One of the great challenges in environmental medicine is to define more accurately the adverse health effects likely to be encountered by exposures to these pollutants, since reducing exposure to zero is not politically and economically achievable. For many common pollutants, accurate extrapolations from animal toxicology studies to humans and from short-term to long-term chronic effects are essential. Extrapolation models which can be verified and have characteristics that can be generalized across classes of pollutants offer the only feasible approach for obtaining the data needed to assess effects of large number of pollutants in the environment. Physical testing of the acute and chronic effects in multiple animal species for large numbers of different pollutants is not an economically realistic approach. The conference has focused on oxidant air pollutants and modeling of the respiratory system. These are areas in which some of the most extensive data bases exist in the relatively young field of extrapolation modeling. The successful development of effective new models requires a combined input from creative investigators in a broad number of fields. One of the primary purposes of the conference was to assemble these types of investigators in a forum that could focus future research efforts in areas of common interest and facilitate the development and testing of better extrapolation models.

"Presented at the Proceedings of Extrapolation of Dosimetric Relationships for Inhaled Particles and Gases, J.D. Crapo, J.A. Graham, F.J. Miller, A.W. Hayes, editors, Academic Press." "EPA/600/D-89/143." Microfiche.