ABSTRACT
The distribution of chemical pollutants throughout the various environmental compartments is the result of complex physical, chemical, and biological processes. Human health risks related to the presence of various pollutants in the environment depend on the degree of multimedia exposure of humans to these chemicals. The assessments of risks due to the exposure of a receptor to pollutants is generally determined from appropriate dose-response relations. Pollutants move across environmental phase boundaries as the result of complex intermedia transport processes. The distribution of chemical pollutants in the environment can be estimated using appropriate mass transfer models which are based on the principle of mass conservation. It is important to realize that the main driving force in any multimedia model is the source of the chemical under consideration. Spatial models are desired when a site-specific predictive capability is required. Such models are designed to provide one-, two-, and three-dimensional spatial resolution of chemical concentration profiles.
