(615a) Environmental Release and Occupation Exposure Models Used in Chemical Risk Evaluation

Under the Toxic Substances Control Act (TSCA), the US Environmental Protection Agency (US EPA) is required to determine whether a chemical substance poses an unreasonable risk before the chemical is manufactured in or imported into the United States. This presentation will provide an overview of the environmental release and occupational exposure models used by the US Environmental Protection Agency (USEPA) to conduct chemical risk evaluations under the Toxic Substances Control Act (TSCA). Additionally, this presentation will provide an overview of methods used to model occupational exposures and environmental releases as part of the chemical risk evaluation process used in other jurisdictions, along with work being performed to improve these models. Finally, the alternative methods to evaluate occupational exposures and environmental releases that may be used as part of the decision-making process regarding a chemical are identified. The contribution provides a path forward for reducing the time required and improving the chemical evaluation of the unreasonable risk determination regarding the manufacture or import of a chemical.