US EPA

Exposure scenarios are a tool to help the assessor develop estimates of exposure, dose, and risk. An exposure scenario generally includes facts, data, assumptions, inferences, and sometimes professional judgment about how the exposure takes place. The human physiological and behavioral data necessary to construct exposure scenarios can be obtained from the Exposure Factors Handbook (U.S. EPA, 1997a). The handbook provides data on drinking water consumption, soil ingestion, inhalation rates, dermal factors including skin area and soil adherence factors, consumption of fruits and vegetables, fish, meats, dairy products, homegrown foods, breast milk, activity patterns, body weight, consumer products, and life expectancy.

The purpose of the Example Exposure Scenarios is to outline scenarios for various exposure pathways and to demonstrate how data from the Exposure Factors Handbook (U.S. EPA, 1997a) may be applied for estimating exposures. The example scenarios presented here have been selected to best demonstrate the use of the various key data sets in the Exposure Factors Handbook (U.S. EPA, 1997a), and represent commonly encountered exposure pathways. An exhaustive review of every possible exposure scenario for every possible receptor population would not be feasible and is not provided. Instead, readers may use the representative examples provided here to formulate scenarios that are appropriate to the assessment of interest, and apply the same or similar data sets and approaches as shown in the examples.