Dependence of Intake Fraction on Release Location in a Multi-media Framework: A Case Study of Four Contaminants in North America

摘要

Given the range of possible pathways for human exposure and the large number of industrial, agricultural and consumer activities that release chemicals into the environment, simplified methods are needed to assess different scenarios and to identify the combinations of chemical, environmental and population characteristics that lead to elevated exposures. Models of the environmental fate of chemical contaminants and subsequent human exposure have therefore found a variety of scientific and regulatory applications. These include screening level environmental fate assessments, comparative risk assessment of chemicals, and life cycle impact assessments of product or process alternatives. Screening assessments often use intake of chemical as a convenient metric of potential dose of contaminant received by a population. The population-based intake of an environmental contaminant depends on (1) the receiving media for the emission and the multi-media fate and transport of the chemical in the environment, (2) the relationship between contaminant concentration in environmental media and exposure media and (3) the rate at which the population contacts the exposure media through multiple exposure pathways.