20 - The Epidemiologic Approach to Investigating Outdoor Air Pollution

Abstract

Epidemiology will remain an important research method for addressing the health effects of air pollution. It provides evidence directly from human population that is complementary to the findings of toxicologic studies. This chapter discusses epidemiologic approach for investigating the health effects of outdoor air pollution. Epidemiology comprises the scientific methods used to study disease occurrence in human populations, including description of the occurrence of disease and identification of the causes of disease. Epidemiologic studies address the effects of inhaled pollutants as exposure occurs in the community. Their results can document the occurrence of adverse effects of air pollution and describe the relationship between exposure and response, and characterize effects on susceptible groups within the population, for example, persons with asthma. In general, epidemiologic studies are carried out with several objectives: to determine if air pollution or a source of air pollution poses a hazard to human health; to characterize the relationship between the level of exposure and the response; and to examine responses of potentially susceptible populations to pollutant exposures. Although epidemiologic studies are subject to potentially limiting methodologic problems, new approaches for assessing exposure to pollutants and health outcomes should strengthen the epidemiologic approach for investigating the health effects of air pollution.