Environment

Urban particulate matter (PM) is one of many pollutants that contribute to reduced air quality in Canada. Evidence suggests that there is no safe level of exposure to PM and that PM is not limited to urban areas.¹ Concentrations of PM are caused by both human activities and natural occurrences.

Exposure to these particles can cause a range of health problems, including aggravated cardiac and respiratory diseases such as asthma, bronchitis, emphysema, and various forms of heart disease.² Children, the elderly, and people with respiratory disorders are particularly susceptible. Other toxic air pollutants can bind to the PM that is already in the air, creating additional health risks. PM exposure is a hazard for urban and rural Canadians and can affect any region of Canada year-round.

PM can also harm vegetation, materials, and buildings. When PM is deposited on metals, wood, stone, painted surfaces, and fabrics, it may cause soiling and discoloration, in addition to physical and chemical degradation of these materials. PM may also accumulate on plant surfaces and leach into soils, increasing a plant’s susceptibility to disease.³

PM, along with other air pollutants, contributes to reduced visibility and regional haze.⁴

Canada ranks 7^th out of 17 OECD countries and earns a “B” grade for urban PM₁₀ concentration. Five western European countries, along with Australia, have lower urban particulate concentration. Norway was the best performer in this category, with an urban PM₁₀ concentration of 11.5 in 2004. Canada’s urban PM₁₀ concentration was 1.7 times greater than Norway’s, at 19.1. The poorest performers were Japan, the Netherlands, and Austria, who earned “D”s for urban PM₁₀ concentrations that were almost three times that of the best performer.

Canada has reduced its PM₁₀ concentration by a modest 24 per cent since 1990. This year’s top performer, Norway, reduced urban PM₁₀ concentration by 52 per cent between 1990 and 2004. The U.K. reduced its concentration by 41 per cent.

Use the drop-down menu to compare the change in Canada’s PM₁₀ concentration with that of its peer countries.

Despite a reduction in PM10 concentration, Canada has maintained its “B” grade because other countries have made more progress. Norway’s reductions bumped it up from a “B” in the 1990s to an “A” in the most recent decade. The U.K. also moved up to an “A.” Austria, Japan, and the Netherlands are laggards on this indicator, maintaining a “D.” The U.S. has higher absolute levels of urban PM10 concentration, but its progress mirrors that of Canada. Between 1990 and 2004, the U.S. decreased concentrations by 24 per cent, maintaining its “B” grade.

A considerable proportion of PM concentration is the result of human activities, including mineral dust due to mining and extraction, windblown agricultural soil, VOCs from vehicles, industrial processes and solvents, sulphates and nitrates from power plants and transportation sources, and road and construction dust.⁵ Natural emissions of PM include wildfires, windblown dust, sea salt spray, some mineral particles, natural nitrogen oxide (NO_X), and some VOC emissions.

PM₁₀ refers to particulate matter that is 10 micrograms per cubic metre or less in diameter. PM₁₀ is generally subdivided into a fine fraction of particles 2.5 micrograms per cubic metre or less (PM_2.5) and a coarse fraction of particles larger than 2.5 micrograms per cubic metre. PM₁₀ are referred to as “inhalable coarse particles” and are found near roadways and dusty industries.

PM_2.5 are “fine particles” found in smoke and haze and can be directly emitted from sources such as forest fires. They also form when gases emitted from power plants, industries, and automobiles react in the air.⁶

So far, legislators have focused on reducing PM_2.5 concentration. In June 2000, the federal, provincial, and territorial governments, except Quebec, signed the Canada-Wide Standards for Particulate Matter (PM) and Ozone, committing them to significantly reducing PM_2.5 by 2010. Because air quality varies by region, each jurisdiction is required to create a unique implementation plan to reduce particulate matter concentration. The standards for PM are as follows:

• To achieve a Canada-wide standard for PM_2.5 of 30 micrograms per cubic metre, 24-hour averaging time, by the year 2010.
• To base the achievement on the 98^th percentile ambient measurement annually, averaged over three consecutive years.

Between 2003 and 2005, most places with PM_2.5 levels above or approaching (within 10 per cent of) the 2010 Canada-wide standard were in southern Ontario. Outside Ontario, only two communities in the B.C. Interior had levels above the standard, and none was within 10 per cent of it.⁷

Standards have yet to be created for PM₁₀. The current PM_2.5 standards, however, are an important first step toward the long-term goal of minimizing the risks of pollutants to human health and the environment. According to the Canadian Council of Ministers of the Environment, the PM_2.5 standards represent a balance between achieving the best health and environmental protection possible and the feasibility and costs of reducing the pollutant emissions that contribute to PM and ground-level ozone in ambient air.⁸

In Canada, sources of PM₁₀ emissions can be broken down as follows:⁹

• industrial sources, 42 per cent—including the coal industry, pulp and paper industry, non-ferrous mining and smelting, iron and steel production, wood industry, and mining and quarrying
• forest fires, 28 per cent
• non-industrial fuel combustion, 15 per cent—including commercial and residential fuel combustion, residential woodstoves and fireplaces, and electric power generation
• transportation, 11 per cent—including gasoline and diesel vehicles and trucks, propane-powered vehicles, railroads, marine craft, aircraft, and tire wear
• incineration, 2 per cent—including wood waste and other types of incineration.
• miscellaneous sources, 2 per cent—including building fires, pesticides and fertilizer application, cigarette smoking, and the marine cargo handling industry

¹ Environment Canada, Major Pollutants, April 30, 2002, [online, cited August 19, 2008].

² Environment Canada, Particulate Matter, September 8, 2006, [online, cited August 19, 2008].

³ Environment Canada, Major Pollutants, April 30, 2002, [online, cited August 19, 2008].

⁴ Health Canada, National Ambient Air Quality Objectives For Particulate Matter—Executive Summary, December 9, 2007, [online, cited August 19, 2008].

⁵Caitlin Hancey, Particulate Matter, Ground-Level Ozone, and the Canada-Wide Standards Regulatory Process, December 1999, [online, cited August 19, 2008].

⁶ U.S. Environmental Protection Agency, Particulate Matter, June 12, 2007, [online, cited August 19, 2008].

⁷ Canadian Council of Ministers of the Environment, Canada-wide Standards for Particulate Matter and Ozone: Five Year Report: 2000–2005 (Ottawa: Canadian Council of Ministers of the Environment, November 2006), p. 5.

⁸ Canadian Council of Ministers of the Environment, Particulate Matter & Ground-level Ozone, April 2008, [online, cited August 19, 2008].

⁹ Health Canada, National Ambient Air Quality Objectives For Particulate Matter—Executive Summary, December 9, 2007, [online, cited August 19, 2008].

See discussions on other indicators
Urban NO2 concentration	Forest cover change
Urban SO2 concentration	Organic farming
VOC emissions	Use of forest resources
Urban PM10	Marine Trophic Index
Municipal waste generation	GHG emissions
Water Quality Index	Low-emitting electricity production
Water consumption	Energy intensity
Threatened species