(688d) Review of US Environmental Protection Agency General Exposure Scenario Modeling for Evaluating Chemical Safety

Generic Scenarios were initially developed by the US Environmental Protection Agency (USEPA) as a part of the chemical risk assessments process required under the Toxic Substances Control Act (TSCA) used by the USEPA to evaluate the hazards associated with the modeled chemical. From these humble beginnings, Generic Scenario documents have evolved into Organisation for Economic Co-operation and Development (OECD) Emissions Scenario Documents (ESDs) produced to describe a chemical’s sources, production processes, pathways and use patterns. This presentation provides a review of exposure modeling performed in the development of existing Generic Scenario documents. This review was conducted to understand the evolution of the Generic Scenario process, with a goal of simplifying the modeling approaches used to estimate exposure levels and human health effects related to manufacture and use of chemicals currently required under the Lautenberg Chemical Safety for the 21st Century Act.