Air Pollution and Health and the Role of Aerosols

Particulate matter air pollution is probably the most significant environmental hazard to human health in developed countries. Particles, present in the atmosphere as aerosols, enter the respiratory tract having a limited capability of handling the load, and are associated with large range of serious diseases from cardiovascular conditions to inflammation and to lung cancer. Particle size is an important determinant of the particle behavior in the respiratory tract. Currently the strongest evidence on the health effects is obtained with ambient epidemiology associating outdoor mass concentrations with various health outcomes. Current research shows no safe level below which particulate air pollution does not cause any adverse health effects. Epidemiological studies have shown that those with existing cardiovascular or respiratory disease are more susceptible to exposures to air pollution. However, in practice the health effects on an individual level are caused by exposures, and further, by particle doses depositedI would avoid the translocation theme in the lung. Nevertheless, the current practice is to use concentration-response functions to characterize the risks. Further research is needed to transform these relationships towards dose-response and for accounting alternative descriptors of the doses, such as particle number and particle surface area.