The Appendix is intended for use in conjunction with the 2021 Annual Air Quality in Ontario Report. The Appendix briefly describes the provincial Air Quality Health Index (AQHI) network, quality assurance and quality control procedures, and the Ministry of the Environment, Conservation and Parks’ air quality database. It also includes a series of tables displaying station locations and a listing of the summary statistics including means, maximums, percentile values and the number of exceedances of the Ontario Ambient Air Quality Criteria (AAQC) for each pollutant. In addition, trends for select common pollutants are displayed for a 10-year period, whereas trends for select research parameters are displayed for a 6-year period.

Monitoring network operations

Network description

In 2021, the ministry operated 39 ambient air monitoring sites across Ontario as part of the AQHI network. The AQHI network was comprised of 134 continuous monitoring instruments at 39 sites. These instruments have the capability of recording minute data (approximately 70 million data points per year) that are used to scan and validate the continuous hourly data.

Quality assurance and quality control

Day-to-day maintenance and support of the instruments are administered by ministry staff. Instrumentation precision is verified by daily automatic internal zero and span checks. Data analysts and station operators review span control charts to confirm instrument precision using a telemetry system. A quarterly quality assurance and quality control (QA/QC) review is performed on the ambient data set to highlight anomalies and administer corrective action in a timely manner.

The air monitoring station operators routinely inspect and maintain monitoring equipment and stations with mandatory quarterly on-site visits where secondary transfer standards are used to calibrate instrumentation. Station maintenance activities are recorded using Fieldworker Inc. software, an electronic documentation solution; this information is transferred directly to the ministry’s database. The instrumentation used throughout the provincial air monitoring network has been standardized to Thermo Electron Corporation analyzers to streamline parts inventory and leverage common hardware used within each analyzer. The following is a summary of the instrumentation deployed within the network and are all US EPA designated equivalent methods:

  • Nitrogen Oxides – TE42C/I
  • Fine Particulate Matter – SHARP 5030
  • Ozone – TE49C/I
  • Sulphur Dioxide – TE43I
  • Carbon Monoxide – TE48I
  • Total Reduced Sulphur – TE43I/CDN101

The ministry operates a laboratory with gas reference standards that adhere to those of the U.S. National Institute of Standards and Technology (NIST) and the Air Quality Research Division of Environment and Climate Change Canada. The secondary transfer standards used by station operators are referenced and certified to the ministry’s NIST primary standards on a quarterly basis.

The TRAP instrumentation used throughout the roadside air monitoring network include:

  • Ultrafine Particles – Teledyne API Model 651
  • Black Carbon in PM2.5 – Magee Scientific AE33 Aethalometer
  • Heavy Metals in PM2.5 – Cooper Environmental Xact 625
  • Major Components in PM2.5 – Aerodyne Quadrupole Aerosol Chemical Speciation Monitor (ACSM)

The Ontario ambient air quality monitoring network undergoes constant maintenance to ensure a high standard of quality control. Continuous real-time data are consistently reviewed, assessed and validated by ministry staff. Immediate actions are taken to correct any inconsistencies that may affect the validity of the data. These measures ensure ambient air monitoring data are valid, complete, comparable, representative and accurate. As a result, the 2021 ambient air quality monitoring network had 98.6% valid data from over one million hourly data points.

Data base

The ambient air quality data used in this report are stored in the ministry’s air quality information system (AQUIS) and are made available through the Air Quality Ontario web site, and the Ontario Data Catalogue. A statistical pattern test is used to identify data anomalies, such as unusual pollutant concentrations. Each pollutant has a predetermined concentration range based on historical data. Values outside this range are flagged for further investigation.

Data are obtained from automated ambient air monitoring instruments that operate continuously to produce an average measurement for every hour for a possible total of 8,760 measurements in a given year. Hourly parameters measured include NO/NO2/NOx, PM2.5, O3, SO2, CO and TRS compounds. An annual mean requires at least 6,570 hourly readings. In addition, each quarter of the year should have 75% valid data for PM2.5, whereas for ozone, only the 2nd and 3rd quarters of the year require 75% valid data based on protocols that are consistent with the Canadian Council of Ministers of the Environment (CCME) and the United States Environmental Protection Agency (U.S. EPA). For VOC samples, half of the method detection limit (MDL) is applied as appropriate to concentrations measured below the detection limit. An annual and/or monthly mean for 24-hour VOC samples requires 50% of valid samples. The 50% data requirement also applies to the research parameters (ultrafine particles, black carbon and trace metals and major components of PM2.5).

Network descriptive table

The AQHI network for 2021 is summarized in the 2021 Ontario Continuous Ambient Air Monitoring Network. The table displays the station name, numerical identifier and pollutants measured. The numerical identifier is the station (ID) number, the first digit of which identifies the geographic region in which the station is located. Air monitoring stations within the AQHI network can measure up to six common pollutants (NO2, PM2.5, ozone, SO2, CO and TRS compounds) based on the pollutant(s) of concern for the regional area it represents.

The 2021 Ontario Continuous Ambient Air Monitoring Network also identifies the type of air monitoring site: ambient, roadside, Canadian Ambient Air Quality Standard (CAAQS), and/or National Air Pollution Surveillance (NAPS). Ambient sites represent the general air quality of an area without any direct influence of local industrial sources. Road-side sites are typically within approximately 100 m of a major roadway with daily traffic volumes greater than 10,000 vehicles per day.

Annual statistics and trends

The annual statistical data and trends for various continuous pollutants and selected volatile organic compounds are presented in the Appendix. The annual averages, maximums and percentiles are displayed in the annual statistics tables. (A percentile is the value equal to or below which a given percentage of the data set falls. For example, if 70% of the data are equal to or below 0.10 ppm, the 70th percentile is 0.10 ppm).

The trends are calculated from monthly means through the Mann-Kendall (M-K) test. The M-K test is a nonparametric statistical approach that can be applied to data without making assumptions on the nature of the data distribution. The M-K test is essentially a test for uniform progression (zero change) in the slope of the linear regression of time-ordered data versus time (Gilbert, 1987). The M-K test is particularly suitable for environmental monitoring data since missing, trace and below detection limit values can be handled. This test can also be used to compare trends at multiple stations. The seasonal Kendall test, also performed in this Report, is a generalization of the M-K test (Gilbert, 1987) for use to determine the true trend when there are seasonal cycles in the data which do not constitute a true long-term trend. The change over time was based on the Sen’s slope, also known as the Thiel-Sen’s estimator of linear trend. The Sen’s slope is closely related to and applied in conjunction with the M-K Test. Compared to the common least squares regression, the Sen’s slope procedure is a nonparametric method for computing the value of the true slope when there are gross errors or outliers in the data without making assumptions of a normal distribution on the data (Gilbert, 1987).

Other informative tables

Calculated CAAQS metrics for PM2.5, ozone, NO2 and SO2 are presented for 2021 (based on a three-year average, 2019-2021) and over a 10-year period in Canadian Ambient Air Quality Standard Reporting. The air zone management levels associated to each CAAQS reporting pollutant are also provided for reference. The percentage distribution of hourly AQHI readings within the various health risk categories for each of the 39 monitoring sites, and the number of air quality alerts issued in Ontario during 2021 are summarized in AQHI and Air Quality Alert Program Reporting.

2021 air monitoring network

2021 Ontario continuous ambient air monitoring network
ID Station name Station location Year Latitude Longtiude Air intake Type AQHI NO2 PM2.5 O3 SO2 CO TRS
12008 Windsor Downtown 467 University Ave. W. 1969 42°18'58.8" -83°02'37.2" 4 A/RS/C/N Y T T T T T N/A
12016 Windsor West College Ave./South St. 1975 42°17'34.4" -83°04'23.3" 4 A/RS/N Y T T T T N/A T
13001 Chatham 435 Grand Ave. W. 2005 42°24'13.3" -82°12'29.9" 15 A/C/N Y T T T N/A N/A N/A
14111 Sarnia 700 Christina St. N. 2016 42°59'25.0" -82°23'43.2" 3 A/C/N Y T T T T N/A T
15020 Grand Bend Point Blake Conservation Area 1991 43°19'59.1" -81°44'34.4" 5 A/N Y T T T N/A N/A N/A
15026 London 42 St. Julien St. 2013 42°58'28.1" -81°12'03.1" 5 A/C/N Y T T T N/A N/A N/A
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plant 2002 42°40'19.5" -81°09'46.4" 5 A/N Y T T T N/A N/A N/A
18007 Tiverton 4th Concession/Bruce Rd. 23 1979 44°18'52.1" -81°32'59.0" 4 A/N Y N/A T T N/A N/A N/A
21005 Brantford 324 Grand River Ave. 2004 43°08'19.0" -80°17'33.5" 5 A/C/N Y T T T N/A N/A N/A
26060 Kitchener West Ave./Homewood Ave. 1990 43°26'37.8" -80°30'13.7" 5 A/C/N Y T T T N/A N/A N/A
27067 St. Catharines Argyle Cres., Pump Stn. 1987 43°09'36.2" -79°14'05.1" 4 A/C/N Y T T T N/A N/A N/A
28028 Guelph Exhibition St./Clark St. W. 2000 43°33'05.8" -80°15'51.0" 4 A/C/N Y T T T N/A N/A N/A
29000 Hamilton Downtown Elgin St./Kelly St. 1987 43°15'28.0" -79°51'42.0" 4 A/RS/C/N Y T T T T T T
29118 Hamilton West Main St. W./Hwy 403 1985 43°15'26.8" -79°54'27.9" 3 A/RS/N Y T T T N/A N/A N/A
29214 Hamilton Mountain 250 Fennell Ave. W. 2019 43°14'28.4" -79°53'21.9" 3 A/C/N Y T T T T N/A N/A
31129 Toronto Downtown 55 John St., Metro Hall 2019 43°38'43.5" -79°23'20.7" 2 A/RS/C/N Y T T T N/A N/A N/A
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 1970 43°44'52.5" -79°16'26.6" 4 A/RS/C/N Y T T T N/A N/A N/A
34021 Toronto North 4905 Dufferin St., ECCC 1988 43°46'53.8" -79°25'03.8" 5 A/RS/C/N Y T T T T T N/A
35125 Toronto West 125 Resources Rd. 2003 43°42'34.0" -79°32'36.6" 8 A/RS/C/N Y T T T T T N/A
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 1979 43°18'54.4" -79°48'09.5" 5 A/C/N Y T T T N/A N/A N/A
44017 Oakville EightLine/Glenashton Dr., Halton Reservoir 2003 43°29'12.9" -79°42'08.2" 12 A/C/N Y T T T N/A N/A N/A
44029 Milton 1120 Main St. E. 2019 43°31'46.7" -79°51'44.8" 4 A/C/N Y T T T T N/A N/A
45027 Oshawa Brittania Ave. W., Ep Taylor Stables 2005 43°57'07.5" -78°54'45.2" 7 A/C/N Y T T T N/A N/A N/A
46090 Brampton 109 Mclaughlin Rd. S. 2000 43°41'55.5" -79°46'51.3" 5 A/C/N Y T T T N/A N/A N/A
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 2007 43°32'49.1" -79°39'31.3" 5 A/C/N Y T T T N/A N/A N/A
47045 Barrie 83 Perry St. 2001 44°22'56.5" -79°42'08.3" 5 A/C/N Y T T T N/A N/A N/A
48006 Newmarket Eagle St. W./Mccaffrey Rd. 2001 44°02'39.5" -79°28'59.7" 5 A/N Y T T T N/A N/A N/A
49005 Parry Sound 7 Bay St. 2001 45°20'16.3" -80°02'17.4" 5 A/N Y T T T N/A N/A N/A
49010 Dorset 1026 Bellwood Acres Rd. 1981 45°13'27.4" -78°55'58.6" 3 A/N Y N/A T T N/A N/A N/A
51001 Ottawa Downtown Rideau St./Wurtemburg St. 1971 45°26'03.6" -75°40'33.6" 4 A/C/N Y T T T T T N/A
51010 Petawawa Petawawa Research Forest Facility 2007 45°59'48.2" -77°26'28.3" 6 A/N Y N/A T T N/A N/A N/A
52023 Kingston 23 Beechgrove Lane 2014 44°13'11.5" -76°31'16.1" 5 A/C/N Y T T T N/A N/A N/A
54012 Belleville 2 Sidney St., Water Treatment Plant 2002 44°09'01.9" -77°23'43.8" 10 A/N Y T T T N/A N/A N/A
56051 Cornwall Bedford St./3rd St. W. 1970 45°01'04.7" -74°44'06.8" 4 A/N Y T T T N/A N/A N/A
59006 Peterborough 10 Hospital Dr. 1998 44°18'06.9" -78°20'46.4" 10 A/C/N Y T T T N/A N/A N/A
63203 Thunder Bay 421 James St. S. 2004 48°22'45.8" -89°17'24.6" 15 A/RS/C/N Y T T T N/A N/A N/A
71078 Sault Ste. Marie Sault College 2004 46°31'59.5" -84°18'35.7" 8 A/C/N Y T T T T N/A T
75010 North Bay Chippewa St. W., Dept. National Defence 1979 46°19'23.5" -79°26'57.4" 4 A/RS/N Y T T T N/A N/A N/A
77233 Sudbury 155 Elm St. 2013 46°29'31.0" -81°00'11.2" 3 A/C/N Y T T T T N/A N/A
Total               39 36 39 39 11 5 4

Notes:

ID
station identfication number
Year
year station began monitoring
Air intake
height of air intake above ground (m)
Type
type of monitoring site
A
ambient
RS
road-side
C
Canadian Ambient Air Quality Standard (CAAQS)
N
National Air Pollution Surveillance (NAPS)
AQHI
Air Quality Health Index
T
telemetry
NO2
nitrogen dioxide
PM2.5
fine particulate matter
O3
ground-level ozone
SO2
sulphur dioxide
CO
carbon monoxide
TRS
total reduced sulphur
Y
yes

2021 annual statistics

2021 nitric oxide (NO) annual statistics

Unit: parts per billion (ppb)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Max 1h Max 24h
12008 Windsor Downtown 467 University Ave. W. 8688 0.3 0.5 0.9 1.60 4.1 33.8 2.5 219.8 43.6
12016 Windsor West College Ave./South St. 8636 0.0 0.2 0.5 1.10 3.6 40.0 2.3 143.3 35.3
13001 Chatham 435 Grand Ave. W. 8744 0.0 0.2 0.4 1.00 2.7 12.2 1.2 63.7 10.7
14111 Sarnia 700 Christina St. N. 8682 0.6 1.0 1.2 1.70 3.0 14.0 1.9 84.7 11.2
15020 Grand Bend Point Blake Conservation Area 8627 0.0 0.3 0.3 0.40 0.7 2.0 0.4 21.9 1.6
15026 London 42 St. Julien St. 8677 0.0 0.1 0.3 0.60 1.4 13.1 0.9 54.1 12.5
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8247 0.0 0.0 0.1 0.20 0.8 2.5 0.3 13.0 2.6
21005 Brantford 324 Grand River Ave. 8656 0.0 0.1 0.2 0.40 1.5 9.1 0.7 42.7 8.1
26060 Kitchener West Ave./Homewood Ave. 8695 0.1 0.2 0.3 0.50 1.4 13.2 0.9 65.5 16.3
27067 St. Catharines Argyle Cres., Pump Stn. 8697 0.2 0.2 0.4 0.70 1.6 12.2 1.0 87.1 12.5
28028 Guelph Exhibition St./Clark St. W. 8675 0.1 0.2 0.3 0.50 1.4 15.9 1.0 82.6 18.0
29000 Hamilton Downtown Elgin St./Kelly St. 8623 0.6 0.8 1.3 2.40 7.8 35.0 3.5 163.3 45.4
29118 Hamilton West Main St. W./Hwy 403 8679 0.2 0.4 0.9 2.20 7.6 37.1 3.2 113.9 25.2
29214 Hamilton Mountain 250 Fennell Ave. W. 8693 0.2 0.3 0.5 0.90 3.1 14.4 1.4 55.3 14.3
31129 Toronto Downtown 55 John St. 8213 0.5 1.2 2.1 4.20 10.9 39.0 4.8 323.0 36.7
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8677 0.0 0.4 0.9 1.90 4.8 30.5 2.4 121.2 32.3
34021 Toronto North 4905 Dufferin St., ECCC 8527 0.7 0.9 1.2 2.00 4.8 32.2 2.8 108.8 27.0
35125 Toronto West 125 Resources Rd. 8669 0.1 0.8 2.2 5.40 14.3 59.5 6.0 196.7 48.2
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8684 0.0 0.4 0.8 1.70 4.6 22.0 2.1 115.1 25.6
44017 Oakville EightLine/Glenashton Dr., Halton Res. 8545 0.4 0.6 0.8 1.20 2.9 14.2 1.6 109.3 16.0
44029 Milton 1120 Main St. E. 8628 0.3 0.5 0.8 1.50 4.4 36.1 2.6 150.5 26.5
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8723 0.0 0.3 0.5 0.70 1.4 6.6 0.7 31.5 8.2
46090 Brampton 109 McLaughlin Rd. S. 8660 0.0 0.2 0.3 0.70 3.0 26.0 1.5 94.8 23.9
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8384 0.1 0.1 0.3 0.70 3.2 25.5 1.6 86.6 20.7
47045 Barrie 83 Perry St. 8727 0.2 0.4 0.6 0.80 2.1 21.3 1.4 100.3 14.8
48006 Newmarket Eagle St. W./McCaffrey Rd. 8697 0.1 0.3 0.4 0.70 1.5 10.6 0.9 61.3 11.6
49005 Parry Sound 7 Bay St. 8697 0.1 0.2 0.3 0.40 0.8 6.1 0.5 27.7 4.8
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8755 0.4 0.6 0.8 1.10 2.4 14.5 1.5 88.5 15.4
52023 Kingston 23 Beechgrove Lane 8682 0.2 0.3 0.4 0.60 1.3 5.2 0.7 24.1 5.6
54012 Belleville 2 Sidney St., Water Treatment Plant 8622 0.0 0.2 0.4 0.70 2.8 17.1 1.3 65.7 18.1
56051 Cornwall Bedford St./3rd St. W. 8692 0.1 0.3 0.4 0.60 1.5 30.8 1.4 109.0 24.4
59006 Peterborough 10 Hospital Dr. 8692 0.0 0.1 0.2 0.50 1.4 11.3 0.8 49.4 10.0
63203 Thunder Bay 421 James St. S. 8756 0.8 1.0 1.4 2.40 8.3 30.2 3.5 119.0 30.8
71078 Sault Ste. Marie Sault College 8271 0.2 0.3 0.5 1.10 3.1 12.4 1.4 46.6 7.3
75010 North Bay Chippewa St. W., Dept. National Defence 8624 0.4 0.5 0.6 1.00 2.3 18.0 1.5 65.0 14.5
77233 Sudbury 155 Elm St. 8658 0.3 0.5 0.8 1.30 3.4 22.0 1.9 115.4 21.7

 

2021 nitrogen dioxide (NO2) annual statistics

Unit: parts per billion (ppb)
NO2 1h AAQC: 200 ppb
NO2 24h AAQC: 100 ppb

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Max 1h Max 24h Number of times above 1h criteria Number of times above 24h criteria
12008 Windsor Downtown 467 University Ave. W. 8688 3.5 5.3 7.4 10.8 18.6 34.7 9.6 51.0 27.3 0 0
12016 Windsor West College Ave./South St. 8636 2.5 4.2 6.3 9.6 16.9 36.1 8.4 56.6 27.2 0 0
13001 Chatham 435 Grand Ave. W. 8744 1.8 2.8 3.9 5.8 9.7 21.9 5.1 43.8 20.8 0 0
14111 Sarnia 700 Christina St. N. 8682 1.3 2.8 4.8 8.2 15.2 28.7 6.8 50.1 23.5 0 0
15020 Grand Bend Point Blake Conservation Area 8627 0.6 1.2 1.9 2.9 4.8 8.7 2.4 17.4 9.0 0 0
15026 London 42 St. Julien St. 8677 1.8 2.8 4.0 5.8 10.1 22.3 5.2 36.3 17.2 0 0
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8247 0.7 1.2 1.8 2.5 4.2 8.2 2.2 21.3 6.9 0 0
21005 Brantford 324 Grand River Ave. 8656 1.6 2.4 3.4 5.1 9.4 18.6 4.6 37.9 16.8 0 0
26060 Kitchener West Ave./Homewood Ave. 8695 1.2 2.2 3.3 5.2 10.1 25.0 4.8 44.2 19.0 0 0
27067 St. Catharines Argyle Cres., Pump Stn. 8697 2.2 3.2 4.3 6.2 11.1 23.7 5.8 36.4 17.4 0 0
28028 Guelph Exhibition St./Clark St. W. 8675 1.8 2.7 4.0 6.0 10.7 26.0 5.5 39.8 19.4 0 0
29000 Hamilton Downtown Elgin St./Kelly St. 8623 2.9 4.8 7.5 11.9 21.5 39.3 10.2 55.4 40.9 0 0
29118 Hamilton West Main St. W./Hwy 403 8679 3.0 4.9 7.6 11.8 21.0 34.6 10.1 48.5 33.2 0 0
29214 Hamilton Mountain 250 Fennell Ave. W. 8693 0.7 2.1 4.1 7.2 15.3 31.0 6.3 48.7 33.3 0 0
31129 Toronto Downtown 55 John St. 8213 5.0 7.7 10.6 14.7 23.6 38.7 12.7 74.2 37.3 0 0
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8677 3.0 4.9 7.0 10.6 19.5 39.0 9.5 62.8 30.8 0 0
34021 Toronto North 4905 Dufferin St., ECCC 8527 2.7 4.6 6.9 10.7 19.4 37.2 9.3 52.7 31.4 0 0
35125 Toronto West 125 Resources Rd. 8669 3.9 7.2 10.5 15.3 25.7 41.6 12.9 56.7 31.8 0 0
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8684 2.6 4.7 6.9 10.0 17.5 33.1 8.7 50.4 26.8 0 0
44017 Oakville EightLine/Glenashton Dr., Halton Res. 8545 2.1 3.5 5.2 8.1 15.2 30.4 7.3 63.2 30.8 0 0
44029 Milton 1120 Main St. E. 8628 1.9 3.6 5.4 8.7 18.5 38.3 8.2 61.2 32.2 0 0
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8723 0.9 1.5 2.4 3.7 7.2 15.1 3.4 27.0 14.0 0 0
46090 Brampton 109 McLaughlin Rd. S. 8660 1.1 2.3 4.1 7.3 15.2 31.3 6.5 44.8 27.8 0 0
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8384 1.8 3.2 5.0 7.9 15.1 28.9 7.0 42.4 25.3 0 0
47045 Barrie 83 Perry St. 8727 1.6 2.6 3.7 5.7 11.9 29.6 5.6 51.0 24.3 0 0
48006 Newmarket Eagle St. W./McCaffrey Rd. 8697 0.8 1.7 2.8 4.7 9.9 24.9 4.5 42.1 19.3 0 0
49005 Parry Sound 7 Bay St. 8697 0.6 1.1 1.6 2.4 5.1 17.0 2.5 35.4 13.5 0 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8755 1.4 2.4 3.6 6.1 12.7 28.3 5.7 47.6 23.5 0 0
52023 Kingston 23 Beechgrove Lane 8682 1.2 1.8 2.5 3.8 7.7 21.0 3.8 42.6 17.2 0 0
54012 Belleville 2 Sidney St., Water Treatment Plant 8622 0.9 1.6 2.4 3.9 8.2 21.8 3.8 35.0 16.2 0 0
56051 Cornwall Bedford St./3rd St. W. 8692 1.1 1.9 2.8 4.7 10.7 30.5 4.8 52.1 22.2 0 0
59006 Peterborough 10 Hospital Dr. 8692 0.9 1.6 2.6 4.1 8.5 23.7 4.1 42.6 20.2 0 0
63203 Thunder Bay 421 James St. S. 8756 1.6 2.7 4.4 7.2 14.6 30.6 6.5 45.2 26.0 0 0
71078 Sault Ste. Marie Sault College 8271 1.2 1.9 2.7 4.2 8.3 18.4 4.0 50.7 12.4 0 0
75010 North Bay Chippewa St. W., Dept. National Defence 8624 0.8 1.4 2.1 3.6 8.8 27.2 3.9 36.5 19.7 0 0
77233 Sudbury 155 Elm St. 8658 1.4 2.2 3.4 5.6 12.0 34.1 5.6 56.2 24.3 0 0

 

2021 nitrogen oxides (NOx) annual statistics

Unit: parts per billion (ppb)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Max 1h Max 24h
12008 Windsor Downtown 467 University Ave. W. 8688 4.1 6.2 8.6 12.4 21.9 66.6 12.1 259.6 66.7
12016 Windsor West College Ave./South St. 8636 2.8 4.8 7.2 10.9 19.7 69.2 10.7 199.6 59.5
13001 Chatham 435 Grand Ave. W. 8744 1.9 3.1 4.6 6.9 11.9 31.6 6.3 107.5 29.6
14111 Sarnia 700 Christina St. N. 8682 2.2 4.0 6.0 9.9 18.0 40.4 8.7 114.0 28.8
15020 Grand Bend Point Blake Conservation Area 8627 0.8 1.5 2.2 3.3 5.4 9.8 2.8 32.2 9.9
15026 London 42 St. Julien St. 8677 2.0 3.1 4.4 6.5 11.4 30.2 6.1 77.4 25.3
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8247 0.7 1.3 1.9 2.8 4.8 9.8 2.5 31.6 8.9
21005 Brantford 324 Grand River Ave. 8656 1.6 2.6 3.7 5.6 10.8 25.5 5.3 62.0 24.9
26060 Kitchener West Ave./Homewood Ave. 8695 1.5 2.4 3.7 5.8 11.3 35.9 5.7 98.0 29.1
27067 St. Catharines Argyle Cres., Pump Stn. 8697 2.5 3.6 4.9 6.9 12.5 33.3 6.8 105.5 27.4
28028 Guelph Exhibition St./Clark St. W. 8675 2.1 3.1 4.4 6.5 12.1 40.7 6.5 103.8 31.7
29000 Hamilton Downtown Elgin St./Kelly St. 8623 3.8 6.0 9.1 14.6 28.6 67.6 13.7 216.7 86.3
29118 Hamilton West Main St. W./Hwy 403 8679 3.4 5.7 8.9 14.3 28.4 64.7 13.2 141.5 58.3
29214 Hamilton Mountain 250 Fennell Ave. W. 8693 1.1 2.6 4.8 8.4 18.2 41.3 7.7 102.2 47.6
31129 Toronto Downtown 55 John St. 8213 5.9 9.5 13.4 18.9 33.0 73.9 17.4 397.2 66.5
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8677 3.3 5.8 8.2 12.3 23.4 64.77 11.9 168.7 61.0
34021 Toronto North 4905 Dufferin St., ECCC 8527 3.7 5.9 8.5 12.6 23.2 66.34 12.1 147.2 50.7
35125 Toronto West 125 Resources Rd. 8669 4.5 8.7 13.5 20.6 38.5 93.26 18.9 226.4 74.7
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8684 2.9 5.2 7.8 11.7 21.2 51.43 10.7 165.6 51.4
44017 Oakville EightLine/Glenashton Dr., Halton Res. 8545 2.8 4.2 6.2 9.4 17.9 41.6 8.8 150.2 43.9
44029 Milton 1120 Main St. E. 8628 2.5 4.4 6.5 10.2 22.7 67.77 10.8 196.2 58.5
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8723 1.2 2 2.9 4.3 8.3 19.4 4.1 56.9 21.1
46090 Brampton 109 McLaughlin Rd. S. 8660 1.4 2.6 4.5 8.2 18.0 51.98 8.0 132.0 50.0
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8384 2.1 3.5 5.5 8.8 18.1 50.02 8.6 115.7 38.8
47045 Barrie 83 Perry St. 8727 2.1 3.1 4.3 6.5 14.0 46.8 7.0 151.3 36.5
48006 Newmarket Eagle St. W./McCaffrey Rd. 8697 1.2 2.1 3.3 5.4 11.2 34.11 5.4 81.9 26.0
49005 Parry Sound 7 Bay St. 8697 0.8 1.3 1.9 2.8 6.0 20 3.1 58.9 18.3
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8755 2 3.2 4.5 7.3 14.8 40.8 7.2 118.0 35.1
52023 Kingston 23 Beechgrove Lane 8682 1.5 2.2 3 4.4 8.7 25.62 4.5 66.8 22.8
54012 Belleville 2 Sidney St., Water Treatment Plant 8622 1.1 1.9 2.9 4.9 11.1 37.64 5.1 94.2 29.3
56051 Cornwall Bedford St./3rd St. W. 8692 1.4 2.2 3.3 5.2 12.6 53.83 6.2 158.3 39.8
59006 Peterborough 10 Hospital Dr. 8692 1.1 1.9 2.9 4.6 9.9 33.81 4.8 92.0 28.5
63203 Thunder Bay 421 James St. S. 8756 2.6 4 6.2 10.1 22.3 54.15 10.0 155.5 56.7
71078 Sault Ste. Marie Sault College 8271 1.5 2.3 3.4 5.4 11.4 28.23 5.3 97.3 19.7
75010 North Bay Chippewa St. W., Dept. National Defence 8624 1.3 2 2.9 4.7 11.2 42.13 5.4 96.4 31.5
77233 Sudbury 155 Elm St. 8658 1.8 2.9 4.4 6.7 15.5 51.63 7.5 158.5 44.5

 

2021 fine particulate matter (PM2.5) annual statistics

Unit: micrograms per cubic metre (μg/m3)
PM2.5 24h AAQC: 27 μg/m3
PM2.5 Annual AAQC: 8.8 μg/m3

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Max 1h Max 24h Number of times above 24h criteria Number of times above annual criteria
12008 Windsor Downtown 467 University Ave. W. 8730 2 5 7 10 16 29 8.3 54 22.9 0 0
12016 Windsor West College Ave./South St. 8527 3 6 8 12 18 32 9.6 53 27.5 1 1
13001 Chatham 435 Grand Ave. W. 8613 1 3 6 9 14 26 7.1 43 22.8 0 0
14111 Sarnia 700 Christina St. N. 8645 2 3 6 10 16 29 7.7 63 28.4 1 0
15020 Grand Bend Point Blake Conservation Area 8720 2 3 5 7 11 21 5.7 43 23.0 0 0
15026 London 42 St. Julien St. 8742 2 4 7 10 15 26 7.8 43 27.0 0 0
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8522 2 4 6 8 14 25 7.0 66 27.5 1 0
18007 Tiverton 4th Concession/Bruce Rd. 23 8075 1 2 4 7 11 22 5.4 41 23.6 0 0
21005 Brantford 324 Grand River Ave. 8693 2 4 6 9 15 26 7.7 51 30.0 2 0
26060 Kitchener West Ave./Homewood Ave. 8535 1 3 6 10 17 32 7.8 57 35.8 1 0
27067 St. Catharines Argyle Cres., Pump Stn. 8552 2 3 5 8 13 24 6.5 46 25.5 0 0
28028 Guelph Exhibition St./Clark St. W. 8669 2 3 6 9 16 30 7.7 69 34.5 2 0
29000 Hamilton Downtown Elgin St./Kelly St. 8589 2 4 7 11 18 32 8.9 86 34.4 4 1
29118 Hamilton West Main St. W./Hwy 403 8624 2 4 6 9 16 30 8.0 63 32.7 2 0
29214 Hamilton Mountain 250 Fennell Ave. W. 8672 2 4 7 10 16 29 8.0 62 30.2 1 0
31129 Toronto Downtown 55 John St. 8699 3 5 7 10 16 32 8.4 170 58.7 3 0
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8674 2 4 6 9 14 30 7.4 70 35.1 4 0
34021 Toronto North 4905 Dufferin St., ECCC 8611 2 4 6 9 14 31 7.4 69 30.2 2 0
35125 Toronto West 125 Resources Rd. 8651 2 4 6 9 14 31 7.7 93 43.2 2 0
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8751 2 3 6 9 14 29 7.2 60 26.6 0 0
44017 Oakville EightLine/Glenashton Dr., Halton Res. 8718 2 4 6 8 14 27 7.1 76 33.9 1 0
44029 Milton 1120 Main St. E. 8678 2 4 6 9 15 30 7.6 89 29.3 1 0
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8716 2 3 5 7 12 27 6.2 78 32.2 1 0
46090 Brampton 109 McLaughlin Rd. S. 8688 2 4 6 8 14 29 7.2 92 33.4 1 0
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8373 1 3 6 10 16 30 7.6 77 40.1 1 0
47045 Barrie 83 Perry St. 8447 2 3 5 8 13 30 6.9 129 45.5 2 0
48006 Newmarket Eagle St. W./McCaffrey Rd. 8751 2 3 5 8 13 26 6.5 65 30.1 2 0
49005 Parry Sound 7 Bay St. 8750 1 2 4 6 11 21 5.0 49 27.7 1 0
49010 Dorset 1026 Bellwood Acres Rd. 8720 1 2 3 6 11 22 4.7 78 37.1 1 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8657 2 3 5 7 12 24 6.3 54 33.7 2 0
51010 Petawawa Petawawa Research Forest Facility 8620 2 2 3 5 8 20 4.3 41 30.2 1 0
52023 Kingston 23 Beechgrove Lane 8701 1 3 5 8 13 27 6.5 74 35.1 3 0
54012 Belleville 2 Sidney St., Water Treatment Plant 8549 2 3 5 7 11 23 6.0 65 37.7 2 0
56051 Cornwall Bedford St./3rd St. W. 8570 2 3 5 7 13 30 6.5 66 32.6 2 0
59006 Peterborough 10 Hospital Dr. 8738 1 2 4 8 15 31 6.5 67 28.6 1 0
63203 Thunder Bay 421 James St. S. 8736 2 3 5 7 12 41 6.6 127 52.2 7 0
71078 Sault Ste. Marie Sault College 8698 2 3 4 6 11 31 5.8 101 44.8 4 0
75010 North Bay Chippewa St. W., Dept. National Defence 8743 2 3 4 6 11 25 5.7 91 37.0 2 0
77233 Sudbury 155 Elm St. 8694 2 3 4 6 11 28 5.8 163 48.8 3 0

Notes

  • Measurements taken by SHARP 5030.
  • The PM2.5 AAQC values, based on the 24-hour PM2.5 Canadian Ambient Air Quality Standard (CAAQS), are used "as is" for comparison to an average concentration in a year.

2021 ground-level ozone (O3) annual statistics

Unit: parts per billion (ppb)
O3 1h AAQC: 80 ppb

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Max 1h Max 24h Number of times above 1h criterion
12008 Windsor Downtown 467 University Ave. W. 8689 13 22 28 35 46 64 28.8 82 56.13 2
12016 Windsor West College Ave./South St. 8680 13 23 29 35 46 64 29.4 86 57 2
13001 Chatham 435 Grand Ave. W. 8745 17 24 30 35 46 62 30.4 75 59.92 0
14111 Sarnia 700 Christina St. N. 8445 15 23 28 36 47 68 30.2 97 57.79 6
15020 Grand Bend Point Blake Conservation Area 8618 17 26 32 37 45 66 32.0 104 62.13 18
15026 London 42 St. Julien St. 8675 11 22 29 35 45 61 28.9 78 59.83 0
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8688 18 25 31 36 46 63 31.4 74 58.67 0
18007 Tiverton 4th Concession/Bruce Rd. 23 8593 19 27 32 37 45 64 32.4 78 64.5 0
21005 Brantford 324 Grand River Ave. 8660 11 22 29 35 45 62 28.5 79 61.21 0
26060 Kitchener West Ave./Homewood Ave. 8693 14 23 28 34 42 60 28.4 81 58.33 1
27067 St. Catharines Argyle Cres., Pump Stn. 8645 13 24 30 36 45 62 29.8 73 61.71 0
28028 Guelph Exhibition St./Clark St. W. 8676 13 23 30 35 44 63 29.5 83 61.08 4
29000 Hamilton Downtown Elgin St./Kelly St. 8623 10 19 26 32 43 60 26.4 80 61.92 0
29118 Hamilton West Main St. W./Hwy 403 8683 6 18 25 31 41 58 24.9 78 59.79 0
29214 Hamilton Mountain 250 Fennell Ave. W. 8694 13 22 28 34 44 61 28.7 80 62.54 0
31129 Toronto Downtown 55 John St. 8753 11 20 26 31 41 61 26.3 86 57.5 4
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8677 10 20 26 32 41 60 26.2 78 55.08 0
34021 Toronto North 4905 Dufferin St., ECCC 8466 9 19 26 32 43 64 26.4 86 61.39 3
35125 Toronto West 125 Resources Rd. 8667 5 15 22 29 39 61 22.8 81 56.13 1
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8681 11 21 27 34 43 60 27.4 80 59.38 0
44017 Oakville EightLine/Glenashton Dr., Halton Res. 8700 13 22 29 34 44 63 28.8 84 61.83 2
44029 Milton 1120 Main St. E. 8663 9 21 28 34 43 63 27.2 84 61.54 3
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8704 9 21 28 33 42 62 26.9 80 47.58 0
46090 Brampton 109 McLaughlin Rd. S. 8670 11 22 29 35 44 64 28.3 84 61.33 3
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8390 8 19 27 33 42 61 26.2 81 60.75 1
47045 Barrie 83 Perry St. 8727 9 19 25 31 39 55 25.0 82 50.21 1
48006 Newmarket Eagle St. W./McCaffrey Rd. 8692 15 24 30 36 44 63 30.2 81 61.58 1
49005 Parry Sound 7 Bay St. 8700 17 25 30 35 44 61 30.3 80 58.29 0
49010 Dorset 1026 Bellwood Acres Rd. 8741 9 21 28 34 42 59 26.8 70 47.64 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8756 11 20 26 32 40 56 25.8 68 51.21 0
51010 Petawawa Petawawa Research Forest Facility 8710 11 20 27 33 41 55 26.7 66 52.33 0
52023 Kingston 23 Beechgrove Lane 8692 15 24 30 36 44 62 30.2 78 62.5 0
54012 Belleville 2 Sidney St., Water Treatment Plant 8627 14 24 30 36 46 65 30.3 82 64.29 1
56051 Cornwall Bedford St./3rd St. W. 8696 11 21 27 33 42 57 26.7 70 58.25 0
59006 Peterborough 10 Hospital Dr. 8670 13 22 28 35 43 61 28.6 85 57.35 1
63203 Thunder Bay 421 James St. S. 8759 8 19 25 31 39 50 24.4 65 49.88 0
71078 Sault Ste. Marie Sault College 8725 16 24 29 34 42 56 29.2 66 52.46 0
75010 North Bay Chippewa St. W., Dept. National Defence 8411 10 21 27 32 41 58 26.4 71 54.08 0
77233 Sudbury 155 Elm St. 8635 12 19 24 29 36 47 23.9 56 45.17 0

 

2021 sulphur dioxide (SO2) annual statistics

Unit: parts per billion (ppb)
SO2 10 min AAQC: 67 ppb
SO2 1h AAQC: 40 ppb
SO2 1y AAQC: 4 ppb

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Max 10 min Max 1h Max 24h Number of times above 10 min criteria Number of times above 1h criteria Number of times above annual criteria
12008 Windsor Downtown 467 University Ave. W. 8553 0.0 0.0 0.1 0.2 0.9 5.10 0.38 27.6 20.2 3.9 0 0 0
12016 Windsor West College Ave./South St. 8689 0.0 0.1 0.2 0.5 1.6 7.21 0.66 28.7 22.8 5.9 0 0 0
14111 Sarnia 700 Christina St. N. 8567 0.1 0.2 0.3 0.6 4.6 37.77 2.23 133.4 84.2 31.6 85 66 0
29000 Hamilton Downtown Elgin St./Kelly St. 8620 0.0 0.2 0.4 1.2 11.6 49.76 3.82 169.8 108.5 30.8 219 169 0
29214 Hamilton Mountain 250 Fennell Ave. W. 8691 0.0 0.2 0.5 1.2 10.1 37.01 3.16 163.3 117.6 33.6 51 60 0
34021 Toronto North 4905 Dufferin St., ECCC 8485 0.0 0.0 0.0 0.1 0.4 2.30 0.17 15.4 9.2 2.0 0 0 0
35125 Toronto West 125 Resources Rd. 8671 0.0 0.0 0.1 0.2 0.5 2.70 0.24 22.2 11.8 2.1 0 0 0
44029 Milton 1120 Main St. E. 5327 0.4 0.6 0.8 1.2 1.6 4.10 INS 23.5 9.5 2.5 0 0 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8652 0.0 0.1 0.1 0.2 0.3 0.70 0.16 18.5 4.6 0.7 0 0 0
71078 Sault Ste. Marie Sault College 8700 0.3 0.4 0.4 0.5 0.9 10.10 0.83 61.8 40.4 6.5 0 1 0
77233 Sudbury 155 Elm St. 8679 0.0 0.1 0.2 0.3 1.3 14.14 0.85 208.6 77.9 13.9 16 5 0

 

2021 carbon monoxide (CO) annual statistics

Unit: parts per million (ppm)
CO 1h AAQC: 30 ppm
CO 8h AAQC: 13 ppm

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Max 1h Max 8h Number of times above 1h criteria Number of times above 8h criteria
12008 Windsor Downtown 467 University Ave. W. 8503 0.16 0.19 0.22 0.25 0.32 0.58 0.24 1.57 1.00 0 0
29000 Hamilton Downtown Elgin St./Kelly St. 8563 0.15 0.17 0.20 0.24 0.36 0.62 0.23 1.45 0.80 0 0
34021 Toronto North 4905 Dufferin St., ECCC 8540 0.15 0.17 0.20 0.23 0.29 0.52 0.21 2.11 0.94 0 0
35125 Toronto West 125 Resources Rd. 8588 0.16 0.19 0.22 0.26 0.35 0.64 0.24 1.18 0.95 0 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 3297 0.14 0.16 0.19 0.22 0.28 0.45 INS 0.77 0.52 0 0

 

2021 total reduced sulphur (TRS) compounds annual statistics

Unit: parts per billion (ppb)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Max 1h Max 24h
12016 Windsor West College Ave./South St. 8177 0 0 0 0 0 3 0.14 11 2.8
14111 Sarnia 700 Christina St. N. 7859 0 0 0 0 0 1 0.02 2 0.7
29000 Hamilton Downtown Elgin St./Kelly St. 8619 0 0 0 0 0 1 0.03 3 0.6
71078 Sault Ste. Marie Sault College 8656 0 0 0 0 1 1 0.24 3 1.1

 

2021 benzene annual statistics

Unit: micrograms per cubic metre (μg/m3)
Benzene 24h AAQC: 2.3 μg/m3
Benzene Annual AAQC: 0.45 μg/m3

ID City Number of samples 10% 25% 50% 75% 90% Max Min Mean Standard deviation Number of times above 24h criteria Number of times above annual criteria
12016 Windsor West 41 0.267 0.332 0.419 0.570 0.703 2.029 0.188 0.527 0.389 0 1
14111 Sarnia 53 0.188 0.299 0.417 0.686 1.293 1.966 0.073 0.570 0.448 0 1
15026 London N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
26060 Kitchener N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
29000 Hamilton Downtown 41 0.238 0.279 0.425 0.590 1.425 3.122 0.141 0.613 0.629 2 1
48006 Newmarket N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

 

2021 toluene annual statistics

Unit: micrograms per cubic metre (μg/m3)
Toluene 24h AAQC (based on odour): 2,000 μg/m

ID City Number of samples 10% 25% 50% 75% 90% Max Min Mean Standard deviation Number of times above 24h criteria
12016 Windsor West 41 0.362 0.485 0.830 1.415 2.353 2.854 0.188 1.085 0.758 0
14111 Sarnia 53 0.174 0.358 0.696 1.440 2.534 4.574 0.120 1.053 1.004 0
15026 London N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
26060 Kitchener N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
29000 Hamilton Downtown 41 0.302 0.408 0.706 1.311 1.795 18.517 0.151 1.314 2.822 0
48006 Newmarket N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

 

2021 ethylbenzene annual statistics

Unit: micrograms per cubic metre (μg/m3)
Ethylbenzene 24h AAQC: 1,000 μg/m3

ID City Number of samples 10% 25% 50% 75% 90% Max Min Mean Standard deviation Number of times above 24h criteria
12016 Windsor West 41 0.072 0.084 0.154 0.277 0.341 3.299 0.035 0.328 0.691 0
14111 Sarnia 53 0.035 0.035 0.103 0.205 0.402 1.743 0.035 0.187 0.271 0
15026 London N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
26060 Kitchener N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
29000 Hamilton Downtown 41 0.035 0.035 0.115 0.189 0.238 2.133 0.035 0.172 0.326 0
48006 Newmarket N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

 

2021 m- and p-xylene annual statistics

Unit: micrograms per cubic metre (μg/m3)

ID City Number of samples 10% 25% 50% 75% 90% Max Min Mean Standard deviation
12016 Windsor West 41 0.172 0.239 0.457 0.855 1.159 2.310 0.128 0.619 0.531
14111 Sarnia 53 0.067 0.121 0.228 0.498 0.694 1.377 0.035 0.319 0.269
15026 London N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
26060 Kitchener N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
29000 Hamilton Downtown 41 0.132 0.188 0.310 0.554 0.740 4.793 0.041 0.486 0.744
48006 Newmarket N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

 

2021 o-xylene annual statistics

Unit: micrograms per cubic metre (μg/m3)

ID City Number of samples 10% 25% 50% 75% 90% Max Min Mean Standard deviation
12016 Windsor West 41 0.040 0.112 0.189 0.346 0.433 0.939 0.040 0.246 0.208
14111 Sarnia 53 0.040 0.040 0.095 0.171 0.256 0.431 0.040 0.122 0.095
15026 London N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
26060 Kitchener N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
29000 Hamilton Downtown 41 0.040 0.040 0.107 0.211 0.272 2.136 0.040 0.183 0.331
48006 Newmarket N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

 

2021 1,3-butadiene annual statistics

Unit: micrograms per cubic metre (μg/m3)
1,3-Butadiene 24h AAQC: 10.0 μg/m3
1,3-Butadiene Annual AAQC: 2.0 μg/m3

ID City Number of samples 10% 25% 50% 75% 90% Max Min Mean Standard deviation Number of times above 24h criteria Number of times above annual criteria
12016 Windsor West 41 0.035 0.035 0.035 0.035 0.035 0.097 0.035 0.038 0.012 0 0
14111 Sarnia 53 0.035 0.035 0.035 0.035 0.104 0.641 0.035 0.071 0.108 0 0
15026 London N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
26060 Kitchener N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
29000 Hamilton Downtown 41 0.035 0.035 0.035 0.035 0.035 0.087 0.035 0.036 0.008 0 0
48006 Newmarket N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

10-year trends

10-year trend for nitric oxide (NO)

Annual mean (ppb)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 4.7 3.7 4.0 3.5 3.1 3.3 3.2 2.7 1.7 2.5 -33.4 SSS
12016 Windsor West 4.6 3.6 3.8 4.2 2.9 2.6 2.6 3.1 1.7 2.3 -34.8 SSS
13001 Chatham 1.8 1.6 1.5 1.7 1.4 1.9 1.8 1.4 1.5 1.2 -5.1 Non-SSS
14111 Sarnia 2.1 1.7 1.9 2.4 INS 1.5 1.8 1.7 1.6 1.9 -6.1 SSS
15020 Grand Bend 0.3 1.0 0.2 0.3 0.5 0.3 0.2 0.3 0.4 0.4 23.1 Non-SSS
15026 London 4.2 1.4 1.3 1.4 1.0 1.0 0.8 0.9 0.7 0.9 -22.1 SSS
21005 Brantford 1.1 1.2 0.9 1.3 0.8 0.8 1.0 0.9 0.8 0.7 -15.0 SSS
26060 Kitchener 2.1 1.6 1.6 1.6 1.3 1.0 0.9 1.2 0.7 0.9 -20.1 SSS
27067 St. Catharines 2.5 2.2 1.7 2.1 1.5 1.2 0.9 1.2 0.9 1.0 -42.8 SSS
28028 Guelph 2.2 1.1 1.2 1.3 1.1 1.1 1.2 0.9 0.8 1.0 -20.1 SSS
29000 Hamilton Downtown 4.6 4.3 3.9 1.3 4.2 3.9 3.9 4.0 2.9 3.5 -17.5 SSS
29118 Hamilton West 6.3 5.4 5.9 5.1 6.2 3.9 4.2 4.2 3.2 3.2 -43.8 SSS
29214 Hamilton Mountain 1.9 2.0 2.0 1.8 1.2 1.2 1.2 1.8 1.4 1.4 -22.0 SSS
33003 Toronto East 6.6 5.7 6.2 5.8 5.4 4.4 3.1 3.4 2.3 2.4 -61.0 SSS
34021 Toronto North 5.0 4.1 4.3 3.9 3.5 3.0 2.5 2.7 2.1 2.8 -41.8 SSS
35125 Toronto West 11.3 8.6 9.5 9.2 8.2 7.7 6.7 7.5 5.2 6.0 -38.4 SSS
44008 Burlington 4.6 4.6 4.6 3.9 3.9 3.4 2.7 3.0 2.3 2.1 -50.4 SSS
44017 Oakville 3.4 2.1 3.4 2.7 1.8 1.7 1.8 1.8 1.3 1.6 -26.3 SSS
44029 Milton 4.8 2.8 3.1 3.5 4.2 2.3 3.6 3.6 2.7 2.6 -7.4 SSS
45027 Oshawa 2.1 1.5 2.0 2.3 2.5 2.4 0.9 0.9 0.9 0.7 -43.2 SSS
46090 Brampton 4.4 4.6 4.0 3.8 3.4 2.2 2.2 2.2 1.4 1.5 -49.3 SSS
46108 Mississauga 3.8 3.1 2.9 3.1 3.6 2.0 1.6 2.6 1.4 1.6 -36.8 SSS
47045 Barrie 3.2 3.2 3.7 3.5 3.7 2.6 1.8 2.2 1.4 1.4 -69.1 SSS
48006 Newmarket 2.0 1.5 1.4 1.7 1.6 1.4 1.3 1.3 0.8 0.9 -42.9 SSS
49005 Parry Sound 0.5 0.5 0.6 0.8 0.6 0.5 0.5 0.7 0.4 0.5 0.0 Non-SSS
51001 Ottawa Downtown 2.4 2.1 1.9 2.0 1.7 1.5 1.7 1.6 1.4 1.5 -16.2 SSS
52023 Kingston 0.4 0.2 0.8 0.9 0.7 0.6 0.6 0.6 0.7 0.7 32.9 SSS
54012 Belleville 1.6 1.7 1.2 1.5 1.8 1.1 1.0 1.3 1.4 1.3 -7.6 Non-SSS
56051 Cornwall 2.2 1.9 1.5 1.8 2.1 1.2 1.4 1.5 1.2 1.4 -8.1 SSS
59006 Peterborough 1.8 1.7 1.8 1.5 1.3 1.2 0.9 1.2 1.0 0.8 -51.1 SSS
63203 Thunder Bay 5.1 4.7 4.2 5.2 3.8 4.1 3.8 3.8 3.4 3.5 -20.7 SSS
71078 Sault Ste. Marie 1.7 1.3 2.0 1.7 1.0 1.3 1.2 1.5 1.6 1.4 -16.3 SSS
75010 North Bay 2.9 2.5 2.6 2.1 2.0 1.6 1.7 1.8 1.4 1.5 -41.9 SSS
77233 Sudbury N/A 2.9 3.3 2.9 3.3 2.5 2.3 2.8 2.4 1.9 -12.8 SSS

Notes:

  • N/A indicates data not available.
  • INS indicates there was insufficient data to calculate a valid annual mean.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • Station 15026 replaced station 15025 as the London site in 2013.
  • Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
  • Station 34021 replaced station 34020 as the Toronto North site in 2017.
  • Station 44029 was operated by the Halton Region prior to 2019.
  • Station 45027 replaced station 45026 as the Oshawa site in 2018.
  • Station 46090 replaced station 46089 as the Brampton site in 2017.
  • Station 52023 replaced station 52022 as the Kingston site in 2014.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for nitrogen dioxide (NO2)

Annual mean (ppb)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 13.2 12.4 14.0 12.7 11.4 11.1 11.0 10.9 9.0 9.6 -28.6 SSS
12016 Windsor West 11.4 11.5 11.8 11.4 10.6 9.9 8.8 10.0 8.1 8.4 -33.3 SSS
13001 Chatham 5.7 6.0 6.8 6.8 5.4 6.1 5.1 5.8 5.1 5.1 -19.5 SSS
14111 Sarnia 8.6 8.1 9.0 9.3 INS 7.3 7.6 6.8 5.9 6.8 -25.0 SSS
15020 Grand Bend 3.6 4.4 3.1 3.4 2.8 3.0 3.3 2.5 2.3 2.4 -37.7 SSS
15026 London 6.3 6.4 6.9 6.6 5.4 5.8 5.4 5.8 4.5 5.2 -27.8 SSS
21005 Brantford 5.4 4.8 5.5 5.5 4.8 4.4 5.2 5.6 4.3 4.6 -10.9 SSS
26060 Kitchener 7.1 6.7 7.0 6.8 6.2 5.8 5.8 6.3 4.9 4.8 -27.1 SSS
27067 St. Catharines 8.1 7.7 7.3 7.3 6.6 6.6 6.0 6.0 5.3 5.8 -32.0 SSS
28028 Guelph 6.5 6.6 7.1 6.3 6.2 5.9 5.9 5.4 4.9 5.5 -25.5 SSS
29000 Hamilton Downtown 11.9 12.4 12.4 12.2 11.9 11.9 11.6 12.5 9.9 10.2 -17.2 SSS
29118 Hamilton West 12.1 12.7 12.8 12.2 11.8 10.4 11.0 11.3 9.5 10.1 -25.1 SSS
29214 Hamilton Mountain 8.6 9.0 9.3 9.0 7.9 7.8 7.8 8.8 6.9 6.3 -27.0 SSS
33003 Toronto East 14.0 13.6 14.2 13.9 12.1 11.5 10.6 10.2 8.4 9.5 -41.6 SSS
34021 Toronto North 13.4 12.9 13.4 12.9 12.0 10.5 10.4 10.5 8.9 9.3 -36.5 SSS
35125 Toronto West 16.3 16.1 17.1 16.6 15.7 15.0 14.4 14.6 12.1 12.9 -26.7 SSS
44008 Burlington 11.0 11.0 10.9 10.4 10.2 9.7 9.4 9.6 8.2 8.7 -24.4 SSS
44017 Oakville 9.1 9.2 8.2 7.5 8.2 8.2 8.5 9.1 6.8 7.3 -17.7 SSS
44029 Milton 10.4 8.5 8.4 9.4 9.3 7.7 9.8 8.9 7.6 8.2 -11.2 SSS
45027 Oshawa 5.6 5.9 6.8 6.6 6.3 6.4 3.8 3.5 3.6 3.4 -50.2 SSS
46090 Brampton 10.4 9.1 10.6 9.9 9.7 8.3 8.1 8.6 6.8 6.5 -35.0 SSS
46108 Mississauga 9.6 9.5 9.2 9.2 8.6 8.0 7.2 8.4 6.7 7.0 -29.9 SSS
47045 Barrie 8.1 7.8 8.1 7.4 8.1 7.3 6.4 6.3 5.6 5.6 -31.2 SSS
48006 Newmarket 7.2 6.8 6.8 6.8 6.5 6.3 6.1 5.5 4.5 4.5 -37.7 SSS
49005 Parry Sound 3.3 2.9 3.3 3.2 2.9 2.7 2.9 2.6 2.4 2.5 -25.3 SSS
51001 Ottawa Downtown 7.8 7.9 7.4 7.4 6.9 7.1 7.3 6.7 5.9 5.7 -24.9 SSS
52023 Kingston 4.0 3.6 3.9 4.4 4.4 4.4 4.2 4.0 3.5 3.8 -11.2 SSS
54012 Belleville 4.7 4.7 4.5 4.8 5.1 4.3 3.7 4.2 3.5 3.8 -20.6 SSS
56051 Cornwall 6.1 6.2 5.6 5.3 5.5 5.0 5.1 5.0 4.6 4.8 -15.1 SSS
59006 Peterborough 3.7 5.0 5.3 5.1 4.5 4.7 4.5 3.9 4.1 4.1 -32.6 SSS
63203 Thunder Bay 7.3 7.3 7.8 7.5 7.1 6.7 7.5 6.7 6.1 6.5 -15.5 SSS
71078 Sault Ste. Marie 4.8 5.0 5.3 4.8 4.0 4.4 4.4 4.5 3.7 4.0 -25.0 SSS
75010 North Bay 6.1 5.8 5.6 5.6 4.7 4.6 4.9 5.1 4.3 3.9 -26.5 SSS
77233 Sudbury N/A 7.2 7.3 7.2 7.0 6.8 6.5 6.9 6.3 5.6 -8.2 SSS

Notes:

  • N/A indicates data not available.
  • INS indicates there was insufficient data to calculate a valid annual mean.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • Station 15026 replaced station 15025 as the London site in 2013.
  • Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
  • Station 34021 replaced station 34020 as the Toronto North site in 2017.
  • Station 44029 was operated by the Halton Region prior to 2019.
  • Station 45027 replaced station 45026 as the Oshawa site in 2018.
  • Station 46090 replaced station 46089 as the Brampton site in 2017.
  • Station 52023 replaced station 52022 as the Kingston site in 2014.
  • SSS - Significant Sen's Slope (significant trend detected).

10-year trend for nitrogen oxides (NOx)

Annual mean (ppb)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 17.8 16.2 18.0 16.2 14.5 14.4 14.2 13.6 10.7 12.1 -29.5 SSS
12016 Windsor West 16.0 15.2 15.7 15.5 13.5 12.5 11.3 13.0 9.9 10.7 -34.2 SSS
13001 Chatham 7.5 7.7 8.2 8.5 6.8 8.0 6.9 7.2 6.6 6.3 -17.4 SSS
14111 Sarnia 10.7 9.8 10.9 11.7 INS 8.7 9.4 8.5 7.5 8.7 -20.5 SSS
15020 Grand Bend 3.9 5.4 3.4 3.8 3.3 3.4 3.4 2.7 2.7 2.8 -34.0 SSS
15026 London 10.5 7.8 8.3 8.0 6.5 6.8 6.2 6.6 5.2 6.1 -31.0 SSS
21005 Brantford 6.7 5.7 6.4 6.8 5.7 5.3 6.2 6.5 5.1 5.3 -11.8 SSS
26060 Kitchener 9.2 8.3 8.5 8.4 7.5 6.9 6.7 7.4 5.5 5.7 -26.3 SSS
27067 St. Catharines 10.6 9.9 9.1 9.4 8.2 7.9 6.8 7.1 6.2 6.8 -34.8 SSS
28028 Guleph 8.8 7.8 8.4 7.7 7.3 7.0 7.1 6.4 5.6 6.5 -26.4 SSS
29000 Hamilton Downtown 16.6 16.8 16.3 7.7 16.1 15.8 15.5 16.5 12.8 13.7 -18.3 SSS
29118 Hamilton West 18.4 18.1 18.7 17.3 17.9 14.2 15.2 16.5 12.6 13.2 -33.2 SSS
29214 Hamilton Mountain 10.5 11.0 11.3 10.9 9.2 9.1 8.9 15.4 8.3 7.7 -27.0 SSS
33003 Toronto East 20.6 19.4 20.4 19.7 17.5 15.8 13.7 13.7 10.7 11.9 -49.6 SSS
34021 Toronto North 18.5 17.0 17.7 16.9 15.4 13.5 12.8 13.2 11.0 12.1 -40.2 SSS
35125 Toronto West 27.6 24.7 26.5 25.7 23.8 22.7 21.1 22.1 17.2 18.9 -32.8 SSS
44008 Burlington 15.6 15.6 15.5 14.3 14.2 13.2 12.0 12.6 10.5 10.7 -32.6 SSS
44017 Oakville 12.6 11.2 11.6 10.1 10.1 9.9 10.4 10.9 8.0 8.8 -24.4 SSS
44029 Milton 15.3 11.8 12.0 13.2 13.5 10.0 13.4 12.5 10.3 10.8 -13.0 SSS
45027 Oshawa 7.8 7.4 8.8 8.9 8.8 8.8 4.7 4.4 4.5 4.1 -48.8 SSS
46090 Brampton 14.8 13.9 14.6 13.7 13.1 10.6 10.3 10.74 8.1 8.0 -44.1 SSS
46108 Mississauga 13.4 12.6 12.1 12.3 12.2 9.9 8.8 10.97 8.0 8.6 -33.6 SSS
47045 Barrie 11.3 11.0 11.8 10.9 11.9 9.9 8.3 8.52 6.9 7.0 -42.4 SSS
48006 Newmarket 9.2 8.4 8.2 8.5 8.1 7.8 7.4 6.78 5.2 5.4 -37.2 SSS
49005 Parry Sound 3.8 3.4 4.0 4.0 3.6 3.3 3.3 3.34 2.8 3.1 -23.4 SSS
51001 Ottawa Downtown 10.2 10.1 9.3 9.5 8.6 8.6 9.0 8.31 7.3 7.2 -24.4 SSS
52023 Kingston 4.6 3.8 4.8 5.3 5.2 4.9 4.7 4.55 4.1 4.5 -10.8 SSS
54012 Belleville 6.4 6.3 5.7 6.2 6.7 5.4 4.7 5.53 4.9 5.1 -18.9 SSS
56051 Cornwall 8.4 8.0 7.0 7.1 7.6 6.2 6.3 6.54 5.8 6.2 -14.9 SSS
59006 Peterborough 5.4 6.6 7.1 6.6 5.9 5.8 5.3 5.14 5.0 4.8 -36.5 SSS
63203 Thunder Bay 12.4 12.0 11.9 12.7 11 10.8 11.3 10.44 9.5 10.0 -18.7 SSS
71078 Sault Ste. Marie 6.4 6.3 7.3 6.6 5.1 5.8 5.6 5.95 5.2 5.3 -22.9 SSS
75010 North Bay 9.1 8.3 8.1 7.8 6.7 6.2 6.6 6.91 5.6 5.4 -31.6 SSS
77233 Sudbury N/A 10.1 10.6 10.2 10.2 9.4 8.8 9.7 8.7 7.5 -12.1 SSS

Notes:

  • N/A indicates data not available.
  • INS indicates there was insufficient data to calculate a valid annual mean.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • Station 15026 replaced station 15025 as the London site in 2013.
  • Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
  • Station 34021 replaced station 34020 as the Toronto North site in 2017.
  • Station 44029 was operated by the Halton Region prior to 2019.
  • Station 45027 replaced station 45026 as the Oshawa site in 2018.
  • Station 46090 replaced station 46089 as the Brampton site in 2017.
  • Station 52023 replaced station 52022 as the Kingston site in 2014.
  • SSS - Significant Sen's Slope (significant trend detected).

10-year trend for fine particulate matter (PM2.5)

Annual mean (µg/m3)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 9.8 9.2 10.1 9.3 8.1 7.8 8.5 7.8 7.1 8.3 -22.5 SSS
12016 Windsor West 9.5 10.0 10.7 9.9 8.5 8.5 8.7 9.1 8.8 9.6 -8.8 SSS
13001 Chatham 7.5 8.1 8.6 8.1 6.6 6.4 6.8 6.8 6.7 7.1 -16.1 SSS
14111 Sarnia 12.7 8.5 9.0 8.4 INS 7.0 7.4 7.1 7.1 7.7 -32.1 SSS
15020 Grand Bend 7.4 7.3 8.1 7.7 6.0 5.1 5.6 5.4 4.8 5.7 -35.3 SSS
15026 London 8.1 9.1 8.8 8.3 7.1 7.0 7.3 6.7 6.5 7.8 -22.7 SSS
16015 Port Stanley 7.4 7.4 8.2 8.0 6.5 6.3 6.8 6.7 6.5 7.0 -16.2 SSS
18007 Tiverton 6.0 5.8 6.5 6.4 5.1 5.1 5.7 5.0 4.8 5.4 -18.2 SSS
21005 Brantford 7.8 8.5 9.2 8.7 7.3 7.2 7.7 7.4 6.7 7.7 -17.1 SSS
26060 Kitchener 7.7 8.7 9.3 8.8 7.3 7.0 7.4 7.2 6.6 7.8 -19.6 SSS
27067 St. Catharines 7.9 8.5 8.8 8.4 6.9 7.0 7.0 7.0 6.3 6.5 -25.6 SSS
28028 Guelph 7.4 8.1 8.9 8.4 6.9 6.8 7.4 7.1 6.9 7.7 -11.4 SSS
29000 Hamilton Downtown 10.2 10.1 10.8 10.2 8.2 8.5 9.2 8.8 8.1 8.9 -20.9 SSS
29118 Hamilton West 9.0 9.6 9.9 9.9 7.9 7.5 8.2 7.8 7.8 8.0 -18.6 SSS
29214 Hamilton Mountain 8.1 9.2 9.4 9.0 7.2 7.4 7.7 7.9 7.1 8.0 -20.0 SSS
33003 Toronto East 7.8 8.2 8.9 8.5 7.0 7.4 7.2 7.0 6.7 7.4 -16.1 SSS
34021 Toronto North 9.0 8.3 9.2 9.4 7.3 7.4 7.6 6.8 6.4 7.4 -27.2 SSS
35125 Toronto West 8.8 8.8 9.1 8.5 7.0 7.4 7.7 7.2 6.9 7.7 -21.2 SSS
44008 Burlington 8.0 8.7 9.6 9.4 7.6 7.0 7.2 7.0 6.4 7.2 -27.4 SSS
44017 Oakville 7.6 8.0 8.5 8.3 7.0 6.9 7.4 7.2 6.3 7.1 -17.3 SSS
44029 Milton 7.9 8.5 10.3 8.8 7.1 7.0 7.5 7.5 7.1 7.6 -16.3 SSS
45027 Oshawa 6.9 7.4 7.7 7.5 5.9 5.9 6.4 6.1 6.2 6.2 -19.4 SSS
46090 Brampton 7.2 8.5 8.9 8.4 6.8 7.0 7.3 6.8 6.7 7.2 -16.5 SSS
46108 Mississauga 7.5 7.9 8.7 8.5 7.2 6.8 7.3 7.0 6.6 7.6 -15.1 SSS
47045 Barrie 7.1 7.5 7.6 7.6 6.5 7.0 7.7 7.5 6.8 6.9 -5.9 Non-SSS
48006 Newmarket 7.1 7.3 7.3 7.1 6.0 5.9 6.4 5.9 5.9 6.5 -18.4 SSS
49005 Parry Sound 6.0 5.8 5.8 5.7 4.8 4.6 5.0 4.4 4.4 5.0 -31.0 SSS
49010 Dorset 5.3 5.4 5.3 5.6 4.6 4.6 4.9 4.1 4.5 4.7 -16.8 SSS
51001 Ottawa Downtown 6.2 7.0 7.0 6.9 5.9 5.9 5.9 5.9 6.0 6.3 -13.5 SSS
51010 Petawawa 4.8 4.8 4.7 4.8 4.4 4.1 3.6 3.8 4.2 4.3 -23.1 SSS
52023 Kingston 8.3 6.5 6.8 6.3 5.8 5.3 5.6 5.4 5.6 6.5 -20.1 SSS
54012 Belleville 6.5 6.9 6.8 6.6 5.5 5.8 6.4 6.1 6.3 6.0 -9.9 Non-SSS
56051 Cornwall 6.9 7.7 7.0 6.9 6.4 5.9 6.3 5.9 6.0 6.5 -18.7 SSS
59006 Peterborough 6.3 7.4 6.9 6.8 5.8 5.8 6.3 6.0 5.6 6.5 -17.3 SSS
63203 Thunder Bay 5.4 6.3 6.6 6.5 4.9 5.1 6.0 5.1 5.5 6.6 -10.4 Non-SSS
71078 Sault Ste. Marie 5.6 5.6 6.0 5.9 4.9 5.0 5.5 4.8 4.5 5.8 -17.3 SSS
75010 North Bay 5.3 5.2 5.3 5.3 4.6 4.6 5.5 4.5 4.6 5.7 -7.8 Non-SSS
77233 Sudbury 5.1 5.7 6.0 6.3 5.4 5.0 5.4 5.0 5.1 5.8 -9.8 SSS

Notes:

  • From 2011-2012, measurements were taken by TEOM sampler operated at 30°C with a Sample Equilibration System (SES).
  • As of 2013, measurements taken by Synchronized Hybrid Ambient Real-time Particulate (SHARP) 5030.
  • An approximate correction factor was applied to the TEOM data prior to 2013 to be comparable to SHARP measurements and generate an approximate 10-year trend.
  • INS indicates there was insufficient data in any one quarter to calculate a valid annual mean.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • Station 15026 replaced station 15025 as the London site in 2013.
  • Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
  • Station 34021 replaced station 34020 as the Toronto North site in 2017.
  • Station 44029 was operated by the Halton Region prior to 2019.
  • Station 45027 replaced station 45026 as the Oshawa site in 2018.
  • Station 46090 replaced station 46089 as the Brampton site in 2017.
  • Station 52023 replaced station 52022 as the Kingston site in 2014.
  • Station 77233 replaced station 77219 as the Sudbury site in 2013.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for ground-level ozone (O3) 1h maximum

1h Maximum (ppb)
O3 1h AAQC: 80 ppb

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 128 89 78 89 95 78 89 82 81 82 -8.2 Non-SSS
12016 Windsor West 128 87 86 87 95 82 90 80 83 86 -8.2 Non-SSS
13001 Chatham 104 85 78 79 84 90 78 76 77 75 -12.1 SSS
14111 Sarnia 101 83 79 83 83 80 101 87 82 97 0.0 Non-SSS
15020 Grand Bend 124 86 90 87 91 82 100 85 93 104 3.6 Non-SSS
15026 London 88 82 82 77 82 78 76 70 77 78 -12.3 SSS
16015 Port Stanley 104 85 87 86 84 90 86 77 76 74 -17.3 SSS
18007 Tiverton 93 92 86 83 85 82 104 81 75 78 -16.1 SSS
21005 Brantford 88 74 80 79 84 74 76 74 74 79 -10.2 Non-SSS
26060 Kitchener 89 72 76 76 81 75 75 77 74 81 0.0 Non-SSS
27067 St. Catharines 98 96 70 73 80 73 75 70 75 73 -13.8 Non-SSS
28028 Guelph 94 73 79 79 82 76 78 74 70 83 -9.6 Non-SSS
29000 Hamilton Downtown 88 86 74 74 78 73 77 65 77 80 -7.7 Non-SSS
29118 Hamilton West 85 78 70 71 78 74 76 65 76 78 -3.0 Non-SSS
29214 Hamilton Mountain 91 86 79 79 76 81 80 70 79 80 -9.9 Non-SSS
33003 Toronto East 89 87 73 91 99 82 72 67 77 78 -14.4 Non-SSS
34021 Toronto North 92 87 82 90 85 82 83 77 95 86 -6.5 Non-SSS
35125 Toronto West 94 83 72 82 79 82 76 77 81 81 -2.7 Non-SSS
44008 Burlington 91 92 73 84 80 88 83 74 86 80 -8.5 Non-SSS
44017 Oakville 96 101 72 80 74 84 82 71 81 84 -9.4 Non-SSS
44029 Milton 94 93 80 80 79 74 81 77 77 84 -9.6 Non-SSS
45027 Oshawa 92 96 73 73 81 86 76 66 88 80 -11.7 Non-SSS
46090 Brampton 92 84 80 84 79 75 83 72 83 84 -4.9 Non-SSS
46108 Mississauga 81 83 76 79 79 78 79 65 80 81 0.0 Non-SSS
47045 Barrie 91 73 68 80 79 75 72 75 70 82 -9.9 Non-SSS
48006 Newmarket 105 72 87 92 94 85 91 88 87 81 -8.6 Non-SSS
49005 Parry Sound 94 77 74 86 74 74 80 68 73 80 -9.6 Non-SSS
49010 Dorset 82 69 79 78 74 69 77 64 66 70 -14.6 SSS
51001 Ottawa Downtown 76 67 64 69 73 71 72 57 64 68 -8.9 Non-SSS
51010 Petawawa 77 69 68 70 68 65 66 58 63 66 -11.7 SSS
52023 Kingston 92 79 81 74 82 94 78 68 72 78 -14.7 Non-SSS
54012 Belleville 87 92 80 77 96 86 85 73 81 82 -10.3 Non-SSS
56051 Cornwall 76 73 70 69 74 72 68 58 62 70 -15.8 SSS
59006 Peterborough 90 74 74 78 85 80 86 68 87 85 5.0 Non-SSS
63203 Thunder Bay 74 63 70 62 62 51 63 56 56 65 -14.6 Non-SSS
71078 Sault Ste. Marie 82 66 73 75 80 70 69 61 77 66 -11.0 Non-SSS
75010 North Bay 82 72 71 70 78 69 63 63 74 71 -11.0 Non-SSS
77233 Sudbury 84 76 73 67 80 69 70 75 62 56 -25.0 SSS

Notes:

  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • Station 15026 replaced station 15025 as the London site in 2013.
  • Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
  • Station 34021 replaced station 34020 as the Toronto North site in 2017.
  • Station 44029 was operated by the Halton Region prior to 2019.
  • Station 45027 replaced station 45026 as the Oshawa site in 2018.
  • Station 46090 replaced station 46089 as the Brampton site in 2017.
  • Station 52023 replaced station 52022 as the Kingston site in 2014.
  • Station 77233 replaced station 77219 as the Sudbury site in 2013.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for ground-level ozone (O3)

Annual mean (ppb)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 28.0 26.9 26.0 27.0 27.7 27.3 26.9 26.6 27.3 28.8 4.6 SSS
12016 Windsor West 28.0 26.7 27.2 26.5 27.7 27.0 27.0 27.3 26.0 29.4 4.5 SSS
13001 Chatham 29.5 29.6 29.3 29.6 29.6 29.5 28.7 29.2 29.1 30.4 0.4 Non-SSS
14111 Sarnia 29.7 28.6 27.1 27.8 28.8 28.4 29.0 29.2 26.7 30.2 0.5 Non-SSS
15020 Grand Bend 33.2 32.3 31.0 30.4 30.7 31.0 31.5 31.6 30.9 32.0 -0.9 Non-SSS
15026 London 27.7 28.7 28.1 27.9 28.2 28.1 27.6 26.8 27.7 28.9 0.8 Non-SSS
16015 Port Stanley 33.1 33.9 32.3 32.8 32.9 33.0 32.3 32.3 30.9 31.4 -6.0 SSS
18007 Tiverton 32.0 32.4 31.8 32.5 33.1 32.4 32.3 31.1 30.5 32.4 -2.0 Non-SSS
21005 Brantford 28.8 29.0 29.4 28.9 29.5 28.3 28.3 27.5 28.0 28.5 -4.6 SSS
26060 Kitchener 28.0 28.0 27.3 27.9 28.8 28.1 27.7 27.2 27.7 28.4 -0.4 Non-SSS
27067 St. Catharines 28.7 28.6 28.5 28.6 29.8 28.1 28.5 28.4 30.2 29.8 4.0 SSS
28028 Guelph 28.8 29.0 27.8 27.7 28.7 28.4 28.9 26.3 27.0 29.5 -0.8 Non-SSS
29000 Hamilton Downtown 25.7 25.0 25.3 25.9 26.7 25.6 25.6 24.4 26.3 26.4 3.9 Non-SSS
29118 Hamilton West 24.2 24.4 22.7 23.9 24.4 25.0 25.5 23.6 25.2 24.9 5.4 SSS
29214 Hamilton Mountain 30.2 29.5 29.1 29.4 29.5 29.1 29.3 27.5 29.3 28.7 -3.4 Non-SSS
33003 Toronto East 24.6 24.1 23.4 23.5 25.5 24.4 25.2 24.6 26.1 26.2 9.6 SSS
34021 Toronto North 25.7 25.3 25.3 25.7 25.9 24.0 25.5 24.1 26.0 26.4 2.5 Non-SSS
35125 Toronto West 21.5 21.5 21.1 21.3 22.1 22.1 22.3 21.8 23.4 22.8 9.6 SSS
44008 Burlington 26.7 26.4 25.5 26.5 27.6 27.1 27.6 26.6 28.3 27.4 7.9 SSS
44017 Oakville 27.7 28.3 27.2 27.4 27.1 27.4 28.7 27.1 28.0 28.8 3.3 Non-SSS
44029 Milton 26.5 27.6 27.1 27.2 27.2 27.5 28.1 26.9 26.8 27.2 0.4 Non-SSS
45027 Oshawa 27.0 27.2 27.2 26.2 27.2 27.9 25.8 24.4 26.4 26.9 -3.5 SSS
46090 Brampton 26.6 26.7 26.5 26.5 27.1 27.2 28.6 26.5 28.4 28.3 8.2 SSS
46108 Mississauga 25.6 25.2 25.4 25.4 26.0 26.2 26.1 24.5 25.6 26.2 1.7 Non-SSS
47045 Barrie 26.3 25.5 25.6 25.4 25.9 25.9 27.5 25.7 25.9 25.0 1.0 Non-SSS
48006 Newmarket 29.4 28.7 28.6 28.5 28.6 27.9 29.8 27.8 28.5 30.2 3.6 Non-SSS
49005 Parry Sound 30.1 30.4 29.6 30.4 29.6 29.7 30.8 29.8 29.9 30.3 1.9 Non-SSS
49010 Dorset 28.0 28.1 27.7 27.0 27.4 26.9 28.2 27.5 27.1 26.8 -2.1 Non-SSS
51001 Ottawa Downtown 26.0 25.6 24.8 25.6 25.6 25.5 26.4 25.9 25.2 25.8 1.0 Non-SSS
51010 Petawawa 27.7 27.6 26.8 26.7 26.4 25.8 27.3 27.3 26.9 26.7 -0.4 Non-SSS
52023 Kingston 32.7 30.3 31.4 30.3 30.5 30.4 30.5 29.9 30.1 30.2 -4.6 SSS
54012 Belleville 28.0 29.2 29.6 29.6 30.5 30.2 29.9 29.6 29.7 30.3 6.4 SSS
56051 Cornwall 27.1 26.9 27.3 27.9 27.1 27.2 27.6 26.9 26.4 26.7 -3.2 Non-SSS
59006 Peterborough 29.1 28.6 29.2 29.3 29.7 28.9 29.7 28.3 27.6 28.6 -1.9 Non-SSS
63203 Thunder Bay 25.0 26.3 23.4 24.0 23.2 23.4 24.3 23.7 22.9 24.4 -4.7 SSS
71078 Sault Ste. Marie 28.8 28.9 28.4 27.8 27.3 28.1 29.7 28.1 28.2 29.2 1.4 Non-SSS
75010 North Bay 26.1 27.4 26.7 27.0 26.4 26.4 26.0 26.4 26.2 26.4 -0.8 Non-SSS
77233 Sudbury 28.5 27.2 26.3 25.7 25.1 25.9 27.1 26.3 24.8 23.9 -9.7 SSS

Notes:

  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • Station 15026 replaced station 15025 as the London site in 2013.
  • Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
  • Station 34021 replaced station 34020 as the Toronto North site in 2017.
  • Station 44029 was operated by the Halton Region prior to 2019.
  • Station 45027 replaced station 45026 as the Oshawa site in 2018.
  • Station 46090 replaced station 46089 as the Brampton site in 2017.
  • Station 52023 replaced station 52022 as the Kingston site in 2014.
  • Station 77233 replaced station 77219 as the Sudbury site in 2013.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for ground-level ozone (O3) summer means (May - September)

Summer mean (ppb)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 36.8 32.5 30.9 33.3 33.4 32.8 33.7 31.4 32.7 33.8 0.8 Non-SSS
12016 Windsor West 35.7 30.9 30.9 31.8 33.0 31.8 32.4 31.2 30.6 33.8 -1.1 Non-SSS
13001 Chatham 36.6 34.2 32.4 34.4 32.9 33.1 32.1 31.9 32.5 33.6 -6.8 Non-SSS
14111 Sarnia 36.6 32.0 29.4 31.1 32.1 32.0 34.0 31.5 30.1 35.1 -0.4 Non-SSS
15020 Grand Bend 38.9 33.1 31.5 32.3 32.0 32.1 32.7 31.7 31.7 33.1 -2.7 Non-SSS
15026 London 34.4 30.9 29.5 31.0 30.4 29.8 30.5 27.4 29.1 31.0 -7.7 Non-SSS
16015 Port Stanley 38.4 36.9 33.7 35.6 35.2 35.0 35.3 33.7 32.8 34.3 -10.8 SSS
18007 Tiverton 36.0 32.5 30.8 33.3 34.1 32.2 32.9 29.7 30.5 33.0 -7.3 Non-SSS
21005 Brantford 33.5 30.1 29.9 31.2 32.2 29.4 30.4 28.3 29.5 31.1 -6.4 Non-SSS
26060 Kitchener 33.5 29.8 28.5 30.2 31.8 29.8 30.6 29.2 29.6 30.6 -1.6 Non-SSS
27067 St. Catharines 35.0 31.2 29.5 31.7 33.2 29.8 31.3 29.7 32.6 32.9 0.4 Non-SSS
28028 Guelph 34.5 30.4 28.9 30.2 31.2 29.6 31.7 27.3 29.0 31.1 -5.1 Non-SSS
29000 Hamilton Downtown 32.4 28.4 27.5 29.5 30.6 27.8 29.7 26.1 29.4 30.1 -2.4 Non-SSS
29118 Hamilton West 29.2 26.4 22.7 26.5 27.1 26.8 28.5 24.4 27.7 27.9 5.1 Non-SSS
29214 Hamilton Mountain 37.4 32.5 31.6 33.9 33.2 31.5 34.0 29.6 32.3 32.3 -6.6 Non-SSS
33003 Toronto East 30.6 27.1 25.9 27.7 29.7 26.0 29.2 26.0 28.8 29.2 0.5 Non-SSS
34021 Toronto North 32.7 29.4 28.6 30.7 30.7 26.3 30.4 25.9 29.3 29.8 -5.4 Non-SSS
35125 Toronto West 27.5 24.4 23.5 25.0 25.9 24.3 26.3 24.3 25.9 25.9 0.9 Non-SSS
44008 Burlington 32.5 29.2 27.4 30.1 30.5 29.0 31.8 28.8 31.2 30.4 1.4 Non-SSS
44017 Oakville 34.2 30.6 28.3 30.2 29.9 29.5 32.4 28.8 30.4 32.1 -2.5 Non-SSS
44029 Milton 32.2 30.6 28.2 30.4 30.6 29.6 34.3 28.9 28.6 30.6 -7.0 Non-SSS
45027 Oshawa 31.1 28.3 27.9 28.9 29.4 28.6 26.6 24.4 27.4 27.4 -11.1 SSS
46090 Brampton 32.7 29.5 28.9 30.3 31.2 29.5 32.7 28.2 31.0 31.6 1.8 Non-SSS
46108 Mississauga 30.4 26.5 26.5 28.0 28.5 27.2 28.3 24.9 27.0 28.5 -0.1 Non-SSS
47045 Barrie 29.7 25.6 25.4 26.8 27.4 25.6 29.0 24.7 25.8 25.1 -4.2 Non-SSS
48006 Newmarket 34.2 30.3 29.4 31.2 31.7 29.0 33.2 28.4 30.1 32.2 -4.5 Non-SSS
49005 Parry Sound 32.8 30.1 28.2 31.4 28.9 27.7 30.9 27.8 28.5 30.0 -6.4 Non-SSS
49010 Dorset 28.3 25.3 24.4 24.6 25.1 23.0 25.8 23.9 23.7 24.1 -6.7 Non-SSS
51001 Ottawa Downtown 29.3 26.5 24.6 27.8 27.5 25.3 27.6 25.6 25.7 27.4 -2.5 Non-SSS
51010 Petawawa 28.1 24.5 22.9 24.4 23.4 21.1 23.7 22.9 22.7 23.5 -8.2 SSS
52023 Kingston 38.5 32.4 32.7 32.2 33.3 30.9 33.1 30.0 31.3 32.0 -8.7 Non-SSS
54012 Belleville 32.7 30.6 30.4 33.2 33.7 30.9 32.4 30.0 31.0 32.8 0.2 Non-SSS
56051 Cornwall 30.7 28.1 27.0 29.7 28.7 27.1 29.4 26.1 26.3 27.8 -7.6 Non-SSS
59006 Peterborough 34.2 29.5 30.0 31.5 32.3 29.2 32.2 28.1 28.4 29.9 -7.2 Non-SSS
63203 Thunder Bay 25.3 24.7 22.7 23.6 22.0 20.4 22.1 21.8 21.3 24.4 -16.5 SSS
71078 Sault Ste. Marie 30.3 28.2 27.4 28.1 26.3 26.3 29.1 26.2 26.4 28.8 -5.2 Non-SSS
75010 North Bay 28.5 26.9 26.2 27.8 26.4 24.7 26.3 25.7 24.4 27.4 -7.4 Non-SSS
77233 Sudbury 29.8 28.0 27.0 27.7 26.6 25.8 28.8 25.9 23.7 23.4 -17.8 SSS

Notes:

  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • Station 15026 replaced station 15025 as the London site in 2013.
  • Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
  • Station 34021 replaced station 34020 as the Toronto North site in 2017.
  • Station 44029 was operated by the Halton Region prior to 2019.
  • Station 45027 replaced station 45026 as the Oshawa site in 2018.
  • Station 46090 replaced station 46089 as the Brampton site in 2017.
  • Station 52023 replaced station 52022 as the Kingston site in 2014.
  • Station 77233 replaced station 77219 as the Sudbury site in 2013.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for ground-level ozone (O3) winter means (January-April, October-December)

Winter mean (ppb)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 21.7 22.8 22.8 22.4 23.6 23.3 22.4 23.1 23.5 25.19 8.9 SSS
12016 Windsor West 22.3 23.4 24.5 22.7 23.9 23.6 23.1 24.4 22.8 26.32 6.6 Non-SSS
13001 Chatham 24.3 26.2 27.1 26.3 27.2 26.8 26.2 27.4 26.7 28.21 8.4 SSS
14111 Sarnia 24.7 26.2 25.4 25.4 INS 26.0 25.4 27.6 24.3 26.26 4.3 Non-SSS
15020 Grand Bend 29.1 31.8 30.6 29.1 29.8 30.2 30.7 31.6 30.5 31.32 6.3 Non-SSS
15026 London 22.9 26.9 27.1 25.8 26.6 26.9 25.6 26.4 26.7 27.49 6.1 Non-SSS
16015 Port Stanley 29.3 31.8 31.3 31.2 31.2 31.5 30.2 31.4 29.6 29.37 -6.0 Non-SSS
18007 Tiverton 29.2 32.4 32.7 31.9 32.4 32.6 31.9 32.1 30.6 32.0 -1.0 Non-SSS
21005 Brantford 25.4 28.3 28.8 27.2 27.7 27.5 26.7 26.9 27.0 26.8 -6.0 Non-SSS
26060 Kitchener 24.0 26.7 26.5 26.1 26.6 27.1 25.6 25.8 26.4 26.93 2.3 Non-SSS
27067 St. Catharines 24.1 26.8 27.9 26.3 27.2 27.0 26.4 27.5 28.5 27.8 8.9 SSS
28028 Guelph 24.8 28.0 27.0 26.0 26.8 27.5 26.9 25.7 25.6 28.5 0.5 Non-SSS
29000 Hamilton Downtown 20.9 22.5 23.7 23.3 23.9 24.2 22.6 23.2 24.1 23.82 7.4 Non-SSS
29118 Hamilton West 20.6 23.0 22.8 22.1 22.5 23.7 23.3 23.0 23.5 22.85 5.1 Non-SSS
29214 Hamilton Mountain 25.0 27.3 27.3 26.3 26.8 27.4 25.9 25.9 27.2 26.21 -0.5 Non-SSS
33003 Toronto East 20.3 22.0 21.6 20.5 22.5 23.3 22.4 23.5 24.2 24.07 17.2 SSS
34021 Toronto North 20.7 22.3 22.8 22.1 22.6 22.3 22.0 22.8 23.7 23.8 9.9 SSS
35125 Toronto West 17.2 19.5 19.4 18.6 19.4 20.5 19.4 20.1 21.6 20.74 18.2 SSS
44008 Burlington 22.5 24.4 24.1 23.8 25.6 25.7 24.7 25.2 26.2 25.29 10.7 SSS
44017 Oakville 23.1 26.6 26.5 25.3 25.1 25.9 26.0 26.0 26.3 26.49 6.3 Non-SSS
44029 Milton 22.2 25.5 26.3 24.9 24.7 25.9 24.9 25.5 25.6 24.81 0.2 Non-SSS
45027 Oshawa 24.1 26.4 26.7 24.3 25.6 27.3 25.4 24.5 25.7 26.73 2.3 Non-SSS
46090 Brampton 22.2 24.6 24.8 23.8 24.1 25.6 25.6 25.3 26.5 26.1 12.6 SSS
46108 Mississauga 22.2 24.3 24.7 23.6 24.2 25.5 24.6 24.2 24.7 24.67 4.7 Non-SSS
47045 Barrie 23.9 25.5 25.8 24.4 24.8 26.3 26.5 26.4 26.1 25.07 6.1 Non-SSS
48006 Newmarket 26.0 27.5 28.1 26.6 26.3 27.2 27.3 27.3 27.5 28.78 6.0 Non-SSS
49005 Parry Sound 28.1 30.6 30.6 29.8 30.0 31.1 30.7 31.3 31.0 30.6 4.1 Non-SSS
49010 Dorset 27.7 30.1 30.1 28.8 29.0 29.6 30.0 30.1 29.5 28.84 0.4 Non-SSS
51001 Ottawa Downtown 23.5 24.9 25.1 24.0 24.3 25.6 25.5 26.2 24.9 24.68 6.0 Non-SSS
51010 Petawawa 27.5 29.9 29.6 28.5 28.6 29.3 29.8 30.4 30.0 29.05 4.2 Non-SSS
52023 Kingston 28.6 28.8 30.4 28.9 28.5 30.2 28.6 29.9 29.2 28.94 0.7 Non-SSS
54012 Belleville 24.6 28.2 29.1 27.0 28.2 29.7 28.1 29.3 28.7 28.67 7.1 Non-SSS
56051 Cornwall 24.2 25.7 27.6 26.6 26.0 27.4 26.3 27.5 26.5 26.0 3.7 Non-SSS
59006 Peterborough 25.5 28.0 28.6 27.7 27.8 28.7 27.9 28.5 27.3 27.72 0.0 Non-SSS
63203 Thunder Bay 24.7 27.4 23.8 24.2 24.2 25.6 25.9 25.1 24.1 24.4 -0.4 Non-SSS
71078 Sault Ste. Marie 27.6 29.4 29.2 27.7 28.0 29.5 30.2 29.5 29.6 29.54 3.3 SSS
75010 North Bay 24.4 27.8 27.1 26.4 26.4 27.6 25.9 26.9 27.4 26.23 -0.9 Non-SSS
77233 Sudbury 27.6 26.6 25.8 24.3 24.0 26.1 26.0 26.7 25.7 24.39 -4.5 Non-SSS

Notes:

  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • Station 15026 replaced station 15025 as the London site in 2013.
  • Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
  • Station 34021 replaced station 34020 as the Toronto North site in 2017.
  • Station 44029 was operated by the Halton Region prior to 2019.
  • Station 45027 replaced station 45026 as the Oshawa site in 2018.
  • Station 46090 replaced station 46089 as the Brampton site in 2017.
  • Station 52023 replaced station 52022 as the Kingston site in 2014.
  • Station 77233 replaced station 77219 as the Sudbury site in 2013.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for sulphur dioxide (SO2)

Annual mean (ppb)
SO2 1y AAQC: 4 ppb

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 2.8 2.4 2.4 1.9 1.1 1.0 0.6 0.4 0.3 0.4 -91.6 SSS
12016 Windsor West 2.8 2.6 2.8 1.9 1.4 0.9 0.7 0.8 0.8 0.7 -74.1 SSS
14111 Sarnia 4.1 3.8 3.5 3.2 INS 1.7 1.9 1.9 2.0 2.2 -44.8 SSS
29000 Hamilton Downtown 4.8 4.8 5.1 4.3 3.2 3.5 5.0 4.8 3.7 3.8 -14.2 SSS
29214 Hamilton Mountain 3.7 2.8 2.9 2.6 1.8 1.8 2.4 3.5 2.5 3.2 -9.7 SSS
35125 Toronto West 0.6 0.6 0.7 1.0 0.6 0.5 0.3 0.3 0.2 0.2 -82.8 SSS
44029 Milton 1.3 1.2 1.3 1.1 0.9 0.7 0.7 INS INS INS N/A N/A
51001 Ottawa Downtown 0.3 0.3 0.3 0.4 0 0.1 0.2 0.2 0.1 0.2 -22.2 Non-SSS
71078 Sault Ste. Marie 0.6 0.8 0.8 0.8 0.6 0.7 0.8 0.7 0.6 0.8 0.0 Non-SSS
77233 Sudbury 1.3 2.8 2.4 2.4 2.1 1.3 1.2 1.2 0.9 0.9 -63.0 SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
  • Station 44029 was operated by the Halton Region prior to 2019.
  • Station 77233 replaced station 77219 as the Sudbury site in 2013.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for carbon monoxide (CO)

1h maximum (ppm)
CO 1h AAQC: 30 ppm

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 2.1 1.9 1.8 1.9 2.3 2.6 1.9 2.3 1.2 1.6 -17.2 Non-SSS
29000 Hamilton Downtown 1.7 2.0 2.9 1.3 1.4 2.1 1.7 1.9 1.2 1.5 -24.2 Non-SSS
35125 Toronto West 1.4 1.4 1.6 1.3 1.7 1.2 0.9 1.5 1.6 1.2 -14.2 Non-SSS
51001 Ottawa Downtown 0.9 0.9 0.8 0.8 0.9 0.7 1.0 0.7 0.9 0.8 -16.9 Non-SSS

Note:

  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for benzene

Annual mean (µg/m3)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.558 0.519 0.610 0.566 0.521 0.450 0.478 0.445 N/A 0.527 -24.5 SSS
14111 Sarnia 0.900 0.820 1.007 1.191 0.689 0.604 0.574 0.419 N/A 0.570 -45.3 SSS
15026 London 0.455 0.413 0.446 0.451 0.341 0.339 0.321 0.296 N/A N/A -47.2 SSS
26060 Kitchener 0.479 N/A 0.483 0.548 0.395 0.446 0.355 0.290 N/A N/A -50.1 SSS
29000 Hamilton Downtown 0.977 INS 0.899 1.092 0.675 0.569 0.639 0.568 N/A 0.613 -41.0 SSS
48006 Newmarket 0.371 0.406 0.422 0.425 0.328 0.385 INS 0.250 N/A N/A -37.9 SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • N/A indicates data not available.
  • The 2016 average for Sarnia is derived from data from May to December 2016.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
  • The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
  • The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.
  • SSS - Significant Sen's Slope (significant trend detected).

10-year trend for toluene

Annual mean (µg/m3)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12016 Windsor West 1.392 1.017 1.542 1.248 1.272 0.972 1.131 0.797 N/A 1.085 -40.7 SSS
14111 Sarnia 2.539 1.587 1.908 2.350 1.778 1.550 1.014 0.779 N/A 1.053 -49.6 SSS
15026 London 1.408 0.887 0.839 1.013 0.727 0.633 0.657 0.491 N/A N/A -70.8 SSS
26060 Kitchener 1.322 N/A 1.278 1.052 1.020 1.002 0.625 0.572 N/A N/A -67.1 SSS
29000 Hamilton Downtown 2.067 INS 2.229 2.249 1.642 1.296 0.862 0.817 N/A 1.314 -63.5 SSS
48006 Newmarket 0.877 0.916 0.732 1.340 1.118 0.807 INS 0.418 N/A N/A -47.5 SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • N/A indicates data not available.
  • The 2016 average for Sarnia is derived from data from May to December 2016.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
  • The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
  • The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.
  • SSS - Significant Sen's Slope (significant trend detected).

10-year trend for ethylbenzene

Annual mean (µg/m3)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.221 0.179 0.267 0.238 0.234 0.181 0.187 0.137 N/A 0.328 -39.4 SSS
14111 Sarnia 0.278 0.255 0.253 0.362 0.282 0.211 0.235 0.118 N/A 0.187 -45.8 SSS
15026 London 0.143 0.125 0.121 0.149 0.108 0.105 0.141 0.070 N/A N/A -52.2 SSS
26060 Kitchener 0.162 N/A 0.167 0.168 0.159 0.164 0.109 0.079 N/A N/A -53.3 SSS
29000 Hamilton Downtown 0.193 INS 0.192 0.210 0.186 0.187 0.129 0.126 N/A 0.172 -39.5 SSS
48006 Newmarket 0.115 0.134 0.125 0.249 0.215 0.130 INS 0.067 N/A N/A -37.1 Non-SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • N/A indicates data not available.
  • The 2016 average for Sarnia is derived from data from May to December 2016.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
  • The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
  • The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for m- and p-xylene

Annual mean (µg/m3)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.689 0.536 0.825 0.702 0.635 0.505 0.502 0.409 N/A 0.619 -45.2 SSS
14111 Sarnia 0.676 0.510 0.629 0.850 0.495 0.499 0.563 0.256 N/A 0.319 -38.0 SSS
15026 London 0.388 0.345 0.318 0.398 0.267 0.268 0.407 0.200 N/A N/A -50.8 SSS
26060 Kitchener 0.478 N/A 0.469 0.464 0.434 0.451 0.276 0.223 N/A N/A -61.0 SSS
29000 Hamilton Downtown 0.603 INS 0.594 0.621 0.518 0.532 0.359 0.398 N/A 0.486 -43.2 SSS
48006 Newmarket 0.333 0.362 0.334 0.582 0.484 0.350 INS 0.191 N/A N/A -40.2 SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • N/A indicates data not available.
  • The 2016 average for Sarnia is derived from data from May to December 2016.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
  • The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
  • The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.
  • SSS - Significant Sen's Slope (significant trend detected).

10-year trend for o-xylene

Annual mean (µg/m3)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.228 0.184 0.283 0.239 0.232 0.190 0.184 0.147 N/A 0.246 -33.6 SSS
14111 Sarnia 0.244 0.171 0.226 0.313 0.178 0.192 0.213 0.101 N/A 0.122 -38.0 SSS
15026 London 0.126 0.118 0.113 0.146 0.103 0.103 0.148 0.074 N/A N/A -38.1 SSS
26060 Kitchener 0.157 N/A 0.166 0.164 0.153 0.164 0.107 0.082 N/A N/A -58.0 SSS
29000 Hamilton Downtown 0.195 INS 0.206 0.216 0.189 0.198 0.131 0.145 N/A 0.183 -30.2 SSS
48006 Newmarket 0.116 0.126 0.134 0.218 0.192 0.128 INS 0.068 N/A N/A -38.0 Non-SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • N/A indicates data not available.
  • The 2016 average for Sarnia is derived from data from May to December 2016.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
  • The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
  • The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for 1,3-butadiene

Annual mean (µg/m3)

ID City/Town 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.048 0.036 0.042 0.035 0.032 0.034 0.028 0.028 N/A 0.038 -32.3 SSS
14111 Sarnia 0.205 0.209 0.124 0.216 0.089 0.077 0.088 0.054 N/A 0.071 -66.9 SSS
15026 London 0.040 0.023 0.025 0.026 0.020 0.035 0.025 0.025 N/A N/A -12.8 Non-SSS
26060 Kitchener 0.042 N/A 0.029 0.029 0.023 0.038 0.026 0.025 N/A N/A -32.3 SSS
29000 Hamilton Downtown 0.046 INS 0.032 0.037 0.025 0.039 0.028 0.028 N/A 0.036 -19.9 Non-SSS
48006 Newmarket 0.039 0.021 0.020 0.028 0.024 0.035 INS 0.025 N/A N/A 0.0 Non-SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • N/A indicates data not available.
  • The 2016 average for Sarnia is derived from data from May to December 2016.
  • Station 14111 replaced station 14064 as the Sarnia site in 2016.
  • The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
  • The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
  • The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

Canadian Ambient Air Quality Standard reporting

PM2.5 and ozone CAAQS metric values for designated sites across Ontario (2021)
Air zone area City/Town 24-hour PM2.5
(μg/m3)		 Annual PM2.5
(μg/m3)		 8-hour ozone
(ppb)
Sarnia Sarnia 19 7.3 70*(41)
Hamilton Hamilton Downtown 21 8.6 61(48)
Hamilton Hamilton Mountain 19 7.6 64*(50)
Sudbury Sudbury 15 5.3 56(43)
Sault Ste. Marie Sault Ste. Marie 14 5 59(44)
Northern Ontario Thunder Bay 17 5.7 51(44)
Southern Ontario Windsor Downtown 18 7.7 67*(41)
Southern Ontario Chatham 17 6.9 64*(43)
Southern Ontario London 18 7 62(46)
Southern Ontario Brantford 18 7.3 64*(49)
Southern Ontario Kitchener 19 7.2 61(48)
Southern Ontario Guelph 20 7.2 62(49)
Southern Ontario St. Catharines 17 6.6 63*(48)
Southern Ontario Burlington 18 6.9 64*(53)
Southern Ontario Oakville 18 6.9 65*(52)
Southern Ontario Milton 19 7.4 65*(52)
Southern Ontario Mississauga 19 7.1 61(48)
Southern Ontario Brampton 18 6.9 66*(52)
Southern Ontario Toronto West 18 7.2 63*(50)
Southern Ontario Toronto Downtown 21 8 65*(51)
Southern Ontario Toronto North 19 6.9 66*(50)
Southern Ontario Toronto East 20 7 61(45)
Southern Ontario Oshawa 18 6.2 63*(45)
Southern Ontario Barrie 19 7.1 58(44)
Southern Ontario Peterborough 18 6 61(46)
Southern Ontario Kingston 16 5.8 64*(46)
Southern Ontario Ottawa Downtown 17 6.1 57(47)

Note:

  • Designated sites normally refer to communities with populations greater than 100,000.
  • The CAAQS for 24h PM2.5 is 27 μg/m3 based on the 98th percentile measurement annually, averaged over three consecutive years.
  • The CAAQS for annual PM2.5 is 8.8 μg/m3 based on the annual average of the daily 24-hour average concentrations averaged over three consecutive years.
  • The CAAQS for ozone is 62 ppb based on the consecutive three-year average of the annual 4th highest daily maximum eight-hour running average.
  • The 24h PM2.5 and 8h ozone CAAQS metrics for Toronto Downtown are based on a 2-year average.
  • An asterisk denotes an exceedance of the CAAQS.
  • Value in parenthesis is the calculated 8h ozone CAAQS metric once the transboundary influence was removed.
NO2 and SO2 CAAQS metric values for designated sites across Ontario (2021)
Air zone area City/Town 1-hour NO2 (ppb) Annual NO2 (ppb) 1-hour SO2 (ppb) Annual SO2 (ppb)
Sarnia Sarnia 38 6.8 66 2.2
Hamilton Hamilton Downtown 44 10.2 82* 3.8
Hamilton Hamilton Mountain 40 6.3 61 3.2
Sudbury Sudbury 46 5.6 45 0.9
Sault Ste. Marie Sault Ste. Marie 30 3.9 33 0.8
Northern Ontario Thunder Bay 41 6.5 N/A N/A
Southern Ontario Windsor Downtown 43 9.6 13 0.4
Southern Ontario Chatham 30 5.1 N/A N/A
Southern Ontario London 30 5.2 N/A N/A
Southern Ontario Brantford 27 4.6 N/A N/A
Southern Ontario Kitchener 35 4.8 N/A N/A
Southern Ontario Guelph 34 5.5 N/A N/A
Southern Ontario St. Catharines 33 5.8 N/A N/A
Southern Ontario Burlington 42 8.7 N/A N/A
Southern Ontario Oakville 41 7.3 N/A N/A
Southern Ontario Milton 44 8.2 INS INS
Southern Ontario Mississauga 38 7 N/A N/A
Southern Ontario Brampton 43 6.5 N/A N/A
Southern Ontario Toronto West 49 12.9 7 0.2
Southern Ontario Toronto Downtown 51 12.7 N/A N/A
Southern Ontario Toronto North 45 9.3 6 0.2
Southern Ontario Toronto East 47 9.5 N/A N/A
Southern Ontario Oshawa 22 3.3 N/A N/A
Southern Ontario Barrie 40 5.6 N/A N/A
Southern Ontario Peterborough 34 4.1 N/A N/A
Southern Ontario Kingston 31 3.8 N/A N/A
Southern Ontario Ottawa Downtown 40 5.7 2 0.2

Note:

  • Designated sites normally refer to communities with populations greater than 100,000.
  • The CAAQS for 1h NO2 is 60 ppb is based on the 3-year average of the annual 98th percentile of the daily maximum 1-hour average NO2 concentrations.
  • The CAAQS for annual NO2 is 17.0 ppb based on the average over a single calendar year of all the 1h average NO2 concentrations.
  • The CAAQS for 1h SO2 is 70 ppb based on the 3-year average of the annual 99th percentile of the SO2 daily maximum 1-hour average concentrations.
  • The CAAQS for annual SO2 is 5.0 ppb based on the average over a single calendar year of all 1h average SO2 concentrations.
  • The 1h NO2 CAAQS metric for Toronto Downtown is based on a 2-year average.
  • An asterisk denotes an exceedance of the CAAQS.
  • INS denotes insufficient data to report a valid CAAQS metric.
  • N/A denotes not applicable (parameter not monitored at location).
PM2.5 and ozone CAAQS metric trends for designated sites across Ontario (2012-2021)
Air zone area City/Town 10-year trend (%) based on
24-hour PM2.5		 10-year trend (%) based on
annual PM2.5		 10-year trend (%) based on
8-hour ozone
Sarnia Sarnia -30.6 -46.9 0*
Hamilton Hamilton Downtown -26.6 -16.4 -7.9
Hamilton Hamilton Mountain -16 -13.4* -9.4
Sudbury Sudbury -14.1 -6.9* -6.8
Sault Ste. Marie Sault Ste. Marie -19.4 -15.5 -10.9
Northern Ontario Thunder Bay 0* -8.6* -10.7
Southern Ontario Windsor Downtown -19.6 -18.9 -11.4
Southern Ontario Chatham -22 -19.9 -16
Southern Ontario London -15.9* -23.5 -16.9
Southern Ontario Brantford -20.7* -13.4 -13.5
Southern Ontario Kitchener -16.3 -15.4 -11.4
Southern Ontario Guelph -6.1 -5.9* -12.5
Southern Ontario St. Catharines -19.7 -21.4 -10.3
Southern Ontario Burlington -20.2 -20.9 -5.6
Southern Ontario Oakville -16.8 -14.9 -6.3
Southern Ontario Milton -10.7* -9.5* -7.6
Southern Ontario Mississauga -17.5* -11.4 -10.3
Southern Ontario Brampton -19.6* -13 -4.3*
Southern Ontario Toronto West -20.2 -20.2 -10.7
Southern Ontario Toronto Downtown INS INS INS
Southern Ontario Toronto North -27.1 -27.3 -3.3
Southern Ontario Toronto East -13.8 -14.7 -12.9
Southern Ontario Oshawa -15.3 -18.4* -7.2*
Southern Ontario Barrie -15.9* 0* -11.8
Southern Ontario Peterborough -13.8* -14.6 -12.3
Southern Ontario Kingston -40.9 -37.8 -7.9
Southern Ontario Ottawa Downtown -22.2 -13.3* -6

Notes:

  • Designated sites normally refer to communities with populations greater than 100,000.
  • *Non-Significant Sen’s Slope (significant trend not detected).
  • INS denotes insufficient data for a valid 10-year trend.
NO2 and SO2 CAAQS metric trends for designated sites across Ontario (2012-2021)
Air zone area City/Town 10-year trend (%) based on
1-hour NO2		 10-year trend (%) based on
annual NO2		 10-year trend (%) based on
1-hour SO2		 10-year trend (%) based on
annual SO2
Sarnia Sarnia 0* -25 0* -44.8
Hamilton Hamilton Downtown -7.3 -17.2 7.9* -14.2
Hamilton Hamilton Mountain -7.0* -27 0* -9.7
Sudbury Sudbury INS -8.2 -87.8 -63
Sault Ste. Marie Sault Ste. Marie -8.8 -25 -11.3 0*
Northern Ontario Thunder Bay 0* -15.5 N/A N/A
Southern Ontario Windsor Downtown -17 -28.6 -80.7 -91.6
Southern Ontario Chatham -13.2 -19.5 N/A N/A
Southern Ontario London -23.1 -27.8 N/A N/A
Southern Ontario Brantford -18.2 -10.9 N/A N/A
Southern Ontario Kitchener -15.7 -27.1 N/A N/A
Southern Ontario Guelph -11.8 -25.5 N/A N/A
Southern Ontario St. Catharines -15.8 -32 N/A N/A
Southern Ontario Burlington -6.7 -24.4 N/A N/A
Southern Ontario Oakville -9.8 -17.7 N/A N/A
Southern Ontario Milton 0* -11.2 INS INS
Southern Ontario Mississauga -14 -29.9 N/A N/A
Southern Ontario Brampton -11.8* -35 N/A N/A
Southern Ontario Toronto West -12.9 -26.7 -51.1 -82.8
Southern Ontario Toronto Downtown INS INS N/A N/A
Southern Ontario Toronto North -8.7 -36.5 N/A N/A
Southern Ontario Toronto East -6.8 -41.6 N/A N/A
Southern Ontario Oshawa -25.7* -50.2 N/A N/A
Southern Ontario Barrie -7.0* -31.2 N/A N/A
Southern Ontario Peterborough 8.3* -32.6 N/A N/A
Southern Ontario Kingston 0* -11.2 N/A N/A
Southern Ontario Ottawa Downtown 0* -24.9 -84.4 -22.2*

Notes:

  • Designated sites normally refer to communities with populations greater than 100,000.
  • *Non-Significant Sen’s Slope (significant trend not detected).
  • INS denotes insufficient data for a valid 10-year trend.
  • N/A denotes not applicable (parameter not monitored at location).
  • Milton is based on 8 years of available data.

Management levels for CAAQS pollutants

Ozone
Management level 8-hour
2020
Red > 62 ppb
Orange 57 to 62 ppb
Yellow 51 to 56 ppb
Green ≤ 50 ppb
Fine particulate matter (PM2.5)
Management level 24-hour
2020		 Annual
2020
Red > 27 µg/m3 > 8.8 µg/m3
Orange 20 to 27 µg/m3 6.5 to 8.8 µg/m3
Yellow 11 to 19 µg/m3 4.1 to 6.4 µg/m3
Green ≤ 10 µg/m3 ≤ 4.0 µg/m3
Sulphur dioxide (SO2)
Management level 1-hour
2020		 Annual
2020
Red > 70 ppb > 5.0 ppb
Orange 51 to 70 ppb 3.1 to 5.0 ppb
Yellow 31 to 50 ppb 2.1 to 3.0 ppb
Green ≤ 30 ppb ≤ 2.0 ppb
Nitrogen dioxide (NO2)
Management level 1-hour
2020		 Annual
2020
Red > 60 ppb > 17.0 ppb
Orange 32 to 60 ppb 7.1 to 17.0 ppb
Yellow 21 to 30 ppb 2.1 to 7.0 ppb
Green ≤ 20 ppb ≤ 2.0 ppb

Air quality management actions by air zone area

Ontario air quality management actions across all air zones
Type Action Description
Air permissions and approvals framework Air Emissions Environmental Activity and Sector Registry Businesses that engage in certain routine and lower risk activities that generate air emissions must self-register online in the Environmental Activity and Sector Registry. They must submit information about their emissions to the MECP and follow standardized rules set out in guidance materials.
Air permissions and approvals framework Environmental Compliance Approvals Businesses with complex or unique types of operations must apply for an Environmental Compliance Approval (ECA). By law, a business must meet the specific conditions set out in the ECA. A business may also be inspected to ensure conditions are met.
Regulations Regulation 271/91: Gasoline Volatility O. Reg. 271/91 specifies upper limits for gasoline volatility in southern and northern Ontario for the summer driving season and requires petroleum facilities to track and report gasoline volatility limits during this period.
Regulations O. Reg. 455/94: Recovery of Gasoline Vapour in Bulk Transfers O. Reg. 455/9 reduces the discharge of gasoline vapour into the natural environment from terminals, bulk plants or service stations.
SO2 and NOx emissions trading program N/A This program, administered under O. Reg. 397/01 and O. Reg. 194/05, sets limits for NOx and SO2 emissions from the regulated facilities and allows for the transfer or trade of emission allowances and credits between facilities, to provide flexibility for compliance. footnote 1
Ambient air standards Ambient Air Quality Criteria (AAQC) The AAQCs set out air contaminant concentrations that are protective against adverse effects on health and/or the environment. AAQCs are used to assess general (ambient) air quality resulting from all sources of a contaminant to air.
Monitoring Provincial Air Monitoring Network and Air Quality Health Index (AQHI)

Ontario operates a network of 39 ambient (outside) air monitoring stations across the province that collect real-time air pollution data.

The AQHI evaluates air monitoring information and issues hourly forecasts to help you understand what the quality of the air around you means to your health.
Community engagement Air Standards/Local Air Quality External Working Group Ministry led facilitated discussions with industry, public health groups, environmental non-government organizations and some First Nations on matters relating to the local air quality regulation (O. Reg. 419/05).

Ontario air quality management actions by air zone

Northern Ontario (excluding Sault Ste. Marie and Sudbury)
CAAQS management level
  • PM2.5: yellow
  • Ozone: green
  • SO2: nil (no monitoring station in air zone)
  • NO2: orange
Type Action Description
Industry standard registrations Forest products industry standard
  • Imposes requirements on registered forest product facilities (e.g., sawmills) to reduce emissions of acrolein and other contaminants that can contribute to the development of PM2.5.
  • As of 2021, 13 facilities were registered in the Northern Ontario air zone.
Industry standard registrations Pulp and paper industry standard
  • Imposes requirements on registered pulp and paper facilities to reduce emissions of total reduced sulphur, acrolein and other contaminants which can contribute to the development of PM2.5.
  • As of 2021, 4 facilities were registered in the Northern Ontario air zone.
Southern Ontario (excluding Sarnia/St. Clair Township and Hamilton)
CAAQS management level
  • PM2.5: orange
  • Ozone: yellow
  • SO2: green
  • NO2: orange
Type Action Description
Industry standard registrations Metal finishers industry standard
  • Imposes requirements on registered metal finishing facilities to reduce emissions of various contaminants including hexavalent chromium.
  • As of 2021, 7 facilities were registered in the Southern Ontario air zone.
Industry standard registrations Foundries industry standard
  • Imposes requirements on registered foundries (e.g., metal works facilities) to reduce emissions of various contaminants including SO2 and NO2.
  • As of 2021, 16 facilities were registered in the Southern Ontario air zone.
Industry standard registrations Petroleum refining industry standard
  • Requirements related to sources of benzene and benzo[a]pyrene from storage vessels, equipment leaks, sewage treatment operations and truck and railcar product loading racks and marine vessel loading berths.
  • As of 2021, 1 facility was registered in the Southern Ontario air zone.
Site-specific standards ADM Agri-Industries Company in Windsor
  • Requires action to reduce emissions of, and sets an alternative air standard for, suspended particulate matter emissions at a grain handling and oilseed processing facility.
  • This site-specific standard was issued in December 2018 and expires in 2028.
Site-specific standards Stelco Lake Erie Works in Nanticoke
  • Requires action to reduce emissions of, and sets an alternative air standard for, suspended particulate matter, benzene and benzo[a]pyrene.
  • These site-specific standards were issued in March 2015 and May 2016 and all will expire in 2023.
Site-specific standards Harsco Canada Corp in Nanticoke
  • Requires action to reduce emissions of, and sets an alternative air standard for, suspended particulate matter emissions at a slag processing operation located on site at Stelco’s Lake Erie Works facility in Nanticoke.
  • This site-specific standard was issued in March 2015 and expires in 2023.
Site-specific standards Owens Corning Composite Materials Canada LP in Guelph
  • Requires action to reduce emissions of, and sets an alternative air standard for, hexavalent chromium.
  • This site-specific standard was issued in July 2016 and will expire in 2026.
Site-specific standards Oxy Vinyls Canada Co. in Thorold
  • Requires action to reduce emissions of, and sets an alternative air standard for, vinyl chloride air emissions
  • This site-specific standard was issued in February 2017 and will expire in 2027.
Sudbury
CAAQS management level
  • PM2.5: yellow
  • Ozone: green
  • SO2: yellow
  • NO2: orange
Type Action Description
Industry standard registrations Metal finishers industry standard
  • Imposes requirements on registered metal finishing facilities to reduce emissions of various contaminants including hexavalent chromium.
  • As of 2021, 1 facility was registered in the Sudbury air zone.
Site-specific standards Glencore Canada Corporation
  • Requires action to reduce emissions of, and sets an alternative air standards for, cadmium, nickel and nickel compounds and sulphur dioxide.
  • These site-specific standards were issued between 2012 and 2020 and expire between 2022 and 2030 (see links for more details).
Site-specific standards Vale Canada Ltd. footnote 2
  • Requires action to reduce emissions of, and sets an alternative air standard for, nickel and nickel compounds.
  • This site-specific standard was issued in December 2021 and will expire in 2030.
Sault Ste. Marie
CAAQS management level
  • PM2.5: yellow
  • Ozone: green
  • SO2: nil (no monitoring station in air zone)
  • NO2: orange
Type Action Description
Industry standard registrations Forest products industry standard
  • Imposes requirements on registered forest product facilities (e.g., sawmills) to reduce emissions of acrolein and other contaminants that can contribute to the development of PM2.5.
  • As of 2021, 1 facility was registered in the Sault Ste. Marie air zone.
Site-specific standards Algoma Steel Inc.
  • Requires action to reduce emissions of, and sets an alternative air standards for, benzene, benzo[a]pyrene and suspended particulate matter.
  • These site-specific standards were issued between 2015 and 2017 and expire between 2022 and 2023.
Sarnia/St. Clair Township
CAAQS management level
  • PM2.5: orange
  • Ozone: green
  • SO2: orange
  • NO2: orange
Type Action Description
Regulations O. Reg. 530/18: Air Pollution – Discharge of Sulphur Dioxide from Petroleum Facilities
  • Improves how acid gas flaring events are managed and strengthens accountability through reporting, monitoring and environmental penalties.
Regulations Regulation 350 - Lambton Industry Meteorological Alert (LIMA)
  • Public alerts are issued if the running daily (24-hr) average sulphur dioxide concentration reaches 0.07 parts per million at any of the monitoring stations in the LIMA network.
Policy Cumulative effects assessment in air approvals
  • Guides decisions on Environmental Compliance Approval (ECA) applications for new or expanding facilities in Sarnia & Hamilton with benzene emissions.
Industry standard registrations Petroleum refining industry standard
  • Requirements related to sources of benzene and benzo[a]pyrene from storage vessels, equipment leaks, sewage treatment operations and truck and railcar product loading racks and marine vessel loading berths.
  • As of 2021, 3 facilities were registered in the Sarnia/St. Clair Township air zone.
Industry standard registrations Petrochemical industrial standard
  • Requirements related to sources of benzene and butadiene from storage vessels, equipment leaks, sewage treatment operations and truck and railcar product loading racks and marine vessel loading berths.
  • As of 2021, 4 facilities were registered in the Sarnia/St. Clair Township air zone.
Enhanced monitoring Property line monitoring, petroleum refining and petrochemical industries
  • Facilities registered to the Petroleum Refining and Petrochemical Industry Standards are required to monitor benzene or 1,3-butadiene levels at their fence lines (known as “property line monitoring”) and provide the results on a public website within 60 days.
Enhanced monitoring SLEA air monitoring network
  • Nine ambient air monitoring stations in the Sarnia area operated by the Sarnia-Lambton Environmental Association (SLEA), an industrial cooperative of 18 facilities operating in Lambton County.
Enhanced community engagement Sarnia Area Environmental Health Project
  • This project assesses the impact of air exposures and other stressors in the Sarnia Area on human health.
Enhanced community engagement Clean Air Sarnia Area (CASA)
  • Community advisory panel is made up of representatives from the public, government, First Nations, and industry, who are dedicated to providing the community with a clear understanding of ambient air quality in the Sarnia area. Roles include information sharing, identifying and researching local air quality issues, provide info and recommendations to MECP and Sarnia-Lambton Environmental Association, informing public of local air quality, also maintenance of public CASA website which contains air monitoring data from SLEA and MECP as well as 1 AQHI station.
Enhanced strategic planning Sarnia action plan
  • Aims to drive air quality improvements by taking action across several broadly defined categories, including enhanced internal diagnostics, strategic planning of ministry activities, air monitoring improvements, enhancements to internal and external communications, improved incident response, and approvals and enforcement considerations.
  • One aspect of this is enhanced inspections, which includes assessments of the operation and maintenance of equipment such as above ground storage tanks and vapour recovery systems, acid gas flares, wastewater treatment plant monitoring and assessing compliance with regulatory limits of sulphur content in boiler fuel. Since 2015, 108 storage tanks have been inspected. Using hand-held air monitoring equipment, the ministry is conducting proactive monthly air quality monitoring within priority industrial areas based on previous air quality monitoring and a history of community odour complaints.
Hamilton
CAAQS management level
  • PM2.5: orange
  • Ozone: yellow
  • SO2: red
  • NO2: orange
Type Action Description
Policy Cumulative effects assessment in air approvals
  • Guides decisions on Environmental Compliance Approval (ECA) applications for new or expanding facilities in Sarnia & Hamilton with benzene emissions.
Policy Local Poor Air Quality Notification Protocol
  • The Local Poor Air Quality Notification (LPAQN) protocol is a program through which companies are asked to voluntarily implement operational practices and control measures to reduce releases of dust and particulate matter to air during poor air quality events. The protocol addresses poor air quality events that are the result of unique conditions in Hamilton that are conducive to the build-up of pollutants in the lower part of the City. Approximately 33 industries and municipal operations participate and enact poor air quality plans when a Notification is issued in response to defined considerations.
Industry standard registrations Foundries industry standard
  • Imposes requirements on registered foundries (e.g., metal works facilities) to reduce emissions of various contaminants including SO2 and NO2.
  • As of 2021, 1 facility was registered in the Hamilton air zone.
Site-specific standards Stelco
  • Requires action to reduce emissions of, and sets an alternative air standards for, benzene, benzo[a]pyrene, and suspended particulate matter.
  • These site-specific standards were issued in 2015 and 2016 and expire in 2023.
Site-specific standards ArcelorMittal Dofasco
Site-specific standards Harsco Canada Corp
  • Requires action to reduce emissions of, and sets an alternative air standard for, suspended particulate matter and manganese and manganese compound emissions at a slag processing operation located on site at the ArcelorMittal Dofasco facility in Hamilton.
  • These site-specific standards were issued in May 2016 and expires in 2023.
Site-specific standards Rain Carbon (formerly Ruetgers Canada Inc.)
  • Requires action to reduce emissions of, and sets an alternative air standards for, benzene and benzo(a)pyrene.
  • These site-specific standards were issued in 2017 and expire in 2022.
Site-specific standards Carmeuse Lime (Canada) Limited
  • alternative air standards for, calcium oxide and suspended particulate matter.
  • These site-specific standards were issued in 2018 and expire in 2028.
Enhanced monitoring Hamilton Air Monitoring Network (HAMN)
  • A comprehensive air monitoring network, made up of industry-operated and ministry-operated stations that measure impacts from industrial operations and is used to assess ambient air conditions in Hamilton. The ministry conducts regular audits of industry station in the network since 2003. HAMN provides the ministry with real-time air quality alerts based on agreed thresholds as well as monthly exceedance reports and quarterly and annual summary reports.
Enhanced community engagement Clean Air Hamilton
  • Clean Air Hamilton is a multi-stakeholder, member-based organization dedicated to improving air quality in Hamilton. The ministry has been a long-standing member of Clean Air Hamilton for over 20 years. Staff from the ministry’s West Central Region participate in monthly Clean Air Hamilton meetings to discuss updates on local air quality initiatives and activities and respond to questions regarding ministry air quality related activities in Hamilton. The ministry provides supporting information for the Clean Air Hamilton annual progress report.
Enhanced strategic planning Hamilton Air Action Plan (HAAP)
  • The HAAP is a placed-based approach to address air quality issues in the City of Hamilton, in collaboration with other ministry divisions and groups. The overall goal of the HAAP is to continue to reduce concentrations of priority air contaminants in Hamilton, to collectively strategize on and implement actions and compliance approaches to improve air quality in the City of Hamilton. This is achieved through four key project areas: Compliance Activities and Assessment; Air Compliance Approaches and Policies; Air Quality Monitoring and Communication, Outreach and Planning.

Changes in air quality management actions since 2021

Approvals/programs/regulations that have since ended
Air zone Program/Regulation Description
All Ontario Air Zones SO2 and NOx emissions trading program This program ended when the regulations were revoked on February 5, 2021.
Sudbury Glencore Canada Corporation site specific standard for sulphur dioxide Site-specific standard for sulphur dioxide ended on January 1, 2022, when O. Reg. 652/21: Air Pollution – Discharge of Sulphur Dioxide from Nickel Smelting and Refining Facilities in the Sudbury Area took effect.
Sudbury Vale Canada Ltd. site-specific standard for sulphur dioxide Site-specific standard for sulphur dioxide ended on January 1, 2022, when O. Reg. 652/21: Air Pollution – Discharge of Sulphur Dioxide from Nickel Smelting and Refining Facilities in the Sudbury Area took effect.
Hamilton Rain Carbon (formerly Ruetgers Canada Inc.) site-specific standards for benzene and benzo(a)pyrene These site-specific standards expired in 2022.
New actions since 2021
Air zone Program/Regulation Description
Northern Ontario Foundries industry standard
  • Imposes requirements on registered foundries (e.g., metal works facilities) to reduce emissions of various contaminants including SO2 and NO2.
  • On January 12, 2023, a facility registered to this industry standard bringing the total number of registered facilities in the Northern Ontario Air Zone to one.
Southern Ontario Ontario Regulation 88/22 - Air Pollution - Discharge of Sulphur Dioxide from Petroleum Facilities
  • This regulation came into effect on February 25, 2022. It requires actions to reduce sulphur dioxide emissions and applies to specific facilities including the PCLI facility located in Nanticoke.
Southern Ontario Metal finishers industry standard
  • Imposes requirements on registered metal finishing facilities to reduce emissions of various contaminants including hexavalent chromium.
  • On February 25, 2022, an additional facility registered to this industry standard bringing the total number of registered facilities in the Southern Ontario Air Zone to 8.
Southern Ontario OPG Lennox site-specific standards
  • On March 15, 2023, the MECP issued multiple site-specific standards requiring action to reduce emissions of, and set an alternative air standard for, SO2, NOx, and sulfuric acid from natural gas/RFO electricity generation. These site-specific standards expire in 2033.
Southern Ontario Asphalt mix industry standard
  • Requirements to control emissions of various compounds, including metals, particulate, and VOCs from asphalt mixing, storage, crushing, roads, and dryers/oil burners and generators.
  • On January 12, 2023, a facility registered to this industry standard bringing the total number of registered facilities in the Southern Ontario Air Zone to one.
Sudbury O. Reg 652/21:  Air Pollution – Discharge of Sulphur Dioxide from Nickel Smelting and Refining Facilities in the Sudbury Area
  • This regulation came into effect on January 1, 2022. It addresses sulphur dioxide air emissions from the nickel smelting and refining industry in the Sudbury area that will replace certain requirements under the Local Air Quality Regulation.
Sarnia/St. Clair Township Ontario Regulation 88/22 - Air Pollution - Discharge of Sulphur Dioxide from Petroleum Facilities
  • This regulation came into effect on February 25, 2022. It requires actions to reduce sulphur dioxide emissions and applies to specific facilities including the IOL – Sarnia facility, the Shell Facility, and the Suncor facility in the Sarnia/St. Clair Township air zone.

AQHI and air quality alert program reporting

2021 Air Quality Health Index summary
Station ID City/Town No. of valid hours Low risk AQHI=1 Low risk AQHI=2 Low risk AQHI=3 Moderate risk AQHI=4 Moderate risk AQHI=5 Moderate risk AQHI=6 High risk AQHI=7 High risk AQHI=8 High risk AQHI=9 High risk AQHI=10 Very high risk AQHI=+ No. of days at least 1 hour > 6
12008 Windsor Downtown 8721 1.55 42.99 41.30 13.31 0.70 0.13 0.02 0 0 0 0 1
12016 Windsor West 8475 1.90 43.89 40.60 11.81 1.58 0.17 0.05 0 0 0 0 3
13001 Chatham 8613 8.02 55.74 29.58 6.41 0.22 0.02 0 0 0 0 0 0
14111 Sarnia 8397 5.09 55.19 26.89 10.56 2.18 0.02 0.07 0 0 0 0 2
15020 Grand Bend 8645 15.48 60.45 19.94 3.69 0.23 0 0.19 0.02 0 0 0 6
15026 London 8728 11.55 53.36 28.43 6.46 0.21 0 0 0 0 0 0 0
16015 Port Stanley 8079 15.20 60.07 19.94 4.57 0.21 0.01 0 0 0 0 0 0
18007 Tiverton 8070 11.88 62.29 21.73 3.98 0.11 0 0 0 0 0 0 0
21005 Brantford 8681 14.51 54.66 25.46 4.99 0.38 0 0 0 0 0 0 0
26060 Kitchener 8533 12.53 55.22 27.24 4.68 0.33 0 0.01 0 0 0 0 1
27067 St. Catharines 8498 8.66 53.82 31.89 5.34 0.28 0 0 0 0 0 0 0
28028 Guelph 8666 10.29 52.35 30.04 6.53 0.74 0 0.05 0 0 0 0 1
29000 Hamilton Downtown 8571 5.16 42.95 37.45 11.03 2.81 0.40 0.21 0 0 0 0 2
29118 Hamilton West 8619 6.53 47.77 34.93 8.97 1.46 0.30 0.03 0 0 0 0 2
29214 Hamilton Mountain 8679 8.58 52.94 29.95 7.19 1.13 0.21 0 0 0 0 0 0
31129 Toronto Downtown 8162 1.94 34.39 47.65 12.99 2.52 0.32 0.12 0.04 0 0.04 0 5
33003 Toronto East 8669 5.48 50.06 33.91 9.33 1.14 0.07 0 0 0 0 0 0
34021 Toronto North 8406 8.09 48.01 33.02 9.31 1.50 0.02 0.04 0 0 0 0 1
35125 Toronto West 8624 3.46 44.10 40.05 10.44 1.63 0.30 0.02 0 0 0 0 2
44008 Burlington 8704 6.61 48.86 34.01 9.23 1.30 0 0 0 0 0 0 0
44017 Oakville 8563 6.63 52.63 32.43 7.19 0.96 0.13 0.02 0 0 0 0 1
44029 Milton 8646 6.52 52.29 31.64 8.37 1.08 0.06 0.03 0 0 0 0 1
45027 Oshawa 8725 23.97 57.56 15.01 3.17 0.28 0.01 0 0 0 0 0 0
46090 Brampton 8659 9.46 53.67 30.57 5.55 0.68 0.03 0.03 0 0 0 0 1
46108 Mississauga 8364 11.31 53.78 27.81 6.43 0.62 0.04 0.01 0 0 0 0 1
47045 Barrie 8464 19.70 56.40 19.98 3.54 0.30 0.02 0.02 0.04 0 0 0 2
48006 Newmarket 8742 12.21 57.26 24.61 5.44 0.47 0 0.01 0 0 0 0 1
49005 Parry Sound 8748 19.83 61.01 16.43 2.64 0.09 0 0 0 0 0 0 0
49010 Dorset 8734 29.20 55.10 13.69 1.98 0.03 0 0 0 0 0 0 0
51001 Ottawa Downtown 8657 19.06 53.61 23.98 3.34 0.01 0 0 0 0 0 0 0
51010 Petawawa 8648 28.67 57.49 12.86 0.98 0 0 0 0 0 0 0 0
52023 Kingston 8693 13.45 58.64 23.19 4.19 0.53 0 0 0 0 0 0 0
54012 Belleville 8502 13.03 61.03 21.92 3.58 0.42 0 0.01 0 0 0 0 1
56051 Cornwall 8572 17.50 56.77 21.79 3.79 0.12 0.03 0 0 0 0 0 0
59006 Peterborough 8711 19.37 54.12 21.19 4.86 0.42 0.03 0.01 0 0 0 0 1
63203 Thunder Bay 8740 17.46 56.17 22.67 3.01 0.58 0.07 0.03 0.01 0 0 0 2
71078 Sault Ste. Marie 8244 18.17 57.52 20.35 3.71 0.19 0.04 0.01 0 0 0 0 0
75010 North Bay 8390 23.71 58.99 14.86 2.38 0.06 0 0 0 0 0 0 1
77233 Sudbury 8647 22.26 60.54 14.95 2.07 0.10 0.02 0.01 0.02 0.01 0 0 1
2021 air quality alert summary
Air quality forecast region Special air quality statement Smog and air health advisory
Algonquin 1 0
Atikokan - Upsala - Quetico 2 0
Attawapiskat 1 0
Bancroft - Bon Echo Park 1 0
Barrie - Orillia - Midland 1 0
Belleville - Quinte - Northumberland 2 0
Big Trout Lake - Sachigo Lake 1 0
Brockville - Leeds and Grenville 1 0
Burk's Falls - Bayfield Inlet 1 0
Chapleau - Gogama 1 0
City of Hamilton 4 0
City of Ottawa 1 0
City of Thunder Bay 1 0
City of Toronto 2 0
Cornwall - Morrisburg 1 0
Dryden - Ignace 2 0
Dufferin - Innisfil 2 0
Dunnville - Caledonia - Haldimand 2 0
Elgin 2 0
Elliot Lake - Ranger Lake 1 0
Fort Frances - Rainy Lake 3 0
Fort Hope - Webequie 1 0
Fort Severn 1 0
Geraldton - Manitouwadge - Hornepayne 1 0
Greater Sudbury and Vicinity 1 0
Grey - Bruce 1 0
Haliburton 1 0
Halton - Peel 2 0
Huron - Perth 2 0
Kapuskasing - Hearst 1 0
Kenora - Nestor Falls 4 0
Kingston - Prince Edward 2 0
Kirkland Lake - New Liskeard - Temagami 1 0
Lake Nipigon - Wabakimi 1 0
London - Middlesex 2 0
Manitoulin - Northshore - Killarney 1 0
Moosonee - Fort Albany 1 0
Niagara 2 0
Nipigon - Marathon - Superior North 1 0
North Bay - West Nipissing 1 0
Oxford - Brant 2 0
Parry Sound - Muskoka 1 0
Peawanuck 1 0
Peterborough - Kawartha Lakes 2 0
Pickle Lake - Wunnummin Lake 2 0
Prescott and Russell 1 0
Red Lake - Ear Falls 4 0
Renfrew - Pembroke - Barry's Bay 1 0
Sandy Lake - Pikangikum 3 0
Sarnia - Lambton 3 0
Sault Ste. Marie - Superior East 1 0
Simcoe - Delhi - Norfolk 2 0
Sioux Lookout - Savant Lake 2 0
Smiths Falls - Lanark - Sharbot Lake 1 0
Stirling - Tweed - South Frontenac 2 0
Superior West 1 0
Timmins - Cochrane 1 0
Waterloo - Wellington 2 0
Wawa - White River - Pukaskwa 1 0
Windsor - Essex - Chatham - Kent 2 0
York - Durham 2 0
Ontario 9 0

Roadside air monitoring in Ontario

2021 ultrafine particles annual statistics

Unit: particles per cubic centimetre (#/cm3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
34021 Toronto North 4905 Dufferin St., ECCC 8657 3,527 6,011 8,556 12,040 18,780 35,376 10,261.7 77,780 25,821
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 8225 8,419 18,282 31,860 51,330 92,080 171,512 42,579.1 277,000 146,537
83133 Toronto Island 535 Lakeshore Ave., Hanlan's Point 7026 2,060 3,657 5,206 7,338 12,145 23,925 6,415.1 55,900 14,756

 

2021 black carbon annual statistics

Unit: micrograms per cubic metre (µg/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
12008 Windsor Downtown 467 University Ave. W. 8179 0.15 0.27 0.39 0.56 0.94 2.00 0.49 6.31 1.41
12016 Windsor West College Ave./South St. 8635 0.16 0.27 0.40 0.56 0.97 2.12 0.50 4.76 1.54
29000 Hamilton Downtown Elgin St./Kelly St. 8603 0.14 0.26 0.41 0.63 1.21 2.68 0.57 5.56 2.37
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 7097 0.12 0.23 0.34 0.50 0.89 1.77 0.44 3.52 1.60
34021 Toronto North 4905 Dufferin St., ECCC 8735 0.12 0.21 0.34 0.52 0.96 2.13 0.47 5.15 1.99
35033 Etobicoke South 185 Judson St. 8737 0.21 0.37 0.54 0.77 1.29 3.00 0.69 11.26 2.57
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 8577 0.31 0.56 0.87 1.40 2.46 4.59 1.18 7.71 3.88
83133 Toronto Island 535 Lakeshore Ave., Hanlan's Point 8702 0.00 0.13 0.23 0.38 0.75 1.81 0.33 2.96 1.58

 

2021 iron in PM2.5 annual statistics

Unit: nanograms per cubic metre (ng/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
29000 Hamilton Downtown Elgin St./Kelly St. 7682 15 30 49 83 233 862 104.0 3309 613.4
35033 Etobicoke South 185 Judson St. 5116 21 40 63 95 173 441 87.6 3590 324.7
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 7565 47 94 171 317 582 1095 257.0 2262 654.6

 

2021 copper in PM2.5 annual statistics

Unit: nanograms per cubic metre (ng/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
29000 Hamilton Downtown Elgin St./Kelly St. 7682 1.2 1.6 2.2 3.5 9.0 32.7 4.4 507.5 34.7
35033 Etobicoke South 185 Judson St. 5116 2.0 2.7 3.3 4.1 6.3 24.1 4.4 426.5 57.4
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 7565 2.7 3.9 6.3 10.9 17.7 33.1 9.8 1646.0 209.1

 

2021 manganese in PM2.5 annual statistics

Unit: nanograms per cubic metre (ng/m3)
Mn in PM2.5 24h AAQC: 100 ng/m3

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h		 Number of times above 24h criteria
29000 Hamilton Downtown Elgin St./Kelly St. 7682 0.0 0.3 0.8 1.7 6.4 51.2 3.4 529.7 35.3 0
35033 Etobicoke South 185 Judson St. 5116 0.4 0.9 1.4 2.4 4.8 13.1 2.3 51.9 9.6 0
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 7565 0.9 1.8 2.7 4.1 7.2 16.0 3.6 102.6 17.2 0

 

2021 lead in PM2.5 annual statistics

Unit: nanograms per cubic metre (ng/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum 24h
29000 Hamilton Downtown Elgin St./Kelly St. 7681 0.6 1.4 2.3 3.4 7.3 23.4 3.5 90.4 14.6
35033 Etobicoke South 185 Judson St. 5115 0.4 0.8 1.4 2.3 4.8 26.5 2.8 174.3 27.0
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 7570 0.7 1.2 1.9 3.0 5.4 16.1 2.9 192.0 26.8

 

2021 selenium in PM2.5 annual statistics

Unit: nanograms per cubic metre (ng/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
29000 Hamilton Downtown Elgin St./Kelly St. 7682 0.03 0.12 0.25 0.55 1.59 6.41 0.68 28.17 5.68
35033 Etobicoke South 185 Judson St. 5116 0.00 0.05 0.20 0.47 1.42 5.98 0.60 29.06 3.93
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 7565 0.07 0.17 0.27 0.46 1.20 8.57 0.66 47.27 6.43

 

2021 zinc in PM2.5 annual statistics

Unit: nanograms per cubic metre (ng/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
29000 Hamilton Downtown Elgin St./Kelly St. 7682 2.2 5.1 8.8 15.3 45.1 298.4 23.9 1,529 184.8
35033 Etobicoke South 185 Judson St. 5116 2.7 5.5 9.0 14.7 30.5 105.7 15.1 780 64.5
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 7565 4.6 8.1 11.8 17.3 35.7 136.2 19.5 1,791 159.1

 

2021 organics in PM2.5 annual statistics

Unit: micrograms per cubic metre (µg/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 6481 1.1 2.0 3.1 4.5 7.7 17.7 3.94 50.7 23.57

 

2021 sulphate in PM2.5 annual statistics

Unit: micrograms per cubic metre (µg/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 6481 0.1 0.2 0.4 0.7 1.3 2.6 0.56 4.4 3.02

 

2021 nitrate in PM2.5 annual statistics

Unit: micrograms per cubic metre (µg/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 6481 0.1 0.2 0.4 0.8 2.9 11.1 1.14 18.7 15.17

 

2021 ammonium in PM2.5 annual statistics

Unit: micrograms per cubic metre (µg/m3)

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Maximum
1h		 Maximum
24h
83126 Toronto Hwy 401 Hwy 401 at 125 Resources Rd. 6481 0.0 0.1 0.4 0.9 2.1 8.1 0.89 11.8 9.69

 

6-year trend for ultrafine particles

Annual mean (#/cm3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
34021 Toronto North 11953 12074 12293 10873 9056 10262 -20.1 SSS
83126 Toronto Hwy 401 43280 39053 37984 39831 40635 42579 11.5 SSS
83133 Toronto Island INS INS INS 6693 6126 6415 -12.3 SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • SSS - Significant Sen's Slope (significant trend detected).

6-year trend for black carbon

Annual mean (µg/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
12008 Windsor Downtown 0.53 0.50 0.57 0.59 0.43 0.49 -15.2 Non-SSS
12016 Windsor West 0.70 0.65 0.60 0.59 0.45 0.50 -34.8 SSS
29000 Hamilton Downtown 0.51 0.71 0.72 0.67 0.57 0.57 -4.6 Non-SSS
33003 Toronto East 0.62 0.62 0.45 0.45 0.45 0.44 -33.9 SSS
34021 Toronto North 0.62 0.60 0.49 0.53 0.51 0.47 -15.5 Non-SSS
35033 Etobicoke South 0.89 0.97 0.79 0.83 0.88 0.69 -14.5 SSS
83126 Toronto Hwy 401 1.62 1.51 1.31 1.43 1.20 1.18 -23.3 SSS
83133 Toronto Island 0.44 0.35 0.37 0.37 0.34 0.33 -22.0 SSS

Notes:

  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

6-year trend for iron in PM2.5

Annual mean (ng/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
29000 Hamilton Downtown 116.6 116.9 105.9 106.9 88.3 104.0 -19.4 SSS
35033 Etobicoke South 110.1 102.5 103.5 91.2 88.1 87.6 -22.7 SSS
83126 Toronto Hwy 401 INS 261.6 275.7 INS 288.6 257.0 1.6 Non-SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

6-year trend for copper in PM2.5

Annual mean (ng/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
29000 Hamilton Downtown 4.7 4.8 4.2 4.0 3.5 4.4 -18.8 SSS
35033 Etobicoke South 5.8 6.1 5.7 5.4 4.3 4.4 -32.1 SSS
83126 Toronto Hwy 401 INS 11.5 11.9 INS 10.2 9.8 -20.6 SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • SSS - Significant Sen's Slope (significant trend detected).

6-year trend for manganese in PM2.5

Annual mean (ng/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
29000 Hamilton Downtown 5.5 3.9 3.5 4.2 2.9 3.4 -41.0 SSS
35033 Etobicoke South 2.8 3.1 2.5 2.4 2.3 2.3 -27.5 SSS
83126 Toronto Hwy 401 INS 3.7 3.7 INS 3.7 3.6 -5.3 Non-SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

6-year trend for lead in PM2.5

Annual mean (ng/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
29000 Hamilton Downtown 3.5 3.6 3.6 3.6 3.3 3.5 -3.2 Non-SSS
35033 Etobicoke South 3.3 4.7 3.1 2.6 2.2 2.8 -29.1 Non-SSS
83126 Toronto Hwy 401 INS 3.5 3.2 INS 2.8 2.9 -11.5 Non-SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

6-year trend for selenium in PM2.5

Annual mean (ng/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
29000 Hamilton Downtown 0.61 0.59 0.67 0.62 0.58 0.68 -3.2 Non-SSS
35033 Etobicoke South 0.61 0.63 0.43 0.49 0.54 0.60 -8.0 Non-SSS
83126 Toronto Hwy 401 INS 0.45 0.43 INS 0.59 0.66 56.2 SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • SSS - Significant Sen's Slope (significant trend detected).
  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

6-year trend for zinc in PM2.5

Annual mean (ng/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
29000 Hamilton Downtown 40.1 25.8 26.5 29.0 20.5 23.9 -33.4 SSS
35033 Etobicoke South 21.6 24.4 18.5 17.7 16.0 15.1 -36.9 SSS
83126 Toronto Hwy 401 INS 24.2 22.3 INS 18.1 19.5 -26.6 SSS

Notes:

  • INS indicates there was insufficient data to calculate a valid annual mean.
  • SSS - Significant Sen's Slope (significant trend detected).

6-year trend for organics in PM2.5

Annual mean (µg/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
83126 Toronto Hwy 401 4.13 7.01 5.20 3.88 4.83 3.94 -22.4 Non-SSS

Notes:

  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

6-year trend for sulphate in PM2.5

Annual mean (µg/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
83126 Toronto Hwy 401 0.91 1.12 0.66 0.65 0.67 0.56 -34.6 SSS

Notes:

  • SSS - Significant Sen's Slope (significant trend detected).

6-year trend for nitrate in PM2.5

Annual mean (µg/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
83126 Toronto Hwy 401 1.31 1.71 1.65 1.20 1.38 1.14 -10.6 Non-SSS

Notes:

  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

6-year trend for ammonium in PM2.5

Annual mean (µg/m3)

ID City/Town 2016 2017 2018 2019 2020 2021 Change over 6 years (%) Trend
83126 Toronto Hwy 401 0.73 1.46 0.65 0.41 1.06 0.89 -3.7 Non-SSS

Notes:

  • Non-SSS - Non-Significant Sen's Slope (significant trend not detected).

Footnotes