Outdoor Air Pollution Environmental Exposures

Outdoor Air Pollution Environmental Exposures


Canadians are exposed to fine and ultrafine particles by breathing outdoor air containing emissions from any combustion source, including industrial processes, gasoline and diesel engine exhausts, fireplaces, furnaces, prescribed burning for forestry and agricultural purposes, and naturally-caused wildfires.[1]


Particulates in outdoor air are monitored by the National Air Pollution Surveillance (NAPS) network. In 2013, the annual average levels of PM2.5 was 7.3 µg/m3, and the annual peak 24-hour concentration was 20 µg/m3. Both of these values remained below the 2015 Canada Wide Standard.[1] Between 1985 and 2012, daily averages for PM10 remained below 10 µg/m3 in 44 of 49 different sites located across Canada. Higher levels of PM10 were found in large urban areas and near roadways.[2]

Estimates of potential lifetime excess cancer risk for outdoor air pollution are unavailable at this time.

A search of Environment Canada’s National Pollutant Release Inventory (NPRI) yielded the following results on current potential for exposure to outdoor air pollution in Canada:


NPRI 2015[3]
Substance name: ‘PM – Total Particulate Matter’
‘PM10 – Particulate Matter ≤ 10 microns’
‘PM2.5 – Particulate Matter ≤ 2.5 microns’
All amounts released into environment (on-site release)
PM Type # of facilities Quantity Industry
Total PM 1,188 327,251 t Resource extraction and processing, manufacturing
PM10 3,142 131,212 t
PM2.5 3,521 48,780 t
t = tonne


This map shows predicted levels of PM2.5 in outdoor air at residential locations in Canada in 2011. The average concentration of PM2.5 measured in outdoor air in 2011 was 6.9 µg/m3, but concentrations of PM2.5 can be higher or lower than average in many locations. 

2011 Predicted Annual Average PM2.5 Concentrations in Outdoor Air at Residential Locations

*Measured at the National Air Pollution Surveillance (NAPS) monitors in 2011
Methods and Data

Our Environmental Approach page includes documentation on our mapping methods.

Data sources and data quality for outdoor air pollution can be found in the PDF below.

Supplemental data – Outdoor Air Pollution [PDF]


1. Environment and Climate Change Canada. Ambient Levels of Fine Particulate Matter (2016)
3. Environment and Climate Change Canada. National Pollutant Release Inventory (NPRI) Facility Search (Substance name: ‘Particulate matter’)

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