INHALED PARTICLE DOSIMETRY: Session Commentary.

The Third Colloquium on Particulate Matter and Human Health addressed the roles that inhaled particle dosimetry plays in understanding the potential health risks of human populations exposed to particulate air pollution. Nineteen papers, including posters, were presented that addressed particle deposition and clearance in both humans and laboratory animals. The effects of age, gender, and illness were addressed, as well as ultrafine particles and correlations between particle deposits and tissue pathology. The papers and related discussions also illuminated some important gaps in knowledge, such as the accuracy of dosimetry predictions for individuals; the underrepresentation of susceptible populations; the movement of deposited particles to nonlung tissues and organs; and the accuracy of extrapolations across species. Although current dosimetric information is useful for understanding the effects of particulate air pollution, several unsolved problems remain. [ABSTRACT FROM AUTHOR]