Exposure Assessment

Abstract

Exposure assessment is a critical step in the risk assessment process and is an important component of dose–response analysis and interpretation of causal associations in epidemiology studies. Exposure assessment describes the nature, magnitude, duration, and extent to which various populations are exposed to a chemical agent. There are several factors to consider when conducting an exposure assessment, such as contaminated media, route of exposure, timing of exposure (duration, frequency), and bioavailability. This chapter will review the general principles of exposure assessment, as well as methods and available tools for evaluating exposures from different media (air, soil, water, food) and different routes of exposure (dermal, oral, inhalation). Additionally, this chapter will review different methods for quantifying exposures, whether through direct measurement, historical reconstruction, modeling, or biomarkers/biomonitoring. Methods for quantifying variability and uncertainty in the exposure assessment through modeling and sensitivity analyses are also discussed. The field of exposure assessment has made significant advancements over the last several decades. The chapter will end on reflections of several lessons learned over the evolution of exposure assessment and insights for its future.