How is exposure to PCBs evaluated?
To evaluate exposure, the Agency looks at the concentration of PCBs in fish, water, soil, sediment and air; the frequency with which an individual may come into contact with the media; the length of time the individual may be exposed, and the bodyweight of the individual. For carcinogens, the exposure is averaged over a lifetime. For non-carcinogenic effects, exposure is averaged over the portion of the lifetime during which the exposure occurs. Depending on the data available, separate analyses can be developed for children, adults and lifetime exposure. The data used in the assessment may be based on actual concentrations in the fish, soil, etc. It may also be based on modeling that projects future concentrations. Information on exposure activities may be developed using national or local surveys of activities (i.e., fish consumption). The result of the exposure evaluation is a calculated level of dose for each route of exposure.
