VINYL-CHLORIDE MECHANISTIC DATA AND RISK ASSESSMENT - DNA REACTIVITY AND CROSS-SPECIES QUANTITATIVE RISK EXTRAPOLATION

Vinyl chloride produced several tumor types among species. Angiosarcom a of the liver is found in all tested species, including humans with o ccupational exposures, Vinyl chloride is biotransformed by CYP2E1 to D NA-reactive chloroethylene oxide producing cyclic etheno adducts, whic h are mutagenic, The dose-response for angiosarcoma of the liver forma tion in rodents is supralinear, which is consistent with saturation of metabolic activation, and the tumor rate in humans at occupational ex posure levels is similar to that for equivalent exposures in rodents.