Air pollution: drivers and impacts

Air pollutionFootnote 1 can affect Canadians' health, the environment, buildings, structures and the economy. Air pollution problems such as smogFootnote 2 and acid rain result from the presence of and interactions between various pollutants released to the atmosphere through natural processes and human activities.

Natural sources of air pollution include forest fires, volcanoes and emissions of volatile organic compounds (VOCs) from vegetation. Human sources of air pollution include activities that rely on carbon-based fuels (for example, transportation, off-road vehicles and mobile equipment, electric utilities), industrial processes such as oil and gas production, as well as certain products, such as paints and solvents.

Key drivers of air pollution

Outdoor air pollutant concentrations can be influenced by many factors. These include the quantity of air pollutants released by sources, the distance from the sources, and meteorological conditions such as air temperature, the stability of the air, wind speed and direction. Some air pollutants can be carried by the wind and affect the air quality in locations which are hundreds to thousands of kilometres away from the sources.

The growth in Canada's population and economy increases the demand for the production and delivery of goods and services, transportation and housing. Most of the energy used to meet this demand still comes from fossil fuels, which impacts the quality of the air we breathe. Economic growth includes a growing demand for Canadian exports (especially from the oil and gas industry) that also results in releases of air pollutants.

Despite this growth in demand, the quantity of emissions of many air pollutants has generally decreased in Canada in the past two decades. These reductions were achieved through various means, including the implementation of regulations, non-regulatory instruments, and technological improvements for transportation vehicles and industrial processes. The adoption of more environmentally sustainable practices by consumers and industry, such as using public transit and carpooling, and optimizing production processes to reduce energy use, have also contributed to the decrease.

Consult the Air pollutant emissions indicators for more information on the main sources contributing to Canada's emissions of key air pollutants: sulphur oxides (SOX), nitrogen oxides (NOX), volatile organic compounds (VOCs), ammonia (NH3), carbon monoxide (CO) and fine particulate matter (PM2.5).

Key impacts of air pollution

Human health impacts

Environmental impacts

Economic impacts

Ways to tackle air pollution

Air pollution is a global issue that affects everyone and that results from decisions and actions taken by individuals and government. We all have a part to play in reducing it. 


Releasing pollutants into the atmosphere is subject to a number of regulations in Canada. Specifically, the Government of Canada, under the authority of the Canadian Environmental Protection Act, 1999 (the act) develops and implements regulations to help reduce overall levels of air pollution by limiting the amount of pollutants that are released into the air each year.

For example, the Government of Canada has put in place regulations to phase out coal-fired electricity, adopted the most stringent national standards in the world for air pollutant emissions from new cars and light trucks and put a price on carbon pollution that is creating incentives for industry to invest in cleaner technologies.

In 2016, as part of the federal government's contribution to the implementation of the Air Quality Management System, the Government of Canada introduced the Multi-sector Air Pollutants Regulations. This is Canada's first ever mandatory national air pollutant emissions standards for major industrial facilities. The federal government also published a suite of non-regulatory instruments to reduce air pollutants from a number of industrial sectors and equipment types. The Government of Canada continues to work with provinces, territories and stakeholders to set more stringent Canadian Ambient Air Quality Standards (CAAQS, the standards) to drive air quality improvements across the country. More stringent standards for PM2.5 and O3 have been in effect since 2015 and 2020, respectively. A new standard for ozone will come into effect in 2025 (it was established in 2019). Standards for sulphur dioxide (SO2) and nitrogen dioxide (NO2) were established in 2017 for 2020 and 2025. The PM2.5 standard is currently under review. The regulations and standards will contribute to reducing emissions of air pollutants and further protect human health and the environment for Canadians.

Regulations specific to air pollutants under the Canadian Environmental Protection Act, 1999 include, but are not limited to, the following:

All regulations administered under the act are available in the Canadian Environmental Protection Act Registry.

To learn more about the expected impact of regulations developed by the Government of Canada, consult the Regulatory Impact Analysis StatementFootnote 13  that accompanies each regulation. The statements outline the reasoning behind the development of a particular regulation, its objectives, and its expected costs and benefits. They also include details about consultations that were conducted and about how the government intends to track the performance of the regulation. 

In addition to the above, the Government of Canada in collaboration with partners within Canada and internationally, develops the Federal Sustainable Development Strategy. The Strategy is the Government's primary vehicle for sustainable development planning and reporting. It sets out sustainable development priorities, establishes goals and targets, and identifies actions to achieve them, including actions related to tackling air pollution. Bilateral and international cooperation, including under the Canada-United States Air Quality Agreement and the United Nations Economic Commission for Europe’s Convention on Long-range Transboundary Air Pollution, is also an important component of Canada’s approach for improving air quality and key to advancing Canada’s air quality objectives.


Below are some actions you can take to help reduce overall air pollution levels:

For more tips on what you can do, visit What you can do to improve air quality.

To reduce your exposure to air pollution and its potential health effects, you can:

Related indicators

The Air health trends indicator  provides an overview of the public health impacts attributable to outdoor air pollution in Canada.

The Air quality indicators track ambient concentrations of fine particulate matter (PM2.5), ozone (O3), sulphur dioxide (SO2), nitrogen dioxide (NO2), and volatile organic compounds (VOCs) at the national and regional levels and at local monitoring stations. 

The International comparison of urban air quality indicators present and compare the air quality in selected Canadian urban areas with a population greater than one million to the air quality in selected international urban areas having comparable data.

The Air pollutant emissions indicators track emissions from human activities of 6 key air pollutants: sulphur oxides (SOX), nitrogen oxides (NOX), volatile organic compounds (VOCs), ammonia (NH3), carbon monoxide (CO) and fine particulate matter (PM2.5). Black carbon, which is a component of PM2.5, is also reported. For each air pollutant, data are provided at the national, provincial/territorial and facility level and by major source. 

The International comparison: air pollutant emissions in selected countries indicators compare Canada's emissions of 5 key air pollutants with those of top emitting member countries of the Organisation for Economic Co-operation and Development (OECD). 

The Human exposure to harmful substances indicators ttrack the concentrations of 4 substances (mercury, lead, cadmium and bisphenol A) in Canadians.Footnote 14

The Emissions of harmful substances to air indicators track human-related emissions to air of 3 toxic substances, namely mercury, lead and cadmium, and their compounds. For each substance, data are provided at the national, provincial/territorial and facility level and by source. Global emissions to air are also provided for mercury. 

The Population exposure to outdoor air pollutants indicator tracks the proportion of the Canadian population living in areas where outdoor concentrations of air pollutants are less than or equal to the 2020 Canadian Air Ambient Quality Standards.

Other information

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