Risk assessment in a federal regulatory agency: an assessment of risk associated with the human consumption of some species of fish contaminated with polychlorinated biphenyls (PCBs).

The problem of polychlorinated biphenyls (PCBs) became a national concern in 1971 when several accidental contaminations of foods were reported. Extensive efforts were undertaken by FDA to reduce the residues of PCBs in food. However, the PCB levels in several species of fresh-water fish have raised concern about the PCB residues from environmental contamination, and it is this concern which has prompted a reassessment of the human risk involved from consumption of such fish. The human epidemiology and animal toxicity of PCB exposure are reviewed, as well as risk assessment in general. Specific examples to risk assessment involving extrapolation of animal data to humans, based on several levels of human exposure to PCBs in fish, are presented.