Introduction - Health Effects of Air Pollution
The environmental impact of air pollutants on health, economy and quality of life has been significant the past decades. According to the World Health Organization, a study published in the Lancet in 2000, air pollution fatalities now exceed traffic fatalities by 3 to 1. In United States traffic fatalities total approximately 40,000 per year but air pollution fatalities are 70,000 per year. In Ontario, premature deaths are 1,900 per year and hospitalizations have reached 10,000 with emergency visits up to 13,000 per year. Absenteeism of 47 million lost working days in Ontario due to the health effects of air pollutants. (Ontario Ministry of the Environment, 2004). The cost of smog in Ontario on Health alone is $1 billion per year in hospital admissions, emergency visits and absenteeism.
Ground-level ozone, smog, has a significant impact on health, agriculture and economy. Chemical toxics of Carbon monoxide (CO), Nitrogen Dioxide (NO2), Sulphur Dioxide (SO2), Suspended Particulates (PM10), Nitrogen Dioxide (NO2), Nitrogen oxides (NOx) one of the leading causes of ground level ozone, dioxins, PAHs, benzene and 1.3 butadiene have contributed to respiratory problems, coronary and cardiovascular disease, cancer and premature death. There are 383 carcinogens in our environment , 5 of which cause irreversible mutations in DNA. Air pollutants originate from the combustion of fossil fuels and gasoline- powered automobiles. Traffic has been the main source of pollution in cities with high congestion. Particulates are emitted primarily from diesel engines.
There is no longer a "safe" level of pollution; it has become tolerable according to the degree and type of chemicals in the course of exposure to them over the years. The threshold of tolerance may be increased but the continuous bioaccumulation of carcinogenic and neurotoxic chemicals in organisms, together with the potential synergistic effect these chemicals have, can become fatal. The synergistic effect of chemicals is more potent than the individual parts, thus increasing susceptibility to disease on human health. Bioaccumulation depends on the concentration of chemicals in our environment and the time the organism takes to ingest, store or excrete these substances. When exposure to a specific chemical stops, the organism will gradually metabolize and excrete it.
Board of Health, Toronto, Ontario - 27 January 2003