Document xj96YYqrp08zVJXqGReBORmO1

2d ^technical week European Chemical News. May 24. 1974 CIA argues case against zero Therefore the committee's work is being focused on the VCM poly merization process itself. It estimates VCM exposure limits that average atmospheric concentra tions in the UK were 1 000 ppm in the 1945-1955 period, 400-500 ppm in 1955- aatt aa hprwesms kbpriweAfinnga Kh*e1l/d1 Ilansett hw/meeIkt iinn Ape*nnettrraattiAioUn ,of PVC in to a wide range 1960, 300-400 ppm in 1960-1970, 15.) London on vinyl chloride (VCM) toxi of market applications, as a major ppm in mid-1973, and is now 50 ppm. city the UK Chemical Industries Asso industrial material where alternatives Major improvements in the past six ciation (CIA)'s vinyl chloride ooromittee are not available in the quantities nor months have come mainly from the stresnd that the PVC industry would in most cases with the properties elimination of procedures which per stop dead if society demanded zero required, the CIA stated. mitted vinyl chloride to escape into the exposures to VCM in the production, The four UK producers of PVC are plant atmosphere (within the prescribed fabrication and use of PVC to elimin so far spending over 4m. this year to limit of 200 ppm). ate the risk of industrial injuries. reduce the maximum possible atmo- The vinyl chloride committee, which spheric concentration of VCM exposure was set up about three months ago. to--paBt 'operatives to 25 oom hv has as its terms of reference, "to volume, from the existing lent limit enquire into the nature and extent of of~VCM exposure oTi the hazard to health of vinyl chloride, Cuiietiliy, 12 cases of angiosarcoma whether in the free state or as a con of the liver (a rare liver cancer) have stituent of polymerized material. been discovered in the USA, one in the Secondly, to establish in collaboration UK, and around five in continental with expert bodies both in the UK Europe. These diagnoses (two cases are Application Tahiti: UK uao at PVC In 1*71 Toaaaqo id MaIa imi Marittk still surviving) have occurred over a tenyear period. Ultimate Levels Further improvement will come from detailed plant modifications to eliminate or reduce adventitious leaks, according to the CIA committee, with the ultimate for most existing plants at 10 ppm. However, entirely new plants using the latest available technologs might achieve 5 ppm, as the lowest possible level attainable, the CIA states. In contrast, OSHA, the US Govern ment body concerned with the VCM % Of the 18 cases, problem has just proposed a standard Pipe* 4 fittings 100 000 (30 000 mite* of plpoworfc) Electric cablo* 40 000 Water main*, rainwater pip*, oil plpa, electrical conduit Houaa wiring* motor vehlcl*#, X seven have occurred of less than 1 ppm for atmospheric ao on one plant in the VCM levels. The proposal is however 75 25 100 USA (B. F. Good open to public comment before being rich), a further three adopted as law and the US Society of 100 in another US plant the Plastics Industry has already re Hard flooring '30000 m dom**tk applianc**, power cabte* Til#* 4 continuous vinyl flooring 70-00 40-50 00 (Goodyear), with the sponded by calling the now standard incidence elsewhere "excessively and unrealistically restric being very low. tive." Packaging Average exposure Up till now a temporary limit of 5{> (a) Foil 4 film . 34000 Foil: margarlna tuba, biscuit#* chocolate* Fllm:fro*h most 4 vagaiabtaa lime of the known ppm has been established in the USA cases approaches 20 Nevertheless a limit of less than 1 ppm years. However, the is tantamount to a zero exposure, and fb) Bottle* 13000 (400m. bottl**) (c) Bottl* dotur** BQOO Raeorda (phonographic) 21 M0 (140m. record*) Cart 90000 Footw#r 90000 70m. pair* Fruit sgusah, cooking oil. swoot lore. food ond drink product* all rtcorda ar* PVC Upholstery* roof Interior* wiring Shoo* (35%) nnd *ho* upper* 20*25 60 50 30 100 05 100 levels of vinyl chloride monomer to which these workers were exposed, thought to be at least 1 000 ppm,, is ex tremely high com:pared with present permitted levels. therefore zero risk. The CIA stresses that it is impo-sihle to prove a zero risk In the case of VCM there has always been some risk, as VCM presents a fire and explosion risk very similar to that of butane and other liquefied gases used for heating and lighting. There hasc been more deaths from fire and explosions of such Colliery 0 000 conveyor belting (about 1 00Q mliet) Underground .r*ty bolting' 100 -- Aveirage exposure . materials than from industrial disease levels in-the UK are and in the case of VCM. on a world now 5j>pm.for plant wide basis, more people hase uied from and overseas as well as with govern atmospheres in VOTT production. 50 these causes in the past ten years than ment departments, the actions neces ppm in plant atmospheres for produc from cancer, the CIA committee stateu sary to safeguard die health of workers tion of PVC from VCM. and generally As far as fabrication of PVC is con and users and to make recommenda 0-5 ppm in plant atmospheres for fabri cerncd, the CIA is recommending that tions for their speedy implementation." cation of PVC articles Vinyl chloride fabricators achieve atmospheric concen A major reason for the committee's absorbed in a human diet is about 0-001 trations of less than 5 ppm. Howewr. determination to arrive at a satisfactory ppm of the diet the fact remains that the concentration solution to the VCM carcinogenity Thus the CIA considers that the of VCM in freshly-produced PVC es- problem is the importance of PVC to problem, if one still exists, is confined plant is in the range of 200-400 ppm the UK national economy. to the industrial process of converting by weight, although the lesel drops on Four companies, BP Chemicals, IC1, VCM into PVC. Levels in food are storage. British Industrial Plastics and Vinatet infinitesimally small, and atmospheric Typical levels on delivery to a siisu. (jointly owned by the National Coal Board and Conoco), produce 400 000 ton of PVC annually in the UK, in volving 2 000 workers. exposure levels in the fabrication in dustry, where they may at present exceed 5 ppm, can easily he reduced by improved ventilation, the CIA main mer arc around 250 ppm. nut aft .processing this drops further to 'onrwhere between 0.5 and 20 ppm in weight, depending on the lubrication Table I shows the extent of the tains. involved. ucc 006847