Exposure analysis and assessment for low-risk cancer agents.

The analysis of exposure is a necessary feature of epidemiological studies. In the case of low-risk cancer agents, the examination of potential exposure should follow a sequence that prioritizes the major media and routes of concern. This will minimize the misclassification of exposure and the failure to identify important co-factors, e.g. contamination in other media, etc. The manuscript describes specific components of exposure analysis and provides examples that pertain to single and multimedia exposure problems. The approach is examined by using the Total Human Environmental Exposure Study (THEES) for benzo(a)pyrene as a potential model for low-risk cancer agents. Since benzo(a)pyrene can be found in air, water, soil and food, and has a number of sources, THEES illustrates how to prioritize an exposure assessment, take advantage of opportunities to conduct micro-environmental measurements, and collect personal monitoring and biological marker samples. A daily activity log is briefly described.