 1974, the National Institute of Occupational Safety and Health (NIOSH) was not notified nor was any attempt made to warn the public or workers of risk. Further experimental results in November 1973 and in May 1974 confirmed Maltonfs 1972 findings." In January 1974 when B. F. Goodrich reported three cases of angiosarcoma in workers exposed to VCM at their plant in Louisville, Kentucky, the problem received world wide attention and concentrations for occupational ex posure were reduced aU over the world. During May 1974, West Germany adopted a standard of 30 ppm. Shortly afterwards the threshold limit value regulation for vinyl chloride was discontinued and a tech nica] guiding concentration of S ppm as an annual average was fixed." In Britain, a time-weighted TLV of 30 ppm in the work environment was imposed. A comprehensive code of prac tice in February 1973 was issued at a result of the forma, lion Of a joint w-orking group of unions, management and i the Inspectorate. In October 1973 a new hygiene standard | was adopted: a ceiling level of 30 ppm; a time-weighted TLV for VCM of 10 ppm, and a policy that exposure of workers should be brought as near at possible to zero con centrations. To evaluate the extent of the hazard within Britain, three studies have been set up: a prospective study of PVC manufacturers, a prospective study of PVC fab ricators, and a retrospective study of primary angiosar coma." In tbe U.&, after the Goodrich announcement, the most expensive and comprehensive measures ever undertaken to deal with an industrial health hazard wera mounted. } Virtually all of the U.S. National Institute of Occupational Safety and Health (NIOSH) field teams were mobilized to undertake epidemiological (group health) studies of vari ous PVC plants." , An emergency standard of 23 ppm time-weighted aver age with 30 ppm maximum exposure was set by June 1974. Permanent levels were then set by OSHA, NIOSH and trade unions (JUD of the AFL/CIO, OCAW, URW) in February 1974. It was recommended in the U.S. that the acceptable threshold level of VC to be allowed in air be set at no detectable level (in reality a 1 ppm. standard)." OSHA proposed a standard for personnel exposure to VCM of I ppm, time weighted average over eight hours, in October 1974, including a maximum *, ppm over 15 minutes. This regulation became effective in April 1975, and fat April 1976 lbs peak limit was re duced to 5 ppm before tbe use of respirat ty equipment become* necessary." Therefore, tbe U.S. value went from 500 ppm to 50 ppm sod then to 1 ppm between 19$t and 1974. The EPA has promulgated final standards limiting air and water emissions of vinyl chloride from new and existing plants. Vinyl chloride emissions win bt limited to 10 ppm under the final standards and require the use of the best avaiiible technology." However, the EPA standard for vinyl chloride has been challenged by the Environmental Defence Fund (EDF) which has filed a petition in tbe U.S. Court of AppeaL The petition is based on Maltonfs latest findings which suggest that mammaty carcinomas can be induced in laboratory animals at 1 ppm or lest. According to the EDF, the EPA standard is based on tha degree of control which can be achieved through use of best available control technology and not on the de gree of control which is necessary to protect public health. This it contrary to the Clean Air AcL" Generally, Canadian response occurred after the 1974 B. F. Goodrich announcement. Canadian regulator* be came awsr* of the vinyl chloride hazard through their American counterpart* and the Canadian aubsidiarie* through their American parent companies. The media pro voked a response, u well at scientific publications and exchange*. At the federal level in Canada, because of a more lim ited workplace jurisdiction, the response has been slow. The Product Safety Branch of the Department of Con sumer and Corporate Affairs, after learning of tha deci sion early in 1973 of tha U.S. Consumer Product Safety Commission on harmful effects of household sprays using VCM at a propellant, immediately banned the importation, sale, and advertising of aerosol packaged chemical products which contained vinyl chloride as a propellant gat. Infant toys and pacifiers emitting detectable amount* of VCM were alto banned. The Bureau of Chemical Hazards of the Department of Health and Welfare alto responded in 1973. After its re searchers discovered traces of vinyl chloride in plastic vinegar and peanut oil containers; it asked the packaging industry to modify their packages and then banned the use of packaging in which vinyl chloride monomer could be found." Further, all foods containing detectable amounts of VCM due to PVC wrapping is to be rejected when anal yzed using the official method of analysis (May 1976). Environment Canada is in the process of developing criteria to establith an emission rate standard for VCM and PVC plants that is distinct from an ambient air standard." ' In Canada, the provinces generally have jurisdiction over conditions in the workplace and over health delivery and health protection systems. Thus, it is possible that provincial responses do vary a* shown in Table S. TABLE t Canadian VCM Exrastntc Limits Provinca B Hr. TWA IS Min. Peak Effective - ppm - ppm Data Alberta British Columbia Ontario Quebec S 1 10 1 10 Oct. 197S 6 In Draft Stage 25 Oct. 1974 5 In Proposal Stage rwFMtCTRv in r*vtn* cmtMFi t. , ucc 047442 SI The Ontario Ministry of Health established vinyl chlo the Ontario Cancer Treatment and Research Foundation ride exposure limits guidelines. Upon recommendation participated in the meetings. In March 1975, representa from the Ministry of Labour it win enforce such guide tives of the Province of Quebec, and in mid-1975 of the lines in the workplace. The Ministry of Health issued an Alberta Government, were included. occupational health data sheet to industry and industrial The Society of the Plastics Industry of Canada drafted a associations which includes precautions to be taken io the paper on vinyl chloride which was sent to government, in workplace. Inspecton have the power, under the Public dustries and the media. That started the process of ab Heahh Act, to enforce recommended precautions. The lishing pertinent regulations. In Ontario where the stand Ontario Ministry of the Environment has set up and is en ard b 10 ppm, efforts were exerted to decrease actual forcing an ambient air guideline for vinyl chloride emis Jeveb to 0 ppm. In Use last three years, leveb have de sions nf 0.1 ppm over a 24-hour period with a peak limit creased from the hundreds to under 3 ppm. of 0.2 ppm over 30 minutes. Plant directors have been in formed of this guideline and given time to allow them to develop adequate controls to comply ' th the standard when it b set. The guideline will be it' force until ade quate information is gathered to set appropriate standards. In 1974 the Society of the Plastics Industry of Canada established e Canadian Industrial Committee composed of the industries producing end using vinyl chloride. An open exchange of monitoring and control techniques took piece. Since B. F. Goodrich spent $42 million on vinyl chloride The Quebec Ministry of Labour under the Industrial and Commercial Establishments Act b responsible for standard setting and enforcement. The Environment Pro tection Service inspects the workplace and recommends when enforcement action should be taken by the Ministry of Labour. The Ministry of Social Affairs is responsible for conducting medical examinations of worken if re quested. When and if an already proposed regulation on the quality of the "occupational environment" is made into technology, it b available only on e licensing basis." Information meetings on the subject of vinyl chloride and angiosarcoma have been held not only with plant and maintenance personnel; but with people from outside trucking firms handling the product" VCM gas and PVC min producers today provide or are implementing con tinuous round-the-clock monitoring of vinyl chloride monomer gas leveb within the plant work environment Similarly, work b going on to reduce exposure leveb law, the Ministry of the Environment will be responsible through e combination of engineering changes, new work for standard setting and enforcement. This draft regula practices and personnel monitoring devices carried by tion contains a series of standards and regulations among workers on the job. Improved systems to minimize VCM which b the proposed standard for vinyl chloride of 1 emissions, cither in plant or outside, ere being installed." ppm, time weighted over S hours with a ceiling value of 5 j ppm for 13 minutes. Currently, the Environment ProiecI tion Servlet b monitoring the B. F. Goodrich plant at j Shawinigan and reports that the average exposure levels are 3 ppm. They have also given the company an informal objective of 1 ppm to be reached by July 1977. The legal standard according to the regulations of the Industrial and Commercial Establishments Act b still 200 ppm. In the U.K. developments that have occurred were im provements in monitoring techniques and control engineer ing. Prior to the B. F. Goodrich announcement monitoring was carried out irregularly, and was accurate to about 200 ppm. More accurate techniques of gas chromatography were soon introduced, and could measure to about 10 ppm. Eventually the accuracy was improved to 50 ppb. Monitoring b now carried out continuously, in such a ' Industry's response to the vinyl chloride monomer situa tion, especially since the B. F. Goodrich announcement in 1973, has been dramatic in actions to reduce exposure to j \inyt chloride monomer. In 1974 in the U.5. when a | standard of no detectable level of exposure was recoinj mended, industry responded by suggesting such a stand1 ard was unrealistic and if Imposed would cost the industry way that the levels are known to workers immediately. It b intended that "alarm" systems will soon be introduced. Control engineering concentrated on improved ventilation systems, reducing leakages at valves, and finding ways of cleaning the kettles by high pressure water systems. These developments arc continuing slowly, due to delays and shortages of the necessary pieces of equipment." j right out of business. However, industry was subsequently In early 1974 techniques to measure vinyl chloride mo I able to meet exposure levels that were far lest than they nomer in the low parts per million range were not generally j claimed could be met without altering the market price of known. New instruments, methodology, and methods to PVC resin. The U.S. standard as promulgated by OSHA collect air samples had to be developed. Over the past two b 1 ppm time weighted over I hours with a 5 ppm maxi years numerous pieces of equipment have been introduced mum over 15 minutes. and/or applied to VCM measurement. Gat chromate In Canada and especially in Ontario, the controversy over standards does not appear to have takan place. In dustrial spokesmen have indicated that the 10 ppm guide graphy appears to be the most popular technique and b now sensitive to 0.01 ppm or better." Selected employees fas the vinyl chloride unit st Dow line for Ontario can easily be met and in faet actual ex posure levels have been reduced to about 3 ppm using best practicable technology. Spokesmen from Canadian industry feel that the Ui, standard eannot be met unless gas masks arc used or unless .exposed workers are placed in pure air chambers for a few hours each day. Chemicars VCM and Esso'i PVC plants in Sarnia wear personal monitoring devices (badges) which measure their exposure to vinyl chloride during an S-hour period. Anal yses of the badges are done at the end of each day so that any excessive exposure b quickly spotted and appropriate remedial action can be rapidly taken. Augmenting this procedure b an automatic area monitoring system which After the B. F. Goodrich discovery, the three vinyl checks 30 points throughout the plants on a quarter-hour, chloride producers in Ontario met to discuss what steps to half-hour or hourly basis. Results arc compiled by a com take. They initiated meetings with the federal and the puter and are made available to all employees working in Ontario governments in July 1974. The departments in volved were the Ministries of Health, Labour and Environ ment at the provincial level and the Ministries of Health and Welfare and Environment at the federal lo.. the area through monthly operating reports, monthly safety meetings and periodic communications meetings." I* -Mi-te VCM *. * -esin production work- I" once >, year, ucc 047443 medical examinations developed by experienced fiver and cancer specialists to detect early signs of disease. Eaten* sive industry.sponsored medical research to better tinder* stand the pathology and early warning symptoms of VCM related disease bas begun.* Polyvinyl chloride resin producers have made and arc continuing to make progress In reducing residual vinyl chloride gas trapped m PVG This will eventually elimin ate potential workers exposure In processor plants. Thar* b an intensive international research and development program sponsored by companies and industry associa tions." Improved recovery of the unreactcd monomer teas gives priority for three basic reasons: to reduce the risk of em ployee exposure; to reduce emissions of VCM to the out ride atmosphere; and to reduce the level of residual mono mer in resins and compounds, which lowers the possibility of exposure at fabricators plants and in finished products. Worker exposures were first reduced by providing im proved plant ventilation, probably because it was the fastest and simplest thing to do. New technology had to be de veloped for monomer recovery and reduced levels of residual VCM in tht finished resins. It appears that significant changes have been made in campling techniques and rail ear loading procedures. Continuous monitoring systems throughout the plants pro vide an early warning system of fugitive emissions and process upsets enabling quick remedial response. Refinements are being made in automatic reactor cleaning devices to reduce the frequency of vessel entry for manual cleaning. New technology designed to reduce or eliminate a polymer build*up on reactor walls is in place or is being introduced in varying degrees throughout the industry. This will reduce the frequency of openiog vessels and wifi cut down or eliminate cleaning time. Further, in April 1975, Esso introduced an instripping process which will shortly be installed in alt Esso and Goodrich plants in Canada. The basic technology is not new but advancements arc being made in the elimination of resin build-up or skin on the reactor walls which is the major cause for the need to open and manually clean the vessels by the addition of chemicals which prevent this build-up. This development trend coupled with automatic cleaning facilities that use water under high pressure have permitted the industry to advance to larger reeetors. In recent yean reacton have increased in size from 2000 gallons to 50,000 gallons." Special provisions ara in place to accommodate emer gency situations such as ruo-away reacton and rupture disc failures. The ultimate impact of tht new technology and process changes is reported to ensble a 95 per cent reduction from 1973 level* of VCM released into the en vironment. B. F, Goodrich b licensing its stream-stripping process which removes VCM from FVC suspension resins. Monssnto has been b'censing its FVC reactor cleaning knowhow. Lonza, a Swiss company, U offering a procedure for preventing suspension resin polymer build-up on reactor walls. Tenneco bas developed a carbon absorption method aimed at recovering the residual VCM In vent gas streams. The economics of installing another method of scrubbing VCM from stack gas, called oxypbotolysis b being evaluated. It b unlikely that companies will reap great financial benefits from licensing new technology but they hope to defray pan of th'e development costs." There it no ques tion that the various VCM abatement programs have added to increased costs In all manufacturing segments. Research and development, capital expenditures, operating cocts, maintenance and continuing medical surveillance of tba workers have all contributed to higher production costs." Most vinyl chloride related research in Canada b con ducted by Dr. F. Ddlormc at H&pita] Rfgiooale da la Mauricic and Dr. G. Tbiriauh at Univcrritf LavaL They are focusing their research on the epidemiology of VCMrelated diseases end on diagnosing pre-angiosarcoma tumors. H. Fluggc, a graduate student in the Department of Chemistry at the University of Guelph, working for Dr. S- Safe, b studying how vinyl chloride and its metaboUtas might interact with nucleic acids to product cancer. In other words they are trying to determine the causal finks between exposure to vinyl chloride and cancer develop ment Health and Welfare Canada b net researching any spe cific aspects of vinyl chloride. By amalgamating informa tion and data from a variety of sources, Healih and Wel fare alerted Environment Canada and provided it with necessary background information to assist that agency in establishing emission standards. The Ontario Ministry of Health receives and surveys data from the medical surveillance of workers by the compa nies producing VCM and PVG Most other vinyl Chloride research including epidemio logical work, animal studies and abatement technology b carried out by U.S- university laboratories sponsored by industry and by U-S. industrial in-bouse research facilities. The information which results from these research acti vities b distributed to their Canadian subsidiaries. The Msnuficiuring Chemists Association, the Society of the Plastics Industry, individual companies, and pro ducers in the V.K. end Europe have ail embarked on re search programs. Within the North American plastics in dustry alone, hundreds of scientists and technicians are employed full-time on intensive research programs aimed at developing new technology which will reduce VCM exposure and residual VCM in FVC resin. The combined cost of these programs is estimated to be in excess of 5100 million over the next three years." Msltoni. in Italy, is still actively engaged in establishing dose response curves using animal studies. Summary Conclusion This overview has attempted to outline, as factually as possible, the nature and scope of the problems associated with exposure to vinyl chloride monomer, as wall as what has been done. We now summarise tbt vinyl cbloridc story and attempt to draw soma conclusions by denoting some of tbe deficiencies in the system, by suggesting some "lessons learnt" from the VCM experience, and by argu ing for tome reform. Polyvinyl chloride b a resin wed in the fabrication of a wide variety of plastic products, with tremendous com mercial success. It is manufactured by tbe polymerisation of vinyl chloride monomer, a relatively simple synthetic organic chemical. Since World War n, production of both VCM and FVC has grown at a tremendous rate. Worldwide production of FVC in 1974 exceeded 18 biUion pounds. Up to 1973 vinyl chloride monomer was considered rela tively safe even though effects such as aeroosteolytis, Raynaud's syndrome, had been noted. Removing workers from exposure often eliminated or lessened these effects. In December 1973, B. F. Goodrich in the U-S. received a CHEMIST-V ... fiNADA, SUMMER 1977 ucc 047444 35 Ik medical report that oo of it* worker* had died of a cate of liver cancer, angiosarcoma. Upon checking, the company found that two other employee* bad died from a similar came. After further research, VCM was identified as the causative agent Toward the end of January 1974, the company publicly announced these findings. A worldwide search has so far revealed forty.eight victims, ten in Can* ada. Others who may have died of angiosarcoma are on* known because of difficulty hi diagnosing the disease: Prior to the announcement, studies had shown that VCM had chronic effects on human beings at high levels of exposure. VCM causes a specific occupational disease known as acroosteolysb in which there is both Raynaud's syndrome and sdcro-deimiform lesions. Actually, as far back as 1949, Soviet studies had shown a higher incidence of liver malfunction among workers exposed to VCM. lo May 1970, Or. Viola In Italy announced that VCM caused cancer in test animals. His findings were virtually ignored. Or. Mahonih findings. In Itsly, that VCM is indeed a carcinogen, were made public by industry only after the B. F. Goodrich announcement The B. P. Goodrich announcement precipitated a flurry of publicity in the media. Response from governments, in dustry and labour was quick snd generally cooperative. More stringent standards were set, abatement and moni toring technologies were either put in place or efforts to develop them started, and a wide variety of research in areas ranging from biomedical to technical was funded and initiated. Is the Vinyl Chloride story a sucecss story? If one views it from late 1973 on, ft appear* to be a partial success lory. It has shown hew weak federalism snd different con figurations of economic factor* and organisational power result in different standards snd responses. It docs not tel] us much (yet) about actuat compliance to workplace stand* ards, since most of the new, recently lowered, standards are still being implemented. Their effectiveness snd sus tainability are still questionable. One thing appears certain -- if the current standards are being met (there is no rea* son to believe that they arc not being met in Canada), the risk associated with exposure to VCM has been substan tially reduced. Whether the risk has been eliminated or ft at an acceptable level ft difficult to determine since a dose response curve for worker exposure to VCM hat, at yet, not been established. It has been argued that exposure to any amount of a known carcinogen ft unacceptable, la any case, anyone now entering the workplace, where ex* posure to some vinyl chloride is probable, suffers a very small risk of contracting a VCM-related disease, or at least a much lesser risk than those who entered the work place prior to 1973. Prom this point of view, the vinyl chloride story ft a sucecss. However, are the future victims from past ex posures, going to be identified and compensated? This is a complex issue because of the long latency period before angiosarcoma becomes evident, because of the difficulty in disgnoting the disease, because of die relatively poor records of exposure that were kept In the past, and be* causa of the transitory nature of employment in contem porary society. .. Viewed holistically, the claim that the vinyl chloride stoty ft a success becomes rather dubious. It bas long been known that nearly all halogenated hydrocarbons represent a hazard to human health. In 1949, 1958 and 1965 reports from the Soviet Bloc revealed a variety of disorders in wo.kcrs exposed to VCM; in the mid*1960( .number of reports dealt with changes in VC resemr ele*n?.n; in 1970, Or. Viol* in animals. Despite these reports, up I 1973, k was the general conclusion that exposure to VCM teas not a sa* rious health hazard. If blame ft to be apportioned for ignoring the signs that VCM ft a carcinogenic hazard, ft should ha shared by nearly everyone involved. Governments by their relative apathy and lethargy in the occupational health arena; business and labour by turning a Mind eya toward this problem area, usually because of commercial and economic motives (profits and employment); end the scientific world, because of its ivory tower approach to these problems, have an been equaHy guilty of neglect. Occupational health has not been ignored, but the ma jor emphasis has been given to dramatic, acute effects and not to the long-term sub-chronic effects of low levels of exposure. With hindsight It is evident what should have been done -- the signs should have been heeded. Much more research, epidemiology and testing should have bean undertaken. Information flow should have been facili tated and obligatory so that information was readily avail, able. Occupational medicine (diagnosis and treatment of occupational disease), industrial bvgiene, and monitoring need to be given added emphasis. Most important, attitudes toward industrial chemicals (whether new or old) and pro* cesses must take into account, when costing an industrial development, the potential for harm over the long term. Testing a chemical for its potential as a carcinogen ft lengthy and costly. A hierarchy of tests based on a sense of priorities needs to be established. Research directed toward developing quick and relatively inexpensive means of identifying chemicals that are harmful over the long term should be initiated. Promising developments are taking place. There are two prime lessons to be learnt." The first is that vinyl chloride ft only one of a great number of diemieah harmful to human beings which have been or ere thought to be safe. It is startling to note that the corre lation between exposure to vinyl chloride snd angiosar coma *v made only because that form of cancer ft rare. Had the cancer been more common, ft ft likely there would still be no awareness of a linkage. Studies have shewn that there ft a relationship between primary cancer of the liver and the presence of chemieah in the environment." Thus, determining the frequency of carcinoma due lo exposure and identifying those chemicals that cause carcinoma in the work and market places are questions of prime impor tance. Recent estimates by the World Health Organization indicate that 60 per cent of ail cancers arc induced by pol lutants which are not viruses. However, cigarette smoking, admittedly, ft probably responsibla for a large but un known proportion of environmentally-caused cancers. The second "lesson to be learnt" from the vinyl, chloride experience is thst there ft an urgent need to improve our anticipatory capacity. For far too long, the prevalent prac tice has been one of reaction. The existing method of using people, whether workers or the public, as guinea pigs for the hazards of industry, although it ft not done overtly, ft insupportable and unacceptable. Chemicals most, as far as possible, be tested prior to their Introduction into the work and market places, particularly because of the delayed appearance or cancer. This emphasis on anticipation should not de-cmphaslza epidemiological research. On the con trary, this sort of research must be strengthened to enable us to determine what already exists and to confirm that future precautionary measures are satisfactory. The prob lems, obstacles and difficulties in conducting epidemio logical studies are formidable, but must be overcome. For relying on routine health records and death 38 CHEMISTRY IN CANADA. SUMMER 1977 ucc 047445 7 certificates u they are currently constituted would probably provide "false negative" findings end incomplete infer* health occur at different levels of exposure. It also helps determine the future, type and comprehensive ness of the control measures required. The study of the vinyl chloride case naturally leads to -- There should be bo restrictive definitions of what a number of other lessoos and arguments for change.* constitutes an industrial disease. For example, h would a -- International recognition and acceptance of Just wbat constitutes an industrial hazard should be established. be unfair to confine the recognition of an occupational causa to a tingle histological type, which would deny Since the field of industrial hazards Is so vest, soma compensation to a worker suffering from another re attempt at rationalizing an international effort should lated type. The identification of new occupational can be made -- possibly through the auspices of the United cers underlines the need for a restudy of compensation Nations, multinational corporations and international laws. One particular concern is that the latency period trade unions. The latter group should have a particular of occupational cancers often exceeds the Statute of {merest sines workers usually do not receive corapea* Limitations for the filing of workmen's compensation sation unless such recognition is given. yiiiiHi -- Basic research carried out by people with no vested -- Workers and the affected public must participate fully interest internationally and nationally must ha estab at every level of discovery of the variety of industrial lished. The information should be made readily avail- hazards: They should he kept informed of the latest afata to all concerned in any nation. developments In industrial and environmental safety. -- Soma of the research on industrial chemicals must be TTadc unions and labour organizations, in particular, conducted In a manner which is related to the work environment Most chemicals are tested in isolation should participate as equals with management in meet ings dealing with the latest developments in industrial i from other chemicals and in a manner unrelated to the worker's dietary and non-work-related, physical con ditions. some of which may predispose him or her to hygiene, in monitoring and controlling the exposure to hazards and, in certain instances, in the design of a new technological development to ensure that aD wards a particular hazard. Both retrospective and pros needed safety precautions are included, pective research should be initiated. The former will -- Finally, standards of expo-tire should be promulgated attempt to identify and verify all diagnosed eases of and enforced by governments. While a standard should primary angiosarcoma of the liver and to evaluate reflect what has come to be perceived as an acceptable their association with occupational exposure to vinyl risk. It should be flexible so as to adjust easily t new chloride. The litter will evaluate the effects of ex findings. Also there must be a capability to monitor posure to vinyl chloride in terms of mortality and can a standard if it is to have any meaning. The prime ia- cer registration rates, by including all past workers who may at yet have no symptoms, from every factory manufacturing polyvinyl chloride.** quirement must be protecting public health rather than exhibiting the degree of control existing technology can achieve. -- Adequate and appropriate medical services (including diagnostic) mutt be msde available to workers to that Conclusion occupational diseases can be identified at the earliest This overview emphasizes the occupational aspect of stages: exposure to VCM, because that is where the major problem -- The worker, the unions and the public should be di is. Exposure to VCM outside the workplace, does not, as rectly informed of the type of harmful effects that yet, eppeir to be a threat to health. This does not mean it could result from substances, processes or phenomena should be ignored. Recent findings by Maltoni, that con to which they ere exposed. This win assist them in de centrations of VCM of 1 ppm or less can cause mammary ciding whether the risk associated with such exposure cancer, indicate it may be necessary to review emission is acceptable. Further, this information needs to be and ambient air standards. made available so that the people involved will be aide If the vinyl chloride story tells us anything, it it that to recognize occupational and environmental nineties we may be facing a crisis, one brought on by the plethora when they occur and thus be able to identify, record, of new chemicals that are being introduced in the market investigate and correct the conditions. and work places and about whose hazardous properties -- Information flow between the medical-scientific, gov- little if anything is known. This is a challenge that must vemmentai, industrial, labour, and public communities be met by a dedicated effort by all involved -- unions, should he as free and as open as possible, especially in management, health authorities, governments and tha aH matters pertaining to human health. Governments scientific community. The lessons from the vinyl chloride having two major responsibilities la this regard. They experience should he learned. Safety costs money -- its f mutt ensure that the information they have obtained H neglect often costs lives. available and accessible. Secondly, they* must obtain i the release of information held by others. It Is sug i gested that the Department of Labour be responsible federally for information pertaining to the health of tit Armatt, TithiW at Vh|l OferMt la Ih IhIim. alI.I*tnaiW lu it. Stlaa Cwwfl at Canada, u.| 1IU, aw workers; perhaps by some amendment to the Labour Code. In the broader area of public health, the De l A- a. GlWra, tufa a/ tha Alt Bran Kapaatt Tlarl ChlafUa CaUSaama amt Ahatwaat TaaKaalau, Zailmaial Ottawa, Aarfl. ISIS. partments of Health and Welfare, and Environment . AnaM, tf ait. M S. . should hold responsibility. 4. ArwaM. *p. dl. a L -- Reliable exposure data must be included in the analysis of the correlation between the degree of exposure to chemical hazards and subsequent health effects. This is required as a basis for revcMin* v** affects on - Clmaltat Wat, US (*t), IS Jama, 1111. *. It. I Y'i axiIBsa. StrCiaal liadi af Vlarl ChlaiM*. t>rr*i<4 fat tha Btknaa Caaacll af CaaaSa, Jama ISIS, r. 1, t, S. A Varbani Kaavauffinniiih laSiulft*. VC/BVCl Aa tnalW af a rnkkB Sbulnt, ftmmklmn. Vai G>mr, ml, p. a. CHEMISTRY IN CANADA. 51': UCC 047446 S7 sir* i*. Ckkrife. Ka*v.inMuBttaau.) iHijmhknDbwlam**,r Hrm*kIUrun4T dTfhaHn feJu,4^ tuy*;,M IK to U. Ilk ST vTSilkM, ImbHM *4 Om OhmomiI *** CiMnrinliMili to to OX. OXA, **l totoT *S hniiikf Irfimn to |to UmM luito, Oitonlf to Ku> ,, Asto. Allot 1IT4 to CM. t ^ *a4: g3tCtMrtito", rntNton ( ik* Itrd Mitr *C IKSCto*.*Ct..nu, _M.. SttMii . *M, to 4 a teasOktort* IflkUtoy to HmMA Tlurf CktoiM* Nimm, B*to____ #11. 0<fk**ttok*l JfMltk Inunin Srnck. Motor, 1114 to L Mt'CnmI, Imi full Atovt Vtoil CktoiM*. Mo mn *4 PtlrrU?) Cktorll*. Dm Unto, Oati-ia. II Marak 1114 P* 4k afc^vVVk.11 n. laylinM--Uj-l---H-----h--k----I--I-I- toI fttjr Km, Tlwl CM*rM* I**ti#*. _ Si*- tJjMtolto to WaiUkftok, SmUto. 0-4, Itomto 1111, to A 14 Crin*r4 M, dt. to 14 *M*. CHatari, *a. lit, cmU, *)|n, . . *u . t, 14 Pliitto laiaatrr CaanclL **. cH, a, 4 14 ArmiM, . tot: tol4^ T. C. CJvntrkMk, "DtoIk to Ik* l*iUa l*4*rtT7". Baikal tokaa* .a VL.4* UJU, 1114 to *4 14 AmaM. *to att. . 1L 14 14 Vka*4 *to M, to 14 ii* ^wrkMk> # dt, to to. Hi rum#*, #. tot, to n. 44 VtikanA n. tol_ *. 14 44 IrUl.k kalltal JaanaaV, -Yto,l Cklarilai Ik* **rda*s*al* lUT, .. !?. . to 114 Sebnc* Ccuncll Committ## on Hozordeus SubrtiMM el Mm-MiIi Origfai ChmlrmMMi Mtmbtrr. David V. Bales, Member o( the Science Couocfi. Dean of MedidD^ ' Uaiveralty of Britith Columbia. John E. Abitt, Executive Vice-Preiideat, E110 Cbemlcab. Oordou C Butler* Director, Biolofical Divisloo, National Research ConoriL famea M. Ham. Daaa, School of Craduate Studies, University of Toronto. F. Kenneth Hare, Director, Institute of Environmental University of Torooto. Studies, Terence 0. bon. Professor, Faculty of Law, Queen's University, Past Director, Workmen's Compensation Board, Britith Columbia. - ----- itoiki Ki*t "ZmIuIm Ball* a*i far tbrl eklarila . a*L M, a*. 41, 1 KartaUr 1114 to 4 <4 CnTlrtkmalal llaalth Uiur. 1 D*t*tok*r 1114 to 4 44 *. Dam, Xanlalair Ff*aa*a** aal larialktkaal laaaaa to tk* m. MXaralalUaa *1 Haui!rla"ai *Plditli to Caaa4a,,.TAt- n*p*artw uf*it*| A. J. Kantd, Directcur, Centre regional de toxicologic, Universitl Laval. ll. J"W# Ik* Jfoa-PaMi* Saalaar *a Ttoto CkkrW*, SdMm aa Cana4a, Otto**, I 1*1w 1114 W. 4 *. " SB?--! " *vl cltortto. Dm Ck*a* u {&&& 'S i a M. Mamllioto >. toC a, 4 !.' nkL11** CraadL #. dt, p. 4 II. AnaM. *to dt, n. 11.14 *4 ~C*:tia* *t Ik* Uat Uaaaa at VCkP, Ckaakal Wart, 111(1). 11 11. ArnMA a*. *| p, 14 <4 PJaiiia. I*ls*ny Caaaclt, *. alt, a 4 *4 c. P^ Tk4rtau(l^ P. J. Jaart, "Dlatrikotlaa to >rla* aaaaan to tka Pmlm at Qwrttt", Canalla* Malkal Aawdattok JnwU , wl.llt I Frtniarr 1171. 4 1*4 * 5 71^*4*54 ?** *U5TM,"* w*Mlato", Aakto, T*l 4. M. 4 14i- f- / ^"***J. "taMamtokclal Ittoto" fnmdan *f Ik* Karat Maw d Malkiaa. V*LII, A>ftl 1114 **. ni3l4 CorneUum Rtimer, National Director, Oil, Chemical and Atomic Workers Union. H. Rock* Roberlion,' Member of the Science Councfl, Past Principal, McGill University, Working Paper Jack Basuk, Prepared for the Science Adviser, Committee by: Science Council of Canada. With the Assistance of: ADoe Nichols Research Assistant ucc 047447