| Popis: |
The U.S. Environmental Protection Agency has developed a framework for ecological risk assessment and proposed ecological assessment methods for certain chemicals (e.g., 2,3,7,8-TCDD) and applications(e.g., Great Lakes Wildlife Criteria). However, criteria for screening ecological risks in regulatory decision-making have not been proposed for RCRA or CERCLA. This analysis presents a methodology for developing ecological screening criteria for wildlife (i.e., medium-specific exposure concentrations designed to be protective of wildlife). Multiple levels of biological organization are considered by selecting physiological endpoints that may be used to infer impacts to populations, communities, and ecosystems. A suite of ecological receptors is identified in two generic ecosystems (freshwater and terrestrial) likely to receive significant exposures to chemical stressors based on dietary habits and/or ecological niche. For nine pilot chemicals, ecotoxicological benchmarks are established for ecological receptors, including representative species of birds, mammals, soil fauna, fish, benthos, and plants, based on a review of toxicological data on wildlife and laboratory species. |
