Environmental and occupational toxicants.

Abstract

Biological monitoring is the analysis of human biological materials for a substance of interest and/or its metabolites (biomarkers) or a biochemical change that occurs as a result of an exposure to provide a quantitative measure of exposure or dose. These measures can be used in epidemiological studies either directly as estimates of exposure or indirectly in the calibration of other exposure assessment methods, such as questionnaires. This chapter will discuss important methodological considerations for the implementation of biomarkers of exogenous exposure in epidemiology by focusing on biomarker characteristics (e.g. variability, half-life) and their application in different study designs.