Use of probabilistic exposure models in the assessment of dietary exposure to chemicals.

This paper provides an introduction and overview of the use of probabilistic exposure assessments (PEAs) to characterize exposures to chemicals from the diet. The paper presents: 1) the concepts of uncertainty and variability with regard to dietary exposures; 2) the risk management needs that drive the use of probabilistic models; 3) the history of the development and use of PEAs by regulatory agencies, and 4) the various types of exposure models currently in use. The models are organized based on the nature of the source of exposure that they are designed to evaluate, duration of those exposures, the complexity of the exposure pathways, and the number of variables that are treated as probabilistic. The existing guidance on performing PEAs is also reviewed and summarized. Finally, a description of potential barriers to the use of PEAs is provided with suggestions on how to remove or diminish these barriers.