Emissions of harmful substances to air

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Emissions of some substances can harm human health, wildlife and biological diversity. For example, small particles of toxic metals can travel long distances in the air, be inhaled, or settle on the ground and in water. There, they can enter the food web and build up in the tissues of living organisms. Exposure to these substances, even in small amounts, can be hazardous to both humans and wildlife. Mercury and its compounds, lead, and inorganic cadmium compounds are listed as toxicFootnote 1  substances under the Canadian Environmental Protection Act, 1999. The emissions of harmful substances to air indicator reports on mercury, lead and cadmium emissions from human-related activities.

Summary

Key results

  • In 2021, mercury, lead and cadmium emissions had decreased by 90%, 91% and 94%, respectively from 1990 levels

Percentage change of mercury, lead and cadmium emissions from 1990 level, Canada

Mercury, lead and cadmium emissions to air, Canada, 1990 to 2020 (see the data table below for the long description)
Data table for the long description
Percentage change of mercury, lead and cadmium emissions from 1990 level, Canada
Year Mercury
(percentage change from 1990 level)
Lead
(percentage change from 1990 level)
Cadmium
(percentage change from 1990 level)
1990 0 0 0
1991 0 -4 -13
1992 1 1 -11
1993 -43 -35 -81
1994 -48 19 -6
1995 -59 -25 -74
1996 -56 -18 -66
1997 -63 -30 -45
1998 -67 -38 -44
1999 -69 -47 -51
2000 -70 -47 -54
2001 -72 -47 -16
2002 -74 -56 -51
2003 -75 -63 -61
2004 -74 -70 -59
2005 -76 -77 -57
2006 -79 -73 -50
2007 -77 -74 -65
2008 -79 -76 -72
2009 -83 -78 -74
2010 -84 -81 -80
2011 -88 -86 -90
2012 -88 -87 -88
2013 -88 -89 -90
2014 -89 -88 -91
2015 -89 -86 -91
2016 -90 -86 -91
2017 -90 -84 -92
2018 -90 -86 -92
2019 -90 -88 -92
2020 -91 -89 -95
2021 -90 -91 -94

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How this indicator was calculated

Note: The indicator reports emissions from human-related activities only. It does not include emissions from natural sources such as forest fires or volcanoes.
Source: Environment and Climate Change Canada (2023) Air Pollutant Emissions Inventory.

The decrease in mercury, lead and cadmium emissions are mostly attributed to a large drop in emissions from the non-ferrous refining and smelting industry. This decline was primarily due to the implementation of pollution prevention plans, the closing of outdated smelters, compliance with federal and provincial legislation, and conformance with guidelines introduced over this period. The changes in facility processes and adoption of emission reduction technologies also contributed to the reduction of mercury emissions.

Emissions of mercury have not changed substantially since 2011. This may be due to a range of competing factors such as increases in production levels as well as the ongoing implementation of new cleaner technologies, facility closures and regulations coming into force in the earlier years.

Cadmium emissions fluctuated between 1990 and 2006, but decreased steadily from 2007 onward. Fluctuations in cadmium emissions prior to 2010 are mostly driven by emissions from a non-ferrous refining and smelting facility in Manitoba.

While overall lead emissions declined between 1990 and 2021, they did increase slightly from 2014 to 2017 and continued to decline afterwards. These reductions are partly due to the closure of some non-ferrous metal smelting and refining facilities, the installation of more efficient emission control equipment, changes in lead concentrations in smelter feed and changes in production levels at some facilities. 

Mercury

Emissions of mercury to air

Mercury is a naturally occurring metal that can be emitted to the air by natural processes (like melting permafrost, volcanic activity and soil and rock erosion), human activities (such as coal-fired electricity generation and waste incineration and treatment), and the improper disposal of mercury-containing products (such as batteries, thermometers, and fluorescent lamps).

Mercury emissions are both a local and a global concern. Mercury can travel long distances in the atmosphere and may settle anywhere in Canada, including sensitive areas such as the Canadian Arctic and the Great Lakes. Once deposited, mercury in the environment can be re-emitted into the atmosphere. Re-emission is a more significant source of atmospheric mercury pollution than anthropogenic emissions from Canadian sources.Footnote 2 

Mercury can also have significant negative impacts on human health and the environment as mercury persists in the environment and accumulates in food chains over time. In humans, exposure poses a risk to populations who rely heavily on the consumption of aquatic and marine species, such as northern and Indigenous communities, whose traditional diet includes predatory fish (for example, freshwater trout and Arctic char) and marine mammals.

Mercury emissions to air by source
Mercury emissions to air by province and territory
Mercury emissions to air from facilities
Global mercury emissions to air

Mercury emissions to air by source

Key results

  • In 2021, 3.2 tonnes of mercury were emitted in Canada
  • The ore and mineral industries was the highest emitting sector, representing emissions from the non-ferrous refining and smelting industry, the cement and concrete industry, the iron and steel industry, and other ore and mineral industries. This sector emitted 38% (or 1.2 tonnes) of the annual total
  • Between 1990 and 2021, mercury emissions decreased by 91% (or 30.4 tonnes)
  • Following a 43% decrease between 1992 and 1993, emissions have generally declined

Mercury emissions to air by source, Canada, 1990 to 2021

Mercury emissions to air by source, Canada, 1990 to 2020 (see the data table below for the long description)
Data table for the long description
Mercury emissions to air by source, Canada, 1990 to 2021
Year Electric utilities
(emissions in tonnes)
Iron and steel industry
(emissions in tonnes)
Incineration and waste
(emissions in tonnes)
Cement and concrete industry
(emissions in tonnes)
Non-ferrous refining and smelting industry
(emissions in tonnes)
Other sources
(emissions in tonnes)
Total
(emissions in tonnes)
1990 2.25 0.71 2.58 0.46 24.89 2.75 33.64
1991 2.12 0.73 2.77 0.38 24.86 2.79 33.64
1992 2.35 0.74 3.00 0.36 24.77 2.76 33.98
1993 2.14 0.75 3.18 0.37 10.11 2.69 19.24
1994 2.06 0.74 3.20 0.41 8.25 2.71 17.36
1995 1.99 0.75 3.16 0.41 4.64 2.69 13.65
1996 2.09 0.76 3.21 0.44 5.67 2.60 14.78
1997 2.24 0.81 3.16 0.45 3.38 2.46 12.50
1998 2.37 0.83 2.15 0.45 2.83 2.34 10.96
1999 2.37 0.84 2.11 0.47 2.27 2.28 10.33
2000 2.05 0.80 2.20 0.39 1.94 2.59 9.95
2001 2.09 0.79 2.10 0.37 2.12 1.85 9.32
2002 2.06 0.85 1.93 0.37 1.75 1.87 8.84
2003 2.37 0.91 1.69 0.35 1.29 1.91 8.52
2004 2.31 0.86 1.54 0.22 1.90 1.78 8.61
2005 2.17 0.86 1.41 0.21 1.70 1.59 7.94
2006 2.00 0.78 1.33 0.30 1.25 1.52 7.18
2007 2.17 0.73 1.66 0.32 1.41 1.52 7.82
2008 1.63 0.72 1.84 0.30 1.01 1.57 7.07
2009 1.67 0.60 0.90 0.29 0.84 1.42 5.73
2010 1.58 0.67 0.82 0.31 0.55 1.40 5.33
2011 1.02 0.62 0.83 0.30 0.22 1.13 4.12
2012 0.86 0.66 0.71 0.30 0.26 1.09 3.87
2013 0.85 0.69 0.66 0.31 0.36 1.06 3.93
2014 0.71 0.68 0.74 0.30 0.29 0.97 3.69
2015 0.73 0.64 0.72 0.38 0.18 0.91 3.57
2016 0.67 0.68 0.73 0.34 0.22 0.88 3.53
2017 0.63 0.61 0.73 0.33 0.14 0.85 3.30
2018 0.61 0.60 0.73 0.30 0.20 0.96 3.40
2019 0.60 0.52 0.74 0.30 0.12 0.91 3.20
2020 0.50 0.49 0.80 0.24 0.16 0.86 3.05
2021 0.50 0.48 0.85 0.30 0.19 0.88 3.20

Note: Totals may not add up due to rounding. 

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How this indicator was calculated

Note: The indicator reports emissions from human-related activities only. It does not include emissions from natural sources such as forest fires or volcanoes. The category "other sources" includes agriculture (livestock, crop production and fertilizer), building heating and energy generation, home firewood burning, manufacturing, the oil and gas industry, other ore and mineral industries (the aluminum industry, the asphalt paving industry, foundries, iron pelletizing and mining and rock quarrying), transportation (road, rail, air and marine) and other miscellaneous sources. For more details on the sources, consult the Data sources and methods
Source: Environment and Climate Change Canada (2023) Air Pollutant Emissions Inventory.

The largest reduction in mercury emissions between 1990 and 2021 was from the non-ferrous refining and smelting industry. This industry reduced its emissions by 99% (from 24.9 tonnes in 1990 to 0.2 tonnes in 2021), contributing to 81% of the overall mercury emissions reduction. The reductions were due primarily to changes in facility processes and adoption of emission reduction technologies, the closing of outdated smelters, compliance with federal and provincial legislation and conformance with guidelines. For example, the actions of a single large facility in Manitoba lowered the province's emissions by 99% from 1990 to 2010. These actions included changing its zinc production method, improving its controls of particulate matter emissions, switching to cleaner fuels, and ceasing operation of an outdated copper smelter.

Between 1990 and 2021, emissions from electric utilities, and incineration and waste declined by 78% and 67% (1.7 tonnes each) respectively. The decrease from electric utilities was largely due to the closure of coal-fired power plants.Footnote 3  Combined, these sources contributed a further 11% to the total decrease in mercury emissions.

Mercury emissions to air by province and territory

Key results

  • In 2021, Ontario, Saskatchewan and Quebec accounted for 70% of national mercury emissions
  • Between 1994 and 2021, Manitoba had the largest reduction in emissions with a decrease of 4.3 tonnes

Mercury emissions to air by province and territory, Canada, 1994, 2011 and 2021

Mercury emissions to air by province and territory, Canada, 1994, 2010 and 2020 (see the data table below for the long description)
Data table for the long description
Mercury emissions to air by province and territory, Canada, 1994, 2011 and 2021
Province or territory 1994
(emissions in tonnes)
2011
(emissions in tonnes)
2021
(emissions in tonnes)
Newfoundland and Labrador 0.28 0.09 0.04
Prince Edward Island 0.02 0.02 0.02
Nova Scotia 0.34 0.13 0.08
New Brunswick 0.44 0.16 0.04
Quebec 2.90 0.70 0.66
Ontario 3.40 1.08 1.04
Manitoba 4.34 0.08 0.06
Saskatchewan 0.62 0.75 0.54
Alberta 1.57 0.66 0.38
British Columbia 3.35 0.44 0.34
Yukon < 0.01 < 0.01 < 0.01
Northwest Territories 0.10[A] < 0.01 < 0.01
Nunavut n/a 0.01 0.01
Canada 17.36 4.12 3.20

Note: n/a = not applicable. [A] Value for 1994 includes emissions from Nunavut, which was officially separated from the Northwest Territories in 1999. Totals may not add up due to rounding. 

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How this indicator was calculated

Note: Emissions from the Northwest Territories for 1994 includes emissions from Nunavut, which was officially separated from the Northwest Territories in 1999. The indicator reports emissions from human-related activities only. It does not include emissions from natural sources such as forest fires or volcanoes. Some reported emissions from Newfoundland and Labrador, Prince Edward Island, New Brunswick, Yukon, the Northwest Territories and Nunavut are too small to see in the figure. To access all available years data please refer to the indicator’s interactive figures or, for the full dataset, to the Air Pollutant Emissions Inventory.
Source: Environment and Climate Change Canada (2023) Air Pollutant Emissions Inventory.

In 2021, Ontario had the highest mercury emissions, accounting for 32% (1.0 tonnes) of the national total. These emissions came mostly from the incineration and waste, the iron and steel and the cement and concrete industry, which together accounted for 65% of the total provincial emissions.

For the most recent year, the largest source within each province and territory was:

  • the incineration and waste industry in Alberta, Manitoba, Ontario, Quebec, New Brunswick, Prince Edward Island, Yukon and Nunavut
  • electric utilities (mostly coal power plants) in Saskatchewan and Nova Scotia
  • the cement and concrete industry in British Columbia
  • the iron ore industry in Newfoundland and Labrador
  • the mining and rock quarrying industry in the Northwest Territories

All provinces and territories had lower emissions in 2021 compared to 1994, with the exception of Nunavut, which separated from the Northwest Territories in 1999 and thus did not have data available for comparison for 1994. Manitoba had the largest decline in emissions between 1994 and 2021. This decline was mostly due to changes in zinc processing technology and production levels, and the closure of an outdated copper smelter at a non-ferrous refining and smelting facility.

Unlike the other provinces and territories, whose emissions have declined or remained stable since 1994, Ontario, Saskatchewan, and Quebec reported increasing emissions from 1994 until 1998, 2005, and 1996 respectively. Since those years, their emissions have declined or remained stable.

Alberta had the largest decrease in emissions between 2011 and 2021 (0.3 tonnes). This decline was largely from electric utilities, likely due to the closure of coal-fired power plants.Footnote 3

Mercury emissions to air from facilities

The National Pollutant Release Inventory provides detailed information on emissions from industrial, commercial and institutional facilities that meet its reporting criteria.

The Canadian Environmental Sustainability Indicators provide access to this information through an online interactive map. The map allows you to explore mercury emissions to air from individual facilities.

In 2021, facility-reported mercury emissions represent 60% of total national mercury emissions.Footnote 4   Of these facilities:

  • 60 facilities reported emissions under 0.5 kilogram (kg)
  • 109 facilities reported emissions between 0.5 to 100 kg
  • 3 facilities reported emissions over 100 kg, which were located in Quebec (1) and Saskatchewan (2) 

Mercury emissions to air by facility, Canada, 2021

Mercury emissions to air by facility, 2020 (see the long description below)
Long description

The map of Canada shows the amount of mercury in kilograms emitted to air in 2021 by facility. Facilities are categorized by the amount of mercury emitted. The categories are: less than 0.5 kilograms, 0.5 to less than 5 kilograms, 5 to less than 25 kilograms, 25 to less than 50 kilograms, 50 to less than 100 kilograms and 100 to 192 kilograms.

Data for the map

Navigate data using the interactive map

How this indicator was calculated

Source: Environment and Climate Change Canada (2023) National Pollutant Release Inventory.

Global mercury emissions to air

Key results

  • In 2015, the latest year for which data are available, global mercury emissionsFootnote 5  to air from human activity were estimated to be 2 220 tonnes
  • The East and Southeast Asia, South America and Sub-Saharan Africa regions accounted for 73% of the global total
  • The North America region (includes only Canada and the United States) emitted 40 tonnes, or about 2% of the global total
  • Canada emitted less than 5 tonnes or about 0.2% of the global total

Global mercury emissions to air, 2015

Global mercury emissions to air, 2015 (see the data table below for the long description)
Data table for the long description
Global mercury emissions to air, 2015
Region Mercury emissions
(tonnes)
Percentage of global emissions
East and Southeast Asia 859 38.6
South America 409 18.4
Sub-Saharan Africa 360 16.2
South Asia 225 10.1
Commonwealth of Independent States (CIS) and other European countries 124 5.6
European Union (EU28) 77 3.5
Middle Eastern States 53 2.4
Central America and the Caribbean 46 2.1
North America 40 1.8
North Africa 21 0.9
Australia, New Zealand and Oceania 9 0.4

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How this indicator was calculated

Note: CIS = Commonwealth of Independent States. The CIS includes Armenia, Azerbaijan, Belarus, Georgia, Kazakhstan, Kyrgyzstan, Moldova, Russian Federation, Tajikistan, Turkmenistan, Ukraine and Uzbekistan. The 28 member countries of the European Union includes Austria, Belgium, Bulgaria, Croatia, Republic of Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden and the United Kingdom. The North America region includes only Canada and the United States, Mexico is grouped into the Central America and the Caribbean region.
Source: United Nations Environmental Program (2019) Global Mercury Assessment 2018.

Mercury in the air can travel hundreds to thousands of kilometres via air masses before being deposited.Footnote 6  For example, Environment and Climate Change CanadaFootnote 2  estimates that over 95% of the human-related mercury deposited in Canada came from sources outside of the country.

Lead

Emissions of lead to air

Lead is a naturally occurring metal found in the Earth's crust and can be released during natural processes, such as rock and soil erosion. Although these natural releases of lead occur, most lead emissions come from industrial activities, such as metal refining and smelting, and various combustion processes. It is also used in the manufacture of vehicle lead-acid batteries worldwide, as well as pipes, sheeting, and within glass to prevent radiation exposure from television and computer screens.

Lead emissions to air can be deposited on land or water surfaces and accumulate in soils, sediments, humans and wildlife. Exposure to lead, even in small amounts, can be hazardous to both humans and wildlife. In humans, chronic exposure to relatively low levels may affect the central and peripheral nervous systems, blood pressure, and renal function, and may result in reproductive problems and developmental neurotoxicity.

Emissions of lead to air by source
Emissions of lead to air by province and territory
Emissions of lead to air from facilities

Emissions of lead to air by source

Key results

  • In 2021, 94.7 tonnes of lead were emitted in Canada
  • The largest source of lead emissions has been the non-ferrous smelting and refining industry since 1990. It accounted for 65% (or 62.0 tonnes) of total emissions in 2021
  • Between 1990 and 2021, lead emissions decreased by 91% (or 928.2 tonnes)

Lead emissions to air by source, Canada, 1990 to 2021

Lead emissions to air by source, Canada, 1990 to 2020 (see the data table below for the long description)
Data table for the long description
Lead emissions to air by source, Canada, 1990 to 2021
Year Non-ferrous refining and smelting industry
(emissions in tonnes)
Transportation (road, rail, air and marine)
(emissions in tonnes)
Manufacturing
(emissions in tonnes)
Iron and steel industry
(emissions in tonnes)
Mining and rock quarrying
(emissions in tonnes)
Other sources
(emissions in tonnes)
Total
(emissions in tonnes)
1990 886.28 13.71 42.94 54.92 0.00 25.04 1 022.89
1991 847.51 10.73 42.04 55.08 0.00 25.77 981.13
1992 899.27 9.46 41.07 55.14 0.00 25.74 1 030.68
1993 473.81 9.26 52.93 80.99 4.96 42.07 664.02
1994 1 010.17 8.60 46.67 83.41 6.15 58.52 1 213.53
1995 624.47 10.22 27.80 71.86 12.22 25.21 771.78
1996 698.38 10.69 14.49 74.38 14.12 29.07 841.12
1997 534.65 10.11 14.07 60.42 68.61 25.59 713.45
1998 454.48 10.75 12.50 54.13 78.60 25.34 635.79
1999 438.70 10.01 14.12 16.45 32.29 28.00 539.56
2000 443.50 10.13 13.66 8.32 41.91 28.48 546.00
2001 374.64 10.18 61.29 19.43 46.58 29.98 542.10
2002 331.64 10.23 7.84 17.09 53.40 33.36 453.56
2003 235.74 9.70 7.71 27.36 67.89 27.46 375.87
2004 177.81 8.31 12.28 25.42 67.52 19.32 310.65
2005 133.74 9.60 7.39 5.67 64.81 17.43 238.65
2006 170.87 8.65 5.75 5.89 66.10 18.34 275.60
2007 171.40 9.45 5.23 6.57 57.06 20.47 270.19
2008 161.10 9.56 4.68 5.99 43.87 22.57 247.76
2009 158.60 11.60 4.73 4.46 30.87 16.46 226.70
2010 131.68 11.81 3.80 6.28 19.74 18.84 192.14
2011 96.91 9.59 2.92 6.10 9.82 18.47 143.81
2012 88.77 12.45 2.91 6.68 7.10 11.82 129.72
2013 74.98 12.06 3.20 5.20 3.15 10.09 108.68
2014 87.03 11.21 3.66 6.11 0.90 10.45 119.36
2015 111.89 12.88 4.63 5.51 0.98 10.11 146.00
2016 113.12 13.96 3.83 5.21 1.13 10.53 147.78
2017 130.86 13.54 2.46 5.14 1.21 11.03 164.23
2018 112.16 12.50 4.02 6.20 1.64 9.60 146.12
2019 87.00 15.04 3.02 4.91 2.26 10.45 122.68
2020 82.36 12.64 2.52 4.79 1.41 9.19 112.91
2021 62.01 14.25 2.58 5.37 2.02 8.45 94.69

Note: Totals may not add up due to rounding. 

Download data file (Excel/CSV; 3.04 kB)

How this indicator was calculated

Note: The indicator reports emissions from human-related activities only. It does not include emissions from natural sources such as forest fires or volcanoes. The category "other sources" includes agriculture (livestock, crop production and fertilizer), building heating and energy generation, electric utilities, home firewood burning, incineration and waste, the oil and gas industry, other ore and mineral industries (the aluminum industry, the asphalt paving industry, the cement and concrete industry, foundries, iron pelletizing and the mineral products industry), paints and solvents, and other miscellaneous sources. For more details on the sources, consult the Data sources and methods.
Source: Environment and Climate Change Canada (2023) Air Pollutant Emissions Inventory.

The largest reduction in lead emissions between 1990 and 2021 was from the non-ferrous refining and smelting industry (89% or 824 tonnes). The decline was due to the introduction of pollution prevention plans and the installation of more efficient emission control equipment in operating smelters, along with the closure of outdated smelters in 2010 and 2019.

The majority of emissions prior to 2010 are attributed to a single non-ferrous refining and smelting facility in Manitoba. From 2014 to 2017, national lead emissions increased slightly; however, emissions decreased again from 2018 onwards. The main causes of the continued decrease in lead emission are pollution prevention plans and base-level industrial emissions requirements (BLIERs). Some fluctuations may be due to changes in lead concentrations in smelter feed, changes in production levels at some facilities and the closure of a smelter in New Brunswick in 2019.

Lead emissions to air by province and territory

Key results

  • In 2021, Quebec and Ontario accounted for 69% and 12% of national lead emissions, respectively
  • Between 1994 and 2021, Manitoba had the largest decrease in emissions of 503.5 tonnes

Lead emissions to air by province and territory, Canada, 1994, 2011 and 2021

Lead emissions to air by province and territory, Canada, 1994, 2010 and 2020 (see the data table below for the long description)
Data table for the long description
Lead emissions to air by province and territory, Canada, 1994, 2011 and 2021
Province or territory 1994
(emissions in tonnes)
2011
(emissions in tonnes)
2021
(emissions in tonnes)
Newfoundland and Labrador 0.39 1.77 2.54
Prince Edward Island 0.13 0.07 0.10
Nova Scotia 0.93 0.58 0.29
New Brunswick 10.46 17.59 1.94
Quebec 383.03 61.10 65.28
Ontario 109.12 47.99 11.66
Manitoba 504.83 2.62 1.33
Saskatchewan 5.60 1.30 1.62
Alberta 13.16 5.28 3.73
British Columbia 104.95 4.92 5.65
Yukon 0.22 0.14 0.11
Northwest Territories 0.54[A] 0.39 0.41
Nunavut n/a 0.06 0.03
Unspecified region[B] 80.17 n/a n/a
Canada 1 213.52 143.81 94.69

Note: n/a = not applicable. [A] Value for 1994 includes emissions from Nunavut, which was officially separated from the Northwest Territories in 1999. [B] Legacy data for 1994 cannot be attributed to any province or territory. Totals may not add up due to rounding.  

Download data file (Excel/CSV; 1.34 kB)

How this indicator was calculated

Note: Emissions from the Northwest Territories for 1994 includes emissions from Nunavut, which was officially separated from the Northwest Territories in 1999. The indicator reports emissions from human-related activities only. It does not include emissions from natural sources such as forest fires or volcanoes. Some reported emissions from Newfoundland and Labrador, Prince Edward Island, Nova Scotia, Saskatchewan, Yukon, the Northwest Territories and Nunavut are too small to see in the figure. Some legacy data for 1994 that cannot be attributed to any province or territory are excluded from the figure. To access all available years data please refer to the indicator’s interactive figures or, for the full dataset, to the Air Pollutant Emissions Inventory.
Source: Environment and Climate Change Canada (2023) Air Pollutant Emissions Inventory.

In 2021, Quebec had the highest lead emissions in Canada, accounting for 69% (or 65.3  tonnes) of national emissions. These emissions came mostly from the non-ferrous refining and smelting industry and accounted for 86% of the total provincial emissions.

For the most recent year, the largest source within each province and territory was:

  • the non-ferrous refining and smelting industry in New Brunswick, Ontario and Quebec
  • air transportation in British Columbia, Alberta, Saskatchewan, Manitoba, Prince Edward Island, the Northwest Territories, and Yukon
  • the mining and rock quarrying industry in Nunavut
  • the burning of home firewood in Nova Scotia
  • the iron ore industry in Newfoundland and Labrador

Between 1994 and 2021, while all provinces and territories had a decrease in lead emissions, Manitoba and Quebec experienced the largest decline in emissions (503.5 tonnes and 317.8 tonnes, respectively). These declines are mostly due to the reduced emissions from the non-ferrous refining and smelting industry.

New Brunswick and Newfoundland and Labrador had slight increases in lead emissions between 1994 and 2011, although emissions in New Brunswick declined between 2011 and 2021. With the exception of Quebec, emissions continued to decrease or remained stable from 2011 to 2021 in most provinces. Ontario had the largest decrease in emissions (36.3 tonnes) between 2011 and 2021, largely from the non-ferrous refining and smelting industry. This decrease was mostly due to changes in production levels and the introduction of pollution prevention activities.

Lead emissions to air from facilities

The National Pollutant Release Inventory provides detailed information on emissions from industrial, commercial and institutional facilities that meet its reporting criteria.

The Canadian Environmental Sustainability Indicators provide access to this information through an online interactive map. The map allows you to explore lead emissions to air from individual facilities.

In 2021, facility-reported lead emissions represent 82% of total national lead emissions.Footnote 4  Of these facilities:

  • 121 facilities reported emissions under 0.5 kilogram (kg)
  • 200 facilities reported emissions between 0.5 to 120 kg
  • 35 facilities reported emissions over 120 kg, which were located in British Columbia (1), Saskatchewan (2), Manitoba (2), New Brunswick (2), Newfoundland and Labrador (2), Alberta (3), Ontario (11) and Quebec (12)
    • One (1) non-ferrous smelting and refining facility in Quebec accounted for 70% (or 54 516 kg) of the total facility-reported lead emissions in 2021

Lead emissions to air by facility, Canada, 2021

Lead emissions to air by facility, Canada, 2020 (see the long description below)
Long description

The map of Canada shows the amount of lead in kilograms emitted to air in 2021 by facility. Facilities are categorized by the amount of lead emitted. The categories are: less than 0.5 kilograms, 0.5 to less than 5 kilograms, 5 to less than 20 kilograms, 20 to less than 50 kilograms, 50 to less than 200 kilograms and 200 to 54 516 kilograms.

Data for the map

Navigate data using the interactive map

How this indicator was calculated

Source: Environment and Climate Change Canada (2023) National Pollutant Release Inventory.

Cadmium

Emissions of cadmium to air

Cadmium is a naturally occurring metal in the Earth's crust. It can be released during natural processes, such as weathering and erosion of cadmium-bearing rocks, forest fires and volcanic activity. Human activity can also contribute to cadmium emissions, such as the manufacture of batteries, electroplating, power generation and heating, transportation, solid waste disposal and sewage sludge application.

Exposure to cadmium can be hazardous to both humans and wildlife since it accumulates in the food chain over time. The Government of Canada concluded cadmium compounds may be harmful to the environment and may constitute a danger based on their carcinogenic potential. Exposure to cadmium has been associated with gastrointestinal irritation and harmful effects to the kidneys and bones.

Emissions of cadmium to air by source
Emissions of cadmium to air by province and territory
Emissions of cadmium to air from facilities

Emissions of cadmium to air by source

Key results

  • In 2021, 4.5 tonnes of cadmium were emitted in Canada
  • Since 1990, the largest source of cadmium emissions has been the non-ferrous refining and smelting industry. It accounted for 49% (or 2.2 tonnes) of the national total in 2021
  • Between 1990 and 2021, cadmium emissions decreased by 94% (or 76.7 tonnes)

Cadmium emissions to air by source, Canada, 1990 to 2021

Cadmium emissions to air by source, Canada, 1990 to 2020 (see the data table below for the long description)
Data table for the long description
Cadmium emissions to air by source, Canada, 1990 to 2021
Year Non-ferrous refining and smelting industry
(emissions in tonnes)
Building heating and energy generation
(emissions in tonnes)
Mining and rock quarrying
(emissions in tonnes)
Incineration and waste
(emissions in tonnes)
Other sources
(emissions in tonnes)
Total
(emissions in tonnes)
1990 78.29 0.90 0.00 0.08 1.91 81.18
1991 67.85 0.90 0.00 0.08 1.94 70.77
1992 69.20 0.90 0.00 0.08 2.01 72.20
1993 11.95 0.92 0.00 0.08 2.07 15.02
1994 72.31 0.97 0.47 0.08 2.11 75.93
1995 16.73 1.02 0.57 0.08 2.40 20.80
1996 24.15 1.04 0.46 0.08 2.24 27.97
1997 40.34 1.03 0.70 0.08 2.18 44.33
1998 41.58 0.90 0.57 0.08 2.03 45.16
1999 36.16 0.94 0.48 0.08 2.30 39.97
2000 33.53 1.02 0.55 0.09 1.84 37.03
2001 64.69 0.98 0.53 0.09 1.95 68.25
2002 35.06 1.02 0.76 0.14 2.52 39.50
2003 24.43 1.05 2.59 0.04 3.40 31.51
2004 26.43 1.02 2.57 0.04 3.46 33.52
2005 28.59 0.99 2.91 0.04 2.11 34.63
2006 34.77 0.93 2.87 0.04 2.04 40.66
2007 22.37 1.01 2.87 0.03 2.32 28.60
2008 17.38 1.02 2.03 0.07 2.19 22.68
2009 16.02 0.96 1.69 0.03 2.36 21.06
2010 12.27 0.95 0.86 0.04 2.21 16.33
2011 4.84 1.02 0.31 0.03 2.28 8.48
2012 6.28 1.00 0.33 0.02 1.97 9.60
2013 5.30 0.96 0.32 0.03 1.88 8.49
2014 4.56 0.95 0.33 0.02 1.71 7.58
2015 5.02 0.93 0.05 0.02 1.53 7.55
2016 5.10 0.95 0.05 0.01 1.53 7.65
2017 4.28 0.98 0.05 0.02 1.50 6.83
2018 4.23 0.99 0.10 0.02 1.51 6.86
2019 3.96 1.00 0.07 0.03 1.42 6.48
2020 1.81 0.94 0.06 0.04 1.28 4.12
2021 2.21 0.92 0.05 0.04 1.26 4.47

Note: Totals may not add up due to rounding. 

Download data file (Excel/CSV; 2.51 kB)

How this indicator was calculated

Note: The indicator reports emissions from human-related activities only. It does not include emissions from natural sources such as forest fires or volcanoes. The category "other sources" includes agriculture (livestock, crop production and fertilizer), electric utilities, home firewood burning, manufacturing, the oil and gas industry, other ore and mineral industries (the aluminum industry, the asphalt paving industry, the cement and concrete industry, foundries, the iron and steel industry and iron pelletizing), paints and solvents, transportation (road, rail, air and marine) and other miscellaneous sources. For more details on the sources, consult the Data sources and methods.
Source: Environment and Climate Change Canada (2023) Air Pollutant Emissions Inventory.

Between 1990 and 2021, cadmium emissions from the non-ferrous refining and smelting industry declined by 97% (76.1 tonnes). The declines in emissions from this industry were responsible for nearly 100% of the total reduction in national cadmium emissions between 1990 and 2021. This decline was due to the closure of outdated smelters in 2010 and 2019 and the introduction of pollution prevention plans, in addition to the collateral benefits from environmental performance agreements.

The fluctuations in cadmium emissions prior to 2010 are mostly driven by emissions from a single non-ferrous refining and smelting facility in Manitoba. 

Cadmium emissions to air by province and territory

Key results

  • In 2021, Ontario and Quebec accounted for 68% (3.1 tonnes) of national cadmium emissions
  • Between 1994 and 2021, Manitoba had the largest decline in emissions (59.6 tonnes)

Cadmium emissions to air by province and territory, Canada, 1994, 2011 and 2021

Cadmium emissions to air by province and territory, Canada, 1994, 2010 and 2020 (see the data table below for the long description)
Data table for the long description
Cadmium emissions to air by province and territory, Canada, 1994, 2011 and 2021
Province or territory 1994
(emissions in tonnes)
2011
(emissions in tonnes)
2021
(emissions in tonnes)
Newfoundland and Labrador 0.03 0.09 0.07
Prince Edward Island 0.01 0.01 0.01
Nova Scotia 0.07 0.09 0.04
New Brunswick 1.94 1.43 0.16
Quebec 5.39 1.76 1.69
Ontario 2.40 3.19 1.37
Manitoba 59.78 0.39 0.15
Saskatchewan 0.11 0.07 0.08
Alberta 0.36 1.04 0.49
British Columbia 4.74 0.39 0.41
Yukon < 0.01 < 0.01 < 0.01
Northwest Territories 0.01[A] 0.01 0.01
Nunavut n/a < 0.01 < 0.01
Unspecified region[B] 1.07 n/a n/a
Canada 75.93 8.48 4.47

Note: n/a = not applicable. [A] Value for 1994 includes emissions from Nunavut, which was officially separated from the Northwest Territories in 1999. [B] Legacy data for 1994 cannot be attributed to any province or territory. Totals may not add up due to rounding. 

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How this indicator was calculated

Note: Emissions from the Northwest Territories for 1994 includes emissions from Nunavut, which was officially separated from the Northwest Territories in 1999. The indicator reports emissions from human-related activities only. It does not include emissions from natural sources such as forest fires or volcanoes. Some reported emissions from Newfoundland and Labrador, Prince Edward Island, Nova Scotia, Manitoba, Saskatchewan, Yukon, the Northwest Territories and Nunavut are too small to see in the figure. Legacy data for 1994 that cannot be attributed to any province or territory are excluded from the figure. To access all available years data please refer to the indicator’s interactive figures or, for the full dataset, to the Air Pollutant Emissions Inventory.
Source: Environment and Climate Change Canada (2023) Air Pollutant Emissions Inventory.

In 2021, Ontario and Quebec reported the highest cadmium emissions of the provinces and territories, accounting for 31% (1.4 tonnes) and 38% (1.7 tonnes) of national emissions, respectively. These emissions came mostly from the non-ferrous refining and smelting industry, manufacturing industries, and building heating and energy generation.

For 2021, the largest source within each province and territory was:

  • the non-ferrous refining and smelting industry in British Columbia, Manitoba, Ontario, Quebec and New Brunswick
  • building heating and energy generation in Alberta, Saskatchewan, Nova Scotia, Prince Edward Island, the Northwest Territories, and Yukon
  • the iron ore industry in Newfoundland and Labrador
  • incineration and waste in Nunavut

Between 1994 and 2021, all provinces and territories, with the exception of Alberta and Newfoundland and Labrador, had experienced a decline in emissions or remained stable. During this time period, Manitoba experienced the largest decline in cadmium emissions (59.6 tonnes).

While Ontario, Alberta, Nova Scotia and Newfoundland and Labrador had higher cadmium emissions in 2011 compared to 1994, emissions from all provinces and territories continued to decrease or remained stable from 2011 to 2021. Ontario experienced the largest decline between 2011 and 2021 (1.8 tonnes), largely from the non-ferrous refining and smelting industry. This decrease was mostly due to changes in production levels and the introduction of pollution prevention activities

Cadmium emissions to air from facilities

The National Pollutant Release Inventory provides detailed information on emissions from industrial, commercial and institutional facilities that meet its reporting criteria.

The Canadian Environmental Sustainability Indicators provide access to this information through an online interactive map. The map allows you to explore cadmium emissions to air from individual facilities.

In 2021, facility-reported cadmium emissions represent 74% of total national cadmium emissions.Footnote 4  Of these facilities:

  • 115 facilities reported emissions under 0.5 kilogram (kg)
  • 115 facilities reported emissions between 0.5 to 20 kg
  • 18 facilities reported emissions over 20 kg, which were located in British Columbia (1), Manitoba (1), New Brunswick (1), Newfoundland and Labrador (1), Ontario (3), Alberta (5), and Quebec (6)

Cadmium emissions to air by facility, Canada, 2021

Cadmium emissions to air by facility, Canada, 2020 (see the long description below)
Long description

The map of Canada shows the amount of cadmium in kilograms emitted to air in 2021 by facility. Facilities are categorized by the amount of cadmium emitted. The categories are: less than 0.05 kilograms, 0.05 to less than 0.5 kilograms, 0.5 to less than 2.5 kilograms, 2.5 to less than 5 kilograms, 5 to less than 20 kilograms and 20 to 812 kilograms.

Data for the map

Navigate data using the interactive map

How this indicator was calculated

Source: Environment and Climate Change Canada (2023) National Pollutant Release Inventory.

About the indicators

About the indicators

What the indicators measure

These indicators track human-related emissions to air of 3 substances that are defined as toxic under the Canadian Environmental Protection Act, 1999: mercury, lead and cadmium and their compounds. For each substance, data are provided at the national, regional (provincial and territorial) and facility level and by source. Global emissions data are also provided for mercury.

Why these indicators are important

Mercury and its compounds, lead and inorganic cadmium compounds are on the Toxic substances list under Schedule 1 of the Canadian Environmental Protection Act, 1999. This means that these substances are "entering or may enter the environment in a quantity or concentration or under conditions that (a) have or may have an immediate or long-term harmful effect on the environment or its biological diversity; (b) constitute or may constitute a danger to the environment on which life depends; or (c) constitute or may constitute a danger in Canada to human life or health."

The indicators inform Canadians about emissions to air of these 3 substances from human activity in Canada. These indicators also help the government to identify priorities and develop or revise strategies to inform further risk management and to track progress on policies put in place to reduce or control these 3 substances and air pollution in general.

Related initiatives

These indicators support the measurement of progress towards the following 2022 to 2026 Federal Sustainable Development Strategy Goal 11: Improve access to affordable housing, clean air, transportation, parks, and green spaces, as well as cultural heritage in Canada. 

In addition, the indicators contribute 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."

Related indicators

The Releases of harmful substances to water indicators track human-related releases to water 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.

The Human exposure to harmful substances indicators track the concentrations of 4 substances (mercury, lead, cadmium and bisphenol A) in Canadians.

The 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. Mercury, lead and cadmium can also be components of particulate matter. For each air pollutant, data are provided at the national, provincial/territorial and facility level and by major source.

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.

Data sources and methods

Data sources and methods

Data sources

Data for the indicators are based on emission estimates reported in the Air Pollutant Emissions Inventory. The inventory data are available online on the Open Data website. Facility data for the interactive maps come from the National Pollutant Release Inventory, which are also available on Open Data.

Global mercury emissions data were taken from the United Nations Environment Programme's Global Mercury Assessment 2018 report.

More information

Air Pollutant Emissions Inventory

Canada's Air Pollutant Emissions Inventory is prepared and published by Environment and Climate Change Canada. The inventory provides data and estimates on releases of air pollutants from human activities. These pollutants contribute to the issues of smog, acid rain, reduced air quality and climate change. Improvements to the inventory are made periodically as new emission estimation methods are adopted and additional information is made available. Historical emissions are updated on the basis of these improvements.

This inventory fulfills many of Canada's international reporting obligations on pollution. It is a comprehensive inventory of 17 air pollutantsFootnote 7  that combines facility emissions reported to the National Pollutant Release Inventory with non-facility emissions estimated by Environment and Climate Change Canada (the department). Estimates are developed using the latest estimation methods and are largely based on published statistics or other sources of information, such as surveys and reports. The Air Pollutant Emissions Inventory provides a comprehensive overview of pollutant emissions across Canada.

The national and provincial/territorial inventory data are current as of March 15, 2023. While the national indicators cover the period from 1990 to 2021, the provincial/territorial indicators only cover the period from 1994 to 2021. Data from 1990 to 1993 were not considered in the provincial/territorial indicators as a significant amount of legacy emissions could not be attributed to any province or territory. Emissions data are reported in the inventory approximately 1 year after data collection, validation, calculation and interpretation have been completed. The indicators are reported following the public release of the inventory data.

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 for these facilities are provided by the facility operators as mandated by the Canadian Environmental Protection Act, 1999. 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 that meet substance-specific reporting thresholds and other requirements must report their pollutant releases, disposals and transfers annually to the department. The inventory data for 2021 are current as of March 30, 2023.

Global Mercury Assessment

The Global Mercury Assessment 2018 report is the third edition of the United Nations Environment Programme reporting on global mercury emissions. This edition was based on national emissions inventories for 2015. Data for global mercury emissions were taken directly from the Global Mercury Assessment 2018 report.

Methods

The indicators are produced by grouping the calculated emissions data from Canada's national inventories to report on the key sources that contribute to the majority of mercury, lead and cadmium emissions.

More information

Compilation of 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 and models 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. Environment and Climate Change Canada (the department) collects most facility-reported data through 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.

Within the Air Pollutant Emissions Inventory, 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 National Pollutant Release 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 are estimated by the department to ensure complete coverage. 

In-house emission estimates

Emissions estimates are calculated by the department using information such as production data and activity data, using various estimation methodologies and emission models. These emission estimates are at the national level rather than at any specific geographic locations. 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 8  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 9

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 section A2-4 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 type.

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 Chapter 3.7 and 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 Chapter 3.4 of the Air Pollutant Emissions Inventory Report.

Temporal coverage

Historical data are provided at the national and source level for the period from 1990 to 2021. For the regional indicators (provincial/territorial), emissions are presented for 1994, 2011 and 2021. However, because Nunavut only officially separated from the Northwest Territories in 1999, emissions from the Northwest Territories for 1994 include emissions from the region that would eventually become Nunavut.

Air pollutant emissions by source classification

For the purposes of reporting the indicators, calculated emissions data from the Air Pollutant 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 sources of harmful substances reported in the indicators compared with the sources and sectors reported by the Air Pollutant Emissions Inventory..

Table 1. Alignment of sources reported in the indicators with the sources and sectors from the Air Pollutant Emissions Inventory
Sources in the indicators Sources and sectors in the Air Pollutant 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: Agricultural fuel combustion
Building heating and energy generation Commercial/residential/institutional: Commercial and institutional fuel combustion
Building heating and energy generation Commercial/residential/institutional: Construction 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 sources: Crematoriums
Incineration and waste Incineration and waste sources: Waste incineration
Incineration and waste Incineration and waste sources: Waste treatment and disposal
Manufacturing Manufacturing: Abrasives manufacturing
Manufacturing Manufacturing: Bakeries
Manufacturing Manufacturing: Biofuel production
Manufacturing Manufacturing: Chemicals industry
Manufacturing Manufacturing: Electronics
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: Service stations
Miscellaneous Commercial/residential/institutional: Other (commercial/residential/institutional)
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[C]
Ore and mineral industries Ore and mineral industries: Foundries
Ore and mineral industries Ore and mineral industries: Iron and steel industry[C]
Ore and mineral industries Ore and mineral industries: Iron pelletizing
Ore and mineral industries Ore and mineral industries: Mineral products industry
Ore and mineral industries Ore and mineral industries: Mining and rock quarrying[C]
Ore and mineral industries Ore and mineral industries: Non-ferrous refining and smelting industry[C]
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 (landing and takeoff)
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
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. [C] These sectors from the Air Pollutant Emissions Inventory are sometimes shown as individual sources in the indicators when they have significant emissions. The sectors may vary from one substance to the next.

For display purposes, smaller emitting sources are sometimes grouped together under the title "Other sources" in the figures and corresponding data tables of emissions by source. The grouped sources may differ by substance and are listed in the notes of each figure and data table.

Recent changes

The emission estimates reported in the Air Pollutant Emissions Inventory used in the indicators have undergone a number of significant recalculations. Specifically, the sector emissions for ore and mineral industries, the oil and gas industry, manufacturing, transportation, agriculture, commercial/residential/institutional, and incineration and waste, following the implementation of updates or improvements to quantification methods. As a result, emissions reported in this indicator may be different from previous years. For more information about these recent changes, consult Annex 3 of the Air Pollutant Emissions Inventory Report.

Caveats and limitations

Total emissions of mercury, lead and cadmium to air reported in these indicators exclude natural sources such as forest fires or volcanoes.

To provide a consistent global picture, Canadian mercury emissions data used for the international comparison came from the United Nations Environment Programme's Global Mercury Assessment 2018 report. However, it is important to note that the emissions data found in this report were estimated using different estimation techniques and different source classifications than the data used for the national indicators. In addition, some sources were not quantified in the international comparison due to a lack of data.

The methods used to estimate air pollutant emissions continue to evolve. In general, improvements are made every year to methodologies for estimating emissions. As a result of these improvements, emissions for a given year may differ from those previously published by the department. Caution is advised when comparing different reports and different sources.

Prior to the launch of the National Pollutant Release Inventory, emissions data were collected and compiled by provincial, territorial and regional environmental authorities. As such, in the provincial/territorial comparisons in the indicators, the base year used differs from that used in the national indicators. Furthermore, some legacy data for 1994 could not be attributed to any province or territory. The legacy data were captured under unspecified region in the data tables.

The latest year reported (2021) coincides with the second year of the COVID-19 pandemic which had an impact on a wide range of economic sectors, especially the energy and transport sectors. The emissions change must be interpreted with caution as the impact of the pandemic on the emissions is not discussed in detail.

More information

Air Pollutant Emissions Inventory and National Pollutant Release Inventory

The Air Pollutant Emissions Inventory uses facility information from the National Pollutant Release Inventory and other sources. The National Pollutant Release Inventory started providing facility-reported data to the Air Pollutant Emissions Inventory for heavy metals (mercury, lead and cadmium) in 1994. 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 any given time because of updates or corrections to the facility-reported data from the National Pollutant Release Inventory.

The number and composition of facilities that report releases to air to the National Pollutant Release Inventory can vary each year. This variation is due to the fact that only facilities that meet or exceed the reporting threshold are required to report to the inventory. An analysis of how this might affect the apparent trends has not been undertaken. Events or changes at facilities can also alter facility emissions outputs from one year to the next. Some of changes can include: 

  • changes in production levels
  • upgrades to operating practices
  • plant expansions
  • change of ownership
  • temporary or permanent closures
  • pollution prevention measures
  • accidental releases

Facilities reporting to the National Pollutant Release Inventory may use different methods to calculate releases. The methods vary depending on the substance and/or facility and may change from year to year.

Since the launch of the National Pollutant Release Inventory in 1993, the substance list and reporting requirements have continuously evolved.

Global mercury emissions

Air emissions sources that were not quantified in the international mercury emissions comparison include:

  • chemical manufacturing processes
  • other mineral products (for example, lime manufacturing)
  • secondary non-ferrous metal production
  • oil and gas extraction
  • pulp and paper industry
  • food industry
  • transport and processing other than refinery emissions
  • industrial/hazardous waste incineration and sewage sludge incineration
  • preparation of dental amalgam fillings and disposal of removed fillings containing mercury

The Canadian mercury emissions data follows the same reporting structure as the Global Mercury Assessment report and uses the best data, measurements and methods available. Nonetheless, users must be cautious when comparing the data, as emissions estimation methodologies differ among countries

Resources

Resources

References

Environment and Climate Change Canada (2016). Canadian Mercury Science Assessment Report. Retrieved on August 9, 2023.  

United Nations Environment Programme (2019) Global Mercury Assessment 2018. Retrieved on June 14, 2023.

Environment and Climate Change Canada (2023) Canada's Air Pollutant Emissions Inventory. Retrieved on June 16, 2023.

Environment and Climate Change Canada (2023) National Pollutant Release Inventory bulk data. Retrieved on June 15, 2023.

Environment and Climate Change Canada (2023) Using and interpreting data from the National Pollutant Release Inventory. Retrieved on June 15, 2023.

Interactive figures
Updated October 2023

These interactive figures support the Emissions of harmful substances to air indicator. Use them to explore the latest emissions of cadmium, lead and mercury 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.

Note: The charts are defaulted to show the national total and trends. When filtering for multiple provinces and territories, the cumulative total and trends will be reflected on the chart. Analysis of long-term regional trends should be interpreted with caution. Legacy data prior to 2005 could not be attributed to any province or territory and are classified as emissions from an unspecified region. The fluctuations in lead and cadmium emissions prior to 2010 are mostly driven by emissions from a single non-ferrous refining and smelting facility in Manitoba.
Source: Environment and Climate Change Canada (2023) Air Pollutant Emissions Inventory.

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