Issued also in French under title: Indicateurs canadiens de durabilité de l'environnement : qualité de l'air.

Includes bibliographical references (page 70).

Air quality problems such as smog and acid rain result from the release of pollutants into the atmosphere. The majority of these pollutants come from human activities, such as transportation, the burning of fuels for electricity and heating, and industry. Pollutants from natural sources, such as wildfires, can sometimes be substantial. Air pollutants cause adverse health and environmental effects. The Air quality indicators present the concentrations of 5 key air pollutants for Canada.