Ambient Air Quality and Human Health: Current Concepts, Part 2

Abstract

This second of two parts continues with the development of a framework for understanding air quality issues and their relationship to human health. Recognized health effects associated with air pollution are described and current controversies regarding ozone and PM₁₀ are briefly outlined. Epidemiological methods of investigating air quality effects are discussed, comparing recent landmark studies in Canada. Comparative prevalence studies do not reflect the state of the art in air pollution epidemiology but are frequently cited and conducted in Canada as if they were definitive. The implications of setting air quality standards and objectives on this basis or to meet arbitrary levels of risk of health effects are examined. The current state of the art does not support risk-based air quality standards. A policy of continuous improvement is most protective of both human health and the environment.