Probabilistic risk assessment of sustainable fish consumption at sediment sites.

A probabilistic risk assessment (PRA) using a range of sustainable usual fish consumption rates (SUFCRs) was performed to evaluate the potential health risks from consuming resident fish at two contaminated sediment sites. The analysis focused on the Portland Harbor Superfund Site, a large river in Oregon, and Koppers Pond, a small pond in New York. At both sites, the sediment cleanup remedy is driven by PCBs in resident fish. The PRA fit probability distributions to inputs used to develop a distribution of SUFCR, the long-term fish consumption rate sustainably supported by a fishery, and other exposure parameters to calculate the range and likelihood of cancer risks and noncancer hazards for adult anglers. At the 95th percentile, which is often considered a reasonable maximum exposure (RME), the SUFCRs calculated using site-specific inputs are six- to ten-fold lower than the point estimate fish consumption rates used in the deterministic baseline human health risk assessment conducted for each site. The combination of sustainable fish consumption rates and probabilistic methods results in a range of risks and thereby provides more information than the more commonly used deterministic approach. For over 99% of the resident fish-consuming population, the potential cancer risks and noncancer hazards calculated in the PRA are below the deterministic estimates for the RME adult consumer at each site. The combination of PRA with the estimation of SUFCRs is a novel application of these techniques at contaminated sediment sites that provides critical information for risk management decision-making. Integr Environ Assess Manag 2023;19:830-843. © 2022 AECOM Technical Services, Inc and The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Application of probabilistic risk assessment: Evaluating remedial alternatives at the Portland Harbor Superfund Site, Portland, Oregon, USA.

A probabilistic risk assessment (PRA) was performed to evaluate the range of potential baseline and postremedy health risks to fish consumers at the Portland Harbor Superfund Site (the "Site"). The analysis focused on risks of consuming fish resident to the Site containing polychlorinated biphenyls (PCBs), given that this exposure scenario and contaminant are the primary basis for US Environmental Protection Agency's (USEPA's) selected remedy per the January 2017 Record of Decision (ROD). The PRA used probability distributions fit to the same data sets used in the deterministic baseline human health risk assessment (BHHRA) as well as recent sediment and fish tissue data to evaluate the range and likelihood of current baseline cancer risks and noncancer hazards for anglers. Areas of elevated PCBs in sediment were identified on the basis of a geospatial evaluation of the surface sediment data, and the ranges of risks and hazards associated with pre- and postremedy conditions were calculated. The analysis showed that less active remediation (targeted to areas with the highest concentrations) compared to the remedial alternative selected by USEPA in the ROD can achieve USEPA's interim risk management benchmarks (cancer risk of 10-4 and noncancer hazard index [HI] of 10) immediately postremediation for the vast majority of subsistence anglers that consume smallmouth bass (SMB) fillet tissue. In addition, the same targeted remedy achieves USEPA's long-term benchmarks (10-5 and HI of 1) for the majority of recreational anglers. Additional sediment remediation would result in negligible additional risk reduction due to the influence of background. The PRA approach applied here provides a simple but adaptive framework for analysis of risks and remedial options focused on variability in exposures. It can be updated and refined with new data to evaluate and reduce uncertainty, improve understanding of the Site and target populations, and foster informed remedial decision making. Integr Environ Assess Manag 2018;14:63-78. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Fish consumption as a driver of risk-management decisions and human health-based water quality criteria.

The use and interpretation of fish consumption surveys and interviews, the application of fish consumption rates for sediment evaluation and cleanup, and the development of human health water quality criteria (HH WQC) are complex and interrelated issues. The present article focuses on these issues using examples from the United States, although the issues may be relevant for other countries. Some key considerations include the fact that there are many types of fish consumption surveys (e.g., 24-h recall surveys, food frequency questionnaires, creel surveys), and these surveys have different advantages and limitations. Identification of target populations for protection, identification of the species and quantities of fish consumed, and determination of bioaccumulation assumptions are important factors when developing water quality and sediment screening levels and standards. Accounting for the cultural importance of fish consumption for some populations is an even more complex element. Discussions about HH WQC often focus only on the fish consumption rate and may not have broad public input. Some states are trying to change this through extensive public participation efforts and use of probabilistic approaches to derive HH WQC. Finally, there are limits to what WQC can achieve. Solutions beyond the establishment of WQC that target toxics reduction from other sources may provide the greatest improvements to water quality and reductions in human health risks in the future.