The workshop on endocrine disrupter research needs: a report.

On April 10-13, 1995 the US EPA sponsored a workshop to develop research needs for endocrine disrupters. Participants were assigned to discussion groups for health effects issues and risk assessment methodologies. The neurotoxicology workgroup identified several chemicals including the PCBs and dioxins that affect nervous system function possibly by acting on the endocrine system during development. The study of endocrine disrupter is confounded by a number of uncertainties, including the presence of chemical mixtures in the environment unclear exposure parameters, poorly understood mechanisms of action, poor dose-response characterization, and uncertain animal-to-human extrapolation. The working group proposed a research strategy to address these uncertainties, which includes initial identification of effects of concern to human and/or wildlife populations and determining whether those effects can be associated with exposure to specific chemicals in the environment and neuroendocrine disruption. Once a problem chemical has been identified and the exposure conditions established, hypothesis-driven research to determine mechanism of action could proceed.