ABSTRACT
Demographics is the statistical study of human populations with respect to size, density, distribution, and vital statistics. In an exposure assessment, the analyst will typically specify the particular population of interest in terms of such demographic characteristics as residential location, housing characteristics, age, gender, work status, proximity to sources, and lifestyle. This chapter provides an introduction to the demographic data and its use in exposure assessments. Each exposure event describes conditions affecting a person’s exposure for a specified time interval. The exposure event may assign an individual to a geographic location, a housing type, a microenvironment, and an activity. The population of concern in a risk assessment can vary in size from a cluster of homes drawing water from a single well to the entire population of the United States. In either case, the analyst must determine which demographic characteristics are required to perform the risk assessment and identify reliable databases that can be used as sources for this information.
