Population based dose models for multimedia chemicals with the potential for long range transport, May 2000
This paper is a comparison of methods for characterizing the population-based potential dose to a persistent organic pollutant with the potential for long range transport. If a chemical travels long distances in the environment, more people are exposed to the chemical increasing the potential adverse effects, owing both to the increased number of exposed individuals and to variability in individual susceptibility. Thus a method for calculating the population-based potential dose would be useful for regulators comparing the impact between various chemical emissions. It is unclear what spatial scale and model configuration should be used when calculating the population-based potential dose. Several conceptual models for population-based potential dose are presented and compared. Dose calculations are integrated with the characteristic travel distance of the chemical and population density to determine appropriate methods for evaluating population-based potential dose. A comprehensive multimedia, multipathway exposure model is used to calculate the dose per person. Case studies are presented to illustrate the differences between various calculation methods. We found that if a chemical has a long characteristic travel distance in the environment, it is important to consider exposure to individuals far from the source region when making decisions about the potential hazards from a pollutant.