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EPA-Expo-Box (A Toolbox for Exposure Assessors)

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Chemical Classes

Exposure assessment is one of the four major steps in risk assessment; others include hazard identification, dose-response assessment, and risk characterization. Exposure assessment is “the process of estimating or measuring the magnitude, frequency, and duration of exposure to an agent, along with the number and characteristics of the population exposed. Ideally, it describes the sources, routes, pathways, and uncertainty in the assessment” (EPA'sGuidelines for Exposure Assessment and IPCS, 2004 Glossary of Key Exposure Assessment Terminology (122 pp, 951KB, About PDF) developed by the International Programme on Chemical Safety). 

Exposure may be estimated for chemicals in any of a variety of chemical classes: pesticides, other organics, inorganics and fibers, or nanomaterials. Tools related the various chemical classes are provided in EPA-Expo-Box. Alternatively, exposure assessments may be categorized according to exposure assessment approaches, exposure media, exposure routes, assessment tiers or types, or lifestages and populations.

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