Objectives: The objectives of the study were to assess exposure to polychlorinated biphenyls (PCB) among workers involved in the removal of old sealants containing PCB and to evaluate the related long-term health risks by means of quantitative risk assessment.
Methods: Workers' exposure via different exposure routes was estimated from air and material samples and exposure calculations. The health risks were evaluated using unit risks and a reference dose based on animal tests and evaluations made by the Environmental Protection Agency in the United States.
Results: The estimated exposure of the workers was higher than that of the general population. It was about 10-fold higher than the reference dose and average dietary intake (both 0.02 microg/kg-day). The calculated point estimate of excess cancer risk was 4.6 x 10(-4) cancer cases per lifetime.
Conclusions: The estimated excess cancer risk among workers was low, although the PCB exposure of these workers was higher than the dietary intake of the general population. This quantitative risk assessment method can be used to evaluate the health risk of groups of workers by occupational health professionals.