A spatially-dynamic preliminary risk assessment of the American peregrine falcon at the Los Alamos National Laboratory (version 1)

摘要

The Endangered Species Act and the Record of Decision on the Dual Axis Radiographic Hydrodynamic Test Facility at the Los Alamos National Laboratory require protection of the American peregrine falcon. A preliminary risk assessment of the peregrine was performed using a custom FORTRAN model and a geographical information system. Estimated doses to the falcon were compared against toxicity reference values to generate hazard indices. Hazard index results indicated no unacceptable risk to the falcon from the soil ingestion pathway, including a measure of cumulative effects from multiple contaminants that assumes a linear additive toxicity type. Scaling home ranges on the basis of maximizing falcon height for viewing prey decreased estimated risk by 69% in a canyons-based home range and increased estimated risk by 40% in a river-based home range. Improving model realism by weighting simulated falcon foraging based on distance from potential nest sites decreased risk by 93% in one exposure unit and by 82% in a second exposure unit. It was demonstrated that choice of toxicity reference values can have a substantial impact on risk estimates. Adding bioaccumulation factors for several organics increased partial hazard quotients by a factor of 110, but increased the mean hazard index by only 0.02 units. Adding a food consumption exposure pathway in the form of biomagnification factors for 15 contaminants of potential ecological concern increased the mean hazard index to 1.16 ({+-} 1.0), which is above the level of acceptability (1.0). Aroclor-1254, dichlorodiphenyltrichlorethane (DDT) and dichlorodiphenylethelyne (DDE) accounted for 81% of the estimated risk that includes soil ingestion and food consumption Contaminant pathways and a biomagnification component. Information on risk by specific geographical location was generated, which can be used to manage contaminated areas, falcon habitat, facility siting, and/or facility operations. 123 refs., 10 figs., 2 tabs.