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Last Edited: 9/6/2002

What is an exposure assessment?

Exposure assessment is the process to ascertain the total exposure to individuals from a given source of living or working in a certain area. Exposure assessment involves numerous techniques to identify a pollutant, pollutant sources, environmental media of exposure, transport through each medium, chemical and physical transformations, routes of entry to the body, intensity and frequency of contact, and spatial and temporal concentration patterns of the pollutant. Exposure can be estimated in three ways. For air exposures, it can be evaluated directly by having a person wear a device that measures the concentration of a pollutant when it comes into contact with the body. Environmental monitoring is an indirect method of determining exposure, in which a chemical's concentration is measured in an environmental medium at a particular site and the extent to which a person is exposed to that medium is used to estimate exposure. Finally, exposure can be assessed using a biologic marker.