The Environmental Health Sciences Center is a focal point for research on the biological impact of toxic substances in the environment. The work supported by this grant concentrates principally on the behavior of chemical agents after introduction and on their biological effects after uptake by target organisms into the environment. The core activities of the Center are feasibility or pilot studies, research support in analytical chemistry, statistics, animal resources, and pathology, program enrichment through development of collateral research and public information programs, and administration.