Characterizing the Uncertainty in Estimates of PCB Risk from the Consumption of Fish Taken from the Clinch and Tennessee Rivers. J. I. McCrodden, P. S. Price, N. L. Bonnevie, J. D. Avantaggio, and E. S. Ebert, McLaren/Hart - ChemRisk, 1685 Congress Street, Portland, ME 04102
Due to historical releases of polychlorinated biphenyls (PCBs) from DOE activities at Oak Ridge, TN, PCBs have contaminated Poplar Creek, and the Clinch and Tennessee Rivers. As a result fish have accumulated PCBs. A preliminary risk assessment indicated that anglers consuming the fish may be at risk. To further refine these risk estimates, we developed a Monte Carlo model of the uncertainty associated with the estimates of PCB exposure and associated risks. As part of this effort, we identified several key populations who represent high-end consumers of fish. Our model considered both the uncertainty due to the lack of data and the variability between one individual and another in each of the exposed populations. We developed distributions, including site-specific distributions of fish consumption rates, to reflect the interindividual variability. Our results represent the uncertainty in the risk estimate for a randomly selected individual, and suggest that certain angling populations may have been at risk for the carcinogenic and noncarcinogenic effects of PCBs. Additional studies are planned to investigate the location and exact size of the angler populations as well as the uncertainty in the toxicological criteria used to estimate the risks.