Air pollutant emissions
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Air pollution problems, such as smog and acid rain, result from the release of pollutants into the atmosphere. These pollutants can affect the health of people in Canada, the environment, infrastructure and the economy. The majority of these pollutants are released through human activities, such as the burning of fuels for electricity and heating, transportation, and industrial activities. The indicators on sulphur oxides (SOX), nitrogen oxides (NOX), volatile organic compounds (VOCs), carbon monoxide (CO), ammonia (NH3) and fine particulate matter (PM2.5) and black carbon, a component of PM2.5, report emissions released through human activities.
National
National air pollutant trends
This section presents a summary of Canada's emissions of 6 key air pollutants between 1990 to 2023, highlighting the main sources and provincial and territorial distributions for 2023. Detailed analysis by pollutant, including information from industrial and commercial facilities, accessible through an interactive map, are presented following this section. Information on black carbon, a component of particulate matter, along with emissions from 3 of the largest source sectors in Canada, are presented following the indicators.
Key results
- In 2023, emissions of 5 key air pollutants were lower than in 1990:
- SOX 80% lower
- NOX 45% lower
- VOCs 38% lower
- CO 65% lower
- PM2.5 15% lower
- Emissions of NH3 were 25% higher in 2023 than in 1990
Air pollutant emissions, Canada, 1990 to 2023

Data table for the long description
Year | Sulphur oxides (percentage change from 1990 level) |
Nitrogen oxides (percentage change from 1990 level) |
Volatile organic compounds (percentage change from 1990 level) |
Ammonia (percentage change from 1990 level) |
Carbon monoxide (percentage change from 1990 level) |
Fine particulate matter (percentage change from 1990 level) |
---|---|---|---|---|---|---|
1990 | 0 | 0 | 0 | 0 | 0 | 0 |
1991 | -7 | -3 | -1 | -1 | -3 | -3 |
1992 | -11 | 0 | 0 | 2 | -3 | -5 |
1993 | -14 | 4 | 5 | 3 | -2 | -5 |
1994 | -21 | 10 | 7 | 7 | -1 | -4 |
1995 | -17 | 14 | 10 | 14 | 0 | -4 |
1996 | -16 | 17 | 13 | 18 | -2 | -6 |
1997 | -18 | 22 | 13 | 19 | -5 | -5 |
1998 | -19 | 23 | 13 | 19 | -7 | -7 |
1999 | -23 | 23 | 12 | 18 | -9 | -8 |
2000 | -23 | 20 | 11 | 20 | -11 | -9 |
2001 | -23 | 15 | 8 | 20 | -14 | -10 |
2002 | -25 | 13 | 8 | 22 | -16 | -14 |
2003 | -27 | 12 | 5 | 21 | -20 | -14 |
2004 | -27 | 5 | 2 | 25 | -26 | -16 |
2005 | -30 | 1 | 3 | 24 | -31 | -15 |
2006 | -37 | -6 | -3 | 21 | -37 | -19 |
2007 | -39 | -7 | -6 | 22 | -43 | -18 |
2008 | -45 | -10 | -10 | 20 | -46 | -16 |
2009 | -53 | -16 | -17 | 16 | -48 | -29 |
2010 | -57 | -16 | -18 | 14 | -48 | -17 |
2011 | -60 | -20 | -21 | 13 | -51 | -17 |
2012 | -61 | -25 | -20 | 17 | -53 | -14 |
2013 | -61 | -27 | -19 | 21 | -54 | -12 |
2014 | -63 | -29 | -19 | 19 | -56 | -11 |
2015 | -65 | -31 | -23 | 19 | -58 | -14 |
2016 | -65 | -35 | -28 | 19 | -58 | -18 |
2017 | -69 | -35 | -28 | 17 | -59 | -17 |
2018 | -73 | -36 | -27 | 21 | -60 | -14 |
2019 | -76 | -38 | -30 | 21 | -61 | -13 |
2020 | -78 | -44 | -38 | 25 | -65 | -21 |
2021 | -79 | -44 | -38 | 26 | -65 | -18 |
2022 | -78 | -45 | -38 | 22 | -65 | -17 |
2023 | -80 | -45 | -38 | 25 | -65 | -15 |
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How this indicator was calculated
Note: This indicator reports emissions of 6 key air pollutants from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation. Emissions from black carbon, a component of PM2.5, are also not included. Consult the black carbon section for a detailed analysis of the pollutant or the interactive figures to explore the national results and emissions from black carbon in a dynamic and customizable format.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
The years 2020 and 2021 were marked by the COVID-19 pandemic. This coincides with decreases in emissions between the years 2019 and 2020 for all the pollutants, except for NH3. In 2021, the second year of the pandemic, most of the pollutant emissions increased compared to 2020 levels but stayed below their 2019 pre-pandemic levels. The year 2023 has shown decreases in SOx, CO and NOx compared to 2022. In contrast, emissions of PM2.5, NH3, and VOCs increased between 2022 and 2023. For all pollutants except NH3, emissions in 2023 remained below 2019 pre-pandemic levels.
Air pollutant emissions by source
Key results
- In 2023, the largest sources of emissions of the 6 key air pollutants in Canada were the oil and gas industry, off-road vehicles and mobile equipment, agriculture, and dust and fires (for example, road dust, dust from construction operations and prescribed burning, but excluding forest fires)
Distribution of air pollutant emissions by source, Canada, 2023

Data table for the long description
Source | Sulphur oxides (percentage of national emissions) |
Nitrogen oxides (percentage of national emissions) |
Volatile organic compounds (percentage of national emissions) |
Ammonia (percentage of national emissions) |
Carbon monoxide (percentage of national emissions) |
Fine particulate matter (percentage of national emissions) |
---|---|---|---|---|---|---|
Oil and gas industry | 43.5 | 36.8 | 39.5 | 0.5 | 11.9 | 1.0 |
Manufacturing | 5.6 | 5.7 | 8.0 | 2.3 | 2.7 | 1.1 |
Ore and mineral industries | 27.6 | 6.9 | 0.6 | 0.3 | 11.4 | 2.3 |
Transportation (road, rail, air and marine) | 0.5 | 24.6 | 4.8 | 1.3 | 22.2 | 0.6 |
Off-road vehicles and mobile equipment | <0.1 | 13.4 | 9.3 | <0.1 | 37.9 | 1.1 |
Building heating and energy generation | 0.3 | 4.7 | 0.2 | <0.1 | 0.7 | 0.3 |
Electric utilities | 22.2 | 7.3 | 0.1 | <0.1 | 0.9 | 0.1 |
Home firewood burning | <0.1 | 0.3 | 4.6 | 0.1 | 11.7 | 3.7 |
Incineration and waste | 0.3 | 0.3 | 0.9 | 1.4 | 0.2 | <0.1 |
Paints and solvents | n/a | <0.1 | 19.8 | n/a | <0.1 | <0.1 |
Agriculture (livestock, crop production and fertilizer) | <0.1 | 0.2 | 8.3 | 93.5 | <0.1 | 25.4 |
Dust and fires | <0.1 | <0.1 | <0.1 | <0.1 | 0.3 | 63.2 |
Miscellaneous | <0.1 | <0.1 | 3.7 | 0.1 | 0.1 | 1.2 |
Note: n/a = not available. The percentages have been rounded off and their sum may not add up to 100.
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How this indicator was calculated
Note: The indicator reports emissions of 6 key air pollutants from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation. Emissions from black carbon, a component of PM2.5, are also not included. Consult the black carbon section for a detailed analysis of the pollutant. The category "dust and fires" includes emissions from human activities such as prescribed burning and dust from roads. Consult Table 1 in the Data sources and methods for a complete list of the air pollutant emissions sources included under each category.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
In 2023, the human-made sources most contributing to Canada's air pollutant emissions were the following:
- the oil and gas industry, ore and mineral industries and electric utilities together represented the majority of SOX emissions
- the oil and gas industries, transportation (road, rail, air and marine) and off-road vehicles and mobile equipment were major sources of NOX emissions
- most of the VOC emissions came from the oil and gas industry and from the use of paints and solvents
- agriculture (livestock, crop production and fertilizer) accounted for the majority of NH3 emissions
- off-road vehicles and mobile equipment, transportation, the oil and gas industry, home firewood burning and ore and mineral industries were major sources of CO emissions
- dust and fires were the largest sources of PM2.5 emissions, agriculture being the second largest source
Air pollutant emissions by province and territory
Key results
At the provincial and territorial level, emissions of the 6 key air pollutants in 2023 were:
- the highest in Alberta for SOX (27% of national emissions), NOX (42%), VOCs (35%) and NH3 (27%); second highest for CO (23%) and PM2.5 (25%)
- the highest in Quebec for CO (26%)
- the highest in Saskatchewan for PM2.5 (26%); the second highest for SOx (19%) and NH3 (22%),
- the second highest in Ontario for VOCs (20% of national emissions) and NOX (14%),
- also important
- British Columbia for NOX, accounting for 14% of the national emissions of this pollutant
- Quebec for SOX, VOCs and NH3, accounting for 15%, 14% and 13% of the national emissions of these pollutants, respectively
- Saskatchewan for VOCs, accounting for 14% of the national emissions of this pollutant
- Ontario for SOX, NH3, CO, PM2.5, accounting for 16%, 20%, 21%, and 17% of the national emissions of these pollutants, respectively
Distribution of air pollutant emissions by province and territory, Canada, 2023

Data table for the long description
Province or territory | Sulphur oxides (percentage of national emissions) |
Nitrogen oxides (percentage of national emissions) |
Volatile organic compounds (percentage of national emissions) |
Ammonia (percentage of national emissions) |
Carbon monoxide (percentage of national emissions) |
Fine particulate matter (percentage of national emissions) |
---|---|---|---|---|---|---|
Newfoundland and Labrador | 1.3 | 2.7 | 1.0 | 0.2 | 1.3 | 1.3 |
Prince Edward Island | <0.1 | 0.2 | 0.3 | 0.6 | 0.4 | 0.3 |
Nova Scotia | 6.2 | 2.2 | 1.6 | 0.7 | 2.1 | 1.4 |
New Brunswick | 2.2 | 1.8 | 1.4 | 0.8 | 1.9 | 1.1 |
Quebec | 15.4 | 9.7 | 14.0 | 13.2 | 26.1 | 11.5 |
Ontario | 15.8 | 14.3 | 20.4 | 19.8 | 21.1 | 16.6 |
Manitoba | 0.3 | 2.2 | 4.1 | 11.3 | 4.5 | 6.8 |
Saskatchewan | 19.3 | 8.9 | 14.1 | 22.0 | 7.2 | 26.2 |
Alberta | 27.0 | 42.3 | 34.6 | 27.2 | 23.0 | 24.5 |
British Columbia | 27.0 | 42.3 | 34.6 | 27.2 | 23.0 | 9.4 |
Yukon | <0.1 | 0.2 | <0.1 | <0.1 | 0.2 | 0.3 |
Northwest Territories | <0.1 | 0.9 | 0.1 | <0.1 | 0.2 | 0.3 |
Nunavut | <0.1 | 0.9 | <0.1 | <0.1 | 0.1 | 0.3 |
Note: The percentages have been rounded off and their sum may not add up to 100.
Download data file (Excel/CSV; 1.97 kB)
How this indicator was calculated
Note: The indicator reports emissions of 6 key air pollutants from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation. Emissions from black carbon, a component of PM2.5, are also not included. Consult the black carbon section for a detailed analysis of the pollutant.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
By pollutant
Sulphur oxides
Sulphur oxide emissions by source
Emissions of sulphur oxides (SOX) ) to the atmosphere can result in adverse effects on human health and the environment. The SOX emissions released by human activities are mostly in the form of sulphur dioxide (SO2). Sulphur dioxide can affect the respiratory systems of humans and animals and can cause damage to vegetation, buildings and materials. It also contributes to the formation of fine particulate matter (PM2.5) and acid rain.
Key results
- Between 1990 and 2023, SOX emissions decreased by 80% from 3 010 kilotonnes (kt) to 608 kt
- In 2023, 3 sources accounted for 93% (567 kt) of the total SOX emissions: the oil and gas industry, the ore and mineral industries and electric utilities
Total sulphur oxide emissions by source, Canada, 1990 to 2023

Data table for the long description
Year | Oil and gas industry (emissions in kilotonnes) |
Ore and mineral industries (emissions in kilotonnes) |
Electric utilities (emissions in kilotonnes) |
Other sources (emissions in kilotonnes) |
Total emissions (emissions in kilotonnes) |
---|---|---|---|---|---|
1990 | 535.6 | 1 483.3 | 618.4 | 372.6 | 3 009.9 |
1991 | 541.6 | 1 336.3 | 592.1 | 325.1 | 2 795.2 |
1992 | 580.9 | 1 171.5 | 610.7 | 311.6 | 2 674.7 |
1993 | 608.5 | 1 114.9 | 547.2 | 316.5 | 2 587.2 |
1994 | 604.6 | 894.5 | 559.8 | 317.1 | 2 376.1 |
1995 | 598.4 | 1 108.3 | 532.6 | 269.2 | 2 508.5 |
1996 | 597.3 | 1 091.3 | 542.2 | 282.5 | 2 513.3 |
1997 | 552.8 | 1 034.1 | 591.3 | 281.4 | 2 459.7 |
1998 | 523.4 | 1 021.7 | 603.6 | 274,5 | 2 423.1 |
1999 | 516.1 | 927.7 | 601.1 | 279.2 | 2 324.1 |
2000 | 513.3 | 916.8 | 619.2 | 279.3 | 2 328.6 |
2001 | 497.9 | 914.2 | 623.9 | 274.4 | 2 310.4 |
2002 | 468.1 | 905.7 | 624.3 | 269.4 | 2 267.5 |
2003 | 475.6 | 814.1 | 630.4 | 276.8 | 2 196.9 |
2004 | 468.1 | 876.3 | 581.5 | 283.3 | 2 209.2 |
2005 | 462.2 | 859.1 | 521.9 | 252.2 | 2 095.4 |
2006 | 424.3 | 827.6 | 458.9 | 183.4 | 1 894.3 |
2007 | 402.4 | 779.8 | 491.9 | 170.8 | 1 844.8 |
2008 | 378.3 | 716.1 | 427.5 | 143.7 | 1 665.5 |
2009 | 371.8 | 523.1 | 384.0 | 122.4 | 1 401.3 |
2010 | 339.3 | 502.1 | 333.9 | 115.5 | 1 290.9 |
2011 | 328.5 | 467.8 | 293.2 | 109.6 | 1 199.1 |
2012 | 330.5 | 477.5 | 284.2 | 94.3 | 1 186.6 |
2013 | 315.5 | 492.9 | 278.2 | 82.8 | 1 169.3 |
2014 | 286.8 | 487.8 | 269.2 | 77.4 | 1 121.1 |
2015 | 260.5 | 483.5 | 251.5 | 66.8 | 1 060.3 |
2016 | 246.2 | 481.5 | 253.1 | 57.7 | 1 038.5 |
2017 | 254.7 | 389.1 | 245.4 | 54.4 | 943.6 |
2018 | 265.7 | 258.2 | 220.2 | 56.0 | 800.1 |
2019 | 266.9 | 183.3 | 205.4 | 51.8 | 707.3 |
2020 | 243.6 | 195.3 | 168.2 | 42.9 | 649.9 |
2021 | 262.6 | 162.2 | 169.0 | 45.5 | 639.3 |
2022 | 277.5 | 175.0 | 154.2 | 45.9 | 652.6 |
2023 | 264.3 | 167.8 | 134.8 | 41.3 | 608.1 |
Note: The numbers have been rounded off and their sum may not correspond to the total.
Download data file (Excel/CSV; 2.67 kB)
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation. The category "other sources" includes emissions from transportation (road, rail, air and marine), off-road vehicles and mobile equipment, home firewood burning, incineration and waste, agriculture (livestock, crop production and fertilizer), dust and fires, paints and solvents, building heating and energy generation, manufacturing, and other miscellaneous sources. Consult Table 1 in the Data sources and methods for a complete list of the air pollutant emissions sources included under each category. The interactive figures provide a dynamic and customizable format to explore the emissions.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
In 2023, the oil and gas industry accounted for approximately 43% of total national SOX emissions (264 kt). Electric utilities and ore and mineral industries followed with 22% (135 kt) and 28% (168 kt) of national emissions, respectively. For the ore and mineral industries, 35% (59 kt) of its SOX emissions came from the non-ferrous refining and smelting industry.
The largest reduction in emissions between 1990 and 2023 was from ore and mineral industries with a reduction in emissions of approximately 1 316 kt. The largest driver of the reduction from this source was from the non-ferrous refining and smelting industry with a reduction of 1 207 kt over the period.
This significant decrease in SOX emissions from 1990 to 2023 (80%) is due in large part to government actions to fight acid rain and related federal-provincial and United States agreementsFootnote 1 Footnote 2 on capping SOX emissions by 1994. Further reductions were also realized through:
- technological upgrades, new air pollution controls for non-ferrous metal smelters and the closure of 4 major smelters in Manitoba, Ontario, Quebec and New Brunswick
- lower emissions from fossil-fuel-fired (such as, coal-fired) power-generating utilities due to better technologies and plant closures (for example, the phase-out of coal electricity generation in Ontario and Alberta)
- implementation of regulations on low-sulphur fuelsFootnote 3 Footnote 4
More recently, between 2022 and 2023, SOX emissions have declined due to decreases in emissions from the electric utilities industry of 19 kt (13%), largely driven by reduced use of coal power plants and increased use of cleaner fuels.
Sulphur oxide emissions by province and territory
Key results
- In 2023, Alberta and Saskatchewan accounted for 27% (164 kt) and 19% (117 kt) of national SOX emissions
- Between 1990 and 2023
- the largest reductions were observed in Ontario and Manitoba. Emissions in these provinces decreased by 1 028 kt (91%) and 507 kt (99.6%), respectively
- Saskatchewan was the only province that had an increase in SOX emissions (15%, or 15 kt)
Sulphur oxide emissions by province and territory, Canada, 1990, 2005 and 2023

Data table for the long description
Province or territory | 1990 (emissions in kilotonnes) |
2005 (emissions in kilotonnes) |
2023 (emissions in kilotonnes) |
---|---|---|---|
Newfoundland and Labrador | 70.0 | 51.2 | 8.1 |
Prince Edward Island | 3.7 | 2.8 | 0.2 |
Nova Scotia | 203.1 | 149.7 | 37.7 |
New Brunswick | 109.0 | 93.4 | 13.2 |
Quebec | 251.0 | 226.3 | 93.6 |
Ontario | 1 124.1 | 500.1 | 96.1 |
Manitoba | 508.7 | 397.0 | 2.0 |
Saskatchewan | 102.3 | 146.9 | 117.4 |
Alberta | 510.3 | 459.3 | 164.4 |
British Columbia | 109.1 | 65.0 | 75.1 |
Yukon | 0.6 | 1.3 | <0.1 |
Northwest Territories | 18.0[A] | 0.8 | 0.4 |
Nunavut[A] | n/a | 1.7 | 0.2 |
Download data file (Excel/CSV; 1.21 kB)
Note: [A] 1990 emissions data for the Northwest Territories include emissions for Nunavut, which was part of the Northwest Territories until 1999. n/a = not applicable.
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
Alberta had the highest SOX emissions level in 2023, accounting for 27% (164 kt) of total national emissions. Emissions in the province mainly came from the oil and gas industry and electric utilities, combined, accounting for 94% (155 kt) of the emissions. Between 2005 and 2023, the province experienced a 64% decline in emissions (295 kt) with the oil and gas industry, notably reductions from natural gas processing and oil sands mining extraction and processing, accounting for a large part of the reductions since 2005.
Saskatchewan was the second-highest emitter of SOX in 2023, accounting for 19% (117 kt) of total national emissions. Emissions from electric utilities, specifically coal electric power generation, was the largest contributor to SOX emissions in the province.
Ontario ranked third, with 16% (96 kt) of total national emissions of SOX; the ore and mineral industries sector was the most important source of emissions in the province in 2023.
Sulphur oxide emissions by facilities
The National Pollutant Release Inventory provides detailed information on air pollutant emissions from industrial and commercial facilities that meet its reporting criteria.Footnote 5
The Canadian Environmental Sustainability Indicators provide access to this information through an interactive map. The map allows you to explore SOX emissions from individual facilities.
Key results
- In 2023, 2 653 facilities across Canada reported SOX emissions representing 90% of total national emissions. Of these facilities:
- 2 206 facilities reported emissions under 25 tonnes (t)
- 428 facilities reported emissions between 25 to 6 000 t
- 19 facilities reported emissions of 6 000 t or more located in Quebec (5), Ontario (4), Alberta (4), Saskatchewan (3), Nova Scotia (2) and British Columbia (1)
Sulphur oxide emissions by reporting facilities, Canada, 2023

Long description
The map of Canada shows the amount of sulphur oxide emissions in tonnes in 2023 by reporting facility. The categories are: 0 to 25 tonnes, 25 to 100 tonnes, 100 to 500 tonnes, 500 to 2 000 tonnes, 2 000 to 6 000 tonnes and 6 000 tonnes or more.
Source: Environment and Climate Change Canada (2025) National Pollutant Release Inventory.
Navigate data using the interactive map
Nitrogen oxides
Nitrogen oxide emissions by source
Nitrogen oxides (NOX) include emissions of nitric oxide (NO) and nitrogen dioxide (NO2). Nitrogen dioxide can have adverse effects on human health and the environment. Nitrogen oxides contribute to acid rain, which can lead to the acidification of aquatic and terrestrial ecosystems. It also contributes to the eutrophication of lakes and to the formation of ground-level ozone (O3) and fine particulate matter (PM2.5).
Key results
- In 2023, NOX emissions were 1 228 kilotonnes (kt); this is 45% lower than in 1990
- The oil and gas industry was the largest source of NOX, representing 37% (452 kt) of total emissions in 2023
Total nitrogen oxide emissions by source, Canada, 1990 to 2023

Data table for the long description
Year | Oil and gas industry (emissions in kilotonnes) |
Transportation (road, rail, air and marine) (emissions in kilotonnes) |
Other sources (emissions in kilotonnes) |
Off-road vehicles and mobile equipment (emissions in kilotonnes) |
Electric utilities (emissions in kilotonnes) |
Total emissions (emissions in kilotonnes) |
---|---|---|---|---|---|---|
1990 | 343.5 | 894.8 | 373.8 | 366.7 | 257.0 | 2 235.8 |
1991 | 337.1 | 890.0 | 360.3 | 337.9 | 250.9 | 2 176.2 |
1992 | 353.0 | 931.5 | 362.4 | 354.4 | 332.7 | 2 234.5 |
1993 | 378.4 | 998.9 | 361.6 | 337.0 | 243.0 | 2 318.9 |
1994 | 410.3 | 1 103.3 | 367.3 | 348.2 | 240.0 | 2 469.1 |
1995 | 426.3 | 1 140.6 | 367.1 | 359.9 | 248.1 | 2 542.0 |
1996 | 438.2 | 1 176.1 | 364.6 | 367.5 | 269.0 | 2 615.4 |
1997 | 482.1 | 1 207.8 | 364.1 | 386.0 | 287.7 | 2 727.3 |
1998 | 493.7 | 1 208.8 | 348.0 | 380.7 | 310.1 | 2 741.3 |
1999 | 511.1 | 1 190.7 | 351.4 | 384.0 | 306.4 | 2 743.5 |
2000 | 456.4 | 1 159.9 | 354.8 | 394.8 | 326.8 | 2 692.6 |
2001 | 450.9 | 1 095.8 | 334.8 | 373.7 | 313.0 | 2 568.2 |
2002 | 451.8 | 1 054.8 | 362.6 | 352.4 | 314.9 | 2 546.5 |
2003 | 492.9 | 1 004.8 | 360.1 | 352.2 | 293.0 | 2 503.0 |
2004 | 427.2 | 962.6 | 355.1 | 342.1 | 267.5 | 2 354.5 |
2005 | 427.5 | 917.0 | 326.2 | 334.2 | 253.7 | 2 258.7 |
2006 | 427.3 | 865.5 | 276.8 | 307.4 | 224.3 | 2 101.3 |
2007 | 450.1 | 847.0 | 267.4 | 284.3 | 238.8 | 2 087.6 |
2008 | 460.0 | 802.2 | 246.3 | 267.8 | 225.1 | 2 001.4 |
2009 | 455.0 | 745.6 | 219.5 | 234.0 | 218.0 | 1 872.1 |
2010 | 445.1 | 719/3 | 227.4 | 259.5 | 233.7 | 1 885.0 |
2011 | 457.0 | 628.8 | 232.0 | 267.1 | 199.8 | 1 784.7 |
2012 | 449.8 | 579.2 | 228.5 | 250.7 | 166.3 | 1 674.5 |
2013 | 454.0 | 547.6 | 226.4 | 245.3 | 162.0 | 1 635.3 |
2014 | 462.5 | 512.9 | 227.8 | 226.6 | 167.2 | 1 597.0 |
2015 | 463.9 | 455.1 | 224.2 | 236.5 | 152.3 | 1 532.0 |
2016 | 456.1 | 402.5 | 219.0 | 224.6 | 152.4 | 1 455.5 |
2017 | 463.8 | 384.1 | 232.0 | 237.6 | 145.0 | 1 462.4 |
2018 | 470.0 | 378.5 | 228.0 | 232.4 | 129.0 | 1 437.8 |
2019 | 468.4 | 357.4 | 225.7 | 220.6 | 124.8 | 1 396.8 |
2020 | 444.3 | 302.1 | 213.9 | 188.7 | 101.9 | 1 250.9 |
2021 | 438.8 | 298.6 | 219.9 | 184.5 | 100.1 | 1 241.9 |
2022 | 443.3 | 301.2 | 219.5 | 173.9 | 93.8 | 1 231.8 |
2023 | 451.5 | 302.4 | 219.2 | 164.6 | 90.1 | 1 227.8 |
Note: The numbers have been rounded off and their sum may not correspond to the total.
Download data file (Excel/CSV; 2.87 kB)
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation. The category "other sources" includes emissions from ore and mineral industries, manufacturing, building heating and energy generation, home firewood burning, incineration and waste, agriculture (livestock, crop production and fertilizer), dust and fires, paints and solvents, and other miscellaneous sources. Consult Table 1 in the Data sources and methods for a complete list of the air pollutant emissions sources included under each category. The interactive figures provide a dynamic and customizable format to explore the emissions.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
The oil and gas industry was the largest contributor of NOX emissions between 1990 and 2023. Emissions of NOX from this sector increased by 108 kt (31%) during that period.
The transportation (road, rail, air, and marine) sector emitted the next largest proportion of NOX emissions in 2023, representing 25% (303 kt) of total national emissions. This sector also experienced the largest decrease in emissions (592 kt or 66%) between 1990 and 2023.
The decline in NOX emissions between 1990 and 2023 is mostly attributable to 2 factors:
- the reduction in emissions from transportation after 2000, given the progressive introduction of cleaner technology and fuels for vehicles
- lower emissions from fossil-fuel-fired (for example, coal-fired) power-generating utilities as a result of better emission control technologies and certain plant closures (for example, the closure of coal power plants in Ontario)
More recently, between 2022 and 2023, NOX emissions from transportation (road, rail, air and marine) sources have increased by 1 kt (0.4%), notably from domestic marine navigation. Likewise, the oil and gas industry saw NOx emissions increase by 8 kt (2%) between 2022 and 2023.
Nitrogen oxide emissions by province and territory
Key results
- In 2023, among provinces and territories, Alberta emitted the most NOX. The province accounted for 42% (520 kt) of national emissions
- Between 1990 and 2023,
- the largest reduction was observed in Ontario. Emissions decreased by 415 kt (70%) in the province
- NOX emissions increased in Northwest Territories and Nunavut by 61% (8 kt)Footnote 6
Nitrogen oxide emissions by province and territory, Canada, 1990, 2005 and 2023

Data table for the long description
1990 (emissions in kilotonnes) |
2005 (emissions in kilotonnes) |
2023 (emissions in kilotonnes) |
|
---|---|---|---|
Newfoundland and Labrador | 50.8 | 57.4 | 33.5 |
Prince Edward Island | 6.3 | 6.8 | 2.8 |
Nova Scotia | 81.1 | 88.4 | 26.7 |
New Brunswick | 77.6 | 69.9 | 21.6 |
Quebec | 304.9 | 288.1 | 118.9 |
Ontario | 590.2 | 537.7 | 175.1 |
Manitoba | 69.6 | 66.3 | 27.0 |
Saskatchewan | 146.3 | 170.9 | 109.7 |
Alberta | 605.4 | 663.0 | 519.7 |
British Columbia | 287.0 | 285.7 | 169.0 |
Yukon | 3.3 | 2.5 | 2.3 |
Northwest Territories | 13.4[A] | 14.3 | 10.5 |
Nunavut[A] | n/a | 7.8 | 11.0 |
Download data file (Excel/CSV; 1.25 kB)
Note: [A] 1990 emissions data for the Northwest Territories include emissions for Nunavut, which was part of the Northwest Territories until 1999. n/a = not applicable.
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
The oil and gas industry is an important source of NOX emissions in Alberta, accounting for 68% (352 kt) of the province's NOX emissions in 2023. The increasing contribution of this sector to the province's emissions between 1990 and 2023 was more than offset by emission reductions from the transport and electric utilities sectors.
British Columbia and Ontario contributed the second and third largest proportions of NOX emissions in 2023, with British Columbia accounting for 14% (169 kt) and Ontario accounting for 14% (175 kt) of total national emissions, with transportation (road, rail, air and marine) being the most important source in both provinces followed by the oil and gas industry in British Columbia and off-road vehicles and mobile equipment in Ontario. However, Ontario experienced the largest decrease in emissions (415 kt) between 1990 and 2023 in large part due to emission reductions from transportation (road, rail, air and marine), electric utilities, manufacturing, ore and mineral industries and off-road vehicles and mobile equipment. In Ontario, the majority of total NOX emission reductions occurred between 2005 and 2023 (363 kt).
Quebec ranked fourth, with 10% (119 kt) of total national emissions. Transportation (road, rail, air and marine) was the most important source of NOX in this province. Quebec also experienced a large decrease in emissions (169 kt) between 2005 and 2023 mainly due to emission reductions from transportation (road, rail, air and marine).
Nitrogen oxide emissions by facilities
The National Pollutant Release Inventory provides detailed information on air pollutant emissions from industrial and commercial facilities that meet its reporting criteria.
The Canadian Environmental Sustainability Indicators provide access to this information through an interactive map. The map allows you to explore NOX emissions from individual facilities.
Key results
- In 2023, 3 917 facilities across Canada reported NOX emissions representing 43% of total national emissions. Of these facilities:
- 2 452 facilities reported emissions under 50 tonnes (t)
- 1 348 facilities reported emissions between 50 to 800 t
- 117 facilities reported emissions of 800 t or more located in Alberta (43), Ontario (18), Quebec (14), British Columbia (9), Saskatchewan (8), Newfoundland and Labrador (7), Nova Scotia (6), New Brunswick (5), Northwest Territories (3), Nunavut (3), and Manitoba (1)
Nitrogen oxide emissions by reporting facilities, Canada, 2023

Long description
The map of Canada shows the amount of nitrogen oxide emissions in tonnes in 2023 by reporting facility. The categories are: 0 to 50 tonnes, 50 to 100 tonnes, 100 to 200 tonnes, 200 to 400 tonnes, 400 to 800 tonnes and 800 tonnes or more.
Source: Environment and Climate Change Canada (2025) National Pollutant Release Inventory.
Navigate data using the interactive map
Volatile organic compounds
Volatile organic compound emissions by source
Volatile organic compounds (VOCs) are carbon-containing gases and vapours released into the atmosphere by natural sources and human activities. Footnote 7 There are hundreds of VOCs that are emitted and that affect the health of Canadians and the environment. VOCs are primary precursors to the formation of ground-level ozone and particulate matter which are the main pollutants contributing to the formation of smog.
Key results
- In 2023, VOC emissions in Canada were 1 368 kilotonnes (kt); this is a 38% (832 kt) decrease from 1990 levels
- Since 1990, the oil and gas industry has been the highest contributor to VOC emissions. In 2023, the sector accounted for 40% (541 kt) of total emissions
Total volatile organic compound emissions by source, Canada, 1990 to 2023

Data table for the long description
Year | Oil and gas industry (emissions in kilotonnes) |
Paints and solvents (emissions in kilotonnes) |
Off-road vehicles and mobile equipment (emissions in kilotonnes |
Agriculture (livestock, crop production and fertilizer) (emissions in kilotonnes) |
Manufacturing (emissions in kilotonnes) |
Other sources (emissions in kilotonnes) |
Transportation (road, rail, air and marine) (emissions in kilotonnes) |
Home firewood burning (emissions in kilotonnes) |
Total emissions (emissions in kilotonnes) |
---|---|---|---|---|---|---|---|---|---|
1990 | 606.6 | 343.3 | 287.0 | 103.6 | 257.1 | 147.7 | 346.8 | 108.0 | 2 200.2 |
1991 | 601.8 | 336.0 | 286.9 | 103.6 | 253.8 | 148.9 | 335.4 | 109.6 | 2 176.0 |
1992 | 615.8 | 338.3 | 296.4 | 105.3 | 254.7 | 133.7 | 345.5 | 116.4 | 2 206.2 |
1993 | 644.0 | 337.1 | 305.1 | 105.1 | 271.1 | 156.9 | 362.4 | 117.6 | 2 299.4 |
1994 | 661.7 | 348.1 | 322.2 | 107.5 | 273.0 | 153.3 | 384.2 | 115.1 | 2 365.0 |
1995 | 673.0 | 361.3 | 382.4 | 111.5 | 262.8 | 148.1 | 376.9 | 113.1 | 2 429.0 |
1996 | 701.2 | 358.7 | 409.6 | 114.5 | 262.3 | 137.6 | 380.2 | 116.0 | 2 480.1 |
1997 | 688.4 | 359.8 | 440.0 | 115.2 | 257.5 | 125.9 | 373.4 | 115.8 | 2 475.9 |
1998 | 700.8 | 361.6 | 467.2 | 115.6 | 261.5 | 127.0 | 366.4 | 93.2 | 2 493.3 |
1999 | 653.6 | 373.1 | 490.7 | 116.0 | 259.3 | 120.3 | 351.6 | 90.7 | 2 455.3 |
2000 | 667.9 | 379.7 | 489.5 | 116.9 | 254.5 | 117.2 | 330.3 | 92.5 | 2 448.4 |
2001 | 672.3 | 357.5 | 495.4 | 119.9 | 229.6 | 112.7 | 309.9 | 80.1 | 2 377.3 |
2002 | 683.6 | 361.2 | 497.7 | 121.0 | 232.8 | 108.1 | 290.1 | 77.8 | 2 372.2 |
2003 | 676.5 | 364.1 | 482.9 | 120.6 | 216.0 | 120.1 | 263.5 | 73.8 | 2 317.7 |
2004 | 656.0 | 362.2 | 471.5 | 124.5 | 200.9 | 108.1 | 243.8 | 79.1 | 2 246.1 |
2005 | 652.4 | 428.9 | 448.6 | 125.6 | 187.1 | 105.6 | 215.9 | 82.0 | 2 256.1 |
2006 | 630.4 | 417.1 | 417.8 | 123.0 | 165.3 | 96.3 | 198.2 | 80.9 | 2 129.1 |
2007 | 627.4 | 409.4 | 375.3 | 120.9 | 149.8 | 92.9 | 188.3 | 95.3 | 2 059.2 |
2008 | 634.0 | 392.3 | 338.1 | 118.9 | 133.8 | 91.9 | 172.9 | 95.2 | 1 977.1 |
2009 | 586.9 | 353.3 | 314.8 | 116.2 | 113.0 | 91.0 | 160.2 | 96.4 | 1 831.7 |
2010 | 569.2 | 361.4 | 319.8 | 115.2 | 118.2 | 90.8 | 148.7 | 85.4 | 1 808.7 |
2011 | 557.2 | 349.7 | 301.2 | 114.1 | 115.8 | 92.5 | 115.1 | 90.9 | 1 736.6 |
2012 | 607.6 | 354.6 | 274.8 | 114.8 | 117.7 | 89.7 | 107.6 | 86.3 | 1 753.1 |
2013 | 658.0 | 357.0 | 254.9 | 116.1 | 115.9 | 84.1 | 103.3 | 96.1 | 1 785.4 |
2014 | 693.7 | 363.6 | 220.1 | 115.3 | 110.0 | 89.9 | 95.9 | 98.7 | 1 787.1 |
2015 | 666.1 | 326.9 | 205.2 | 114.0 | 105.6 | 86.6 | 89.0 | 97.7 | 1 691.1 |
2016 | 599.3 | 310.4 | 199.6 | 114.6 | 104.5 | 83.4 | 83.8 | 93.5 | 1 589.2 |
2017 | 616.2 | 307.2 | 187.2 | 114.9 | 100.7 | 81.8 | 79.4 | 94.7 | 1 582.1 |
2018 | 637.6 | 313.1 | 175.2 | 115.7 | 108.6 | 82.4 | 78.6 | 91.0 | 1 632.2 |
2019 | 613.6 | 305.2 | 165.0 | 115.4 | 103.5 | 82.9 | 75.8 | 81.7 | 1 543.1 |
2020 | 526.5 | 262.1 | 144.3 | 115.2 | 97.7 | 75.4 | 63.4 | 70.6 | 1 355.3 |
2021 | 525.0 | 272.6 | 139.9 | 115.7 | 112.0 | 77.7 | 64.7 | 64.4 | 1 371.9 |
2022 | 533.3 | 271.5 | 129.9 | 114.9 | 107.3 | 76.0 | 65.6 | 69.3 | 1 366.8 |
2023 | 540.5 | 271.5 | 127.6 | 113.6 | 109.6 | 75.5 | 66.3 | 63.3 | 1 367.8 |
Note: The numbers have been rounded off and their sum may not correspond to the total.
Download data file (Excel/CSV; 3.29 kB)
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation. The category "other sources" includes emissions from incineration and waste, ore and mineral industries, dust and fires, building heating and energy generation, electric utilities and other miscellaneous sources. Consult Table 1 in the Data sources and methods for a complete list of the air pollutant emissions sources included under each category. The interactive figures provide a dynamic and customizable format to explore the emissions.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
Apart from the oil and gas industry, paints and solvents, and off-road vehicles and mobile equipment were also important sources of VOC emissions in 2023 contributing 20% (271 kt) and 9% (128 kt) of total emissions, respectively.
The largest emissions reduction between 1990 and 2023 was from transportation (road, rail, air and marine), with emissions reductions of 281 kt (81%).
The long-term decrease in VOC emissions is mainly attributable to 3 factors:
- the progressive introduction of cleaner technologies and fuels resulting in emission reductions from transportation, off-road vehicles and mobile equipment
- emission reductions from most industrial and non-industrial sources from facility closures, decrease in production and improved emission controls
- lower levels of VOCs in products such as paints, solvents and cleaners
Compared to the previous year, VOC emissions increased by 1 kt (0.1%) in 2023. The largest increase was from the oil and gas industry 7 kt (1%), notably light medium crude oil production which accounted for just under half of the overall oil and gas increase (3.4 kt).
Volatile organic compound emissions by province and territory
Key results
- Alberta emitted the highest proportion of VOCs in 2023, representing 35% (474 kt) of national emissions
- Between 1990 and 2023,
- Ontario experienced the largest reduction in VOC emissions; emissions in the province decreased by 311 kt (53%)
- Saskatchewan was the only province that experienced an increase in VOC emissions, with 16 kt (9%), primarily due to the oil and gas industry
Volatile organic compound emissions by province and territory, Canada, 1990, 2005 and 2023

Data table for the long description
Province or territory | 1990 (emissions in kilotonnes) |
2005 (emissions in kilotonnes) |
2023 (emissions in kilotonnes) |
---|---|---|---|
Newfoundland and Labrador | 32.2 | 31.2 | 13.3 |
Prince Edward Island | 8.4 | 8.1 | 3.8 |
Nova Scotia | 50.2 | 47.8 | 21.5 |
New Brunswick | 39.9 | 48.5 | 18.7 |
Quebec | 345.9 | 343.6 | 192.1 |
Ontario | 589.7 | 571.1 | 278.6 |
Manitoba | 71.4 | 83.2 | 55.8 |
Saskatchewan | 177.5 | 256.4 | 193.3 |
Alberta | 590.5 | 613.4 | 473.6 |
British Columbia | 282.6 | 240.9 | 113.3 |
Yukon | 1.5 | 2.1 | 1.0 |
Northwest Territories | 10.3[A] | 8.5 | 1.9 |
Nunavut[A] | n/a | 1.3 | 0.9 |
Download data file (Excel/CSV; 1.22 kB)
Note: [A] 1990 emissions data for the Northwest Territories include emissions for Nunavut, which was part of the Northwest Territories until 1999. n/a = not applicable.
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
Alberta was the highest emitting province of VOCs in 2023 (474 kt), with the oil and gas industry as the main source, contributing 74% (349 kt) of the province's emissions
Ontario was the second-highest emitter of VOCs, accounting for 20% (279 kt) of total national emissions in 2023. The main emission sources are paints and solvents, off-road vehicles and mobile equipment, and manufacturing. Ontario also experienced the largest reduction in emissions, with 311 kt (53%) between 1990 and 2023, mainly as a result of emission reductions from manufacturing and transportation (road, rail, air and marine). The majority of the reductions in Ontario occurred between 2005 and 2023 (292 kt).
Saskatchewan was the third largest emitter, with 14% (193 kt) of total national emissions in 2023, where the oil and gas industry accounted for 73% of the emissions in that province.
Volatile organic compound emissions by facilities
The National Pollutant Release Inventory provides detailed information on air pollutant emissions from industrial and commercial facilities that meet its reporting criteria.
The Canadian Environmental Sustainability Indicators provide access to this information through an interactive map. The map allows you to explore VOC emissions from individual facilities.
Key results
- In 2023, 4 755 facilities across Canada reported VOC emissions representing 17% of total national emissions. Of these facilities:
- 3 099 facilities reported emissions under 15 tonnes (t)
- 1 579 facilities reported emissions between 15 to 400 t
- 77 facilities reported emissions of 400 t or more located in Alberta (27), Ontario (21), Saskatchewan (8), Quebec (8), Manitoba (4), New Brunswick (3), Newfoundland and Labrador (3), British Columbia (2) and Nova Scotia (1)
Volatile organic compound emissions by reporting facilities, Canada, 2023

Long description
The map of Canada shows the amount of volatile organic compound emissions in tonnes in 2023 by reporting facility. The categories are: 0 to 15 tonnes, 15 to 30 tonnes, 30 to 100 tonnes, 100 to 200 tonnes, 200 to 400 tonnes and 400 tonnes or more.
Source: Environment and Climate Change Canada (2025) National Pollutant Release Inventory.
Navigate data using the interactive map
Ammonia
Ammonia emissions by source
Ammonia (NH3) is a colourless gas with a noticeable odour at high concentrations. It can be poisonous if inhaled in great quantities and is irritating to the eyes, nose, and throat. It can also contribute to the nitrification and eutrophication of aquatic systems. In the air, the gas combines with sulphates and nitrates to form secondary fine particulate matter (PM2.5).
Key results
- In 2023, NH3 emissions were 495 kilotonnes (kt), which is 25% higher than in 1990
- Agriculture (livestock, crop production and fertilizer) was the main source of NH3 emissions in 2023. Emissions from this source accounted for more than 94% (463 kt) of total national emissions
Total ammonia emissions by source, Canada, 1990 to 2023

Data table for the long description
Year | Agriculture (livestock, crop production and fertilizer) (emissions in kilotonnes) |
Other sources (emissions in kilotonnes) |
Manufacturing (emissions in kilotonnes) |
Transportation (road, rail, air and marine) (emissions in kilotonnes) |
Total emissions (emissions in kilotonnes) |
---|---|---|---|---|---|
1990 | 356.6 | 13.0 | 20.0 | 5.6 | 395.2 |
1991 | 353.5 | 13.3 | 19.1 | 6.2 | 392.1 |
1992 | 364.8 | 13.6 | 19.1 | 7.2 | 404.7 |
1993 | 367.6 | 14.4 | 18.5 | 8.3 | 408.8 |
1994 | 379.6 | 14.6 | 19.9 | 9.4 | 423.5 |
1995 | 396.8 | 16.5 | 26.6 | 9.9 | 449.8 |
1996 | 413.1 | 16.2 | 26.2 | 10.7 | 466.2 |
1997 | 418.7 | 16.3 | 25.2 | 11.1 | 471.3 |
1998 | 417.9 | 16.4 | 26.0 | 11.5 | 471.9 |
1999 | 415.6 | 14.6 | 24.8 | 11.6 | 466.7 |
2000 | 424.7 | 14.3 | 25.0 | 11.8 | 475.7 |
2001 | 427.9 | 13.9 | 21.8 | 11.9 | 475.5 |
2002 | 431.0 | 19.5 | 21.6 | 11.7 | 483.8 |
2003 | 437.5 | 12.0 | 18.9 | 11.5 | 479.9 |
2004 | 452.4 | 11.6 | 18.6 | 11.3 | 493.9 |
2005 | 448.7 | 13.2 | 17.2 | 10.7 | 489.9 |
2006 | 440.4 | 12.0 | 16.2 | 10.2 | 478.8 |
2007 | 446.2 | 11.4 | 16.1 | 10.1 | 483.8 |
2008 | 440.1 | 12.6 | 13.6 | 9.5 | 475.8 |
2009 | 425.9 | 12.3 | 12.7 | 9.1 | 460.0 |
2010 | 418.3 | 12.9 | 11.6 | 8.7 | 451.6 |
2011 | 416.2 | 12.7 | 11.9 | 7.7 | 448.5 |
2012 | 433.2 | 11.7 | 12.0 | 7.4 | 464.3 |
2013 | 446.3 | 12.9 | 11.3 | 7.3 | 477.8 |
2014 | 437.1 | 13.2 | 11.3 | 7.0 | 468.6 |
2015 | 440.0 | 11.9 | 11.8 | 6.9 | 470.6 |
2016 | 440.0 | 12.2 | 12.1 | 6.9 | 471.2 |
2017 | 431.2 | 11.7 | 11.3 | 6.8 | 461.1 |
2018 | 447.4 | 12.1 | 12.1 | 6.9 | 478.4 |
2019 | 448.8 | 12.5 | 11.2 | 6.9 | 479.3 |
2020 | 462.6 | 11.9 | 12.2 | 5.8 | 492.5 |
2021 | 467.2 | 13.1 | 11.5 | 6.1 | 497.9 |
2022 | 451.7 | 13.9 | 10.5 | 6.4 | 482.4 |
2023 | 462.7 | 14.1 | 11.4 | 6.5 | 494.7 |
Note: The numbers have been rounded off and their sum may not correspond to the total.
Download data file (Excel/CSV; 2.53 kB)
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation. The category "other sources" includes emissions from incineration and waste, the oil and gas industry, home firewood burning, ore and mineral industries, electric utilities, building heating and energy generation, off-road vehicles and mobile equipment, dust and fires, paints and solvents, and other miscellaneous sources. Consult Table 1 in the Data sources and methods for a complete list of the air pollutant emissions sources included under each category. The interactive figures provide a dynamic and customizable format to explore the emissions.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
Between 1990 and 2023, agriculture (livestock, crop production and fertilizer) experienced the largest increase (106 kt or 30%) in NH3 emissions. It also remained the key source of NH3 emissions throughout that period. Emissions from manufacturing (11 kt), other sources (14 kt) and transportation (road, rail, air and marine) (6 kt) combined represented 6% of national emissions in 2023.
The growth in NH3 emissions from agriculture (livestock, crop production and fertilizer) between 1990 and 2023 is mainly due to the increased use of synthetic nitrogen fertilizers in crop production. Up to 2005, increasing livestock populations also added to the growth. However, from 2006 to 2011, livestock populations decreased and NH3 emissions from that source have since declined slowly. More recently, emissions from crop production have been steadily increasing since 2006.Footnote 8
Ammonia emissions by province and territory
Key results
- In 2023, Alberta and Saskatchewan accounted for almost half (243 kt) of national NH3 emissions
- Between 1990 and 2023,
- Ontario experienced the largest emissions reduction with 13 kt (12%)
- The largest increase in NH3 emissions was in Saskatchewan with emissions more than doubling (a 60 kt increase)
- Alberta and Manitoba also increased in NH3 emissions by 39 kt and 18 kt, respectively
Ammonia emissions by province and territory, Canada, 1990, 2005 and 2023

Data table for the long description
Province or territory | 1990 (emissions in kilotonnes) |
2005 (emissions in kilotonnes) |
2023 (emissions in kilotonnes) |
---|---|---|---|
Newfoundland and Labrador | 1.0 | 1.1 | 0.9 |
Prince Edward Island | 3.4 | 3.8 | 3.0 |
Nova Scotia | 4.9 | 4.6 | 3.3 |
New Brunswick | 4.6 | 5.7 | 4.1 |
Quebec | 65.3 | 67.7 | 65.3 |
Ontario | 111.0 | 101.9 | 98.1 |
Manitoba | 38.1 | 55.4 | 56.1 |
Saskatchewan | 48.6 | 84.0 | 108.8 |
Alberta | 95.3 | 140.4 | 134.6 |
British Columbia | 23.0 | 25.3 | 20.5 |
Yukon | <0.1 | <0.1 | <0.1 |
Northwest Territories | <0.1[A] | <0.1 | <0.1 |
Nunavut[A] | <0.1 | <0.1 | <0.1 |
Download data file (Excel/CSV; 1.16 kB)
Note: [A] 1990 emissions data for the Northwest Territories include emissions for Nunavut, which was part of the Northwest Territories until 1999. n/a = not applicable.
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
In 2023, Alberta emitted the most NH3 of all the provinces and territories, accounting for 27% (135 kt) of total national emissions. Saskatchewan contributed the second-largest proportion of NH3, representing 22% (109 kt).
Ontario followed with 20% (98 kt) of total national emissions. Livestock farms and the application of fertilizers were the most important sources of NH3 emissions in Ontario.
Virtually almost all of the increase in national emissions between 1990 and 2023 took place in Saskatchewan, Alberta and Manitoba.
Ammonia emissions by facilities
The National Pollutant Release Inventory provides detailed information on air pollutant emissions from industrial and commercial facilities that meet its reporting criteria.
The Canadian Environmental Sustainability Indicators provide access to this information through an interactive map. The map allows you to explore NH3 emissions from individual facilities.
Key results
- In 2023, 305 facilities across Canada reported NH3 emissions representing 4% of total national emissions. Of these facilities:
- 199 facilities reported emissions under 25 tonnes (t)
- 98 facilities reported emissions between 25 to 400 t
- 8 facilities rreported emissions of 400 t or more located in Alberta (5), British Columbia (1), Manitoba (1) and Saskatchewan (1)
Ammonia emissions by reporting facilities, Canada, 2023

Long description
The map of Canada shows the amount of ammonia emissions in tonnes in 2023 by reporting facility. The categories are: 0 to 5 tonnes, 5 to 25 tonnes, 25 to 50 tonnes, 50 to 100 tonnes, 100 to 400 tonnes and 400 tonnes or more.
Source: Environment and Climate Change Canada (2025) National Pollutant Release Inventory.
Navigate data using the interactive map
Carbon monoxide
Carbon monoxide emissions by source
Carbon monoxide (CO) is a colourless, odourless, tasteless and poisonous gas. Once inhaled into the bloodstream, it can inhibit the blood's capacity to carry oxygen to organs and tissues, affecting human health.
Key results
- In 2023,
- CO emissions in Canada were 4 518 kilotonnes (kt), a decrease of 65% from 1990 levels
- Off-road vehicles and mobile equipment was the largest source of CO emissions in Canada, representing 38% (1 713 kt) of total emissions
- Transportation (road, rail, air and marine) was the second largest source, representing 22% (1 001 kt) of CO emissions in Canada
Total carbon monoxide emissions by source, Canada, 1990 to 2023

Data table for the long description
Year | Off-road vehicles and mobile equipment (emissions in kilotonnes) |
Transportation (road, rail, air and marine) (emissions in kilotonnes) |
Oil and gas industry (emissions in kilotonnes) |
Home firewood burning (emissions in kilotonnes) |
Ore and mineral industries (emissions in kilotonnes) |
Other sources (emissions in kilotonnes) |
Total emissions (emissions in kilotonnes) |
---|---|---|---|---|---|---|---|
1990 | 3 476.5 | 6 104.8 | 333.7 | 915.7 | 389.8 | 1 861.1 | 13 081.6 |
1991 | 3 305.1 | 5 831.3 | 323.8 | 927.9 | 453.5 | 1 898.0 | 12 628.1 |
1992 | 3 236.4 | 5 911.6 | 338.4 | 983.1 | 482.8 | 1 697.1 | 12 649.4 |
1993 | 3 128.9 | 5 955.2 | 360.7 | 992.5 | 478.3 | 1 896.3 | 12 811.9 |
1994 | 3 154.1 | 6 043.2 | 397.8 | 970.6 | 461.9 | 1 861.3 | 12 889.4 |
1995 | 3 714.8 | 5 696.7 | 405.2 | 952.5 | 457.7 | 1 903.5 | 13 130.6 |
1996 | 3 779.4 | 5 520.2 | 417.5 | 977.5 | 447.3 | 1 660.0 | 12 801.7 |
1997 | 3 974.0 | 5 212.7 | 466.6 | 971.8 | 413.7 | 1 427.8 | 12 466.7 |
1998 | 4 160.3 | 4 935.3 | 484.7 | 781.0 | 397.9 | 1 357.3 | 12 116.4 |
1999 | 4 340.5 | 4 569.6 | 497.0 | 759.2 | 374.0 | 1 312.4 | 11 852.8 |
2000 | 4 315.4 | 4 441.4 | 441.9 | 772.0 | 396.1 | 1 217.2 | 11 584.1 |
2001 | 4 414.4 | 4 144.6 | 466.1 | 667.4 | 421.9 | 1 081.5 | 11 195.9 |
2002 | 4 559.9 | 3 839.8 | 499.6 | 646.7 | 491.6 | 945.6 | 10 983.3 |
2003 | 4 242.2 | 3 569.3 | 528.8 | 612.2 | 521.5 | 990.9 | 10 464.9 |
2004 | 4 054.0 | 3 258.2 | 544.2 | 501.0 | 499.9 | 717.0 | 9 683.6 |
2005 | 3 850.4 | 2 796.3 | 492.6 | 675.8 | 505.7 | 685.6 | 9 006.4 |
2006 | 3 592.2 | 2 546.3 | 502.2 | 665.1 | 509.7 | 486.5 | 8 302.0 |
2007 | 2 920.1 | 2 331.9 | 521.7 | 783.8 | 532.0 | 409.0 | 7 498.6 |
2008 | 2 642.6 | 2 156.9 | 538.8 | 785.3 | 546.8 | 402.1 | 7 072.4 |
2009 | 2 534.2 | 2 037.0 | 523.2 | 795.8 | 512.5 | 388.5 | 6 646.0 |
2010 | 2 861.3 | 1 892.4 | 518.0 | 706.8.5 | 537.0 | 345.9 | 6 861.4 |
2011 | 2 814.0 | 1 459.5 | 527.0 | 753.6.0 | 560.5 | 330.6 | 6 445.2 |
2012 | 2 611.0 | 1 369.1 | 528.5 | 717.1 | 552.0 | 352.0 | 6 129.7 |
2013 | 2 486.8 | 1 357.1 | 560.6 | 794.6 | 546.2 | 293.5 | 6 038.9 |
2014 | 2 148.3 | 1 319.7 | 544.3 | 812.5 | 515.0 | 380.8 | 5 720.6 |
2015 | 2 008.7 | 1 263.4 | 551.8 | 799.8 | 513.3 | 357.7 | 5 494.7 |
2016 | 2 055.0 | 1 248.4 | 533.0 | 764.4 | 557.7 | 342.1 | 5 500.6 |
2017 | 2 001.6 | 1 196.5 | 546.7 | 773.9 | 588.8 | 281.9 | 5 389.5 |
2018 | 1 943.8 | 1 185.5 | 563.7 | 754.2 | 526.6 | 254.0 | 5 227.8 |
2019 | 1 903.4 | 1 161.8 | 537.4 | 686.2 | 507.9 | 263.6 | 5 060.3 |
2020 | 1 706.5 | 998.0 | 509.7 | 592.0 | 512.3 | 228.6 | 4 547.1 |
2021 | 1 755.3 | 1 025.2 | 535.6 | 536.8 | 512.0 | 237.6 | 4 602.6 |
2022 | 1 694.8 | 986.5 | 521.8 | 569.4 | 501.2 | 278.3 | 4 553.1 |
2023 | 1 712.7 | 1 001.2 | 538.6 | 527.0 | 515.6 | 222.8 | 4 517.8 |
Note: The numbers have been rounded off and their sum may not correspond to the total.
Download data file (Excel/CSV; 3.20 kB)
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation. The category "other sources" includes emissions from dust and fires, electric utilities, building heating and energy generation, incineration and waste, agriculture (livestock, crop production and fertilizer), paints and solvents, manufacturing and other miscellaneous sources. Consult Table 1 in the Data sources and methods for a complete list of the air pollutant emissions sources included under each category. The interactive figures provide a dynamic and customizable format to explore the emissions.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
In 2023, transportation, off-road vehicles and mobile equipment were the 2 most important sources of CO. These sources combined represented 60% (2 714 kt) of national emissions.
The largest reduction in emissions between 1990 and 2023 occurred in transportation (road, rail, air and marine) with an emission decrease of 5 104 kt (84%).
The decline in CO emissions between 1990 and 2023 was mainly due to increasingly stringent engine and vehicle regulations and the progressive introduction of cleaner and more efficient technology in vehicles (for example, catalytic converters).
Carbon monoxide emissions by province and territory
Key results
- In 2023, Quebec, Alberta and Ontario accounted for 70% (3 172 kt) of national CO emissions
- Between 1990 and 2023,
- all provinces and territories experienced reductions in emissions
- the largest reductions occurred in Ontario (2 637 kt or 73%), British Columbia (1 788 kt or 77%) and Quebec (1 339 kt or 53%)
Carbon monoxide emissions by province and territory, Canada, 1990, 2005 and 2023

Data table for the long description
Province or territory | 1990 (emissions in kilotonnes) |
2005 (emissions in kilotonnes) |
2023 (emissions in kilotonnes) |
---|---|---|---|
Newfoundland and Labrador | 215.9 | 126.2 | 56.5 |
Prince Edward Island | 76.4 | 45.2 | 17.8 |
Nova Scotia | 372.8 | 226.5 | 96.4 |
New Brunswick | 313.6 | 243.5 | 85.3 |
Quebec | 2 518.5 | 1 895.3 | 1 179.7 |
Ontario | 3 589.2 | 2 470.8 | 951.7 |
Manitoba | 500.1 | 403.6 | 201.2 |
Saskatchewan | 829.3 | 682.4 | 326.6 |
Alberta | 2 287.7 | 1 655.9 | 1 040.1 |
British Columbia | 2 328.5 | 1 215.4 | 540.3 |
Yukon | 17.2 | 17.6 | 7.6 |
Northwest Territories | 28.4[A] | 17.7 | 8.5 |
Nunavut[A] | n/a | 6.3 | 6.1 |
Download data file (Excel/CSV; 1.24 kB)
Note: [A] 1990 emissions data for the Northwest Territories include emissions for Nunavut, which was part of the Northwest Territories until 1999. n/a = not applicable.
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
In 2023, Quebec emitted the most CO of all the provinces and territories, representing 26% (1 180 kt) of the total national emissions. Ore and mineral industries was the largest contributor to CO emissions in Quebec, representing 32% (376 kt) of the province’s total emissions. Within this sector, the aluminum industry accounted for 92% (346 kt) of the emissions.
The province of Alberta ranked second, with 23% (1 040 kt) of total national emissions in 2023, with 78% of those emissions from 2 sources; off-road vehicles and mobile equipment and the oil and gas industry.
Ontario, the third largest CO emitter, accounted for 21% (952 kt) of total national emissions. The off-road vehicles and mobile equipment sector accounted for 42% of the province's CO emissions.
The sharp decrease in emissions between 1990 and 2023 in all provinces and territories is mainly attributable to emission reductions from transportation (road, rail, air and marine), largely driven by improvements in fuel efficiency. Some of the largest reductions occurred between 2005 and 2023, notably for Ontario, with emissions decreasing by 1 519 kt (62%).
Carbon monoxide emissions by facilities
The National Pollutant Release Inventory provides detailed information on air pollutant emissions from industrial and commercial facilities that meet its reporting criteria.
The Canadian Environmental Sustainability Indicators provide access to this information through an interactive map. The map allows you to explore CO emissions from individual facilities.
Key results
- In 2023, 3 732 facilities across Canada reported CO emissions representing 19% of total national emissions. Of these facilities:
- 1 835 facilities reported emissions under 25 tonnes (t)
- 1 812 facilities reported emissions between 25 to 1 000 t
- 85 facilities reported emissions of 1 000 t or more located in Alberta (29), Ontario (18), Quebec (17), British Columbia (10), New Brunswick (6), Saskatchewan (4) and Newfoundland and Labrador (1)
Carbon monoxide emissions by reporting facilities, Canada, 2023

Long description
The map of Canada shows the amount of carbon monoxide emissions in tonnes in 2023 by reporting facility. The categories are: 0 to 25 tonnes, 25 to 50 tonnes, 50 to 100 tonnes, 100 to 500 tonnes, 500 to 100 tonnes and 1 000 tonnes or more.
Source: Environment and Climate Change Canada (2025) National Pollutant Release Inventory.
Navigate data using the interactive map
Fine particulate matter
Fine particulate matter emissions by source
Particulate matter (PM) is directly emitted into the air in solid or liquid form. It is also formed in the air from precursor substances such as sulphur oxides, nitrogen oxides, volatile organic compounds and ammonia.Footnote 9 Fine particulate matter (PM2.5) refers to particulate matter with a size of less than 2.5 micrometres (also called microns). It is one of the major components of smog. When inhaled deeply into the lungs, even small amounts of PM2.5 can cause serious health problems. It can also damage vegetation and structures, contribute to haze and reduce visibility.
Key results
- In 2023, PM2.5 emissions were 1 370 kilotonnes (kt); this is 15% lower than in 1990
- Emissions from dust and fires (for example, road dust, dust from construction operations and prescribed burningFootnote 10 ) accounted for the majority of PM2.5 emissions, reaching 63% (865 kt) of total national emissions in 2023
- These emissions increased by 68% (352 kt) between 1990 and 2023, the majority of the increase coming from dust from construction operations, specifically non-residential construction, and unpaved roads
Total fine particulate matter emissions by source, Canada, 1990 to 2023

Data table for the long description
Year | Dust and fires (emissions in kilotonnes) |
Agriculture (livestock, crop production and fertilizer) (emissions in kilotonnes) |
Other sources (emissions in kilotonnes) |
Home firewood burning (emissions in kilotonnes) |
Total emissions (emissions in kilotonnes) |
---|---|---|---|---|---|
1990 | 513.6 | 675.2 | 318.6 | 101.6 | 1 609.0 |
1991 | 502.8 | 667.8 | 293.4 | 102.4 | 1 566.5 |
1992 | 480.1 | 653.0 | 285.1 | 107.9 | 1 526.2 |
1993 | 502.1 | 638.7 | 279.7 | 108.5 | 1 529.1 |
1994 | 533.8 | 624.3 | 278.0 | 105.6 | 1 541.8 |
1995 | 547.2 | 610.1 | 276.3 | 103.3 | 1 536.8 |
1996 | 547.1 | 596.3 | 269.5 | 105.7 | 1 518.7 |
1997 | 575.8 | 582.5 | 265.3 | 104.0 | 1 527.7 |
1998 | 586.5 | 568.9 | 257.4 | 83.2 | 1 496.0 |
1999 | 588.5 | 555.3 | 258.2 | 80.3 | 1 482.4 |
2000 | 591.3 | 541.9 | 256.5 | 81.0 | 1 470.7 |
2001 | 622.1 | 528.7 | 234.5 | 69.5 | 1 454.9 |
2002 | 603.4 | 508.9 | 210.2 | 66.9 | 1 389.4 |
2003 | 627.6 | 489.2 | 204.1 | 62.7 | 1 383.5 |
2004 | 620.7 | 469.0 | 198.0 | 66.2 | 1 353.9 |
2005 | 650.8 | 449.5 | 196.1 | 67.9 | 1 364.3 |
2006 | 640.8 | 429.9 | 170.1 | 66.2 | 1 307.1 |
2007 | 667.6 | 416.6 | 164.6 | 77.5 | 1 326.5 |
2008 | 712.7 | 403.1 | 155.9 | 77.4 | 1 349.2 |
2009 | 696.6 | 389.8 | 139.8 | 78.1 | 1 304.2 |
2010 | 739.4 | 376.8 | 142.9 | 69.1 | 1 328.1 |
2011 | 766.7 | 363.5 | 137.3 | 73.3 | 1 340.9 |
2012 | 812.1 | 366.6 | 133.9 | 69.3 | 1 381.9 |
2013 | 840.2 | 369.4 | 129.1 | 75.4 | 1 414.2 |
2014 | 857.9 | 372.3 | 125.6 | 75.6 | 1 431.4 |
2015 | 816.5 | 375.3 | 119.9 | 72.8 | 1 384.5 |
2016 | 763.9 | 378.3 | 114.5 | 68.8 | 1 325.5 |
2017 | 776.6 | 374.1 | 119.7 | 69.0 | 1 339.4 |
2018 | 818.9 | 369.9 | 117.9 | 71.2 | 1 378.0 |
2019 | 842.4 | 365.8 | 116.4 | 68.3 | 1 392.9 |
2020 | 743.9 | 361.8 | 112.7 | 58.2 | 1 276.5 |
2021 | 783.5 | 357.5 | 118.7 | 52.2 | 1 311.9 |
2022 | 810.2 | 353.0 | 111.3 | 55.4 | 1 329.9 |
2023 | 865.3 | 348.3 | 105.0 | 51.3 | 1 369.8 |
Year | Dust and fires (emissions in kilotonnes) |
Agriculture (livestock, crop production and fertilizer) (emissions in kilotonnes) |
Home firewood burning (emissions in kilotonnes) | Ore and mineral industries (emissions in kilotonnes) |
Miscellaneous (emissions in kilotonnes) |
Manufacturing (emissions in kilotonnes) |
Off-road vehicles and mobile equipment (emissions in kilotonnes) |
Oil and gas industry (emissions in kilotonnes) |
Transportation (road, rail, air and marine) (emissions in kilotonnes) |
Building heating and energy generation (emissions in kilotonnes) |
---|---|---|---|---|---|---|---|---|---|---|
1990 | 513.6 | 675.2 | 101.6 | 54.3 | 13.9 | 114.1 | 36.0 | 11.8 | 33.4 | 4.6 |
1991 | 502.8 | 667.8 | 102.4 | 51.5 | 12.0 | 103.2 | 32.6 | 12.4 | 31.8 | 4.6 |
1992 | 480.1 | 653.0 | 107.9 | 49.3 | 12.0 | 99.9 | 31.6 | 12.6 | 32.2 | 4.7 |
1993 | 502.1 | 638.7 | 108.5 | 49.2 | 12.3 | 100.6 | 32.9 | 12.8 | 32.3 | 4.9 |
1994 | 533.8 | 624.3 | 105.6 | 51.0 | 12.7 | 100.5 | 34.1 | 13.7 | 33.9 | 4.9 |
1995 | 547.2 | 610.1 | 103.3 | 50.7 | 13.2 | 101.5 | 34.4 | 14.0 | 34.6 | 4.9 |
1996 | 547.1 | 596.3 | 105.7 | 52.6 | 13.2 | 93.2 | 35.5 | 14.1 | 34.5 | 5.2 |
1997 | 575.8 | 582.5 | 104.0 | 53.0 | 13.6 | 85.3 | 37.4 | 14.4 | 34.2 | 5.0 |
1998 | 586.5 | 568.9 | 83.2 | 50.6 | 14.4 | 80.2 | 37.1 | 16.1 | 32.5 | 4.6 |
1999 | 588.5 | 555.3 | 80.3 | 50.1 | 15.0 | 79.8 | 37.8 | 13.7 | 33.2 | 4.8 |
2000 | 591.3 | 541.9 | 81.0 | 51.2 | 15.5 | 74.8 | 39.0 | 13.5 | 32.0 | 5.3 |
2001 | 622.1 | 528.7 | 69.5 | 47.4 | 15.8 | 64.0 | 37.3 | 13.4 | 30.1 | 5.0 |
2002 | 603.4 | 508.9 | 66.9 | 37.3 | 16.0 | 55.3 | 35.7 | 13.9 | 29.5 | 5.2 |
2003 | 627.6 | 489.2 | 62.7 | 37.5 | 16.3 | 53.1 | 34.8 | 12.5 | 31.1 | 5.6 |
2004 | 620.7 | 469.0 | 66.2 | 35.9 | 16.8 | 50.6 | 33.8 | 11.8 | 31.5 | 5.3 |
2005 | 650.8 | 449.5 | 67.9 | 41.1 | 17.1 | 44.9 | 32.7 | 12.2 | 32.0 | 5.2 |
2006 | 640.8 | 429.9 | 66.2 | 39.3 | 17.3 | 29.0 | 30.1 | 11.6 | 30.6 | 4.9 |
2007 | 667.6 | 416.6 | 77.5 | 37.7 | 17.4 | 27.1 | 27.8 | 11.3 | 29.8 | 5.2 |
2008 | 712.7 | 403.1 | 77.4 | 35.9 | 17.8 | 24.3 | 26.1 | 9.8 | 28.7 | 5.1 |
2009 | 696.6 | 389.8 | 78.1 | 30.1 | 17.9 | 20.2 | 23.3 | 9.0 | 27.1 | 5.0 |
2010 | 739.4 | 376.8 | 69.1 | 33.9 | 17.6 | 19.6 | 25.3 | 8.9 | 26.1 | 4.8 |
2011 | 766.7 | 363.5 | 73.3 | 32.9 | 16.8 | 20.0 | 25.7 | 9.3 | 22.3 | 5.0 |
2012 | 812.1 | 366.6 | 69.3 | 35.1 | 16.9 | 19.4 | 24.2 | 9.8 | 19.8 | 4.6 |
2013 | 840.2 | 369.4 | 75.4 | 31.9 | 16.7 | 19.6 | 23.4 | 10.5 | 18.3 | 4.8 |
2014 | 857.9 | 372.3 | 75.6 | 31.6 | 16.1 | 18.7 | 21.3 | 12.4 | 16.4 | 4.9 |
2015 | 816.5 | 375.3 | 72.8 | 30.2 | 15.2 | 18.7 | 21.9 | 11.3 | 13.6 | 4.8 |
2016 | 763.9 | 378.3 | 68.8 | 30.0 | 15.2 | 17.2 | 21.1 | 10.4 | 11.6 | 4.9 |
2017 | 776.6 | 374.1 | 69.0 | 33.8 | 15.3 | 17.4 | 21.7 | 11.7 | 10.7 | 5.1 |
2018 | 818.9 | 369.9 | 71.2 | 32.7 | 15.3 | 17.3 | 21.0 | 11.8 | 10.7 | 5.3 |
2019 | 842.4 | 365.8 | 68.3 | 34.5 | 15.4 | 16.5 | 19.6 | 11.7 | 9.9 | 5.4 |
2020 | 743.9 | 361.8 | 58.2 | 35.1 | 15.5 | 16.6 | 16.6 | 12.2 | 8.4 | 5.0 |
2021 | 783.5 | 357.5 | 52.2 | 36.5 | 15.6 | 19.9 | 16.3 | 14.4 | 8.5 | 4.8 |
2022 | 810.2 | 353.0 | 55.4 | 34.7 | 15.7 | 15.1 | 15.2 | 14.4 | 8.3 | 5.1 |
2023 | 865.3 | 348.3 | 51.3 | 31.2 | 15.8 | 14.8 | 14.4 | 13.0 | 8.3 | 4.7 |
Note: The numbers have been rounded off and their sum may not correspond to the total.
Download data file (Excel/CSV; 4.10 kB)
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation. The category "other sources" includes emissions from ore and mineral industries, transportation (road, rail, air and marine), manufacturing, off-road vehicles and mobile equipment, the oil and gas industry, building heating and energy generation, electric utilities, incineration and wastes, paints and solvents, and other miscellaneous sources. Consult Table 1 in the Data sources and methods for a complete list of the air pollutant emissions sources included under each category. The interactive figures provide a dynamic and customizable format to explore the emissions.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
In 2023, 89% of PM2.5 emissions came from open source emissions, such as dust and prescribed fires, and agriculture (livestockFootnote 11 , crop production and fertilizer). PM2.5 emissions does not include emissions from natural sources such as wildfires and vegetation. In general, these open source emissions are spread over large geographical areas, are highly dependent on weather conditions (for example, wind and rain) and are located outside of urban areas. As such, exposure of PM2.5 to most people in Canada is not driven by emissions from open sources, but rather from PM2.5 that forms when pollutants react in the atmosphere.
The remaining 11% of PM2.5 emissions in 2023 came from home firewood burning (51 kt or 4%) and other sources, including:
- ore and mineral industries, representing 2% (31 kt) of the emissions
- manufacturing and miscellaneous sources, such as emissions from commercial cooking, each representing about 1% (15 kt and 16 kt) of emissions
- off-road vehicles and mobile equipment, representing about 1% (16 kt)
- the oil and gas industry, representing about 1% (13 kt)
- transportation (road, rail, air and marine), representing less than 1% (7 kt)
- other emissions (less than 1%; 7 kt) coming from building heating and energy generation, electric utilities, incineration and waste, and the use of paints and solvents
Many of the sources above, despite representing a small proportion of national emissions, can have a disproportionate health impact on the population because they are generally concentrated in or near populated areas.
The decreases in PM2.5 emissions between 1990 and 2023 are mainly attributable to emission reductions from agriculture (crop production) (327 kt or 48%), manufacturing (99 kt or 87%) and home firewood burning (50 kt or 50%). These reductions outweigh the increase in emissions from dust and fires (352 kt or 68%), specifically road dust and dust from construction operations, over the period. The adoption of conservation practices in crop production and the use of new fireplace inserts, furnaces and stoves that burn more efficiently to control home firewood burning emissions were the main drivers leading to the reductions.
Fine particulate matter emissions by province and territory
Key results
- In 2023, Saskatchewan and Alberta emitted the most PM2.5, representing 51% (695 kt) of total national emissions
- Between 1990 and 2023,
- the largest decrease was observed in Saskatchewan with 147 kt (29%)
- PM2.5 emissions increased by 6 kt (4%) in Quebec, 1 kt (50%) in Yukon and 4 kt (81%) in Northwest Territories and Nunavut
Fine particulate matter emissions by province and territory, Canada, 1990 and 2023

Data table for the long description
Province or territory | 1990 (emissions in kilotonnes) |
2005 (emissions in kilotonnes) |
2023 (emissions in kilotonnes) |
1990, excluding open sources [A] (emissions in kilotonnes) |
2005, excluding open sources [A] (emissions in kilotonnes) |
2023, excluding open sources [A] (emissions in kilotonnes) |
---|---|---|---|---|---|---|
Newfoundland and Labrador | 19.9 | 19.5 | 17.2 | 11.3 | 8.1 | 3.1 |
Prince Edward Island | 4.8 | 4.3 | 4.3 | 1.9 | 1.6 | 0.9 |
Nova Scotia | 27.3 | 23.7 | 18.8 | 16.2 | 11.7 | 4.4 |
New Brunswick | 24.7 | 21.1 | 14.8 | 15.6 | 12.0 | 4.3 |
Quebec | 151.1 | 140.0 | 157.3 | 82.1 | 64.4 | 47.7 |
Ontario | 236.3 | 209.8 | 227.8 | 97.8 | 66.0 | 37.8 |
Manitoba | 103.2 | 93.7 | 92.7 | 12.5 | 9.1 | 4.3 |
Saskatchewan | 505.9 | 384.4 | 359.2 | 21.2 | 17.1 | 10.1 |
Alberta | 361.7 | 357.3 | 335.9 | 66.0 | 32.7 | 23.6 |
British Columbia | 166.8 | 99.7 | 129.7 | 93.7 | 39.6 | 18.8 |
Yukon | 2.6 | 3.2 | 3.9 | 0.4 | 0.3 | 0.2 |
Northwest Territories | 4.7[B] | 5.4 | 4.2 | 1.6[B] | 0.8 | 0.6 |
Nunavut[B] | n/a | 2.3 | 4.3 | n/a | 0.6 | 0.3 |
Note: [A] Open sources include emissions associated with dust and fires and agriculture (livestock, crop production and fertilizer). [B]1990 emissions data for the Northwest Territories include emissions for Nunavut, which was part of the Northwest Territories until 1999. n/a = not applicable.
Download data file (Excel/CSV; 1.73 kB)
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires and from vegetation.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
In 2023, Saskatchewan was the highest emitting province of PM2.5 emissions, accounting for 26% (359 kt) of total national emissions. Agriculture (specifically wind erosion) and dust and fires (specifically dust from unpaved roads) were the largest sources of PM2.5 emissions in the province.
Alberta ranked second in 2023, with 25% (336 kt) of total national PM2.5 emissions. Dust and fires (specifically dust from unpaved roads) were the largest sources, with agriculture (livestock, crop production and fertilizer) being the second-largest source of PM2.5, specifically from wind erosion, tillage practices and harvesting.
Ontario ranked third, with 17% (228 kt), and Quebec ranked fourth with 11% (157 kt). For these 2 provinces, dust and fires were the largest source of emissions.
The exclusion of emissions from dust and fires and agriculture (livestock, crop production and fertilizer) provide a different breakdown of PM2.5 emissions in each province and territory. With these emissions removed, Quebec becomes the largest emitting province of PM2.5 in 2023, representing 31% (48 kt) of total emissions (156 kt); home firewood burning being the largest emitting source. Ontario ranks second with 24% (38 kt) of emissions, with home firewood burning and ore and mineral industries equally being the largest sources of emissions. Alberta and British Columbia rank third and fourth, representing 15% (24 kt) (the largest source being from the oil and gas industry) and 12% (19 kt) (the largest source being from the ore and mineral industries) of emissions. Between 1990 and 2023, with dust, fires and agriculture excluded, all of the provinces and territories experienced emissions reductions between 80% (British Columbia, with a 75 kt emission reduction; the primary source of emissions being from manufacturing) and 41% (Northwest Territories and Nunavut, with a 0.6 kt emission reduction; with off-road vehicles and mobile equipment being the largest sources of emissions).
Fine particulate matter emissions by facilities
The National Pollutant Release Inventory provides detailed information on air pollutant emissions from industrial and commercial facilities that meet its reporting criteria.
The Canadian Environmental Sustainability Indicators provide access to this information through an interactive map. The map allows you to explore PM2.5 emissions from individual facilities.
Key results
- In 2023, 4 921 facilities across Canada reported PM2.5 emissions representing 4% of total national emissions. Of these facilities:
- 2 737 facilities reported emissions under 1 tonne (t)
- 2 091 facilities reported emissions between 1 to 100 t
- 93 facilities reported emissions of 100 t or more located in Quebec (22), British Columbia (18), Ontario (18), Alberta (16), Saskatchewan (9), Newfoundland and Labrador (5), New Brunswick (2), Manitoba (2), and Nunavut (1))
Fine particulate matter by reporting facilities, Canada, 2023

Long description
The map of Canada shows the amount of fine particulate matter emissions in tonnes in 2023 by reporting facility. The categories are: 0 to 0.5 tonne, 0.5 to 1 tonne, 1 to 5 tonnes, 5 to 25 tonnes, 25 to 100 tonnes and 100 tonnes or more.
Source: Environment and Climate Change Canada (2025) National Pollutant Release Inventory.
Navigate data using the interactive map
Black carbon
Black carbon is a component of PM2.5 and is generated by the incomplete combustion of fossil fuels and biomass. It is a short-lived climate pollutant, contributing to climate warming and linked to adverse human health effects. Reductions in black carbon emissions have near-term climate and health and environmental benefits such as improving air quality, slowing climate warming, reducing snow and ice melts, increasing crop yields and reducing negative impacts to ecosystem health and human health.
Key results
- Emissions of black carbon were 22 kt in 2023, a decrease of 40% from 2013
- In 2023, 3 sectors accounted for 76% of national black carbon emissions:
- off-road vehicles and mobile equipment
- home firewood burning
- transportation (road, rail, air and marine)
Total black carbon emissions by source, Canada, 2013 to 2023

Data table for the long description
Year | Off-road vehicles and mobile equipment (emissions in kilotonnes) |
Transportation (road, rail, air and marine) (emissions in kilotonnes) |
Home firewood burning (emissions in kilotonnes) |
Oil and gas industry (emissions in kilotonnes) |
Other sources (emissions in kilotonnes) |
Building heating and energy generation (emissions in kilotonnes) |
Total emissions (emissions in kilotonnes) |
---|---|---|---|---|---|---|---|
2013 | 13.6 | 10.1 | 6.8 | 2.6 | 1.9 | 1.0 | 36.0 |
2014 | 12.4 | 9.1 | 6.8 | 2.6 | 1.9 | 1.0 | 34.1 |
2015 | 13.1 | 7.6 | 6.6 | 2.7 | 1.6 | 1.0 | 32.6 |
2016 | 12.3 | 6.2 | 6.3 | 2.4 | 1.5 | 1.2 | 29.7 |
2017 | 12.9 | 5.7 | 6.4 | 2.5 | 1.5 | 1.2 | 30.2 |
2018 | 12.5 | 5.7 | 6.5 | 2.5 | 1.4 | 1.2 | 29.9 |
2019 | 11.5 | 5.3 | 6.1 | 2.5 | 1.5 | 1.2 | 28.0 |
2020 | 9.5 | 4.6 | 5.0 | 2.5 | 1.5 | 1.2 | 24.2 |
2021 | 9.1 | 4.6 | 4.3 | 2.7 | 1.5 | 1.1 | 23.3 |
2022 | 8.3 | 4.4 | 4.6 | 2.6 | 1.8 | 1.1 | 22.9 |
2023 | 7.7 | 4.4 | 4.3 | 2.5 | 1.7 | 1.1 | 21.6 |
Note: The numbers have been rounded off and their sum may not correspond to the total.
Download data file (Excel/CSV; 1.81 kB)
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires. The chart includes emissions from the most significant sources of black carbon. "Other sources" includes emissions from ore and mineral industries, manufacturing, electric utilities and agriculture. Consult Table 1 in the Data sources and methods for more details. The interactive figures provide a dynamic and customizable format to explore the emissions.
Source: Environment and Climate Change Canada (2025) Canada's Black Carbon Emissions Inventory.
In 2023, off-road vehicles and mobile equipment (for example, lawn and garden equipment, recreational vehicles, excavators, graders) accounted for the largest proportion of total national emissions, representing 35% (8 kt) of emissions. Home firewood burning and transportation (road, rail, air and marine) were also large contributors, each representing 20% (4 kt) of total national emissions. The remaining emissions came from the oil and gas industry, building heating and energy generation and other sources (such as the ore and mineral industries).
Black carbon emissions by province and territory
Key results
- In 2023, 3 provinces, Alberta, Quebec and Ontario, accounted for 62% (13 kt) of total national black carbon emissions
- Between 2013 and 2023:
- all provinces and territories experienced reductions in black carbon emissions between 18% to 68%, with the main sources of national reductions coming from the off-road vehicles and mobile equipment (44%, 5 937 kt), transportation (road, rail, air and marine) (56%, 5 685 kt) and home firewood burning (37%, 2 549 kt) sectors
- Alberta, Ontario and Quebec experienced the largest reductions in emissions with decreases of 2.8 kt each. For these 3 provinces, the reductions were mainly attributable to lower emissions from transportation (road, rail, air and marine) and off-road vehicles and mobile equipment
Black carbon emissions by province and territory, Canada, 2013 and 2023

Data for the long description
Province or territory | 2013 (emissions in kilotonnes) |
2023 (emissions in kilotonnes) |
---|---|---|
Newfoundland and Labrador | 0.8 | 0.5 |
Prince Edward Island | 0.2 | 0.1 |
Nova Scotia | 1.2 | 0.5 |
New Brunswick | 1.3 | 0.4 |
Quebec | 7.2 | 4.4 |
Ontario | 6.9 | 4.1 |
Manitoba | 1.5 | 0.8 |
Saskatchewan | 4.3 | 2.9 |
Alberta | 7.8 | 5.0 |
British Columbia | 3.9 | 2.5 |
Yukon | 0.1 | 0.1 |
Northwest Territories | 0.5 | 0.2 |
Nunavut | 0.2 | 0.1 |
Download data file (Excel/CSV; 915 B)
How this indicator was calculated
Note: The indicator reports air pollutant emissions from human activities only. It does not include emissions from natural sources such as forest fires.
Source: Environment and Climate Change Canada (2025) Canada's Black Carbon Emissions Inventory.
Alberta, Ontario and Quebec had the highest black carbon emissions in 2023:
- Emissions in Alberta primarily came from 3 sources: off-road vehicles and mobile equipment (2 kt, 41%), the oil and gas industry (1.7 kt, 34%) and transportation (road, rail, air and marine) (0.8 kt, 16%), representing 91% (4.5 kt) of the emissions
- Ontario's emissions also came primarily from off-road vehicles and mobile equipment (1.4 kt, 34%), and transportation (road, rail, air and marine) (1.0 kt, 24%) as well as home firewood burning (0.9 kt, 21%), representing 78% (3.2 kt) of emissions in the province
- In Quebec, emissions came primarily from home firewood burning (53%, 2.3 kt), as well as from off-road vehicles and mobile equipment (23%, 1 kt), representing 76% (3.3 kt) of emissions
By sector
Oil and gas industry
Air pollutant emissions from the oil and gas industry
The oil and gas sector is an important contributor to air pollutant emissions. Most emissions from the oil and gas sector come from upstream activities (i.e., exploration, drilling, production and field processing) and to a lesser extent from downstream activities (i.e., refining, storage and distribution). Air pollutants emitted by this sector contribute to the formation of fine particulate matter (PM2.5), ozone (O3), smog and acid rain. They also adversely affect human health, the environment, and the economy. Footnote 12
Key results
- In 2023, the oil and gas industry was a major contributor to total national emissions of sulphur oxides (SOX) (43%), volatile organic compounds (VOCs) (40%), nitrogen oxides (NOX) (37%) and carbon monoxide (CO) (12%)
- The oil and gas industry is also a source of emissions of fine particulate matter (PM2.5) and ammonia (NH3). However, in 2023, it made up only 1% of the respective total emissions of these pollutants
Contribution of the oil and gas industry to total air pollutant emissions by activity type, Canada, 2023

Data table for the long description
Activity type | Sulphur oxides (percentage of national emissions) |
Volatile organic compounds (percentage of national emissions) |
Nitrogen oxides (percentage of national emissions) |
Carbon monoxide (percentage of national emissions) |
Fine particulate matter (percentage of national emissions) |
Ammonia (percentage of national emissions) |
---|---|---|---|---|---|---|
Upstream oil and gas | 37.3 | 37.8 | 35.2 | 11.2 | 0.8 | 0.5 |
Downstream oil and gas | 6.2 | 1.7 | 1.6 | 0.7 | 0.1 | <0.1 |
Activity type | Sulphur oxides (emissions in kilotonnes) |
Volatile organic compounds (emissions in kilotonnes) |
Nitrogen oxides (emissions in kilotonnes) |
Carbon monoxide (emissions in kilotonnes) |
Fine particulate matter (emissions in kilotonnes) |
Ammonia (emissions in kilotonnes) |
---|---|---|---|---|---|---|
Upstream oil and gas | 226.6 | 517.0 | 431.8 | 505.6 | 11.5 | 2.6 |
Downstream oil and gas | 37.7 | 23.6 | 19.8 | 32.9 | 1.5 | <0.1 |
Download data file (Excel/CSV; 1.40 kB)
How this indicator was calculated
Note: Fine particulate matter and ammonia are not shown in the chart due to their low share (≤ 1%) of total emissions in 2023. In the oil and gas industry, upstream activities include exploration, drilling, production and field processing and downstream activities include refining, storage and distribution.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
In 2023, the oil and gas industry was the largest contributor to the total national emissions of SOX, VOCs and NOX. It was also the third-largest contributor to emissions of CO.
Most emissions from the oil and gas industry came from upstream activities compared to downstream activities. In 2023, 98% of NH3, 96% of VOC and NOX, 94% of CO, 88% of PM2.5 and 86% of SOX emissions from the oil and gas sector were from upstream activities.
Changes in emissions from the oil and gas industry
Key results
- Emissions of SOX and VOC emissions decreased 51% and 11% , respectively, between 1990 and 2023
- CO and NOX increased by 61% and 31%, respectively, over that period
Changes in emissions of key air pollutants from the oil and gas industry, Canada, 1990 to 2023

Data table for the long description
Year | Carbon monoxide (percentage change from 1990 level) |
Nitrogen oxides (percentage change from 1990 level) |
Volatile organic compounds (percentage change from 1990 level) |
Sulphur oxides (percentage change from 1990 level) |
---|---|---|---|---|
1990 | 0 | 0 | 0 | 0 |
1991 | -3 | -2 | -1 | 1 |
1992 | 1 | 3 | 2 | 8 |
1993 | 8 | 10 | 6 | 14 |
1994 | 19 | 19 | 9 | 13 |
1995 | 21 | 24 | 11 | 12 |
1996 | 25 | 28 | 16 | 12 |
1997 | 40 | 40 | 13 | 3 |
1998 | 45 | 44 | 16 | -2 |
1999 | 49 | 49 | 8 | -4 |
2000 | 32 | 33 | 10 | -4 |
2001 | 40 | 31 | 11 | -7 |
2002 | 50 | 32 | 13 | -13 |
2003 | 58 | 43 | 12 | -11 |
2004 | 50 | 24 | 8 | -13 |
2005 | 48 | 24 | 8 | -14 |
2006 | 50 | 24 | 4 | -21 |
2007 | 56 | 31 | 3 | -25 |
2008 | 61 | 34 | 5 | -29 |
2009 | 57 | 32 | -3 | -31 |
2010 | 55 | 30 | -6 | -37 |
2011 | 58 | 33 | -8 | -39 |
2012 | 58 | 31 | 0 | -38 |
2013 | 68 | 32 | 8 | -41 |
2014 | 63 | 35 | 14 | -46 |
2015 | 65 | 35 | 10 | -51 |
2016 | 60 | 33 | -1 | -54 |
2017 | 64 | 35 | 2 | -52 |
2018 | 69 | 37 | 5 | -50 |
2019 | 61 | 36 | 1 | -50 |
2020 | 53 | 29 | -13 | -55 |
2021 | 61 | 28 | -13 | -51 |
2022 | 56 | 29 | -12 | -48 |
2023 | 61 | 31 | -11 | -51 |
Year | Carbon monoxide (emissions in kilotonnes) |
Nitrogen oxides (emissions in kilotonnes) |
Volatile organic compounds (emissions in kilotonnes) |
Sulphur oxides (emissions in kilotonnes) |
---|---|---|---|---|
1990 | 334 | 344 | 607 | 536 |
1991 | 324 | 337 | 602 | 542 |
1992 | 338 | 353 | 616 | 581 |
1993 | 361 | 378 | 644 | 608 |
1994 | 398 | 410 | 662 | 605 |
1995 | 405 | 426 | 673 | 598 |
1996 | 417 | 438 | 701 | 597 |
1997 | 467 | 482 | 688 | 553 |
1998 | 485 | 494 | 701 | 523 |
1999 | 497 | 511 | 654 | 516 |
2000 | 442 | 456 | 668 | 513 |
2001 | 466 | 451 | 672 | 498 |
2002 | 500 | 452 | 684 | 468 |
2003 | 529 | 493 | 677 | 476 |
2004 | 501 | 427 | 656 | 468 |
2005 | 493 | 428 | 652 | 462 |
2006 | 502 | 427 | 630 | 424 |
2007 | 522 | 450 | 627 | 402 |
2008 | 539 | 460 | 634 | 378 |
2009 | 523 | 455 | 587 | 372 |
2010 | 518 | 445 | 569 | 339 |
2011 | 527 | 457 | 557 | 328 |
2012 | 529 | 450 | 608 | 331 |
2013 | 561 | 454 | 658 | 315 |
2014 | 544 | 462 | 694 | 287 |
2015 | 552 | 464 | 666 | 261 |
2016 | 533 | 456 | 599 | 246 |
2017 | 547 | 464 | 616 | 255 |
2018 | 564 | 470 | 638 | 266 |
2019 | 537 | 468 | 614 | 267 |
2020 | 510 | 444 | 526 | 244 |
2021 | 536 | 439 | 525 | 263 |
2022 | 522 | 443 | 533 | 277 |
2023 | 539 | 452 | 541 | 264 |
Download data file (Excel/CSV; 2.08 kB)
How this indicator was calculated
Note: Fine particulate matter and ammonia are not shown in the chart due to their low share (≤ 1%) of total emissions in 2023.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
The increases in CO and NOX emissions between 1990 and 2023 were due to growth in oil and gas production (the upstream sector of the industry), as emissions from the downstream sector declined due to facility closures during that period.Footnote 13 This increase is in part explained by the fact that crude oil production in Canada more than doubled since 1990. The growth was mostly driven by a rapid increase in oil sands production, particularly by in-situ oil sands extraction. During the same period, production of natural gas from unconventional sources, such as those requiring the use of multi-stage fracturing techniques, also increased significantly.
The decrease in SOX emissions was mostly the result of a decrease in emissions from oil sands mining, extraction and upgrading, and natural gas production and processing, attributed to better emission control technologies.
For VOCs, the recent decline was partly due to reductions in light/medium crude oil production and petroleum refining, storage and distribution. The decrease in VOC emissions is also driven by reduced venting emissions from crude oil production since 2014 (over this period, operators took measures to conserve gas under provincial directives, even prior to the implementation of federal and provincial regulations). In addition, federal and provincial regulations to reduce fugitive emissions from the sector came into effect in 2020, contributing further to the decline.
Transportation, off-road vehicles and mobile equipment
Air pollutant emissions from transportation, off-road vehicles and mobile equipment
Transportation, off-road vehicles and mobile equipment are among the largest sources of air pollutants in Canada. Burning fossil fuels to power vehicles and engines causes emissions of many air pollutants. These air pollutants lead to the formation of fine particulate matter, ozone, smog and acid rain. These pollutants and resulting impacts also adversely affect human health, the environment and the economy.
Key results
- In 2023, transportation, off-road vehicles and mobile equipment accounted for more than half (60%) of total national emissions of carbon monoxide (CO), 38% of nitrogen oxides (NOX) and 14% of total emissions of volatile organic compounds (VOCs)
- While also a source of emissions for fine particulate matter (PM2.5), ammonia (NH3) and sulphur oxides (SOX), the sectors represented less than 2% of total national emissions, respectively
Contribution of transportation, off-road vehicles and mobile equipment to total air pollutant emissions by transportation mode, Canada, 2023

Data table for the long description
Transportation mode | Carbon monoxide (percentage of national emissions) |
Nitrogen oxides (percentage of national emissions) |
Volatile organic compounds (percentage of national emissions) |
Fine particulate matter (percentage of national emissions) |
Sulphur oxides (percentage of national emissions) |
Ammonia (percentage of national emissions) |
---|---|---|---|---|---|---|
Passenger cars and motorcycles | 7.7 | 1.0 | 1.6 | <0.1 | <0.1 | 0.4 |
Passenger light trucks | 10.8 | 1.8 | 1.9 | 0.1 | 0.1 | 0.4 |
Large trucks and buses | 2.7 | 10.1 | 0.8 | 0.3 | <0.1 | 0.2 |
Air, marine and rail travel | 1.0 | 11.7 | 0.6 | 0.2 | 0.3 | <0.1 |
Off-road vehicles and equipment, tire wear and brake lining | 37.9 | 13.4 | 9.3 | 1.1 | <0.1 | 0.1 |
Transportation mode | Carbon monoxide (emissions in kilotonnes) |
Nitrogen oxides (emissions in kilotonnes) |
Volatile organic compounds (emissions in kilotonnes) |
Fine particulate matter (emissions in kilotonnes) |
Sulphur oxides (emissions in kilotonnes) |
Ammonia (emissions in kilotonnes) |
---|---|---|---|---|---|---|
Passenger cars and motorcycles | 348.2 | 12.0 | 22.4 | 0.4 | 0.2 | 2.0 |
Passenger light trucks | 485.8 | 22.2 | 25.6 | 0.8 | 0.4 | 3.3 |
Large trucks and buses | 123.3 | 123.9 | 10.3 | 3.5 | 0.2 | 1.2 |
Air, marine and rail travel | 43.8 | 144.2.7 | 7.9 | 2.3 | 2.1 | <0.1 |
Off-road vehicles and equipment, tire wear and brake lining | 1 712.7 | 164.6 | 127.6 | 15.7 | 0.2 | 0.4 |
Download data file (Excel/CSV; 2.13 kB)
How this indicator was calculated
Note: "Passenger cars and motorcycles" include cars powered by motor gasoline, diesel, liquefied petroleum gas and compressed natural gas engines as well as all types of motorcycles. "Passenger light trucks" include light-duty trucks powered by motor gasoline, diesel, liquefied petroleum gas and compressed natural gas engines. "Large trucks and buses" include heavy-duty trucks powered by motor gasoline, diesel, liquefied petroleum gas and compressed natural gas engines.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
The contribution of each transportation mode to emissions of different air pollutants is in large part explained by the mix of fuels used in these modes.
Large trucks and buses, and rail and marine travel rely predominantly on diesel fuel. Aviation relies on turbo aviation fuel. These transportation modes are the largest sources of NOX transportation-related emissions accounting for 22% (268 kilotonnes [kt]) of total NOX emissions.
Passenger cars and light trucks mostly use gasoline and are an important source of pollutants, especially in urban centres. In 2023, emissions from passenger cars, motorcycles and light trucks amounted to 834 kt of CO, 34 kt of NOX and 48 kt of VOCs. These emissions represented 18%, 3% and 4% of all emissions of these pollutants respectively.
Off-road vehicles and equipmentFootnote 14 are also a significant source of pollution. Their combined emissions make up 38%, 13% and 9% of the total emissions of CO, NOX and VOCs, respectively. Emissions mostly come from household use of gasoline- or diesel-powered recreational and lawn and garden equipment, and from the operation of agricultural, construction and mining equipment. In 2023, commercial equipment use produced higher emissions of NOX, PM2.5, SOX, and NH3 compared to recreational and lawn and garden equipment use. However, emissions of CO and VOCs were greater from recreational and lawn and garden equipment use than from commercial use of equipment.
Changes in emissions from transportation, off-road vehicles and mobile equipment
Key results
- Between 1990 and 2023, total emissions of NOX, VOCs and CO from transportation, off-road vehicles and mobile equipment decreased by 63%, 69% and 72%, respectively
- Since 2000, all 3 pollutants demonstrated the same downward trend in their emissions level
Changes in emissions of key air pollutants from transportation, off-road vehicles and mobile equipment, Canada, 1990 to 2023

Data table for the long description
Year | Nitrogen oxides (percentage change from 1990 level) |
Carbon monoxide (percentage change from 1990 level) |
Volatile organic compounds (percentage change from 1990 level) |
---|---|---|---|
1990 | 0 | 0 | 0 |
1991 | -3 | -5 | -2 |
1992 | 0 | -5 | 1 |
1993 | 6 | -5 | 5 |
1994 | 15 | -4 | 11 |
1995 | 19 | -2 | 20 |
1996 | 22 | -3 | 25 |
1997 | 26 | -4 | 28 |
1998 | 26 | -5 | 32 |
1999 | 25 | -7 | 33 |
2000 | 23 | -9 | 29 |
2001 | 16 | -11 | 27 |
2002 | 12 | -12 | 24 |
2003 | 8 | -18 | 18 |
2004 | 3 | -24 | 13 |
2005 | -1 | -31 | 5 |
2006 | -7 | -36 | -3 |
2007 | -10 | -45 | -11 |
2008 | -15 | -50 | -19 |
2009 | -22 | -52 | -25 |
2010 | -22 | -50 | -26 |
2011 | -29 | -55 | -34 |
2012 | -34 | -58 | -40 |
2013 | -37 | -60 | -44 |
2014 | -41 | -64 | -50 |
2015 | -45 | -66 | -54 |
2016 | -50 | -66 | -55 |
2017 | -51 | -67 | -58 |
2018 | -52 | -67 | -60 |
2019 | -54 | -68 | -62 |
2020 | -61 | -72 | -67 |
2021 | -62 | -71 | -68 |
2022 | -62 | -72 | -69 |
2023 | -63 | -72 | -69 |
Year | Nitrogen oxides (emissions in kilotonnes) |
Carbon monoxide (emissions in kilotonnes) |
Volatile organic compounds (emissions in kilotonnes) |
---|---|---|---|
1990 | 1 261.5 | 9 581.4 | 633.9 |
1991 | 1 227.9 | 9 136.4 | 622.3 |
1992 | 1 264.2 | 9 148.0 | 642.0 |
1993 | 1 335.9 | 9 084.1 | 667.5 |
1994 | 1 451.5 | 9 197.8 | 706.4 |
1995 | 1 500.5 | 9 411.6 | 759.3 |
1996 | 1 543.6 | 9 299.5 | 789.7 |
1997 | 1 593.4 | 9 186.7 | 813.4 |
1998 | 1 589.5 | 9 095.5 | 833.5 |
1999 | 1 574.7 | 8 910.2 | 842.2 |
2000 | 1 554.7 | 8 756.8 | 819.8 |
2001 | 1 469.4 | 8 559.0 | 805.2 |
2002 | 1 407.2 | 8 399.7 | 787.7 |
2003 | 1 357.0 | 7 811.5 | 746.4 |
2004 | 1 304.8 | 7 312.2 | 715.3 |
2005 | 1 251.3 | 6 646.7 | 664.5 |
2006 | 1 172.8 | 6 138.5 | 616.0 |
2007 | 1 131.3 | 5 252.0 | 563.6 |
2008 | 1 070.0 | 4 799.5 | 511.0 |
2009 | 979.6 | 4 571.2 | 475.0 |
2010 | 978.8 | 4 753.6 | 468.5 |
2011 | 895.9 | 4 273.6 | 416.3 |
2012 | 829.9 | 3 980.1 | 382.4 |
2013 | 792.9 | 3 844.0 | 358.1 |
2014 | 739.5 | 3 468.0 | 316.0 |
2015 | 691.6 | 3 272.1 | 294.2 |
2016 | 627.1 | 3 303.4 | 283.4 |
2017 | 621.7 | 3 198.1 | 266.6 |
2018 | 610.8 | 3 129.3 | 253.8 |
2019 | 578.0 | 3 065.2 | 240.8 |
2020 | 490.8 | 2 704.5 | 207.8 |
2021 | 483.2 | 2 780.5 | 204.5 |
2022 | 475.2 | 2 681.3 | 195.4 |
2023 | 467.0 | 2 713.9 | 193.8 |
Download data file (Excel/CSV; 2.09 kB)
How this indicator was calculated
Note: Fine particulate matter, sulphur oxides and ammonia are not shown in the chart due to their low share (≤ 5%) of total emissions in 2023.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
Pollutant emissions have decreased despite economic and population growth as well as growth in transport activities for the period between 1990 and 2023. This decrease is mainly attributable to the adoption of new regulations that lead to the gradual introduction of emission control technologies and clean fuel for vehicles.
Between 1990 and 2000, NOX emissions increased by 23%. It includes the increase in emissions from light trucks (116%), large trucks and buses (19%) and marine and air transportation (17 and 19%), which can be linked to economic and population growth during that time. From 2000 to 2023, new regulations contributed to a decrease in NOX emissions (33%, 71 kt) from light trucks (91%), large trucks and buses (72%) and emissions from rail travel (52%).
Transportation emissions are influenced by a variety of factors. These include population and economic growth, volume of passenger and freight travel, vehicle type, emission control technologies, transportation infrastructure, fuel efficiency and fuel type.
Electric utilities
Air pollutant emissions from the electric utilities
Electricity generation produces sulphur oxides (SOX) and nitrogen oxides (NOX). SOX and NOX are mostly emitted from power plants burning fossil fuels such as coal and, to a lesser extent, natural gas and diesel. These air pollutants contribute to the formation of fine particulate matter, ozone, smog and acid rain. They also adversely affect human health, the environment, and the economy.
Key results
- In 2023, electric utilities were the source of 22% and 7% of total national emissions of sulphur oxides (SOX) and nitrogen oxides (NOX), respectively
- Most of the air pollutant emissions from electric utilities come from burning coal
- Electric utilities are also a source of carbon monoxide (CO), volatile organic compounds (VOCs), fine particulate matter (PM2.5) and ammonia (NH3) emissions. However, they account for less than 1% of the total national emissions of these pollutants
Contribution of electric utilities to total air pollutant emissions by fuel source, Canada, 2023

Data table for the long description
Fuel source | Sulphur oxides (percentage of national emissions) |
Nitrogen oxides (percentage of national emissions) |
Carbon monoxide (percentage of national emissions) |
Fine particulate matter (percentage of national emissions) |
Volatile organic compounds (percentage of national emissions) |
Ammonia (percentage of national emissions) |
---|---|---|---|---|---|---|
Coal | 20.5 | 3.8 | 0.3 | <0.1 | <0.1 | n/a |
Natural gas | 0.2 | 2.0 | 0.4 | <0.1 | <0.1 | <0.1 |
Diesel | <0.1 | 0.9 | <0.1 | <0.1 | <0.1 | <0.1 |
Other sources | 1.5 | 0.6 | <0.1 | <0.1 | <0.1 | <0.1 |
Fuel source | Sulphur oxides (percentage of national emissions) |
Nitrogen oxides (percentage of national emissions) |
Carbon monoxide (percentage of national emissions) |
Fine particulate matter (percentage of national emissions) |
Volatile organic compounds (percentage of national emissions) |
Ammonia (percentage of national emissions) |
---|---|---|---|---|---|---|
Coal | 124.5 | 46.4 | 14.1 | 0.8 | 0.2 | n/a |
Natural gas | 1.3 | 25.1 | 16.0 | 0.3 | 1.2 | 0.3 |
Diesel | <0.1 | 11.3 | 2.8 | 0.2 | 0.1 | n/a |
Other sources | 9.0 | 7.2 | 5.7 | 0.5 | 0.2 | 0.1 |
Download data file (Excel/CSV; 1.55 kB)
Note: n/a = not available.
How this indicator was calculated
Note: Carbon monoxide, fine particulate matter, volatile organic compounds and ammonia are not shown in the chart due to their low share (≤ 1%) of total emissions in 2023. The indicator excludes emissions from industries that generate electricity and heat as a supporting activity rather than as their primary purpose. "Other sources" include fuel sources such as waste material and other uncategorized sources of electricity generation.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
In 2023, 92% of SOX and 51% of NOX emissions from electric utilities came from burning coal.
While generating electricity by burning fossil fuels causes air pollutant emissions, the use of non-fossil energy sources, such as hydroelectric, nuclear and other renewable sources to generate electricity, does not emit air pollutants.
A large share of the electricity generated in Canada comes from sources that do not directly emit air pollutants:
- 62% of electricity comes from hydro
- 13% comes from nuclear power plants
- 8% comes from non-hydroelectric renewable sources, such as wind, solar, tidal power and biomassFootnote 15
Changes in emissions from electric utilities
Key results
- Emissions of SOX and NOX from electric utilities declined by 78% and 65%, respectively, between 1990 and 2023
- Most of that decline occurred from 2005 onward
Changes in emissions of key air pollutants from electric utilities, Canada, 1990 to 2023

Data table for the long description
Year | Sulphur oxides (percentage change from 1990 level) |
Nitrogen oxides (percentage change from 1990 level) |
---|---|---|
1990 | 0 | 0 |
1991 | -4 | -2 |
1992 | -1 | 2 |
1993 | -12 | -5 |
1994 | -9 | -7 |
1995 | -14 | -3 |
1996 | -12 | 5 |
1997 | -4 | 12 |
1998 | -2 | 21 |
1999 | -3 | 19 |
2000 | 0 | 27 |
2001 | 1 | 22 |
2002 | 1 | 23 |
2003 | 2 | 14 |
2004 | -6 | 4 |
2005 | -16 | -1 |
2006 | -26 | -13 |
2007 | -20 | -7 |
2008 | -31 | -12 |
2009 | -38 | -15 |
2010 | -46 | -9 |
2011 | -53 | -22 |
2012 | -54 | -35 |
2013 | -55 | -37 |
2014 | -56 | -35 |
2015 | -59 | -41 |
2016 | -59 | -41 |
2017 | -60 | -44 |
2018 | -64 | -50 |
2019 | -67 | -51 |
2020 | -73 | -60 |
2021 | -73 | -61 |
2022 | -75 | -64 |
2023 | -78 | -65 |
Year | Sulphur oxides (emissions in kilotonnes) |
Nitrogen oxides (emissions in kilotonnes) |
---|---|---|
1990 | 618 | 257 |
1991 | 592 | 251 |
1992 | 611 | 263 |
1993 | 547 | 243 |
1994 | 560 | 240 |
1995 | 533 | 248 |
1996 | 542 | 269 |
1997 | 591 | 288 |
1998 | 604 | 310 |
1999 | 601 | 306 |
2000 | 619 | 327 |
2001 | 624 | 313 |
2002 | 624 | 315 |
2003 | 630 | 293 |
2004 | 582 | 267 |
2005 | 522 | 254 |
2006 | 459 | 224 |
2007 | 492 | 239 |
2008 | 427 | 225 |
2009 | 384 | 218 |
2010 | 334 | 234 |
2011 | 293 | 200 |
2012 | 284 | 166 |
2013 | 278 | 162 |
2014 | 269 | 167 |
2015 | 251 | 152 |
2016 | 253 | 152 |
2017 | 245 | 145 |
2018 | 220 | 129 |
2019 | 205 | 125 |
2020 | 168 | 102 |
2021 | 169 | 100 |
2022 | 154 | 94 |
2023 | 135 | 90 |
Download data file (Excel/CSV; 1.59 kB)
How this indicator was calculated
Note: Carbon monoxide, fine particulate matter, volatile organic compounds and ammonia are not shown in the chart due to their low share (≤ 1%) of total emissions in 2023. Excludes emissions from industries that generate electricity and heat as a supporting activity rather than as their primary purpose.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory.
The majority of the decline in SOX and NOX emissions between 1990 and 2023 occurred from 2005 onwards. Between 2005 and 2023, the share of electricity that came from burning fossil fuels fell from 25% to 18%. This decrease was mostly the result of a reduction in the use of coal power plants for electricity generation.Footnote 16 The emissions reductions since 2005 are mainly due to:
- the change in the mix of energy sources used to generate electricity
- the introduction of regulations targeting air pollutants and greenhouse gases emitted from electricity generation facilities
- domestic and international agreements
- better pollutant removal technologies used in smokestacks
- power plant closures
About the indicators
About the indicators
What the indicators measure
Air pollutant emissions indicators track emissions from human activities of 6 key air pollutants: sulphur oxides (SOX), nitrogen oxides (NOX), volatile organic compounds (VOCs), ammonia (NH3), carbon monoxide (CO) and fine particulate matter (PM2.5). Black carbon, which is a component of PM2.5, is also reported.Footnote 17 Sectoral indicators on air pollutant emissions from the oil and gas industry, transportation, off-road vehicles and mobile equipment and electric utilities provide additional analysis on the largest sources of Canada's air pollutant emissions.
For each air pollutant, the indicators are provided at the national and provincial/territorial levels. They also identify the major sources of emissions and provide links to detailed information on air pollutant emissions from facilities.Footnote 18
The graphs of emissions by province/territory, included in each pollutant’s section (except black carbon), refer to the year 2005 to allow comparison with the amended Gothenburg Protocol reference year (reductions from 2005 levels to be achieved by 2020 and maintained thereafter). The Gothenburg Protocol is an international treaty that commits countries to reduce their emissions of air pollutants. This ultimately improve Canadian air quality by reducing the transboundary flow of pollution Canada receives from other countries that are parties to the Protocol. The year 1990 (2013 for black carbon) is also included in these graphs as it marks the first year these substances were reported by the Air Pollutant Emissions Inventory (Black Carbon Emissions Inventory), while 2023 represents the most recent year for which data is available.
Why these indicators are important
Canadians are exposed to air pollutants on a daily basis, which can cause adverse health and environmental effects. Fine particulate matter (PM2.5) and ground-level ozone (O3) are key components of smog and have been associated with pulmonary and cardiovascular health issues even at very low levels. Nitrogen oxides, NOX (such as nitrogen dioxide [NO2]) and VOCs are the main contributors to the formation of O3. Nitrogen oxides, SOX (such as sulphur dioxide [SO2]), NH3 and VOCs also lead to the formation of PM2.5 in the air, in addition to the PM2.5 that is emitted directly. Sulphur oxides and NOX can also lead to the formation of acid deposition (e.g. acid rain) that can harm the environment, materials, living organisms, and humans.
The Canadian Environmental Protection Act (1999) contains more information on the federal regulations related to addressing air pollution. Additionally, Chapter 1 of Canada's Air Pollutant Emissions Inventory Report outlines relevant regulations.
Black carbon is an air pollutant as well as a powerful climate forcer. Black carbon is of particular significance in polar regions, where the deposition of particles on ice and snow darkens the surface, increasing the absorption of sunlight, and accelerating melting. Climate modelling shows that reducing emissions of black carbon is one of the most powerful actions available to countries to slow the pace of near-term warming in the Arctic,Footnote 19 a region that is already warming at a rate 3 times the global average.
The Air pollutant emissions indicators are intended to help track Canada’s progress in reducing air pollutant emissions from human-related sources and how effective these emission reduction measures are at improving ambient air quality in Canada.
Related initiatives
The indicators are relevant to the Sustainable Development Goals of the 2030 Agenda for Sustainable Development. They are linked to the 2030 Agenda's Goal 11: Sustainable Cities and Communities and Target 11.6: "By 2030, reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality and municipal and other waste management."
The indicators also help Canada report against its international compliance commitments under the Convention on Long-range Transboundary Air Pollution's amended Gothenburg Protocol. Under the amended protocol, Canada has committed to emission reductions by 2020 and beyond for 4 air pollutants:
- sulphur dioxide (SOX) (55% reduction from 2005 levels by 2020 and beyond)
- nitrogen oxides (NOX) (35% reduction from 2005 levels by 2020 and beyond)
- volatile organic compounds (VOCs) (20% reduction from 2005 levels by 2020 and beyond)
- fine particulate matter (PM2.5) (25% reduction from 2005 levels by 2020 and beyond)
Canada has been able to meet and maintain its emissions reduction commitments. In 2023, emissions were:
- 71% below 2005 levels for SOX
- 46% below 2005 levels for NOX
- 39% below 2005 levels for VOCs
- 41% below 2005 levels for PM2.5 (the commitment excludes open source emissions from road dust, construction operations, and crop production)
The indicators also demonstrate Canada’s contribution to the Arctic Council’s collective goal for black carbon emissions. Canada and other Arctic States agreed to collectively reduce emissions of black carbon by 25% to 33% of 2013 levels by 2025. Canada is on track to exceed its share of the goal, having reduced emissions by 40% below 2013 levels in 2023.
Related indicators
The Air health trends indicator provides an overview of the public health impacts attributable to outdoor air pollution in Canada.
The Air quality indicators track ambient concentrations of fine particulate matter (PM2.5), ozone (O3), sulphur dioxide (SO2), nitrogen dioxide (NO2), and volatile organic compounds (VOCs) at the national and regional levels and at local monitoring stations.
The Emissions of harmful substances to air indicators track human-related emissions to air of 3 toxic substances, namely mercury, lead and cadmium, and their compounds. For each substance, data are provided at the national, provincial/territorial and facility level and by source. Global emissions to air are also provided for mercury.
The Greenhouse gas emissions indicators report trends in total anthropogenic (human-made) GHG emissions at the national level, per person and per unit gross domestic product, by province and territory and by economic sector.
The Greenhouse gas emissions from large facilities indicator reports GHG emissions from the largest GHG emitters in Canada (industrial and other types of facilities).
The International comparison: air pollutant emissions in selected countries indicators compare Canada's emissions of 5 key air pollutants with those of top emitting member countries of the Organisation for Economic Co-operation and Development (OECD).
The Population exposure to outdoor air pollutants indicator tracks the proportion of the Canadian population living in areas where outdoor concentrations of air pollutants are less than or equal to the 2020 Canadian Ambient Air Quality Standards.
Data sources and methods
Data sources and methods
Data sources
The Air pollutant emissions indicators track emissions of 6 key air pollutants: sulphur oxides (SOX), nitrogen oxides (NOX), volatile organic compounds (VOCs), ammonia (NH3), carbon monoxide (CO) and fine particulate matter (PM2.5). The emissions data used are from Canada's Air Pollutant Emissions Inventory for the years 1990 to 2023.
Data for the black carbon indicator, a component of PM2.5, come from Canada's Black Carbon Emissions Inventory and are reported for the years 2013 to 2023 by source at the national level and by province and territory.
Facility data for local air pollutant emissions reported in interactive maps come from the National Pollutant Release Inventory and are available for the years 1993 to 2023.
More information
The Air Pollutant Emissions Inventory and the Black Carbon Emissions Inventory provide data and estimates on releases of air pollutants from human activities. These pollutants contribute to smog, acid rain, reduced air quality and climate change. Improvements to data and the methods for trend analysis are made periodically as new emission estimation methodologies are adopted and additional information is made available. Historical emissions are updated on the basis of these improvements.
Air Pollutant Emissions Inventory
The Air Pollutant Emissions Inventory fulfills many of Canada's international pollution levels reporting obligations. Specifically, under the 1979 Convention on Long-range Transboundary Air Pollution, Canada has committed to submitting an annual inventory of emissions of key air pollutants to the United Nations Economic Commission for Europe. The inventory is a comprehensive assessment of 17 air pollutants,Footnote 20 combining emissions reported by facilities to the National Pollutant Release Inventory with emissions of all other sources estimated by Environment and Climate Change Canada. Estimates are developed using the latest estimation methods and are based on published statistics or other sources of information such as surveys and reports. The Air Pollutant Emission Inventory provides a comprehensive overview of pollutant emissions across Canada.
The national and provincial/territorial inventory data are current as of March 14, 2025, and cover the period from 1990 to 2023. Emissions data are compiled into a database for reporting approximately one year after data collection, validation and calculation have been completed. After this process is the interpretation of results and public reporting of the inventory. The Air pollutant emissions indicators are reported following the public release of the inventory data.
Black carbon emissions inventory
As a member of the Arctic Council, Canada committed under the Framework for Action on Enhanced Black Carbon and Methane Emissions Reductions (2015) to submit periodic inventories of its black carbon emissions to the Arctic Council Secretariat. Canada already voluntarily reports black carbon emissions to the United Nations Economic Commission for Europe as a Party to the Gothenburg Protocol, which was amended in 2012 to add fine particulate matter. The Black Carbon Emissions Inventory is compiled using PM2.5 emissions data from combustion-related sources from the Air Pollutant Emissions Inventory. Black carbon estimates are published separately from the Air Pollutant Emissions Inventory. The data are current as of March 14, 2025.
Black carbon is a short-lived climate pollutant, (SLCP), meaning it contributes to warming but has a relatively short lifespan in the atmosphere (from a few days to a few weeks) compared to carbon dioxide (CO2) (which can persist in the atmosphere for hundreds to thousands of years) and other longer-lived greenhouse gases (GHGs). Although their life spans are short, SLCPs are potent contributors to warming of the Earth's surface.Footnote 21 When black carbon deposits on snow and ice, it darkens the surface, accelerating heating and melting, creating a warming impact that is particularly strong in the Arctic and other snow covered areas (including glaciers).Footnote 22 Reducing emissions of SLCPs, including black carbon, help slow near-term warming – the impacts of reductions are seen quickly because SLCPs have such short lifespans in the atmosphere. The Intergovernmental Panel on Climate Change (IPCC) special report on Global Warming states that reductions in short-lived climate pollutants are required to limit warming to a maximum of 1.5oC, and Canada's Changing Climate Report flags short-lived climate pollutants as an important part of climate policy discussions because mitigation can slow global temperature warming and improve air quality.
National Pollutant Release Inventory
The National Pollutant Release Inventory is a database of pollutant releases (to air, water and land), disposals and transfers for recycling from industrial, commercial and institutional facilities. The data from these facilities is provided by the operators of the facilities as mandated by the Canadian Environmental Protection Act (the Act). Under the Act, owners or operators of facilities that manufacture, process or otherwise use or release one or more of the substances tracked by the inventory, and meet substance-specific reporting thresholds and other requirements, must report their pollutant releases, disposals and transfers annually to the department. The inventory data from 1993 to 2023 are current as of November 27, 2025.
Methods
Emissions data from Canada's national inventories are used to produce the indicators for the 6 key air pollutants. Data are grouped to report on the sources that contribute the majority of emissions for each pollutant. Canada's national inventories use the latest advancements in scientific knowledge to estimate or measure emissions for the various air pollutant sources.
More information
Compilation of air pollutant emissions
The Air Pollutant Emissions Inventory is developed using 2 types of information:
- facility-reported data, consisting of emissions from relatively large industrial, commercial and institutional facilities
- in-house estimates, including diffuse sources and other sources that are too numerous to be accounted for individually, such as road and non-road vehicles, agricultural activities, construction and solvent use
The Air Pollutant Emissions Inventory is developed using many sources of information, procedures and emission estimation models. Emissions data reported by individual facilities to the department's National Pollutant Release Inventory are supplemented with documented, science-based estimation tools to quantify total emissions. Together, these data sources provide a comprehensive overview of pollutant emissions across Canada.
A compilation framework has been developed that makes use of the best available data, while ensuring that there is no double-counting or omissions. Additional information on the inventory compilation process is provided in Chapter 3 of the Air Pollutant Emissions Inventory Report.
Facility-reported emissions data
Facility-reported emissions data generally refers to any stationary sources that emit pollutants through stacks or other equipment at specific locations. The major source of facility-reported data is the National Pollutant Release Inventory.
Facility-reported data from the National Pollutant Release Inventory are used in the Air Pollutant Emissions Inventory without modifications, except when data quality issues are detected and not addressed during the quality control exercise. The National Pollutant Release Inventory reporting requirements and thresholds vary by pollutant and, in some cases, by industry. Details on these reporting requirements and thresholds are available on the National Pollutant Release Inventory website.
A distinction has been made between reporting facilities and non-reporting facilities. Reporting facilities meet the threshold required to report to the National Pollutant Release Inventory; while non-reporting facilities do not meet these thresholds due to their size or emission levels, and therefore are not required to report to the inventory. Some facilities may be required to report emissions on only certain pollutants. Therefore, emissions from the non-reporting facilities or of non-reported pollutants must be estimated in‑house to ensure complete coverage.
In-house emission estimates
In-house emission estimates are calculated with information such as production data and activity data, using various estimation methodologies and emission models. These emission estimates are at the national, provincial and territorial levels, rather than at any specific geographic locations. These include emissions from non-industrial, residential, commercial, transportation, and other sources, such as open burning, agricultural activities and construction operations. The Air Pollutant Emissions Inventory uses in-house estimates for the following emission sources:
- any residential, governmental, institutional, or commercial operation that does not report to the National Pollutant Release Inventory
- on-site solid waste disposal facilities
- motor vehicles, aircraft, vessels or other transportation equipment or devices
- other sources, such as open burning, agricultural activities and construction operations
In general, in-house emission estimates are calculated from activity data and emission factors.Footnote 23 Activity data usually comprise statistical production or process data at the provincial, territorial or national level. This information is typically provided by provincial/territorial agencies, federal government departments, industry associations, etc. For each source category, activity data are combined with emission factors to produce provincial/territorial-level emission estimates.
The in-house emission estimate methodologies and emission models used in Canada are often based on those developed by the United States Environmental Protection Agency (U.S. EPA) and are adapted to reflect the Canadian climate, fuels, technologies and practices. Methods used in Canada's Air Pollutant Emissions Inventory are therefore generally consistent with those used in the United States or those recommended in the emission inventory guidebook.Footnote 24
The Air Pollutant Emissions Inventory reports air pollutant emissions from mobile sources such as on-road vehicles, off-road vehicles and engines. For the current edition of the Air Pollutant Emissions Inventory, an emissions estimation model developed by the U.S. EPA (MOVES) was used. The emissions for off-road vehicles and engines (such as graders, heavy trucks, outboard motors and lawnmowers) were estimated using the U.S. EPA's NONROAD emission estimation model (see "off-road vehicles and equipment" in Table A2-1 of Annex 2 of the Air Pollutant Emissions Inventory Report). The parameters in both models were modified to take into account variations in the Canadian vehicle fleet, emission control technologies, types of fuels, vehicle standards, and types of equipment engines and their application in various industries. The emission estimates for civil and international aviation, railways and navigation are estimated using detailed vehicle movement statistics coupled with fuel consumption, engine information, and emission rates by vehicle types.
Calculation of black carbon emissions
Emissions of black carbon are calculated by applying factors to estimate the fraction of black carbon in PM2.5 emissions from combustion-related sources, with some exceptions, for example, the mobile sources, where models are used. The factors primarily come from the United States Environmental Protection Agency's SPECIATE database. SPECIATE is a repository of particulate matter speciation profilesFootnote 25 of air pollution sources. The ratios used for each source are available on the Government of Canada’s Open Data Portal. More information on black carbon emission estimation methods can be found in Chapter 3 of Canada’s Black Carbon Inventory Report.
Recalculations
Emission recalculation is an essential practice in the maintenance of an up-to-date air pollutant emissions inventory. The Air Pollutant Emissions Inventory is continuously updated with improved estimation methodologies, statistics and more recent and appropriate emission factors. As new information and data become available, previous estimates are updated and recalculated to ensure a consistent and comparable trend in emissions. Recalculations of previously reported emission estimates are common for both in-house estimates and facility-reported emission data. More information on recalculations is provided in Annex 3 of the Air Pollutant Emissions Inventory Report.
Emissions reconciliation
In several sectors, estimation of total emissions involves combining estimates provided by facilities with estimates developed in-house by the department. To prevent double counting of emissions and to confirm that the Air Pollutant Emissions Inventory includes all emissions, a comparison and reconciliation of emission estimates from various sources is performed for each pollutant, industry sector and geographical region, as appropriate. More information on the reconciliation process is provided in section 3.4 of the Air Pollutant Emissions Inventory Report.
Temporal coverage
Historical data are provided at the national level for the period from 1990 to 2023, except for black carbon, which covers the period from 2013 to 2023. For the regional indicators (provincial/territorial), emissions are presented for 1990 (2013 for black carbon) and 2023. Facility level emissions information are available from 2011 to 2023.
Air pollutant emissions by source classification
For the purpose of reporting the indicators, calculated emissions data from the Air Pollutant Emissions Inventory and Black Carbon Emissions Inventory are grouped into the following 13 sources:
- agriculture (livestock, crop production and fertilizer)
- building heating and energy generation
- dust and fires
- electric utilities
- home firewood burning
- incineration and waste
- manufacturing
- miscellaneous
- off-road vehicles and mobile equipment
- oil and gas industry
- ore and mineral industries
- paints and solvents
- transportation (road, rail, air and marine)
Table 1 shows the allocation of air pollutant emission sources reported in the indicators compared with the sources and sectors reported by the Air Pollutant Emissions Inventory.
Sources in the indicators | Sources and sectors in the Air Pollutant Emissions Inventory and Black Carbon Emissions Inventory |
---|---|
Agriculture (livestock, crop production and fertilizer) | Agriculture: Animal production |
Agriculture (livestock, crop production and fertilizer) | Agriculture: Crop production |
Agriculture (livestock, crop production and fertilizer) | Agriculture: fuel use |
Building heating and energy generation | Commercial/Residential/Institutional: Commercial and institutional fuel combustion |
Building heating and energy generation | Commercial/Residential/Institutional: Residential fuel combustion |
Dust and fires | Dust: Coal transportation |
Dust and fires | Dust: Construction operations |
Dust and fires | Dust: Mine tailings |
Dust and fires | Dust: Paved roads |
Dust and fires | Dust: Unpaved roads |
Dust and fires | Fires: Prescribed burning |
Dust and fires | Fires: Structural fires |
Electric utilities | Electric power generation (utilities): Coal |
Electric utilities | Electric power generation (utilities): Diesel |
Electric utilities | Electric power generation (utilities): Natural gas |
Electric utilities | Electric power generation (utilities): Landfill gas [A] |
Electric utilities | Electric power generation (utilities): Other (electric power generation) |
Home firewood burning | Commercial/Residential/Institutional: Home firewood burning |
Incineration and waste | Incineration and waste: Crematoriums |
Incineration and waste | Incineration and waste: Waste incineration |
Incineration and waste | Incineration and waste: Waste treatment and disposal |
Manufacturing | Manufacturing: Abrasives manufacturing |
Manufacturing | Manufacturing: Bakeries |
Manufacturing | Manufacturing: Biofuel production |
Manufacturing | Manufacturing: Chemicals industry |
Manufacturing | Manufacturing: Construction fuel combustion |
Manufacturing | Manufacturing: Food preparation |
Manufacturing | Manufacturing: Glass manufacturing |
Manufacturing | Manufacturing: Grain industry |
Manufacturing | Manufacturing: Metal fabrication |
Manufacturing | Manufacturing: Plastics manufacturing |
Manufacturing | Manufacturing: Pulp and paper industry |
Manufacturing | Manufacturing: Textiles |
Manufacturing | Manufacturing: Vehicle manufacturing (engines, parts, assembly, painting) |
Manufacturing | Manufacturing: Wood products |
Manufacturing | Manufacturing: Other (manufacturing) |
Miscellaneous | Commercial/Residential/Institutional: Commercial cooking |
Miscellaneous | Commercial/Residential/Institutional: Human [B] |
Miscellaneous | Commercial/Residential/Institutional: Marine cargo handling |
Miscellaneous | Commercial/Residential/Institutional: Other (miscellaneous) |
Miscellaneous | Commercial/Residential/Institutional: Service stations |
Off-road vehicles and mobile equipment | Transportation and mobile equipment: Off-road diesel vehicles and equipment |
Off-road vehicles and mobile equipment | Transportation and mobile equipment: Off-road gasoline / liquefied petroleum gas / natural gas vehicles and equipment |
Oil and gas industry | Oil and gas industry: Downstream oil and gas industry |
Oil and gas industry | Oil and gas industry: Upstream oil and gas industry |
Ore and mineral industries | Ore and mineral industries: Aluminum industry |
Ore and mineral industries | Ore and mineral industries: Asphalt paving industry |
Ore and mineral industries | Ore and mineral industries: Cement and concrete industry |
Ore and mineral industries | Ore and mineral industries: Foundries |
Ore and mineral industries | Ore and mineral industries: Iron and steel industry |
Ore and mineral industries | Ore and mineral industries: Iron ore pelletizing |
Ore and mineral industries | Ore and mineral industries: Mineral products industry |
Ore and mineral industries | Ore and mineral industries: Mining and rock quarrying |
Ore and mineral industries | Ore and mineral industries: Non-ferrous refining and smelting industry |
Paints and solvents | Paints and solvents: Dry cleaning |
Paints and solvents | Paints and solvents: General solvent use |
Paints and solvents | Paints and solvents: Printing |
Paints and solvents | Paints and solvents: Surface coatings |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Air transportation |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Heavy-duty diesel vehicles |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Heavy-duty gasoline vehicles |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Heavy-duty liquefied petroleum gas / natural gas vehicles |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Light-duty diesel trucks |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Light-duty diesel vehicles |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Light-duty gasoline trucks |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Light-duty gasoline vehicles |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Light-duty liquefied petroleum gas / natural gas trucks |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Light-duty liquefied petroleum gas / natural gas vehicles |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Domestic marine navigation, fishing and military |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Motorcycles |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Rail transportation |
Transportation (road, rail, air and marine) | Transportation and mobile equipment: Tire wear and brake lining |
Note: [A] Includes electric power generation from combustion of waste materials by utilities and by industry for commercial sale and/or private use. [B] Includes human respiration, perspiration and dental amalgams.
For display purposes, smaller emitting sources are sometimes grouped together under the title Other sources in the charts of air pollutant emissions by source. The names of the sources grouped as such are listed in the notes of each chart.
Sectoral indicators
Sectoral indicators on air pollutant emissions from transportation, off-road vehicles and mobile equipment, electric utilities and the oil and gas industry provide additional analysis on the largest sources of Canada's air pollutant emissions. These indicators also rely on calculated emissions data from the Air Pollutant Emissions Inventory.
These indicators are provided at the national level. They identify the contribution of each sector to the national emissions of air pollutants for the year 2023. They also provide information about emissions of selected pollutants, by sector, for the period from 1990 to 2023.
Tables 2 through 4 below show the alignment of air pollutant emission sources reported in the Air pollutant emissions indicators compared with those reported by the sectoral indicators.
Air pollutant emissions from transportation, off-road vehicles and mobile equipment | Sources and sectors in the Air Pollutant Emissions Inventory and Black Carbon Emissions Inventory |
---|---|
Air, marine and rail travel | Transportation and mobile equipment: Air transportation |
Air, marine and rail travel | Transportation and mobile equipment: Domestic marine navigation, fishing and military |
Air, marine and rail travel | Transportation and mobile equipment: Rail transportation |
Large trucks and buses | Transportation and mobile equipment: Heavy-duty diesel vehicles |
Large trucks and buses | Transportation and mobile equipment: Heavy-duty gasoline vehicles |
Large trucks and buses | Transportation and mobile equipment: Heavy-duty liquefied petroleum gas / natural gas vehicles |
Off-road vehicles and equipment, tire wear and brake lining | Transportation and mobile equipment: Off-road diesel vehicles and equipment |
Off-road vehicles and equipment, tire wear and brake lining | Transportation and mobile equipment: Off-road gasoline / liquefied petroleum gas / natural gas vehicles and equipment |
Off-road vehicles and equipment, tire wear and brake lining | Transportation and mobile equipment: Tire wear and brake lining |
Passenger cars and motorcycles | Transportation and mobile equipment: Light-duty diesel vehicles |
Passenger cars and motorcycles | Transportation and mobile equipment: Light-duty gasoline vehicles |
Passenger cars and motorcycles | Transportation and mobile equipment: Light-duty liquefied petroleum gas / natural gas vehicles |
Passenger cars and motorcycles | Transportation and mobile equipment: Motorcycles |
Passenger light trucks | Transportation and mobile equipment: Light-duty diesel trucks |
Passenger light trucks | Transportation and mobile equipment: Light-duty gasoline trucks |
Passenger light trucks | Transportation and mobile equipment: Light-duty liquefied petroleum gas / natural gas trucks |
Air pollutant emissions from electric utilities | Sources and sectors in the Air Pollutant Emissions Inventory and Black Carbon Emissions Inventory |
---|---|
Coal | Electric power generation (utilities): Coal |
Diesel | Electric power generation (utilities): Diesel |
Natural gas | Electric power generation (utilities): Natural gas |
Other | Electric power generation (utilities): Waste materials [A] |
Other | Electric power generation (utilities): Other (electric power generation) |
Note: [A] Includes electric power generation from combustion of waste materials by utilities and by industry for commercial sale and/or private use.
Air pollutant emissions from the oil and gas industry | Sources and sectors in the Air Pollutant Emissions Inventory and Black Carbon Emissions Inventory |
---|---|
Downstream oil and gas | Oil and gas industry: Downstream oil and gas industry |
Upstream oil and gas | Oil and gas industry: Upstream oil and gas industry |
Recent changes
The emission estimates reported in Canada's Air Pollutant Emissions Inventory and Canada’s Black Carbon Emissions Inventory used in the indicators undergo continuous improvements, leading to recalculations. Annex 3 of the Air Pollutant Emissions Inventory Report and section 3.2 of Canada's Black Carbon Emissions Inventory Report contain more information about the recent changes made.
Caveats and limitations
The methodologies for compiling air pollutant emissions generally improve over time, and revisions are made to the Air Pollution Emissions Inventory. As a result of this, the emissions and trends reported for the indicators may be different from those previously published.
Some area source emissions were not updated for 2023 due to the unavailability of activity-level statistics at the time of compilation. In these cases, the emission estimates from the most recent year available were used.
The Air Pollutant Emissions Inventory (APEI) uses facility information from the National Pollutant Release Inventory and other sources. The version of the data published by the National Pollutant Release Inventory may not be identical to that used in the Air Pollutant Emissions Inventory at a given time because of updates to point source data from National Pollutant Release Inventory reporting. The inventory also uses different rounding protocols in its final report and total emissions reported in the indicators may be slightly different.
The Black Carbon Emissions Inventory generally uses the same sources as the APEI, however, work will continue to improve the completeness and accuracy of the inventory, quantifying the emissions that are not yet captured.
Resources
Resources
References
Environment and Climate Change Canada (2015) Climate and Clean Air Coalition. Retrieved on March 18, 2025.
Environment and Climate Change Canada (2017) Using and interpreting data from the National Pollutant Release Inventory. Retrieved on March 18, 2025.
Environment and Climate Change Canada (2025) National Pollutant Release Inventory. Retrieved on March 18, 2025.
Environment and Climate Change Canada (2024) National Pollutant Release Inventory: tools and resources. Retrieved on March 18, 2025.
Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory Report. Retrieved on March 18, 2025.
Environment and Climate Change Canada (2025) Canada's Black Carbon Inventory Report. Retrieved on March 18, 2025.
Related information
Interactive figures
Updated June 2025
These interactive figures support the Air pollutant emissions indicators. Use them to explore the latest emissions data for the 6 key air pollutants and black carbon in a dynamic and customizable format.
Select data by using the drop-down menu above each figure and clear your selections by clicking the "Reset figures" button on the right-hand side of the dashboard. All values in the figures will automatically update based on your selections.
You can also choose to use your keyboard to navigate the figures.
Source: Environment and Climate Change Canada (2025) Air Pollutant Emissions Inventory, Canada's Black Carbon Emissions Inventory.
Download data file for key air pollutants (Excel/CSV; 11 MB)
Download data file for black carbon (Excel/CSV; 110 kB)
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