Ecological Indication, Bioaccumulation, and Phytoremediation as Tools for Environmental Quality Management

摘要

The DoD currently has an estimated 12,000 sites that require some form of remediation related to production activities, field usage, and disposal of military unique compounds (MUCs). Chemical methods to explore types and levels of contamination, and chemical/physical and mechanical methods for cleanup of contaminated soils and sediments exist, are very costly, but do not give insight in environmental toxicity. We explore biological methods that can: (1) indicate toxicity (level and spatial extent), bioaccumulation and potential for trophic transfer; and (2) remove contaminants by root uptake, subsequent transport to shoots, and degradation, or prevent contaminants from leaving the site in whatever form, such as leachate, runoff, trophic transfer (phytoremediation). We use risk assessment to evaluate the toxicity and need for cleanup. Cleanup costs are expected to greatly exceed the cost of evaluation, but to decrease with a decrease in uncertainty to reach the cleanup targets. At present, strategies are under development for evaluating the potential hazards of MUCs to terrestrial organisms/wildlife (risk assessment). These strategies require exposure-based effects data that can be used for defining criteria or reference values, and can also be used as a basis for environmental management. Studies were conducted to provide data for predicting exposure-based effects of explosives, spread via representative components of increasing trophic levels of a relevant, terrestrial food chain. The goal of these studies is to determine if concentrations at a site might be harmful to indigenous species. The trophic levels studied include plants, soil invertebrates, and mammals.