Air Pollution Sources in Ontario

The following charts illustrate the sources of nitrogren oxides (nitrogen oxides (NO_x), sulphur dioxide (SO₂), volatile organic compounds (VOCs) and particulate matter (PM) - four of the key precursors to smog in Ontario – as well as sources of greenhouse gas (GHG) emissions in Ontario.

The electricity sector in Ontario accounts for 15% of Ontario’s NO_x emissions, 25% of SO₂ emissions and 11% of GHG emissions.

Transportation, a mobile source of emissions, accounts for 64% of NOx emissions, 29% of VOC emissions, 10% of PM emissions and 27% of GHG emissions.

Source for air pollutant data: Ontario’s Clean Air Action Plan: Protecting Environmental and Human Health in Ontario http://www.ene.gov.on.ca/programs/4708e.htm

Source for greenhouse gas emission data: Canada’s Emissions Outlook: An Update, Natural Resources Canada, December 1999 http://www.nrcan.gc.ca/es/ceo/update.htm