Outdoor air pollution and health: Overview

On this page

• About outdoor air pollution
• Health impacts of air pollution overall in Canada
• Health impacts of traffic-related air pollution
• Health impacts of wildfire smoke-related air pollution
• Contact us

About outdoor air pollution

Outdoor air pollution comes from a variety of sources, and even at low levels, has an impact on human health. It leads to disease, increased hospitalizations and even premature death.

Outdoor air pollution is a complex mixture of substances, including:

• smog
• ozone
• sulphur oxides
• nitrogen oxides
• particulate matter (PM)
• volatile organic compounds (VOCs)
• polycyclic aromatic hydrocarbons (PAHs)

Most people in Canada are exposed to air pollution every day while inside and outside their homes. Even though air pollution levels are low in Canada compared to those in other countries, addressing issues of air quality remains a priority for us.

You can take action to reduce air pollution in your community. Learn more about how you can help make the air cleaner and healthier for everyone.  

Air quality modeling is a mathematical simulation of how air pollutants disperse and react in the atmosphere to affect outdoor air quality. We use air quality modeling to:

• forecast air quality
• simulate hourly levels of air pollutants over North America
• support air quality regulations and management decisions for Canada

Health impacts of air pollution overall in Canada

We estimate that every year in Canada, air pollution is linked to:

• 15,300 premature deaths 
• 2.7 million asthma symptom days 
• 35 million acute respiratory symptom days 

We estimate the socio-economic costs of the health impacts of air pollution in Canada at $120B per year (based on 2016 currency).

Our analysis uses the best available health and air quality data for Canada.

We determine ambient levels of the pollutants using:

• ground measurements
• satellite measurements
• air quality computer models

We estimate the exposure to air pollution in Canada by combining air pollution and population distribution maps. We use mathematical equations for associations between air pollution and health effects to estimate the:

• number of premature deaths (and other health outcomes) in Canada
• socio-economic costs of the air pollution health impacts in Canada

This method is similar to those used by other health organizations, both in Canada and internationally.

You can download a technical report on the health impacts of air pollution in Canada.

Health impacts of traffic-related air pollution

We estimate that every year in Canada, traffic-related air pollution contributes to:

• 1,200 premature deaths
• 210,000 asthma symptom days
• 2.7 million acute respiratory symptom days

We estimate the cost of health impacts of traffic-related air pollution at $9.5B per year, based on 2015 currency.

Approximately four out of ten Canadians live within 250 m of a high traffic roadway, (includes expressways, highways, arterial roads, and major roads). A high traffic roadway is an area that is associated with a higher risk of exposure to traffic related air pollution, putting those living close to them at greater risk of adverse health effects. Among those Canadians residing near high traffic roadways, many are from vulnerable populations (children, elderly and lower socioeconomic groups) who may be at greater risk than the general population of experiencing adverse health effects from exposure to air pollution.

*From the 2022 reports: Health impacts of traffic-related air pollution in Canada; Exposure to traffic-related air pollution in Canada: An assessment of population proximity to roadways; and Traffic-Related Air Pollution: An Umbrella Review-Based Human Health Risk Assessment on Selected Cancer Types.

Health impacts of wildfire smoke-related air pollution

We estimate that in recent years in Canada, air pollution from wildfire smoke contributed to:

• several hundred to several thousand premature deaths annually
  • these numbers vary with the severity, intensity and location of the wildfires
• many asthma episodes, hospital admissions for heart and respiratory problems, and other health outcomes 

We estimate the annual cost of the Canadian health impacts of wildfire smoke-related air pollution $5 billion to $21 billion.

Contact us

For more information on air pollution, please contact us:

Email: air@hc-sc.gc.ca
Telephone: 1-833-223-1014 (toll free)

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