Ambient Levels of Volatile Organic CompoundsFootnote [1]

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Volatile organic compounds (VOCs) are carbon-containing gases and vapours such as gasoline fumes and solvents.Footnote [2] Volatile organic compounds are emitted to air by natural sources (e.g., vegetation, forest fires), as well as from human activity (e.g., emissions from the oil and gas industry, solvent usage and transportation). Although VOC emissions from natural sources are higher during the vegetation-growing season, human activities are the main contributors of VOCs in urban areas. A number of VOCs are classified as toxic air pollutants under the Canadian Environmental Protection Act, 1999 because they can cause cancer and other serious health problems. While there are hundreds of VOC species in the outdoor air, only those that are considered important contributors to ozone formation and/or potentially toxic are routinely measured by the National Air Pollution Surveillance program.Footnote [3]

The annual average VOC concentration indicators are based on the annual average of daily VOC concentrations.

National ambient levels of volatile organic compounds

In 2013, the national annual average concentration of VOCs in the air was 59.3 parts per billion carbon (ppbC), or 4% lower than in 2012.

From 1999 to 2013, a decreasing trend of 3.7 ppbC per year was detected in VOC concentrations. This is consistent with the reduction of VOC emissions from cars and trucks, resulting from the introduction of more stringent emissions standards and reduction measures related to the production and use of solvents and paints.

Volatile organic compound concentrations, Canada, 1999 to 2013

Line chart of the national annual average concentrations of volatile organic compounds - Long description below

Long description

The line chart shows the national annual average concentrations of volatile organic compounds in the air in Canada from 1999 to 2013. A decreasing trend was detected for this time period.

Data for this chart
Volatile organic compound concentrations, Canada, 1999 to 2013
YearAnnual average concentration (parts per billion carbon)
1999120.5
2000122.2
200199.0
200291.6
2003101.6
200485.9
200587.0
200683.2
200773.1
200875.9
200973.8
201062.8
201166.6
201261.7
201359.3

Download data file (Excel/CSV; 780 B)

How this indicator was calculated

Note: The national annual average volatile organic compound concentration indicator is based on the annual average of the daily concentrations recorded at 34 monitoring stations across Canada.
Source: Environment and Climate Change Canada (2016) National Air Pollution Surveillance Program.

Regional ambient levels of volatile organic compounds

In 2013, annual average concentrations of VOCs in the air vary from 36.8 ppbC in southern Quebec to 116.6 ppbC in the Prairies and northern Ontario region. Concentrations of VOCs in 2013 were lower than in 2012 in Atlantic Canada, southern Quebec and southern Ontario and higher in the other two regions.

Decreasing trends were observed for all regions in Canada, except for Atlantic Canada where no trend was detected. From 1999 to 2013, decreasing trends of 4.1 ppbC, 3.8 ppbC, 5.4 ppbC and 4.6 ppbC per year were detected for southern Quebec, southern Ontario, the Prairies and northern Ontario region and British Columbia (Metro Vancouver), respectively.

Regional volatile organic compound concentrations, Canada, 1999 to 2013

Line chart of the annual Regional average concentrations of volatile organic compounds - Long description below

Long description

The line chart shows the annual average concentrations of volatile organic compounds from 1999 to 2013 for five regions of Canada: Atlantic Canada, southern Quebec, southern Ontario, Prairies and northern Ontario, and British Columbia. Decreasing trends were observed for all regions, except for Atlantic Canada where no trend was detected.

Data for this chart
Regional volatile organic compound concentrations, Canada, 1999 to 2013
YearAtlantic Canada annual average concentration (parts per billion carbon)Southern Quebec annual average concentration (parts per billion carbon)Southern Ontario annual average concentration (parts per billion carbon)Prairies and northern Ontario annual average concentration (parts per billion carbon)British Columbia annual average concentration (parts per billion carbon)
1999n/a91.5100.6213.9n/a
2000n/a96.096.6218.9n/a
2001132.677.771.7158.8n/a
2002103.674.466.3150.6n/a
2003148.177.872.8156.7109.5
2004110.063.461.1141.5120.1
2005117.360.661.6137.1126.0
2006123.160.859.1136.1105.5
200758.060.855.3119.9123.8
2008111.547.643.6148.088.6
2009135.042.742.4121.4111.3
201088.744.840.3109.187.0
201174.539.3n/a108.993.6
2012100.737.641.8109.269.6
201385.836.841.4116.677.7
Annual trendNo trend-4.1-3.8-5.4-4.6

Note: n/a = not available.

Download data file (Excel/CSV; 1.83 KB)

How this indicator was calculated

Note: The annual average volatile organic compound concentration indicator is based on the annual average of the daily concentrations recorded at 5 monitoring stations in Atlantic Canada, 9 in southern Quebec, 12 in southern Ontario, 5 in the Prairies and northern Ontario and 3 in British Columbia. At least three stations are required to report a concentration value for a given year. There were no values for 1999 and 2000 in Atlantic Canada and for 1999 to 2002 in British Columbia because there were only two stations with reported concentrations. For southern Ontario, no data were available for 2011.
Source: Environment and Climate Change Canada (2016) National Air Pollution Surveillance Program.

Ambient levels of volatile organic compounds at monitoring stations

The National Air Pollution Surveillance program measures air pollutant concentrations at monitoring stations across Canada. The Canadian Environmental Sustainability Indicators provide this information through an interactive indicator map. With the interactive map, you can drill down to VOC concentrations at specific monitoring stations.

Related indicators

Other information

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