A cohort study of Swedish capacitor manufacturing workers exposed to polychlorinated biphenyls (PCBs).

Mortality and cancer incidence were investigated among 242 male capacitor manufacturing workers, exposed to polychlorinated biphenyls (PCBs) for at least six months between 1965 and 1978. Mortality and cancer incidence were followed from 1965 to 1991. There was a significantly increased mortality from cardiovascular diseases among those employed for at least five years in high-exposed jobs, with a latency of 20 years. There were two cases of cancer of the liver and bile ducts, which previously has been associated with PCB exposure, both in epidemiological and animal experimental studies. No data on smoking habits were available. The study supports some previous findings of an increased risk of cancer of the liver and bile ducts after exposure to PCBs. The reason for the excess of cardiovascular deaths in the high-exposure group is not known and deserves evaluation in future studies.