Particle deposition and clearance from the respiratory tract

Abstract

Epidemiological studies have repeatedly associated high levels of ambient particulate matter with increased hospital admission and daily mortality. The adverse health effects have especially been linked to fine and ultra fines (<0.1μm) from combustion sources. Despite the fact that hazardous exposure to ultra fine particulates has clearly been reported, it is still under investigation which exact particle characteristics underlie the health effects. The rapid growing field of nanotechnology might be another source of exposure to potential harmful nano sized particulates. Better understanding of the particle characteristics that are related to adverse effects will help in addressing regulation strategies. In this thesis I will explain how regional particle deposition in the respiratory tract and clearance mechanisms are influenced by physical and chemical particle properties such as particle size, density and shape. Moreover I show how particle deposition site and particle clearance mechanisms are related to pulmonary and extra-pulmonary health effects.