Interim Plan 2001 on Particulate Matter and Ozone: chapter 1

1.0 Introduction

Air pollution is one of the top environmental issues, and public health officials have expressed a growing concern over its impacts on the population. Recent statistics show air pollution causes an estimated 5,000 premature deaths in Canada each year, and thousands more suffer from adverse health effects.

Air pollution has been a problem since the industrial age began, but only recently has the real extent of its impact on human health been understood, with a link between two key elements of smog (particulate matter and ozone) and premature deaths and respiratory ailments.

Significant progress has been made in reducing air pollutants in some key areas. However, challenges remain in controlling major sources of pollution, in providing information so that Canadians can make responsible decisions, and in acquiring a better understanding of the health risks.

The federal strategy on clean air brings together science, actions on emissions and outreach. In this way, the measures and actions to control emissions are backed by science, we understand as much as possible about the effects on health, and we reach out to Canadians through a coordinated partnership process.

Air Issues Management in Canada

Jurisdiction for environmental management in Canada is shared among the federal government, provinces and territories. These governments work together under the Canadian Council of Ministers of the Environment (CCME) and the Canada-wide Accord on Environmental Harmonization.

The Government of Canada's role in air issues is:

Jurisdictions that signed the Canada-wide Standards for Particulate Matter (PM) and Ozone in June 2000 made a commitment at that time to set out an implementation plan for meeting the standards. Like other agreements on Canada-wide Standards (CWS), this plan is based on the principle that responsibility and actions will be assumed by the best-situated order of government.

As this federal plan is the first to set out a series of commitments, initiatives and actions under this particular CWS process, it has been designated as an interim plan. Regular updates will reflect progress, new initiatives and the ongoing consultations and coordination with provincial and territorial partners on commitments in their jurisdictions.

Canada has many regions where air quality is better than the levels set out in the CWS. However, there is still no apparent lower threshold for health effects. Therefore, we will continue to implement practicable pollution prevention and best management practices that have been identified as the best course of action by the Government of Canada and other jurisdictions.

Smog in Canada

Smog is often perceived as dirty or hazy air, most often in the warm summer months. Smog not only reduces visibility, it also affects health.

Extensive studies indicate there are significant health and environmental effects associated with PM and ozone. Epidemiological and human exposure studies show that as ozone levels rise, adverse health symptoms increase. Field and controlled human exposure studies have indicated that patients with pre-existing respiratory diseases (e.g., asthma) are more susceptible to ozone-induced health effects, and that exercise makes these effects even more noticeable. The smallest particles, PM2.5, have potential for the greatest health impact on a larger segment of the general population.

Elevated concentrations of PM are found year-round in all regions of Canada, while ground-level ozone is a summertime regional problem. Exposure to elevated levels of ozone is most frequent in the Windsor-Quebec City corridor of Ontario and Quebec, the southern Atlantic region of southern New Brunswick and southwestern Nova Scotia, and the Lower Fraser Valley of British Columbia.

What is Smog?

Smog consists primarily of ozone and particulate matter (PM) in ambient air. Ozone is a gas formed in sunlight and warm, stagnant air, from the precursor gases of nitrogen oxides (NOX) and volatile organic compounds (VOC).

VOC + NOX + Heat + Sunlight = Ozone

PM is tiny solids or liquid droplets released either directly into the air from a variety of sources such as cars, trucks, factories, construction sites, agriculture, unpaved roads, stone crushing, and burning of wood, or formed in the air from the chemical change of gases. PM is indirectly formed when gases from burning fuels react with sunlight and water vapour.These gases can result from fuel combustion in motor vehicles, at power plants, and in other industrial processes.

Generalized Chemical Composition of Ambient PM

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