Update of the follow-up of mortality and cancer incidence among European workers employed in the vinyl chloride industry

Although vinyl chloride is an established cause of liver angiosarcoma, the evidence is inconclusive on whether it also causes other neoplastic and non neoplastic chronic liver diseases as well as neoplasms in other organs. Fur thermore, the shape of the dose-response relation for angiosarcoma is uncer tain. We have extended for approximately 8 years the mortality and cancer i ncidence follow-up of 12,700 mate workers in the vinyl chloride industry in four European countries. All-cause mortality was lower than expected, wher eas cancer mortality was close to expected. A total of 53 deaths from prima ry liver cancer (standardized mortality ratio 2.40, 95% confidence interval = 1.80-3.14) and 18 incident cases of liver cancer were identified, includ ing 37 angiosarcomas, 10 hepatocellular carcinomas, and 24 liver cancers of other and unknown histology. In Poisson regression analyses we observed a marked exposure response for all liver cancers, angiosarcoma, and hepatocel lular carcinoma. The exposure-response trend estimated for liver cancer in analyses restricted to cohort members with cumulative exposures of < 1,500 parts per million-years was close to that estimated for the full cohort (re lative risk of 2.0 per logarithmic unit of cumulative dose). No strong rela tion was observed between cumulative vinyl chloride exposure and other canc ers. Although cirrhosis mortality was decreased overall, there was a trend with cumulative exposure.