Application of a population-based toxicity quotient approach with field validation to assess potential effects of PCBs to great blue herons
- McLaren/Hart Environmental Engineering, Portland, ME (United States). ChemRisk
As part of an ecological risk assessment of a river ecosystem contaminated with PCBs, potential effects of PCBs on a population of great blue herons were evaluated using two independent measurement endpoints. The first measurement endpoint was a population-based toxicity quotient, in which predicted dietary intakes of PCBs for herons at six colonies within foraging distance of the river were compared to a literature-based toxicity reference value. While toxicity quotient approaches generally use default exposure factor values to predict potential risks to hypothetical individual organisms, in this application the use of some site-specific exposure characteristics of an actual population yielded an estimate of potential risks to the population as a whole. The second measurement endpoint considered reproductive success as a function of distance of heron colonies from the contaminated river, based on data collected by the state fish and wildlife service since 1979. The results of the two measurement endpoints both indicate that reproductive success is not likely to be adversely affected by the current level of PCBs in the river system. Given the independence of the measurement endpoints, as well as the robustness of the field data set and the site-specificity of the toxicity quotient calculation, uncertainty in this analysis is substantially reduced relative to more traditional screening level risk assessment methods.
- OSTI ID:
- 242313
- Report Number(s):
- CONF-9511137-; ISBN 1-880611-03-1; TRN: IM9626%%141
- Resource Relation:
- Conference: 2. Society of Environmental Toxicology and Chemistry (SETAC) world conference, Vancouver (Canada), 5-9 Nov 1995; Other Information: PBD: 1995; Related Information: Is Part Of Second SETAC world congress (16. annual meeting): Abstract book. Global environmental protection: Science, politics, and common sense; PB: 378 p.
- Country of Publication:
- United States
- Language:
- English
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