Document 4aw69M1zBVb63J9nqwqVxjrke

CMm CHEMICAL MANUFACTURERS ASSOCIATION '/*A December 26, 1989'' Dear Vinyl Chloride Panel: Enclosed, for your Information, Is a copy of the summary and conclusions of the' BUA Report on Vinyl Chloride-(Beratergremium fur Umweltrelevante Altstoffe, Federal Republic of Germany, 1989). The BUA is recommending no additional ecology or toxicology testing in the FRG. Please call me at 202/887-1293 if you need additional information. Sincerely, Susan R. Howe Manager Vinyl Chloride Panel 2501 M Street, NW, Washington, DC 20037 202-887-1100 Telex 89617 (CMA WSH) GENC 005859 I bv CMA CIZ&SZVA DIVISION Hrij --- -Jz^k-BajodK-.i .u. ------------- TV:: BUA Report on Vinyl Chloride i i \ Summary ind Conclusions f ` ECOLOGICAL ASPECTS b > Production, entry Into, occurrence and distribution In the environment 9 v In the Federal Republic of Germany, the vinyl chloride production J sms up to nearly 1.5 million tons In 1987. About 99 A are used for > subsequent polymerization to polyvinyl chloride and copolymers. The T remainder (about 9,500 - 12,700 tons) Is required for the synthesis , of 1,1,2-trlchloroethane. For the region of the Federal Republic of Germany, the vinyl chloride ` discharge Into the atmosphere can be estimated to about 330 tons per * annum, 9 % of which are due to the monomer production, 91 % are due ' to the production of polyvinyl chloride. About 4 tons per year are * released Into the air when processing PVC, owing to Its residual monol mer content. * The entry of vinyl chloride Into waste water can be estimated at 25 J 30 tons In 1987. About 7 % of the amount discharged can be attributed t to the production of the monomer Itself, whereas about 93 % Is assoclI ated with the production of polyvinyl chloride. The waste water Is ! treated In biological sewage treatment plants In which vinyl chloride evaporates as a result of Its physical properties. Generally, vinyl l chloride Is not detectable In the effluent. | In surface waters, vinyl chloride can be traced In Individual cases | only. For the Rhine, maalwm concentrations of 1 pg I*1 have been * reported before 1978; in tributaries of the Rhine, maxlwm coneentrai tlons of 5 |ig l"1 of vinyl chloride have been detected. QENC 005840 In the Federal Republic of Germany, vinyl chloride generally cannot be detected In potable waters. Concentrations of op to 1.7 pg l"1 recorded In Isolated cases seen to be dee to prolonged exposure tines In PVC pipes with an elevated background level of non-polynerlzed vinyl chloride. Vinyl chloride form as an Interaedtate during the biological break down of tetreehIoroethane and trichloroethane. In these cases, It can be detected In groundwater and at dumping sites In seeping water and as a gas conponont. j Recent Investigations have revealed vinyl chloride in the ataosphere In concentration ranges fron *not detectable* (< 0.3 pg a'J) to 15 pg n`3. gg percentile values of up to 69 pg u"3 have been reported. Due to Its physlco-chenlcal properties, vinyl chloride util nalnly evaporate Into the ataosphere. Degradation The abiotic degradation In the ataosphere via photocheaica1-ox(dative reaction aost probably foras the aaln degradation pathway. For this process, the half-life can be calculated at 2.2 to 2.7 days. Based on available experimental data the half-life of the hydrolytic degradation of vinyl chloride dissolved In water can be estlaated to several years. Biodegradation of vinyl chloride takes place by neans of specialized, adapted bacteria. Bioaccuuulation XIM The bloaccuaalatlon factor ranges from < 10 for fish to 15 - 30 for Invertebrates and 40 for algae. These results Indicate a low potential for bloaccinaulatlon and btonagnification. Ecotoxlc effects Gaseous vinyl chloride displays uutagenic effects towards plant cells, the threshold value Is 194 ng m'3. During anaerobic sewage treatnent, a first retardation of gas produc tion can be seen between 5 and > 64 ng I'3 vinyl chloride. The 96 h LC^-values for fish lie between 1.1 g l*1 and 1.2 g I"1. The present data on the ecotoxtcologlcal properties of VC are United to the results of laboratory studies. Data obtained by studies In the outdoor environment are not available. GENC 005361 i XIV toxicological aspects Vinyl chloride depresses tlM centra) nervous systea. Due to Its cardi ac side-effects. It has not been used as an anaesthetic. The acute toxicity of vinyl chloride Is low; following a 2-hour Inhalation expo sure, the LCgg values were 294 ng I'1 for alee, 290 ng l'1 for rats, S9S mg I*1 for guinea pigs and 295 ag for rabbits. Liquid vinyl chloride causes hypothere!a of the skin, w'h-ic*h *Is s-ta>ll*e--r xto.. Mfr_o_sat Injuries of the second degree. Furtheraore, vinyl chloride can cause teaporary Injury to the eye. Vinyl chloride Is oxidatively aetabolltad to chloroethylene oxide (chlorooxlrane) catalyzed by cytocbroae 9-450 dependent aonooxygenases. Since this reaction Is saturable at relatively high concentrations (2.56 ag/1) it is regarded as the Halting step in the netabollsa of vinyl chloride. The alkylating potential of chloroethylene oxide to wards DMA suggests this aetabollte being responsible for the autagonlc and probably also the carcinogenic effects of vinyl chloride. Hetabotfcatty unchanged vinyl chloride is alaost quantitatively ex haled. As additional aetabolltes chloroacetaldebyde, chloroethanol and cblo- roacetlc acid were also identified. f|' The aetabollc foraation of chloroethylene oxide per unit of tlae Is 5 - 10 fold higher In rats and alee than In nan. This phenomenon can be explained by the higher activity of the aonoxygenase systea In rodents coopered to aan. Vinyl chloride showed autogenic effects in laboratory anlaals and In various short-tera assays In vitro. The ultlaate eutagenlc aetabollte Is chloroethylene oxide (vide supra). *sv Following Inhalation vinyl chloride Induced aalnly haemanglosarcomas of the liver (primary target organ) In rats, alee and boosters, with feaale rats and alee being clearly aore susceptible than males. Fur thermore liver tumours, extrahepattc angiosarcomas, lung and manaa tumours were observed In rats and alee. The Incidence of hepatocellu lar carcinoaas was higher In male animals. 2ymba1 gland tuaours, neuroblastomas and nephroblastomas were exclusi vely observed In rats, whereas forostomach tuaours wore seen In rats and hamsters. In addition some melanomas were hlstopatbologlcally Identified In boasters. * Following oral application a sialtar tumour spectrum was observed. The Induction of tuaours appeared over a wide dose range. The afnfaat tuaourlgenlc concentration after Inhalation of vinyl chloride was 0.0256 ag 1'* In rats, 0.13 ag l'1 In alee and 1.2B ag T* In ham sters. After oral application (vinyl chloride aonomer adsorbed on PVC) a atntaal affective dose of 1.7 ag kg"* body weight was observed In rats. Animal experiments gave no evidence of teratogenic effects of vinyl chloride. Long term occupational vinyl chloride exposure at high concentrations occurring In some workpieces before the 1970's caused haemanglosarcomas of the liver end damage In other organs. The range of diseases observed in aan later was collectively called "vinyl chloride disease*. The main effects included periportal fibrosis of the liver, changes In the distal vasculature of the hands, manifested by the development of Raynaud's phenomenon, scleroderma or acro-osteolysis. GENC 005862 XVI Sine* 1975, when the occupation*! vinyl chloride concentrations were reduced to some ppm, no new cases of the 'vinyl chloride disease* have been reported. A statistical slgnifleant correlation between vinyl chloride exposure in the workplaces and the development of angiosarcomas of the liver, a stldomly found turner In nan, has been established. Since then, occupational exposure has been largely reduced due to technical safety Measures, the 'Technlscbe Rlchtkomentration (TRXMert)* in Nest Germany is now 5 eg m"3 (S mg m'3 In existing VC mono- mer and PVC production plants). 1 Since the first appearance of the hsemangiosarcomas In nan, about 140 cases have bee* observed worldwide until 1988, Including 32 cases in Hast Germany. Single tumour* are expected even in the next decade, due to the long latency period and the high vinyl chloride concentra tions in workplaces before 1974. I ti' RECOMMENDATIONS XVII Esalaut Only few data are available regarding ecotoxicological effects of vinyl chloride. Under this aspect, a comprehensive assessment is not possible. However, due to the physico-chewical properties (rapid evaporation from aqueous sources) vinyl chloride will not accumulate in water. Negative long tore effects are thus not to be expected here. Out of this reason nore experiments regarding the ecotoxicology of vinyl chloride do eot soon to ho appropriate. Due to Its short half life In the atmosphere no additional experiments with gaseous VC are necessary. iM&iilglY The toxicological knowledge acquired to date Is regarded as sufficient and therefore no additional testing is recommended. 0056-63