A Cancer Risk Assessment of Low Level Vinyl Acetate Exposure Utilizing a Physiologically Based Pharmcokinetic Model

Vinyl acetate (VA) is widely used in the chemical industry for the manufacturing of polyvinyl acetate emulsions, copolymers with ethylene for adhesives, and paper coatings. The International Agency for Research on Cancer (IARC) has classified vinyl acetate as a possible human carcinogen (IARC, 1995). There is sufficient evidence in the literature to indicate the carcinogenic potential to rats exposed by inhalation to vinyl acetate. There is limited epidemiological data to support a possible excess risk for cancer of the respiratory system with long-term exposure to industrial workers. In order to estimate more closely the risk at current occupational levels, a physiologically based pharmacokinetic (PBPK) model was constructed to predict human target tissue concentrations at plausible industrial exposures. These concentrations were then characterized and compared to tissue levels corresponding to doses known to be tumourigenic in animals to arrive at an estimation of human cancer risk. The model demonstrated that daily low level exposures to vinyl acetate pose a minimal threat of cancer risk to workers.Master of Science in Public Healt