Urban air pollution is made up of a complex mix of hundreds of substances including toxic air pollutants and criteria air contaminants such as nitrogen oxides (NOx), sulphur oxides (SOx), ozone (O3) and particulate matter (PM). Air pollution can cause heart and breathing problems, affect birth outcomes, brain development and function, and is linked to cancer, chronic diseases (including diabetes), and other illnesses. Air pollution can affect people differently, and some people are more vulnerable to the health effects from air pollution. Reducing air pollution can result in better health outcomes for everyone.
The air pollutants found in Toronto are mainly the by-products of burning fossil fuels. When we burn gasoline, diesel fuel, natural gas and coal in our cars, trucks, home furnaces, industries and power plants, we send pollutants into the air. Traffic-related air pollution (TRAP) is the largest local source of air pollution in Toronto, followed by emissions from industrial and residential sources. Toronto’s air pollution comes from local sources in Toronto and from beyond, and air pollution from Toronto can affect other communities.
In the past, smog and smog advisories were common for Toronto. Smog is a mixture of pollutants in the air that can affect our health and the environment. It sometimes appears as a brownish haze. Smog is made up of ground-level ozone, fine particles and other pollutants. Smog can occur any time of year, but it is most common in the summer. Smog can affect outlying suburbs and rural areas as well as big cities.
Thankfully, Toronto has not experienced a smog advisory since 2016. However, the persistence of air pollution means that smog remains a possibility in Toronto.
The TPH report Path to Healthier Air: Toronto Air Pollution Burden of Illness Update identified that Toronto is on a path to healthier air, but that more work needs to be done to ensure ongoing improvement in the City’s air quality.
The report found that:
Read the report to learn more about the health impacts from air pollution in Toronto.
Toronto Public Health works collaboratively with other City divisions in addressing air quality issues like wildfire smoke in order to protect the health of people in Toronto.
Find out more about some of these initiatives below.
The TransformTO Net Zero Strategy aims to reduce community-wide greenhouse gas (GHG) emissions to net zero by 2040. The City’s 2040 net zero target is one of the most ambitious in North America.
Learn more about the TransformTO Net Zero Strategy.
Traffic related air pollution (TRAP) is the largest local source of air pollution in Toronto. The TPH report Avoiding the TRAP: Traffic Related Air Pollution in Toronto and Options for Reducing Exposure identifies a number of strategies that can effectively mitigate exposure to traffic pollutants for people in Toronto.
Read the report to learn more about reducing traffic related air pollution in Toronto.
Idling gets us nowhere. Exhaust emissions from cars, trucks and other vehicles are a major source of air pollution in Toronto. Running your engine while parked for more than 60 seconds is prohibited under City of Toronto By Law 517.
Most heating, ventilation and air conditioning (HVAC) systems draw fresh air from outdoors. So, it may not be possible to completely prevent outdoor air and air pollution from entering your home. Still, there are actions that people can take to reduce the amount of outdoor air pollutants entering their home:
Other measures to keep indoor air clean:
If unable to get relief from air pollution including wildfire smoke at home, people can go to a public facility with air conditioning like a library, recreation centre or shopping mall.
People are encouraged to visit the AQHI health guide to evaluate their sensitivity to air pollution. Learn more about the AQHI below.
Everyone can take meaningful steps to reduce their own contributions to air pollution:
Learn more about what you can do to reduce emissions.
The Government of Canada and the Ontario Ministry of the Environment, Conservation and Parks (MECP) will jointly release air quality alerts like a Special Air Quality Statement (SAQS) or a Smog Air Health Advisory (SAHA) when the Air Quality Health Index (AQHI) is forecast to be high. People can sign up to receive air quality alert email notifications on the MECP webpage.
Visit the Ministry of the Environment, Conservation and Parks webpage to learn more about SAQS and SAHA. See below to learn about the Air Quality Health Index (AQHI).