Vinyl chloride, hepatotoxicity

Vinyhdene chloride is hepatotoxic, but does not appear to be a carcinogen (13—18). Pharmacokinetic studies indicate that the behavior of vinyl chloride and vinyhdene chloride in rats and mice is substantially different (19). No unusual health problems have been observed in workers exposed to vinyhdene chloride monomer over varying periods (20). Because vinyhdene chloride degrades rapidly in the atmosphere, air pollution is not likely to be a problem (21). Worker exposure is the main concern. Sampling techniques for monitoring worker exposure to vinyhdene chloride vapor are being developed (22). 

Liver cancer can also be a consequence of exposure to hepatotoxic chemicals. Natural hepatocarcinogens include fungal aflatoxins. Synthetic hepato-carcinogens include nitrosoamines, certain chlorinated hydrocarbons, polychlorinated biphenyls (PCBs), chloroform, carbon tetrachloride, dimethyl-benzanthracene, and vinyl chloride.Table 5.15 lists the chemical compounds that induce liver cancer or cirrhosis in experimental animals or... 

Liver cancer, from vinyl chloride contact, 25 651. See also Hepatotoxicity Livestock industry, feed ingredient usage by, 10 837t Live vaccines, 25 487... 

There are many different types of toxic compounds producing the various types of toxicity detailed in chapter 6. One compound may cause several toxic responses. For instance, vinyl chloride is carcinogenic after low doses with a long latent period for the appearance of tumors, but it is narcotic and hepatotoxic after single large exposures (see chap. 7). 

Hepatic Fibrosis/Cirrhosis Fibrosis usually results from chronic inflammation which can be the result of continuous exposure to a variety of hepatotoxic chemicals such as organic arscnicals, vinyl chloride, or high doses of vitamin A (Zimmerman, 1999), chronic ethanol ingestion and nonalcoholic fatty liver disease. Fibrosis usually occurs around the portal area, in the space of Disse, and around the central veins. This results in loss of liver architecture and function. The hepatocytes are replaced with fibrous material and thus there is hepatocyte loss. Periportal fibrosis may lead to portal hypertension. 

The adverse effects of tetrachloroethylene are similar to those of carbon tetrachloride (CQ4), but less severe. Tetrachloroethylene is hepatotoxic and neurotoxic, but gastrointestinal disturbance is the only common adverse effect when it is used carefully. There is some risk of addiction to the inhaled vapor inhalation can result in vascular reactions, loss of consciousness, pulmonary edema, and fatal hepatic and renal damage. Alcohol and fatty foods increase absorption and hepatic toxicity. Exposure to tetrachloroethylene has been known to lead to vinyl chloride disease. Allergic reactions have not been reported. 

Reynolds ES, Moslen MT, Szabo S, et al. 1975. Hepatotoxicity of vinyl chloride and... 

Organ toxicants primarily affect one or more organs or body systems. For example, many chlorinated hydrocarbon compounds are hepatotoxic (i.e., Uver toxicants). Carbon tetrachloride and vinyl chloride. 

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