The Appendix is intended for use in conjunction with the 2019 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 pollutants are displayed for a 10-year period.

Monitoring network operations

Network description

In 2019, 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 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 2019 ambient air quality monitoring network had 99% 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 Ministry’s Open Data Catalogue web page. 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 or monthly mean for 24-hour VOC samples requires 50% of valid samples.

Network descriptive table

The AQHI network for 2019 is summarized in the 2019 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 2019 Ontario Continuous Ambient Air Monitoring Network also identifies the type of air monitoring site: ambient, road-side, 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 within approximately 100 m of a major roadway with daily traffic volumes greater than 10,000 vehicles per day.

Annual statistics and 10-year trends

The 2019 statistical data and 10-year trends for various continuous pollutants, and selected volatile organic compounds, are provided in 2019 Annual Statistics, and 10-year trends, respectively. 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 10-year 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 10-year 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 and ozone are presented for 2019 (based on a three-year average, 2017-2019) and over a 10-year period in Canadian Ambient Air Quality Standard Reporting. 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 2019 are summarized in AQHI and Air Quality Alert Program Reporting.

2019 air monitoring network

2019 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/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/RS/N Y T T T T N/A N/A
31103 Toronto Downtown* Bay St./Wellesley St. W.  2000 43°39'46.7" -79°23'17.2" 10 A/RS/C/N Y T T T N/A 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 Eighth Line/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
81103 Toronto Downtown* 185 College St., Wallberg Bldg, U OF T 2019 43°39'46.7" -79°23'17.2" 17 A/C/N Y T T T N/A 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

*Toronto Downtown was relocated on two occasions in 2019 and should be counted as one station.

2019 annual statistics

2019 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. 8475 0.1 0.5 1.0 1.8 5.0 34.9 2.68 164.8 64.5
12016 Windsor West College Ave./South St. 8640 0.2 0.3 0.7 1.6 5.2 52.8 3.06 161.2 63.4
13001 Chatham 435 Grand Ave. W. 8747 0.0 0.1 0.4 1.0 3.4 14.8 1.36 75.4 23.5
14111 Sarnia 700 Christina St. N. 8673 0.4 0.6 0.9 1.3 3.1 16.5 1.72 76.0 11.7
15020 Grand Bend Point Blake Conservation Area 8553 0.0 0.1 0.2 0.3 0.6 2.4 0.28 9.2 2.4
15026 London 42 St. Julien St. 8684 0.0 0.1 0.2 0.5 1.7 11.7 0.87 77.0 10.8
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8674 0.0 0.1 0.1 0.3 0.9 3.6 0.39 31.1 4.3
21005 Brantford 324 Grand River Ave. 8659 0.0 0.1 0.2 0.5 1.9 11.3 0.92 49.4 8.0
26060 Kitchener West Ave./Homewood Ave. 8711 0.0 0.2 0.3 0.6 2.0 21.0 1.19 107.6 20.8
27067 St. Catharines Argyle Cres., Pump Stn. 8677 0.0 0.2 0.4 0.7 1.9 16.9 1.16 74.8 10.2
28028 Guelph Exhibition St./Clark St. W. 8692 0.0 0.1 0.2 0.5 1.6 14.6 0.93 68.4 14.0
29000 Hamilton Downtown Elgin St./Kelly St. 8739 0.2 0.5 1.3 2.9 9.7 40.9 3.99 105.6 37.7
29118 Hamilton West Main St. W./Hwy 403 8689 0.3 0.8 1.4 2.8 10.2 43.2 4.15 124.7 33.5
29214 Hamilton Mountain 250 Fennell Ave. W. 8747 0.0 0.2 0.6 1.0 4.2 22.5 1.83 111.0 19.8
31103 Toronto Downtown Bay St./Wellesley St. W. 2783 0.0 0.4 1.0 1.8 4.3 21.4 INS 89.5 17.3
31129 Toronto Downtown 55 John St. 4602 1.4 2.7 4.4 7.9 16.4 50.2 INS 162.4 36.4
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8665 0.2 0.6 1.3 2.6 6.6 42.2 3.42 164.4 33.9
34021 Toronto North 4905 Dufferin St., ECCC 8652 0.0 0.3 0.6 1.5 5.3 36.8 2.70 152.3 38.1
35125 Toronto West 125 Resources Rd. 8583 0.2 1.2 2.8 6.2 17.5 70.9 7.50 278.1 69.8
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8730 0.4 0.7 1.2 2.3 6.5 30.3 2.95 112.9 19.8
44017 Oakville Eighth Line/Glenashton Dr., Halton Res. 8685 0.1 0.2 0.4 0.9 3.9 26.8 1.84 337.4 25.8
44029 Milton 1120 Main St. E. 8575 0.4 1.0 1.2 2.0 6.0 45.8 3.62 163.0 33.6
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8734 0.1 0.3 0.4 0.8 1.6 8.4 0.88 35.8 7.2
46090 Brampton 109 McLaughlin Rd. S. 8662 0.0 0.1 0.2 0.8 4.1 39.5 2.17 147.8 30.2
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8740 0.1 0.2 0.4 0.9 5.5 43.8 2.57 127.0 32.3
47045 Barrie 83 Perry St. 8733 0.0 0.3 0.7 1.6 3.5 29.3 2.18 169.1 24.2
48006 Newmarket Eagle St. W./McCaffrey Rd. 8659 0.2 0.3 0.4 0.7 2.3 18.6 1.31 104.2 13.5
49005 Parry Sound 7 Bay St. 8676 0.1 0.2 0.3 0.5 1.4 6.9 0.72 41.4 5.7
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8712 0.3 0.6 0.8 1.2 2.8 15.8 1.61 70.7 15.1
52023 Kingston 23 Beechgrove Lane 8686 0.0 0.1 0.2 0.5 1.2 5.2 0.55 71.7 11.5
54012 Belleville 2 Sidney St., Water Treatment Plant 8742 0.2 0.2 0.4 0.7 3.0 15.1 1.29 58.1 10.7
56051 Cornwall Bedford St./3rd St. W. 8691 0.2 0.3 0.5 0.8 1.9 24.1 1.52 130.7 21.7
59006 Peterborough 10 Hospital Dr. 8678 0.3 0.6 0.7 1.0 2.0 13.0 1.23 54.0 9.0
63203 Thunder Bay 421 James St. S. 8491 0.6 1.0 1.6 2.6 8.9 35.0 3.79 86.3 20.8
71078 Sault Ste. Marie Sault College 8632 0.2 0.4 0.7 1.3 3.4 11.5 1.48 58.8 14.1
75010 North Bay Chippewa St. W., Dept. National Defence 8717 0.3 0.5 0.7 1.2 3.0 22.6 1.79 99.1 19.5
77233 Sudbury 155 Elm St. 8603 0.3 0.6 1.0 1.8 4.6 37.7 2.77 151.1 37.2
81103 Toronto Downtown Wallberg Building U of T 1191 0.4 0.7 1.2 2.3 6.3 31.7 INS 69.8 16.5

2019 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. 8475 4.0 6.3 8.9 12.2 20.5 38.8 10.94 56.5 34.4 0 0
12016 Windsor West College Ave./South St. 8640 3.1 5.4 8.0 11.2 19.1 40.0 9.98 60.0 32.4 0 0
13001 Chatham 435 Grand Ave. W. 8747 1.9 3.2 4.5 6.4 11.0 25.1 5.84 45.8 28.0 0 0
14111 Sarnia 700 Christina St. N. 8673 0.9 2.6 4.8 8.2 15.4 29.5 6.80 47.2 24.5 0 0
15020 Grand Bend Point Blake Conservation Area 8553 0.3 1.1 1.9 3.0 5.4 10.6 2.49 17.2 11.1 0 0
15026 London 42 St. Julien St. 8684 1.8 3.1 4.3 6.3 11.0 27.2 5.76 45.3 24.9 0 0
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8674 0.8 1.6 2.4 3.5 6.0 11.9 3.02 23.6 9.8 0 0
21005 Brantford 324 Grand River Ave. 8658 2.0 2.9 4.0 6.0 11.1 24.0 5.57 41.5 24.2 0 0
26060 Kitchener West Ave./Homewood Ave. 8711 1.8 2.9 4.4 6.7 12.7 31.7 6.25 57.6 26.1 0 0
27067 St. Catharines Argyle Cres., Pump Stn. 8677 1.8 2.9 4.3 6.5 12.3 27.4 5.97 43.4 21.0 0 0
28028 Guelph Exhibition St./Clark St. W. 8692 1.2 2.4 3.8 6.0 11.7 27.5 5.44 43.7 22.2 0 0
29000 Hamilton Downtown Elgin St./Kelly St. 8737 4.0 6.6 9.9 15.4 24.4 40.0 12.49 58.2 36.5 0 0
29118 Hamilton West Main St. W./Hwy 403 8685 3.5 5.8 8.6 13.4 22.7 38.7 11.29 58.4 38.0 0 0
29214 Hamilton Mountain 250 Fennell Ave. W. 8747 2.1 4.0 6.0 10.0 20.0 36.0 8.81 57.0 35.3 0 0
31103 Toronto Downtown Bay St./Wellesley St. W. 2783 3.9 7.3 10.8 15.3 25.1 45.3 INS 53.0 31.0 0 0
31129 Toronto Downtown 55 John St. 4602 6.1 9.3 12.6 16.7 25.0 37.9 INS 66.9 32.3 0 0
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8664 2.6 4.9 7.5 11.8 21.6 42.6 10.24 78.3 33.7 0 0
34021 Toronto North 4905 Dufferin St., ECCC 8649 2.8 4.8 7.5 12.1 22.2 42.7 10.51 70.1 33.4 0 0
35125 Toronto West 125 Resources Rd. 8583 4.5 8.3 12.3 17.6 28.0 47.1 14.62 75.9 38.7 0 0
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8728 2.4 4.6 7.1 11.2 20.7 37.2 9.61 53.2 31.3 0 0
44017 Oakville Eighth Line/Glenashton Dr., Halton Res. 8684 2.4 4.1 6.5 10.4 19.4 38.8 9.08 58.1 33.9 0 0
44029 Milton 1120 Main St. E. 8569 2.0 4.0 6.0 9.8 20.2 39.0 8.86 57.0 32.9 0 0
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8734 0.7 1.3 2.2 3.8 8.0 17.4 3.50 38.9 16.4 0 0
46090 Brampton 109 McLaughlin Rd. S. 8662 1.6 3.1 5.6 9.8 20.1 40.0 8.59 62.3 35.7 0 0
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8737 2.1 3.7 6.0 9.8 17.6 37.3 8.40 52.3 30.6 0 0
47045 Barrie 83 Perry St. 8733 1.7 2.8 4.0 6.7 14.0 32.8 6.34 56.0 25.2 0 0
48006 Newmarket Eagle St. W./McCaffrey Rd. 8659 1.0 2.0 3.3 5.7 12.5 33.3 5.47 55.0 26.1 0 0
49005 Parry Sound 7 Bay St. 8676 0.6 1.0 1.5 2.5 5.5 18.9 2.64 34.8 12.5 0 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8712 1.6 2.8 4.4 7.4 14.7 32.5 6.70 51.2 26.9 0 0
52023 Kingston 23 Beechgrove Lane 8683 1.1 1.8 2.6 4.1 8.5 22.0 4.01 50.3 19.6 0 0
54012 Belleville 2 Sidney St., Water Treatment Plant 8743 1.1 1.8 2.7 4.4 9.2 24.2 4.24 41.4 17.2 0 0
56051 Cornwall Bedford St./3rd St. W. 8691 1.2 2.0 3.1 5.1 10.8 30.2 5.03 49.4 28.3 0 0
59006 Peterborough 10 Hospital Dr. 8678 0.6 1.4 2.4 4.0 8.5 25.4 3.90 43.3 18.2 0 0
63203 Thunder Bay 421 James St. S. 8491 1.7 2.9 4.4 7.2 14.6 31.6 6.65 49.2 25.2 0 0
71078 Sault Ste. Marie Sault College 8632 1.1 1.8 2.8 4.7 10.3 22.6 4.47 46.8 20.8 0 0
75010 North Bay Chippewa St. W., Dept. National Defence 8717 1.0 1.6 2.6 4.6 11.7 36.6 5.11 53.8 27.0 0 0
77233 Sudbury 155 Elm St. 8603 1.6 2.7 4.2 6.8 15.3 41.4 6.88 56.8 29.5 0 0
81103 Toronto Downtown Wallberg Building U of T 1191 3.2 5.1 7.4 10.2 18.1 32.7 INS 37.1 22.2 0 0

2019 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. 8475 4.5 7.3 10.2 14.2 25.6 67.4 13.6 200.4 93.8
12016 Windsor West College Ave./South St. 8640 3.6 6.2 8.9 13.0 23.7 86.8 13.0 211.2 90.8
13001 Chatham 435 Grand Ave. W. 8747 2.0 3.5 5.2 7.7 13.9 34.2 7.2 117.1 47.6
14111 Sarnia 700 Christina St. N. 8673 1.5 3.4 5.8 9.7 18.4 42.4 8.5 120.0 33.8
15020 Grand Bend Point Blake Conservation Area 8553 0.3 1.1 2.0 3.2 5.9 12.1 2.7 23.1 12.6
15026 London 42 St. Julien St. 8684 2.0 3.4 4.8 6.9 12.6 37.3 6.6 116.7 35.6
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8674 0.9 1.7 2.6 3.8 6.7 15.5 3.4 51.7 12.1
21005 Brantford 324 Grand River Ave. 8659 2.2 3.1 4.4 6.7 13.4 31.6 6.5 74.8 28.9
26060 Kitchener West Ave./Homewood Ave. 8711 2.0 3.2 4.8 7.5 14.6 47.1 7.4 157.6 45.8
27067 St. Catharines Argyle Cres., Pump Stn. 8677 2.1 3.3 4.7 7.2 14.5 40.1 7.1 111.4 28.3
28028 Guelph Exhibition St./Clark St. W. 8692 1.5 2.6 4.1 6.5 13.2 38.7 6.4 108.1 36.0
29000 Hamilton Downtown Elgin St./Kelly St. 8739 4.4 7.6 11.6 18.3 34.7 75.3 16.5 156.5 71.8
29118 Hamilton West Main St. W./Hwy 403 8686 4.2 7.0 10.3 16.7 32.5 76.1 15.4 167.1 71.5
29214 Hamilton Mountain 250 Fennell Ave. W. 8747 2.4 4.2 7.0 11.3 24.0 52.9 10.7 164.0 55.1
31103 Toronto Downtown Bay St./Wellesley St. W. 2783 4.0 8.2 12.1 17.2 28.8 64.6 INS 140.2 47.7
31129 Toronto Downtown 55 John St. 4602 8.1 12.7 17.8 24.5 39.1 85.3 INS 229.3 68.7
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8665 3.1 6.0 9.2 14.3 27.4 78.2 13.7 228.0 63.6
34021 Toronto North 4905 Dufferin St., ECCC 8652 3.3 5.5 8.6 13.8 28.1 72.7 13.2 214.3 70.0
35125 Toronto West 125 Resources Rd. 8583 5.5 10.5 15.9 23.6 45.1 109.5 22.1 353.9 106.0
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8730 3.0 5.6 8.7 13.6 26.2 62.5 12.6 161.7 49.3
44017 Oakville Eighth Line/Glenashton Dr., Halton Res. 8685 2.7 4.5 7.1 11.5 22.9 62.3 10.9 386.9 59.6
44029 Milton 1120 Main St. E. 8575 3.0 5.0 7.6 12.0 27.0 79.6 12.5 217.0 65.1
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8734 1.0 1.8 2.8 4.6 9.6 23.2 4.4 61.3 22.6
46090 Brampton 109 McLaughlin Rd. S. 8662 1.8 3.3 6 10.9 24.1 75.4 10.74 206.1 65.8
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8740 2.5 4.2 6.6 11 23.4 75.1 10.97 177.8 62.9
47045 Barrie 83 Perry St. 8733 2 3.4 5 7.8 18 56.3 8.52 207.8 45.0
48006 Newmarket Eagle St. W./McCaffrey Rd. 8659 1.3 2.4 3.9 6.6 14.8 49.0 6.78 126.5 35.7
49005 Parry Sound 7 Bay St. 8676 0.8 1.4 2 3.1 6.7 23.4 3.34 58.5 17.2
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8712 2.2 3.6 5.4 8.7 17.2 46.5 8.31 102.3 42.0
52023 Kingston 23 Beechgrove Lane 8686 1.1 1.9 2.9 4.6 9.4 26.9 4.55 122.0 31.0
54012 Belleville 2 Sidney St., Water Treatment Plant 8742 1.4 2.1 3.2 5.4 11.7 36.5 5.53 83.1 21.4
56051 Cornwall Bedford St./3rd St. W. 8691 1.5 2.5 3.7 6 12.9 51.8 6.54 170.7 41.9
59006 Peterborough 10 Hospital Dr. 8678 1.2 2 3.1 5 10.5 34.8 5.14 91.1 25.0
63203 Thunder Bay 421 James St. S. 8491 2.7 4.2 6.3 10.3 22.9 59.9 10.44 123.6 44.5
71078 Sault Ste. Marie Sault College 8632 1.5 2.4 3.6 6 13.7 31.1 5.95 105.4 34.8
75010 North Bay Chippewa St. W., Dept. National Defence 8717 1.3 2.2 3.5 5.9 14.5 55.9 6.91 145.3 46.5
77233 Sudbury 155 Elm St. 8603 2.1 3.5 5.4 8.7 19.8 75.5 9.65 187.8 66.6
81103 Toronto Downtown Wallberg Building U of T 1191 3.9 6.3 8.8 12.9 23.7 58.8 INS 105.8 38.6

2019 fine particulate matter (PM2.5) annual statistics

Unit: micrograms per cubic metre (μg/m3)
PM2.5 24h reference level: 28 μg/m3

ID City Location Valid h 10% 30% 50% 70% 90% 99% Mean Max 1h Max 24h Number of times above 24h reference level
12008 Windsor Downtown 467 University Ave. W. 8488 3 4 6 9 15 28 7.8 48 27 0
12016 Windsor West College Ave./South St. 8620 3 5 8 11 17 32 9.1 54 38 3
13001 Chatham 435 Grand Ave. W. 8718 2 3 5 9 14 24 6.8 41 27 0
14111 Sarnia 700 Christina St. N. 8719 1 3 5 9 16 28 7.1 57 31 1
15020 Grand Bend Point Blake Conservation Area 8541 2 2 4 6 11 20 5.4 40 23 0
15026 London 42 St. Julien St. 8746 2 3 5 8 14 26 6.7 55 26 0
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8697 1 3 5 8 14 25 6.7 42 22 0
18007 Tiverton 4th Concession/Bruce Rd. 23 8640 1 2 4 6 11 21 5.0 42 21 0
21005 Brantford 324 Grand River Ave. 8729 2 4 6 9 15 29 7.4 91 28 0
26060 Kitchener West Ave./Homewood Ave. 8725 2 3 6 8 15 28 7.2 56 31 1
27067 St. Catharines Argyle Cres., Pump Stn. 8625 2 3.9 5 8 14 26 7.0 50 25 0
28028 Guelph Exhibition St./Clark St. W. 8723 1 3 5 9 16 29 7.1 55 29 1
29000 Hamilton Downtown Elgin St./Kelly St. 8646 2 5 7 11 18 30 8.8 67 29 2
29118 Hamilton West Main St. W./Hwy 403 8726 2 4 6 9 16 28 7.8 50 26 0
29214 Hamilton Mountain 250 Fennell Ave. W. 8678 2 4 6 9 16 31 7.9 61 28 0
31103 Toronto Downtown Bay St./Wellesley St. W. 2852 2 4 6 9 16 28 INS 55 29 1
31129 Toronto Downtown 55 John St. 4582 3 5 7 9 15 29 INS 44 25 0
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8748 2 4 6 8 14 26 7.0 51 31 1
34021 Toronto North 4905 Dufferin St., ECCC 8626 1 3 5 8 14 28 6.8 52 32 1
35125 Toronto West 125 Resources Rd. 8688 2 4 6 8 14 25 7.2 72 25 0
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8730 2 3 6 8 15 25 7.0 55 29 1
44017 Oakville Eighth Line/Glenashton Dr., Halton Res. 8621 2 4 6 9 14 26 7.2 52 28 0
44029 Milton 1120 Main St. E. 8530 2 4 6 9 15 27 7.5 44 27 0
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8667 2 3 5 7 12 26 6.1 55 28 0
46090 Brampton 109 McLaughlin Rd. S. 8720 2 3 5 8 14 26 6.8 47 26 0
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8697 1 3 5 9 15 26 7.0 47 29 1
47045 Barrie 83 Perry St. 8510 2 3 5 9 16 30 7.5 51 34 2
48006 Newmarket Eagle St. W./McCaffrey Rd. 8682 1 2 4 7 13 25 5.9 43 26 0
49005 Parry Sound 7 Bay St. 8612 1 2 3 5 9 21 4.4 51 21 0
49010 Dorset 1026 Bellwood Acres Rd. 8689 1 2 3 5 9 18 4.1 34 20 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8517 2 3 5 7 12 23 5.9 39 29 1
51010 Petawawa Petawawa Research Forest Facility 8623 1 2 3 5 7 14 3.8 29 14 0
52023 Kingston 23 Beechgrove Lane 8735 1 3 4 6 11 22 5.4 59 26 0
54012 Belleville 2 Sidney St., Water Treatment Plant 8586 2 3 4 7 13 25 6.1 45 31 1
56051 Cornwall Bedford St./3rd St. W. 8702 2 3 5 7 11 23 5.9 67 25 0
59006 Peterborough 10 Hospital Dr. 8730 1 3 4 7 13 25 6.0 48 28 0
63203 Thunder Bay 421 James St. S. 8702 1 3 4 6 10 22 5.1 70 24 0
71078 Sault Ste. Marie Sault College 8652 1 2 4 5 10 20 4.8 55 19 0
75010 North Bay Chippewa St. W., Dept. National Defence 8711 1 2 4 5 9 17 4.5 59 19 0
77233 Sudbury 155 Elm St. 8706 1 2 4 6 10 22 5.0 75 22 0
81103 Toronto Downtown Wallberg Building U of T 1236 1 3 5 8 15 26 INS 46 18 0

Notes

  • Measurements taken by SHARP 5030.
  • The PM2.5 24-hour reference level of 28 µg/m3 is based on the 24-hour PM2.5 Canadian Ambient Air Quality Standard (CAAQS) established in 2015.

2019 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. 8512 11 20 26 32 42 60 26.6 82 55 1
12016 Windsor West College Ave./South St. 8635 10 20 27 34 44 61 27.3 80 49 0
13001 Chatham 435 Grand Ave. W. 8724 14 23 29 35 44 59 29.2 76 53 0
14111 Sarnia 700 Christina St. N. 8675 14 23 29 36 45 62 29.2 87 56 4
15020 Grand Bend Point Blake Conservation Area 8528 17 26 32 37 45 60 31.6 85 53 7
15026 London 42 St. Julien St. 8694 9 21 27 33 43 55.1 26.8 70 49 0
16015 Port Stanley 43665 Dexter Line, Elgin Water T. Plt 8666 17 26 32 38 48 61 32.3 77 56 0
18007 Tiverton 4th Concession/Bruce Rd. 23 8694 18 25 31 37 43 56 31.1 81 54 1
21005 Brantford 324 Grand River Ave. 8680 10 21 28 34 44 56 27.5 74 49 0
26060 Kitchener West Ave./Homewood Ave. 8697 11 21 27 33 43 55 27.2 77 47 0
27067 St. Catharines Argyle Cres., Pump Stn. 8704 12 23 29 35 43 56 28.4 70 48 0
28028 Guelph Exhibition St./Clark St. W. 8690 11 21 27 33 41 53 26.3 74 47 0
29000 Hamilton Downtown Elgin St./Kelly St. 8677 7 18 24 31 40 53.3 24.4 65 47 0
29118 Hamilton West Main St. W./Hwy 403 8689 4 17 24 31 40 52 23.6 65 46 0
29214 Hamilton Mountain 250 Fennell Ave. W. 8747 12 21 27 33 43 56 27.5 70 51 0
31103 Toronto Downtown Bay St./Wellesley St. W. 2827 13 22 28 34 40 49 INS INS INS 0
31129 Toronto Downtown 55 John St. 4589 7 15 20 25 37 55 INS 76 46 0
33003 Toronto East Kennedy Rd./Lawrence Ave. E. 8667 9 19 25 31 39 51 24.6 67 47 0
34021 Toronto North 4905 Dufferin St., ECCC 8585 7 17 24 31 40 53 24.1 77 43 0
35125 Toronto West 125 Resources Rd. 8463 4 15 22 28 38 55 21.8 77 44 0
44008 Burlington North Shore Blvd. E./Lakeshore Rd. 8694 9 20 27 34 42 56 26.6 74 47 0
44017 Oakville Eighth Line/Glenashton Dr., Halton Res. 8685 11 21 27 33 42 56 27.1 71 50 0
44029 Milton 1120 Main St. E. 8573 8 21 27 34 43 58 26.9 77 50 0
45027 Oshawa Brittania Ave. W., EP Taylor Stables 8706 9 20 25 30 37 51 24.4 66 40 0
46090 Brampton 109 McLaughlin Rd. S. 8611 9 20 27 33 42 55 26.5 72 49 0
46108 Mississauga 3359 Mississauga Rd. N., U of T Campus 8717 5 18 25 32 40.5 53 24.5 65 48 0
47045 Barrie 83 Perry St. 8712 9 20 26 33 40 51 25.7 75 47 0
48006 Newmarket Eagle St. W./McCaffrey Rd. 8642 13 22 28 34 41 54 27.8 88 48 4
49005 Parry Sound 7 Bay St. 8682 16 25 30 36 43 54 29.8 68 48 0
49010 Dorset 1026 Bellwood Acres Rd. 8671 10 22 28 35 42 52 27.5 64 47 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8725 11 20 26 32 39 49 25.9 57 46 0
51010 Petawawa Petawawa Research Forest Facility 8746 12 22 28 34 41 49 27.3 58 47 0
52023 Kingston 23 Beechgrove Lane 8680 16 25 30 35 43 55 29.9 68 51 0
54012 Belleville 2 Sidney St., Water Treatment Plant 8743 15 24 30 35 43 56 29.6 73 51 0
56051 Cornwall Bedford St./3rd St. W. 8686 12 22 28 33 40 50 26.9 58 46 0
59006 Peterborough 10 Hospital Dr. 8684 14 23 28 34 42 53 28.3 68 48 0
63203 Thunder Bay 421 James St. S. 8695 8 18 24 30 37 48 23.7 56 47 0
71078 Sault Ste. Marie Sault College 8652 15 23 28 34 41 51 28.1 61 50 0
75010 North Bay Chippewa St. W., Dept. National Defence 8722 11 21 27 32 40 50 26.4 63 46 0
77233 Sudbury 155 Elm St. 8607 12 21 27 32 39 49 26.3 75 46 0
81103 Toronto Downtown Wallberg Building U of T 1191 14 25 31 36 43 54 INS 64 44 0

2019 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 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. 8514 0.0 0.0 0.1 0.2 1.0 6.2 0.44 21.8 6.7 0 0 0
12016 Windsor West College Ave./South St. 8042 0.0 0.1 0.3 0.6 1.9 8.4 0.82 31.7 7.9 0 0 0
14111 Sarnia 700 Christina St. N. 8697 0.0 0.1 0.3 0.6 3.7 32.7 1.93 69.4 30.2 37 47 0
29000 Hamilton Downtown Elgin St./Kelly St. 8706 0.2 0.4 0.7 2.0 15.4 52.1 4.75 123.7 45.9 269 185 1
29214 Hamilton Mountain 250 Fennell Ave. W. 8532 0.1 0.3 0.5 1.7 10.2 40.4 3.47 68.7 42.1 40 88 0
34021 Toronto North 4905 Dufferin St., ECCC 8617 0.0 0.0 0.0 0.1 0.3 2.0 0.15 8.6 1.6 0 0 0
35125 Toronto West 125 Resources Rd. 8458 0.0 0.1 0.1 0.2 0.5 2.5 0.27 11.8 2.3 0 0 0
44029 Milton 1120 Main St. E. 4654 0.5 0.7 0.9 1.0 2.0 5.6 INS 14.9 3.7 0 0 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8733 0.1 0.1 0.1 0.2 0.3 0.7 0.17 2.7 0.6 0 0 0
71078 Sault Ste. Marie Sault College 8607 0.0 0.1 0.1 0.2 0.8 14.4 0.70 52.0 10.9 7 6 0
77233 Sudbury 155 Elm St. 8596 0.1 0.1 0.2 0.5 2.7 15.6 1.15 93.8 8.3 18 6 0

2019 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. 8195 0.16 0.18 0.21 0.24 0.34 0.70 0.24 2.33 1.328 0 0
29000 Hamilton Downtown Elgin St./Kelly St. 8616 0.14 0.17 0.21 0.27 0.41 0.69 0.25 1.89 0.95 0 0
34021 Toronto North 4905 Dufferin St., ECCC 8493 0.14 0.16 0.19 0.22 0.30 0.47 0.20 1.03 0.71 0 0
35125 Toronto West 125 Resources Rd. 8506 0.16 0.19 0.22 0.26 0.35 0.62 0.24 1.49 0.89 0 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 8688 0.12 0.15 0.17 0.20 0.25 0.41 0.18 0.68 0.54 0 0

2019 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. 8604 0 0 0 0 0 2 0.09 8 1
14111 Sarnia 700 Christina St. N. 8694 0 0 0 0 0 1 0.04 2 1
29000 Hamilton Downtown Elgin St./Kelly St. 8738 0 0 0 0 0 1 0.06 9 1
71078 Sault Ste. Marie Sault College 8559 0 0 0 0 1 1 0.28 5 1

2019 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 Location 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 College Ave./South St. 54 0.265 0.315 0.380 0.505 0.672 1.586 0.223 0.445 0.217 0 0
14111 Sarnia 700 Christina St. 57 0.100 0.242 0.335 0.545 0.739 2.047 0.100 0.419 0.319 0 0
15026 London 42 St. Julien St. 54 0.100 0.218 0.292 0.376 0.450 0.578 0.100 0.296 0.118 0 0
26060 Kitchener West Ave./Homewood Ave. 57 0.100 0.212 0.291 0.380 0.461 0.692 0.100 0.290 0.147 0 0
29000 Hamilton Downtown Elgin St./Kelly St. 59 0.222 0.316 0.411 0.657 1.129 2.070 0.100 0.568 0.427 0 1
34021 Toronto North 4905 Dufferin St., ECCC 50 0.100 0.231 0.333 0.405 0.602 0.935 0.100 0.341 0.189 0 0
48006 Newmarket Eagle St. W./McCaffrey Rd. 55 0.100 0.100 0.229 0.318 0.424 0.693 0.100 0.250 0.146 0 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 49 0.100 0.209 0.264 0.399 0.542 1.017 0.100 0.323 0.205 0 0

2019 toluene annual statistics

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

ID City Location Number of samples 10% 25% 50% 75% 90% Max Min Mean Standard deviation Number of times above 24h criteria
12016 Windsor West College Ave./South St. 54 0.304 0.415 0.648 0.998 1.489 2.184 0.223 0.797 0.487 0
14111 Sarnia 700 Christina St. 57 0.100 0.243 0.542 0.931 1.638 6.652 0.100 0.779 0.996 0
15026 London 42 St. Julien St. 54 0.100 0.245 0.412 0.695 0.891 1.747 0.100 0.491 0.340 0
26060 Kitchener West Ave./Homewood Ave. 57 0.100 0.307 0.433 0.618 1.019 4.530 0.100 0.572 0.626 0
29000 Hamilton Downtown Elgin St./Kelly St. 59 0.279 0.361 0.624 1.031 1.581 3.573 0.100 0.817 0.676 0
34021 Toronto North 4905 Dufferin St., ECCC 50 0.487 0.677 1.065 1.586 2.780 6.942 0.100 1.390 1.183 0
48006 Newmarket Eagle St. W./McCaffrey Rd. 55 0.100 0.100 0.252 0.476 0.779 2.731 0.100 0.418 0.471 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 49 0.274 0.369 0.550 0.798 1.047 1.571 0.100 0.618 0.337 0

2019 ethylbenzene annual statistics

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

ID City Location Number of sample 10% 25% 50% 75% 90% Max Min Mean Standard deviation Number of times above 24h criteria
12016 Windsor West College Ave./South St. 54 0.040 0.050 0.121 0.174 0.222 0.589 0.040 0.137 0.106 0
14111 Sarnia 700 Christina St. 57 0.040 0.040 0.086 0.140 0.259 0.647 0.040 0.118 0.122 0
15026 London 42 St. Julien St. 54 0.040 0.040 0.040 0.094 0.117 0.251 0.040 0.070 0.049 0
26060 Kitchener West Ave./Homewood Ave. 57 0.040 0.040 0.040 0.102 0.156 0.238 0.040 0.079 0.053 0
29000 Hamilton Downtown Elgin St./Kelly St. 59 0.040 0.040 0.096 0.162 0.284 0.557 0.040 0.126 0.113 0
34021 Toronto North 4905 Dufferin St., ECCC 50 0.040 0.084 0.110 0.209 0.302 0.717 0.040 0.157 0.131 0
48006 Newmarket Eagle St. W./McCaffrey Rd. 55 0.040 0.040 0.040 0.065 0.113 0.368 0.040 0.067 0.062 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 49 0.040 0.040 0.040 0.083 0.139 0.202 0.040 0.064 0.043 0

2019 m- and p-xylene annual statistics

Unit: micrograms per cubic metre (μg/m3)

ID City Location Number of sample 10% 25% 50% 75% 90% Max Min Mean Standard deviation
12016 Windsor West College Ave./South St. 54 0.100 0.100 0.305 0.494 0.785 2.302 0.100 0.409 0.386
14111 Sarnia 700 Christina St. 57 0.100 0.100 0.202 0.300 0.533 1.114 0.100 0.256 0.224
15026 London 42 St. Julien St. 54 0.100 0.100 0.100 0.243 0.368 0.832 0.100 0.200 0.170
26060 Kitchener West Ave./Homewood Ave. 57 0.100 0.100 0.100 0.273 0.431 0.775 0.100 0.223 0.174
29000 Hamilton Downtown Elgin St./Kelly St. 59 0.100 0.100 0.247 0.529 0.883 1.841 0.100 0.398 0.406
34021 Toronto North 4905 Dufferin St., ECCC 50 0.100 0.229 0.317 0.651 1.012 2.098 0.100 0.500 0.446
48006 Newmarket Eagle St. W./McCaffrey Rd. 55 0.100 0.100 0.100 0.218 0.376 1.068 0.100 0.191 0.198
51001 Ottawa Downtown Rideau St./Wurtemburg St. 49 0.100 0.100 0.100 0.244 0.362 0.676 0.100 0.186 0.132

2019 o-xylene annual statistics

Unit: micrograms per cubic metre (μg/m3)

ID City Location Number of sample 10% 25% 50% 75% 90% Max Min Mean Standard deviation
12016 Windsor West College Ave./South St. 54 0.045 0.045 0.115 0.191 0.272 0.564 0.045 0.147 0.118
14111 Sarnia 700 Christina St. 57 0.045 0.045 0.045 0.119 0.200 0.414 0.045 0.101 0.085
15026 London 42 St. Julien St. 54 0.045 0.045 0.045 0.085 0.145 0.304 0.045 0.074 0.057
26060 Kitchener West Ave./Homewood Ave. 57 0.045 0.045 0.045 0.101 0.147 0.302 0.045 0.083 0.061
29000 Hamilton Downtown Elgin St./Kelly St. 59 0.045 0.045 0.101 0.187 0.310 0.814 0.045 0.145 0.149
34021 Toronto North 4905 Dufferin St., ECCC 50 0.045 0.045 0.109 0.197 0.320 0.680 0.045 0.156 0.143
48006 Newmarket Eagle St. W./McCaffrey Rd. 55 0.045 0.045 0.045 0.045 0.127 0.315 0.045 0.068 0.057
51001 Ottawa Downtown Rideau St./Wurtemburg St. 49 0.045 0.045 0.045 0.106 0.141 0.279 0.045 0.078 0.052

2019 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 Location Number of sample 10% 25% 50% 75% 90% Max Min Mean Standard deviation Number of times above annual criteria
24-hour		 Number of times above annual criteria
1 year
12016 Windsor West College Ave./South St. 54 0.025 0.025 0.025 0.025 0.025 0.090 0.025 0.028 0.013 0 0
14111 Sarnia 700 Christina St. 57 0.025 0.025 0.025 0.025 0.084 0.608 0.025 0.054 0.093 0 0
15026 London 42 St. Julien St. 54 0.025 0.025 0.025 0.025 0.025 0.025 0.025 0.025 0.000 0 0
26060 Kitchener West Ave./Homewood Ave. 57 0.025 0.025 0.025 0.025 0.025 0.025 0.025 0.025 0.000 0 0
29000 Hamilton Downtown Elgin St./Kelly St. 59 0.025 0.025 0.025 0.025 0.025 0.062 0.025 0.028 0.009 0 0
34021 Toronto North 4905 Dufferin St., ECCC 50 0.025 0.025 0.025 0.025 0.025 0.054 0.025 0.026 0.004 0 0
48006 Newmarket Eagle St. W./McCaffrey Rd. 55 0.025 0.025 0.025 0.025 0.025 0.025 0.025 0.025 0.000 0 0
51001 Ottawa Downtown Rideau St./Wurtemburg St. 49 0.025 0.025 0.025 0.025 0.025 0.079 0.025 0.027 0.010 0 0

10-year trends

10-year trend for nitric oxide (NO)

Annual mean (ppb)

ID City/Town 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 4.7 4.5 4.7 3.7 4.0 3.5 3.1 3.3 3.2 2.7 -23.9 SSS
12016 Windsor West 6.1 3.8 4.6 3.6 3.8 4.2 2.9 2.6 2.6 3.1 -23.2 SSS
13001 Chatham 2.6 1.9 1.8 1.6 1.5 1.7 1.4 1.9 1.8 1.4 -12.0 SSS
14111 Sarnia 2.2 3.1 2.1 1.7 1.9 2.4 INS 1.5 1.8 1.7 -18.7 SSS
15020 Grand Bend N/A 0.3 0.3 1.0 0.2 0.3 0.5 0.3 0.2 0.3 -9.3 Non-SSS
15026 London 2.9 3.3 4.2 1.4 1.3 1.4 1.0 1.0 0.8 0.9 -62.5 SSS
21005 Brantford 1.3 1.2 1.1 1.2 0.9 1.3 0.8 0.8 1.0 0.9 -8.7 Non-SSS
26060 Kitchener 2.5 2.0 2.1 1.6 1.6 1.6 1.3 1.0 0.9 1.2 -19.3 SSS
27067 St. Catharines 2.8 2.3 2.5 2.2 1.7 2.1 1.5 1.2 0.9 1.2 -44.9 SSS
28028 Guelph 2.0 2.3 2.2 1.1 1.2 1.3 1.1 1.1 1.2 0.9 -47.6 SSS
29000 Hamilton Downtown 5.0 4.8 4.6 4.3 3.9 1.3 4.2 3.9 3.9 4.0 -9.6 Non-SSS
29118 Hamilton West N/A 6.4 6.3 5.4 5.9 5.1 6.2 3.9 4.2 4.2 -24.2 SSS
29214 Hamilton Mountain 2.2 2.3 1.9 2.0 2.0 1.8 1.2 1.2 1.2 1.8 -32.0 SSS
33003 Toronto East 7.8 7.6 6.6 5.7 6.2 5.8 5.4 4.4 3.1 3.4 -45.2 SSS
34021 Toronto North 5.7 6.2 5.0 4.1 4.3 3.9 3.5 3.0 2.5 2.7 -50.3 SSS
35125 Toronto West 13.4 12.4 11.3 8.6 9.5 9.2 8.2 7.7 6.7 7.5 -33.0 SSS
44008 Burlington 5.0 4.6 4.6 4.6 4.6 3.9 3.9 3.4 2.7 3.0 -35.9 SSS
44017 Oakville 3.6 2.7 3.4 2.1 3.4 2.7 1.8 1.7 1.8 1.8 -31.2 SSS
45027 Oshawa 2.3 2.3 2.1 1.5 2.0 2.3 2.5 2.4 0.9 0.9 -23.5 SSS
46090 Brampton 3.7 4.6 4.4 4.6 4.0 3.8 3.4 2.2 2.2 2.2 -45.8 SSS
46108 Mississauga 4.1 4.1 3.8 3.1 2.9 3.1 3.6 2.0 1.6 2.6 -33.5 SSS
47045 Barrie 4.3 3.8 3.2 3.2 3.7 3.5 3.7 2.6 1.8 2.2 -32.4 SSS
48006 Newmarket 2.3 2.2 2.0 1.5 1.4 1.7 1.6 1.4 1.3 1.3 -28.4 SSS
49005 Parry Sound N/A 0.9 0.5 0.5 0.6 0.8 0.6 0.5 0.5 0.7 -1.6 Non-SSS
51001 Ottawa Downtown 1.6 1.8 2.4 2.1 1.9 2.0 1.7 1.5 1.7 1.6 -3.8 Non-SSS
52023 Kingston 0.3 0.5 0.4 0.2 0.8 0.9 0.7 0.6 0.6 0.6 44.4 SSS
54012 Belleville 2.3 2.3 1.6 1.7 1.2 1.5 1.8 1.1 1.0 1.3 -34.6 SSS
56051 Cornwall 2.0 1.9 2.2 1.9 1.5 1.8 2.1 1.2 1.4 1.5 -7.3 Non-SSS
59006 Peterborough 1.7 2.2 1.8 1.7 1.8 1.5 1.3 1.2 0.9 1.2 -47.7 SSS
63203 Thunder Bay 4.6 5.9 5.1 4.7 4.2 5.2 3.8 4.1 3.8 3.8 -22.7 SSS
71078 Sault Ste. Marie 1.9 2.0 1.7 1.3 2.0 1.7 1.0 1.3 1.2 1.5 -35.2 SSS
75010 North Bay 3.4 4.0 2.9 2.5 2.6 2.1 2.0 1.6 1.7 1.8 -53.4 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 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).
  • N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for nitrogen dioxide (NO2)

Annual mean (ppb)

ID City/Town 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 15.6 14.5 13.2 12.4 14.0 12.7 11.4 11.1 11.0 10.9 -24.2 SSS
12016 Windsor West 14.5 12.9 11.4 11.5 11.8 11.4 10.6 9.9 8.8 10.0 -28.5 SSS
13001 Chatham 6.4 6.6 5.7 6.0 6.8 6.8 5.4 6.1 5.1 5.8 -12.0 Non-SSS
14111 Sarnia 8.0 8.6 8.6 8.1 9.0 9.3 INS 7.3 7.6 6.8 -16.8 SSS
15020 Grand Bend N/A 3.6 3.6 4.4 3.1 3.4 2.8 3.0 3.3 2.5 -24.2 SSS
15026 London 8.8 8.3 6.3 6.4 6.9 6.6 5.4 5.8 5.4 5.8 -25.6 SSS
21005 Brantford 5.8 6.1 5.4 4.8 5.5 5.5 4.8 4.4 5.2 5.6 -7.0 SSS
26060 Kitchener 7.7 7.7 7.1 6.7 7.0 6.8 6.2 5.8 5.8 6.3 -19.7 SSS
27067 St. Catharines 9.1 8.5 8.1 7.7 7.3 7.3 6.6 6.6 6.0 6.0 -31.7 SSS
28028 Guelph 6.7 7.3 6.5 6.6 7.1 6.3 6.2 5.9 5.9 5.4 -19.3 SSS
29000 Hamilton Downtown 12.7 13.5 11.9 12.4 12.4 12.2 11.9 11.9 11.6 12.5 -5.8 Non-SSS
29118 Hamilton West N/A 13.1 12.1 12.7 12.8 12.2 11.8 10.4 11.0 11.3 -12.9 SSS
29214 Hamilton Mountain 8.9 9.9 8.6 9.0 9.3 9.0 7.9 7.8 7.8 8.8 -12.9 SSS
33003 Toronto East 14.8 15.2 14.0 13.6 14.2 13.9 12.1 11.5 10.6 10.2 -32.8 SSS
34021 Toronto North 14.3 15.4 13.4 12.9 13.4 12.9 12.0 10.5 10.4 10.5 -32.4 SSS
35125 Toronto West 20.1 19.1 16.3 16.1 17.1 16.6 15.7 15.0 14.4 14.6 -25.3 SSS
44008 Burlington 12.2 11.8 11.0 11.0 10.9 10.4 10.2 9.7 9.4 9.6 -19.7 SSS
44017 Oakville 9.2 10.3 9.1 9.2 8.2 7.5 8.2 8.2 8.5 9.1 -14.3 SSS
45027 Oshawa 7.2 7.0 5.6 5.9 6.8 6.6 6.3 6.4 3.8 3.5 -33.9 SSS
46090 Brampton 10.7 11.3 10.4 9.1 10.6 9.9 9.7 8.3 8.1 8.6 -26.4 SSS
46108 Mississauga 10.4 10.6 9.6 9.5 9.2 9.2 8.6 8.0 7.2 8.4 -25.1 SSS
47045 Barrie 8.7 8.6 8.1 7.8 8.1 7.4 8.1 7.3 6.4 6.3 -23.1 SSS
48006 Newmarket 7.2 8.1 7.2 6.8 6.8 6.8 6.5 6.3 6.1 5.5 -23.7 SSS
49005 Parry Sound N/A 3.6 3.3 2.9 3.3 3.2 2.9 2.7 2.9 2.6 -24.4 SSS
51001 Ottawa Downtown 7.4 7.9 7.8 7.9 7.4 7.4 6.9 7.1 7.3 6.7 -14.2 SSS
52023 Kingston 4.3 4.6 4.0 3.6 3.9 4.4 4.4 4.4 4.2 4.0 -9.0 SSS
54012 Belleville 5.5 6.3 4.7 4.7 4.5 4.8 5.1 4.3 3.7 4.2 -22.7 SSS
56051 Cornwall 6.5 6.5 6.1 6.2 5.6 5.3 5.5 5.0 5.1 5.0 -20.9 SSS
59006 Peterborough 5.0 4.3 3.7 5.0 5.3 5.1 4.5 4.7 4.5 3.9 -18.9 SSS
63203 Thunder Bay 7.8 8.6 7.3 7.3 7.8 7.5 7.1 6.7 7.5 6.7 -15.3 SSS
71078 Sault Ste. Marie 5.5 5.3 4.8 5.0 5.3 4.8 4.0 4.4 4.4 4.5 -22.3 SSS
75010 North Bay 7.6 7.4 6.1 5.8 5.6 5.6 4.7 4.6 4.9 5.1 -34.7 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 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).
  • N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for nitrogen oxides (NOx)

Annual mean (ppb)

ID City/Town 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 20.2 18.9 17.8 16.2 18.0 16.2 14.5 14.4 14.2 13.6 -24.6 SSS
12016 Windsor West 20.6 16.7 16.0 15.2 15.7 15.5 13.5 12.5 11.3 13.0 -27.4 SSS
13001 Chatham 9.0 8.4 7.5 7.7 8.2 8.5 6.8 8.0 6.9 7.2 -14.8 SSS
14111 Sarnia 10.2 11.7 10.7 9.8 10.9 11.7 INS 8.7 9.4 8.5 -19.5 SSS
15020 Grand Bend N/A 4.0 3.9 5.4 3.4 3.8 3.3 3.4 3.4 2.7 -24.0 SSS
15026 London 11.7 11.6 10.5 7.8 8.3 8.0 6.5 6.8 6.2 6.6 -40.8 SSS
21005 Brantford 7.2 7.3 6.7 5.7 6.4 6.8 5.7 5.3 6.2 6.5 -6.3 SSS
26060 Kitchener 10.3 9.6 9.2 8.3 8.5 8.4 7.5 6.9 6.7 7.4 -20.9 SSS
27067 St. Catharines 11.8 10.9 10.6 9.9 9.1 9.4 8.2 7.9 6.8 7.1 -34.7 SSS
28028 Guleph 8.6 9.5 8.8 7.8 8.4 7.7 7.3 7.0 7.1 6.4 -25.6 SSS
29118 Hamilton West N/A 19.5 18.4 18.1 18.7 17.3 17.9 14.2 15.2 16.5 -6.1 SSS
29214 Hamilton Mountain 11.2 12.2 10.5 11.0 11.3 10.9 9.2 9.1 8.9 15.4 -18.7 SSS
31103 Toronto Downtown 20.3 18.4 16.2 16.1 16.5 16.1 15.9 15.7 14.0 10.7 -15.8 SSS
33003 Toronto East 22.6 22.8 20.6 19.4 20.4 19.7 17.5 15.8 13.7 13.7 -38.3 SSS
34021 Toronto North 20.0 21.5 18.5 17.0 17.7 16.9 15.4 13.5 12.8 13.2 -39.7 SSS
35125 Toronto West 33.5 31.5 27.6 24.7 26.5 25.7 23.8 22.7 21.1 22.1 -28.9 SSS
44008 Burlington 17.2 16.4 15.6 15.6 15.5 14.3 14.2 13.2 12.0 12.6 -23.8 SSS
44017 Oakville 12.8 13.0 12.6 11.2 11.6 10.1 10.1 9.9 10.4 10.9 -20.4 SSS
45027 Oshawa 9.5 9.2 7.8 7.4 8.8 8.9 8.8 8.8 4.7 4.4 -30.5 SSS
46090 Brampton 14.4 15.9 14.8 13.9 14.6 13.7 13.1 10.6 10.3 10.74 -34.6 SSS
46108 Mississauga 14.5 14.7 13.4 12.6 12.1 12.3 12.2 9.9 8.8 10.97 -29.1 SSS
47045 Barrie 13.1 12.4 11.3 11.0 11.8 10.9 11.9 9.9 8.3 8.52 -26.8 SSS
48006 Newmarket 9.5 10.3 9.2 8.4 8.2 8.5 8.1 7.8 7.4 6.78 -23.8 SSS
49005 Parry Sound N/A 4.5 3.8 3.4 4.0 4.0 3.6 3.3 3.3 3.34 -20.5 SSS
51001 Ottawa Downtown 9.0 9.7 10.2 10.1 9.3 9.5 8.6 8.6 9.0 8.31 -13.1 SSS
52023 Kingston 4.7 5.3 4.6 3.8 4.8 5.3 5.2 4.9 4.7 4.55 -9.4 SSS
54012 Belleville 7.8 8.7 6.4 6.3 5.7 6.2 6.7 5.4 4.7 5.53 -28.5 SSS
56051 Cornwall 8.5 8.4 8.4 8.0 7.0 7.1 7.6 6.2 6.3 6.54 -19.6 SSS
59006 Peterborough 6.7 6.6 5.4 6.6 7.1 6.6 5.9 5.8 5.3 5.14 -26.0 SSS
63203 Thunder Bay 12.4 14.5 12.4 12.0 11.9 12.7 11 10.8 11.3 10.44 -18.5 SSS
71078 Sault Ste. Marie 7.4 7.2 6.4 6.3 7.3 6.6 5.1 5.8 5.6 5.95 -24.8 SSS
75010 North Bay 11.0 11.5 9.1 8.3 8.1 7.8 6.7 6.2 6.6 6.91 -39.3 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 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).
  • N-SSS - Non-Significant Sen's Slope (significant trend not detected).

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

Annual mean (µg/m3)

ID City/Town 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 9.4 9.4 9.8 9.2 10.1 9.3 8.1 7.8 8.5 7.8 -20.8 SSS
12016 Windsor West 9.6 9.7 9.5 10.0 10.7 9.9 8.5 8.5 8.7 9.1 -12.3 SSS
13001 Chatham 8.1 8.2 7.5 8.1 8.6 8.1 6.6 6.4 6.8 6.8 -20.0 SSS
14111 Sarnia 12.7 12.9 12.7 8.5 9.0 8.4 INS 7.0 7.4 7.1 -46.1 SSS
15020 Grand Bend 7.8 7.6 7.4 7.3 8.1 7.7 6.0 5.1 5.6 5.4 -41.5 SSS
15026 London 7.8 7.7 8.1 9.1 8.8 8.3 7.1 7.0 7.3 6.7 -22.1 SSS
16015 Port Stanley 7.4 7.5 7.4 7.4 8.2 8.0 6.5 6.3 6.8 6.7 -16.5 SSS
18007 Tiverton 5.7 6.0 6.0 5.8 6.5 6.4 5.1 5.1 5.7 5.0 -18.2 SSS
21005 Brantford 8.0 8.2 7.8 8.5 9.2 8.7 7.3 7.2 7.7 7.4 -13.0 SSS
26060 Kitchener 7.8 7.7 7.7 8.7 9.3 8.8 7.3 7.0 7.4 7.2 -13.5 SSS
27067 St. Catharines 8.0 7.8 7.9 8.5 8.8 8.4 6.9 7.0 7.0 7.0 -18.2 SSS
28028 Guelph 7.0 7.4 7.4 8.1 8.9 8.4 6.9 6.8 7.4 7.1 -9.2 N-SSS
29000 Hamilton Downtown 9.4 10.0 10.2 10.1 10.8 10.2 8.2 8.5 9.2 8.8 -18.0 SSS
29118 Hamilton West 8.3 8.8 9.0 9.6 9.9 9.9 7.9 7.5 8.2 7.8 -18.8 SSS
29214 Hamilton Mountain 7.6 8.3 8.1 9.2 9.4 9.0 7.2 7.4 7.7 7.9 -16.1 SSS
33003 Toronto East 8.3 7.8 7.8 8.2 8.9 8.5 7.0 7.4 7.2 7.0 -14.7 SSS
34021 Toronto North 7.7 9.5 9.0 8.3 9.2 9.4 7.3 7.4 7.6 6.8 -26.1 SSS
35125 Toronto West 8.1 8.7 8.8 8.8 9.1 8.5 7.0 7.4 7.7 7.2 -22.6 SSS
44008 Burlington 7.7 7.8 8.0 8.7 9.6 9.4 7.6 7.0 7.2 7.0 -19.8 SSS
44017 Oakville 7.0 8.0 7.6 8.0 8.5 8.3 7.0 6.9 7.4 7.2 -11.5 SSS
45027 Oshawa 7.0 6.9 6.9 7.4 7.7 7.5 5.9 5.9 6.4 6.1 -18.9 SSS
46090 Brampton 7.2 7.6 7.2 8.5 8.9 8.4 6.8 7.0 7.3 6.8 -10.5 N-SSS
46108 Mississauga 7.6 7.7 7.5 7.9 8.7 8.5 7.2 6.8 7.3 7.0 -13.6 SSS
47045 Barrie 6.8 7.2 7.1 7.5 7.6 7.6 6.5 7.0 7.7 7.5 2.5 N-SSS
48006 Newmarket 6.8 6.9 7.1 7.3 7.3 7.1 6.0 5.9 6.4 5.9 -21.2 SSS
49005 Parry Sound 5.5 6.0 6.0 5.8 5.8 5.7 4.8 4.6 5.0 4.4 -32.8 SSS
49010 Dorset 5.1 5.4 5.3 5.4 5.3 5.6 4.6 4.6 4.9 4.1 -17.6 SSS
51001 Ottawa Downtown 5.7 6.3 6.2 7.0 7.0 6.9 5.9 5.9 5.9 5.9 -8.6 N-SSS
51010 Petawawa 4.2 4.5 4.8 4.8 4.7 4.8 4.4 4.1 3.6 3.8 -19.2 SSS
52023 Kingston 8.0 8.5 8.3 6.5 6.8 6.3 5.8 5.3 5.6 5.4 -38.3 SSS
54012 Belleville 5.6 6.2 6.5 6.9 6.8 6.6 5.5 5.8 6.4 6.1 -3.7 N-SSS
56051 Cornwall 7.0 7.3 6.9 7.7 7.0 6.9 6.4 5.9 6.3 5.9 -21.7 SSS
59006 Peterborough 6.3 7.0 6.3 7.4 6.9 6.8 5.8 5.8 6.3 6.0 -16.7 SSS
63203 Thunder Bay 5.4 6.2 5.4 6.3 6.6 6.5 4.9 5.1 6.0 5.1 -11.4 SSS
71078 Sault Ste. Marie 5.2 5.7 5.6 5.6 6.0 5.9 4.9 5.0 5.5 4.8 -8.7 SSS
75010 North Bay 4.9 5.5 5.3 5.2 5.3 5.3 4.6 4.6 5.5 4.5 -14.8 SSS
77233 Sudbury 4.7 5.2 5.1 5.7 6.0 6.3 5.4 5.0 5.4 5.0 3.5 N-SSS

Notes:

  • From 2010-2012, 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 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).
  • N-SSS - Non-Significant Sen's Slope (significant trend not detected).

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

Annual mean (ppb)

ID City/Town 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 28.0 27.2 28.0 26.9 26.0 27.0 27.7 27.3 26.9 26.6 -1.3 Non-SSS
12016 Windsor West 26.7 26.4 28.0 26.7 27.2 26.5 27.7 27.0 27.0 27.3 4.0 Non-SSS
13001 Chatham 31.9 29.7 29.5 29.6 29.3 29.6 29.6 29.5 28.7 29.2 -5.6 SSS
14111 Sarnia 30.7 29.7 29.7 28.6 27.1 27.8 28.8 28.4 29.0 29.2 -3.2 Non-SSS
15020 Grand Bend 35.0 32.8 33.2 32.3 31.0 30.4 30.7 31.0 31.5 31.6 -6.7 SSS
15026 London 28.2 26.8 27.7 28.7 28.1 27.9 28.2 28.1 27.6 26.8 0.7 Non-SSS
16015 Port Stanley 34.6 32.8 33.1 33.9 32.3 32.8 32.9 33.0 32.3 32.3 -3.8 SSS
18007 Tiverton 33.8 32.1 32.0 32.4 31.8 32.5 33.1 32.4 32.3 31.1 -2.2 Non-SSS
21005 Brantford 29.4 28.7 28.8 29.0 29.4 28.9 29.5 28.3 28.3 27.5 -5.0 SSS
26060 Kitchener 29.4 27.6 28.0 28.0 27.3 27.9 28.8 28.1 27.7 27.2 -2.3 Non-SSS
27067 St. Catharines 28.3 28.0 28.7 28.6 28.5 28.6 29.8 28.1 28.5 28.4 2.3 Non-SSS
28028 Guelph 30.7 28.9 28.8 29.0 27.8 27.7 28.7 28.4 28.9 26.3 -6.1 SSS
29000 Hamilton Downtown 26.9 25.4 25.7 25.0 25.3 25.9 26.7 25.6 25.6 24.4 -3.5 Non-SSS
29118 Hamilton West 24.5 24.2 24.2 24.4 22.7 23.9 24.4 25.0 25.5 23.6 1.0 Non-SSS
29214 Hamilton Mountain 29.7 28.8 30.2 29.5 29.1 29.4 29.5 29.1 29.3 27.5 -3.4 Non-SSS
33003 Toronto East 23.0 23.3 24.6 24.1 23.4 23.5 25.5 24.4 25.2 24.6 8.7 SSS
34021 Toronto North 24.8 23.6 25.7 25.3 25.3 25.7 25.9 24.0 25.5 24.1 1.0 Non-SSS
35125 Toronto West 20.6 20.1 21.5 21.5 21.1 21.3 22.1 22.1 22.3 21.8 10.1 SSS
44008 Burlington 26.6 25.9 26.7 26.4 25.5 26.5 27.6 27.1 27.6 26.6 5.6 SSS
44017 Oakville 28.0 26.8 27.7 28.3 27.2 27.4 27.1 27.4 28.7 27.1 0.8 Non-SSS
45027 Oshawa 28.0 26.6 27.0 27.2 27.2 26.2 27.2 27.9 25.8 24.4 -6.1 SSS
46090 Brampton 27.5 26.1 26.6 26.7 26.5 26.5 27.1 27.2 28.6 26.5 3.6 Non-SSS
46108 Mississauga 25.9 24.1 25.6 25.2 25.4 25.4 26.0 26.2 26.1 24.5 2.2 Non-SSS
47045 Barrie 26.8 25.3 26.3 25.5 25.6 25.4 25.9 25.9 27.5 25.7 1.1 Non-SSS
48006 Newmarket 31.5 27.8 29.4 28.7 28.6 28.5 28.6 27.9 29.8 27.8 -2.4 Non-SSS
49005 Parry Sound 31.3 29.7 30.1 30.4 29.6 30.4 29.6 29.7 30.8 29.8 -1.1 Non-SSS
49010 Dorset 28.6 27.0 28.0 28.1 27.7 27.0 27.4 26.9 28.2 27.5 -1.9 Non-SSS
51001 Ottawa Downtown 25.7 24.2 26.0 25.6 24.8 25.6 25.6 25.5 26.4 25.9 3.9 Non-SSS
51010 Petawawa 27.9 26.7 27.7 27.6 26.8 26.7 26.4 25.8 27.3 27.3 -2.1 Non-SSS
52023 Kingston 32.6 30.3 32.7 30.3 31.4 30.3 30.5 30.4 30.5 29.9 -4.1 SSS
54012 Belleville 30.0 27.9 28.0 29.2 29.6 29.6 30.5 30.2 29.9 29.6 6.0 SSS
56051 Cornwall 27.9 26.1 27.1 26.9 27.3 27.9 27.1 27.2 27.6 26.9 0.3 Non-SSS
59006 Peterborough 30.5 27.9 29.1 28.6 29.2 29.3 29.7 28.9 29.7 28.3 -0.4 Non-SSS
63203 Thunder Bay 25.7 25.2 25.0 26.3 23.4 24.0 23.2 23.4 24.3 23.7 -8.8 SSS
71078 Sault Ste. Marie 28.4 27.8 28.8 28.9 28.4 27.8 27.3 28.1 29.7 28.1 -0.7 Non-SSS
75010 North Bay 28.0 26.7 26.1 27.4 26.7 27.0 26.4 26.4 26.0 26.4 -4.2 SSS
77233 Sudbury 28.7 28.7 28.5 27.2 26.3 25.7 25.1 25.9 27.1 26.3 -10.7 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 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).
  • N-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 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 34.6 33.8 36.8 32.5 30.9 33.3 33.4 32.8 33.7 31.4 -8.2 Non-SSS
12016 Windsor West 31.8 31.9 35.7 30.9 30.9 31.8 33.0 31.8 32.4 31.2 -0.2 Non-SSS
13001 Chatham 36.5 34.4 36.6 34.2 32.4 34.4 32.9 33.1 32.1 31.9 -12.1 SSS
14111 Sarnia 34.3 32.9 36.6 32.0 29.4 31.1 32.1 32.0 34.0 31.5 -4.5 Non-SSS
15020 Grand Bend 37.8 33.9 38.9 33.1 31.5 32.3 32.0 32.1 32.7 31.7 -9.4 SSS
15026 London 32.5 30.7 34.4 30.9 29.5 31.0 30.4 29.8 30.5 27.4 -11.2 SSS
16015 Port Stanley 38.9 35.5 38.4 36.9 33.7 35.6 35.2 35.0 35.3 33.7 -12.4 SSS
18007 Tiverton 33.3 31.7 36.0 32.5 30.8 33.3 34.1 32.2 32.9 29.7 -5.8 Non-SSS
21005 Brantford 31.6 31.1 33.5 30.1 29.9 31.2 32.2 29.4 30.4 28.3 -9.4 Non-SSS
26060 Kitchener 31.6 30.2 33.5 29.8 28.5 30.2 31.8 29.8 30.6 29.2 -6.2 Non-SSS
27067 St. Catharines 32.0 31.2 35.0 31.2 29.5 31.7 33.2 29.8 31.3 29.7 -7.3 Non-SSS
28028 Guelph 32.5 31.3 34.5 30.4 28.9 30.2 31.2 29.6 31.7 27.3 -12.3 Non-SSS
29000 Hamilton Downtown 31.6 28.7 32.4 28.4 27.5 29.5 30.6 27.8 29.7 26.1 -13.2 Non-SSS
29118 Hamilton West 27.9 26.2 29.2 26.4 22.7 26.5 27.1 26.8 28.5 24.4 -4.2 Non-SSS
29214 Hamilton Mountain 34.4 32.3 37.4 32.5 31.6 33.9 33.2 31.5 34.0 29.6 -8.9 Non-SSS
33003 Toronto East 26.7 27.4 30.6 27.1 25.9 27.7 29.7 26.0 29.2 26.0 -3.0 Non-SSS
34021 Toronto North 28.0 27.5 32.7 29.4 28.6 30.7 30.7 26.3 30.4 25.9 -6.0 Non-SSS
35125 Toronto West 24.3 23.6 27.5 24.4 23.5 25.0 25.9 24.3 26.3 24.3 3.9 Non-SSS
44008 Burlington 30.2 29.2 32.5 29.2 27.4 30.1 30.5 29.0 31.8 28.8 -1.7 Non-SSS
44017 Oakville 31.5 29.9 34.2 30.6 28.3 30.2 29.9 29.5 32.4 28.8 -9.0 Non-SSS
45027 Oshawa 29.5 28.5 31.1 28.3 27.9 28.9 29.4 28.6 26.6 24.4 -11.7 SSS
46090 Brampton 30.8 29.3 32.7 29.5 28.9 30.3 31.2 29.5 32.7 28.2 -2.6 Non-SSS
46108 Mississauga 29.0 26.7 30.4 26.5 26.5 28.0 28.5 27.2 28.3 24.9 -4.3 Non-SSS
47045 Barrie 27.9 26.2 29.7 25.6 25.4 26.8 27.4 25.6 29.0 24.7 -4.7 Non-SSS
48006 Newmarket 34.4 30.5 34.2 30.3 29.4 31.2 31.7 29.0 33.2 28.4 -7.4 Non-SSS
49005 Parry Sound 30.4 28.7 32.8 30.1 28.2 31.4 28.9 27.7 30.9 27.8 -4.8 Non-SSS
49010 Dorset 25.2 23.8 28.3 25.3 24.4 24.6 25.1 23.0 25.8 23.9 -4.0 Non-SSS
51001 Ottawa Downtown 26.1 25.1 29.3 26.5 24.6 27.8 27.5 25.3 27.6 25.6 1.2 Non-SSS
51010 Petawawa 23.8 22.8 28.1 24.5 22.9 24.4 23.4 21.1 23.7 22.9 -5.3 Non-SSS
52023 Kingston 35.9 32.0 38.5 32.4 32.7 32.2 33.3 30.9 33.1 30.0 -10.8 Non-SSS
54012 Belleville 34.2 29.9 32.7 30.6 30.4 33.2 33.7 30.9 32.4 30.0 -2.8 Non-SSS
56051 Cornwall 29.8 26.7 30.7 28.1 27.0 29.7 28.7 27.1 29.4 26.1 -5.7 Non-SSS
59006 Peterborough 32.0 29.8 34.2 29.5 30.0 31.5 32.3 29.2 32.2 28.1 -5.3 Non-SSS
63203 Thunder Bay 23.9 24.2 25.3 24.7 22.7 23.6 22.0 20.4 22.1 21.8 -15.5 SSS
71078 Sault Ste. Marie 27.2 26.4 30.3 28.2 27.4 28.1 26.3 26.3 29.1 26.2 -2.2 Non-SSS
75010 North Bay 28.4 26.3 28.5 26.9 26.2 27.8 26.4 24.7 26.3 25.7 -8.4 SSS
77233 Sudbury 26.3 26.9 29.8 28.0 27.0 27.7 26.6 25.8 28.8 25.9 -4.4 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 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).
  • N-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 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 23.2 22.5 21.7 22.8 22.8 22.4 23.6 23.3 22.4 23.1 1.4 Non-SSS
12016 Windsor West 22.8 22.5 22.3 23.4 24.5 22.7 23.9 23.6 23.1 24.4 5.5 Non-SSS
13001 Chatham 28.5 26.7 24.3 26.2 27.1 26.3 27.2 26.8 26.2 27.4 0.3 Non-SSS
14111 Sarnia 28.1 27.4 24.7 26.2 25.4 25.4 INS 26.0 25.4 27.6 -1.9 Non-SSS
15020 Grand Bend 33.0 32.1 29.1 31.8 30.6 29.1 29.8 30.2 30.7 31.6 -3.9 Non-SSS
15026 London 25.0 24.2 22.9 26.9 27.1 25.8 26.6 26.9 25.6 26.4 6.4 Non-SSS
16015 Port Stanley 31.5 31.0 29.3 31.8 31.3 31.2 31.2 31.5 30.2 31.4 -0.5 Non-SSS
18007 Tiverton 34.1 32.2 29.2 32.4 32.7 31.9 32.4 32.6 31.9 32.1 -1.1 Non-SSS
21005 Brantford 27.8 27.1 25.4 28.3 28.8 27.2 27.7 27.5 26.7 26.9 -2.3 Non-SSS
26060 Kitchener 27.8 25.7 24.0 26.7 26.5 26.1 26.6 27.1 25.6 25.8 -2.7 Non-SSS
27067 St. Catharines 25.6 25.8 24.1 26.8 27.9 26.3 27.2 27.0 26.4 27.5 6.4 SSS
28028 Guelph 29.3 27.2 24.8 28.0 27.0 26.0 26.8 27.5 26.9 25.7 -5.6 Non-SSS
29000 Hamilton Downtown 23.5 23.1 20.9 22.5 23.7 23.3 23.9 24.2 22.6 23.2 2.6 Non-SSS
29118 Hamilton West 22.1 22.7 20.6 23.0 22.8 22.1 22.5 23.7 23.3 23.0 5.0 SSS
29214 Hamilton Mountain 26.3 26.3 25.0 27.3 27.3 26.3 26.8 27.4 25.9 25.9 1.0 Non-SSS
33003 Toronto East 20.4 20.4 20.3 22.0 21.6 20.5 22.5 23.3 22.4 23.5 13.8 SSS
34021 Toronto North 22.5 20.8 20.7 22.3 22.8 22.1 22.6 22.3 22.0 22.8 3.0 Non-SSS
35125 Toronto West 18.0 17.7 17.2 19.5 19.4 18.6 19.4 20.5 19.4 20.1 11.4 SSS
44008 Burlington 23.9 23.5 22.5 24.4 24.1 23.8 25.6 25.7 24.7 25.2 6.8 SSS
44017 Oakville 25.5 24.7 23.1 26.6 26.5 25.3 25.1 25.9 26.0 26.0 2.6 Non-SSS
45027 Oshawa 26.9 25.2 24.1 26.4 26.7 24.3 25.6 27.3 25.4 24.5 -3.0 Non-SSS
46090 Brampton 25.2 23.8 22.2 24.6 24.8 23.8 24.1 25.6 25.6 25.3 6.8 Non-SSS
46108 Mississauga 23.7 22.5 22.2 24.3 24.7 23.6 24.2 25.5 24.6 24.2 7.5 Non-SSS
47045 Barrie 26.0 24.7 23.9 25.5 25.8 24.4 24.8 26.3 26.5 26.4 5.6 Non-SSS
48006 Newmarket 29.4 25.8 26.0 27.5 28.1 26.6 26.3 27.2 27.3 27.3 2.6 Non-SSS
49005 Parry Sound 31.9 30.4 28.1 30.6 30.6 29.8 30.0 31.1 30.7 31.3 2.2 Non-SSS
49010 Dorset 31.0 29.5 27.7 30.1 30.1 28.8 29.0 29.6 30.0 30.1 0.7 Non-SSS
51001 Ottawa Downtown 25.5 23.6 23.5 24.9 25.1 24.0 24.3 25.6 25.5 26.2 6.8 SSS
51010 Petawawa 30.8 29.5 27.5 29.9 29.6 28.5 28.6 29.3 29.8 30.4 1.4 Non-SSS
52023 Kingston 30.0 29.0 28.6 28.8 30.4 28.9 28.5 30.2 28.6 29.9 -0.3 Non-SSS
54012 Belleville 27.0 26.4 24.6 28.2 29.1 27.0 28.2 29.7 28.1 29.3 10.6 Non-SSS
56051 Cornwall 26.5 25.7 24.2 25.7 27.6 26.6 26.0 27.4 26.3 27.5 3.9 Non-SSS
59006 Peterborough 29.5 26.6 25.5 28.0 28.6 27.7 27.8 28.7 27.9 28.5 1.9 Non-SSS
63203 Thunder Bay 27.1 26.1 24.7 27.4 23.8 24.2 24.2 25.6 25.9 25.1 -4.8 Non-SSS
71078 Sault Ste. Marie 29.3 28.9 27.6 29.4 29.2 27.7 28.0 29.5 30.2 29.5 2.6 Non-SSS
75010 North Bay 27.7 27.0 24.4 27.8 27.1 26.4 26.4 27.6 25.9 26.9 -3.0 Non-SSS
77233 Sudbury 30.5 30.0 27.6 26.6 25.8 24.3 24.0 26.1 26.0 26.7 -16.7 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 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).
  • N-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 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 3.5 3.5 2.8 2.4 2.4 1.9 1.1 1.0 0.6 0.4 -97.1 SSS
12016 Windsor West 3.2 3.4 2.8 2.6 2.8 1.9 1.4 0.9 0.7 0.8 -89.8 SSS
14111 Sarnia 3.9 5.3 4.1 3.8 3.5 3.2 INS 1.7 1.9 1.9 -76.3 SSS
29000 Hamilton Downtown 3.3 5.2 4.8 4.8 5.1 4.3 3.2 3.5 5.0 4.8 -12.8 Non-SSS
29214 Hamilton Mountain 2.9 4.1 3.7 2.8 2.9 2.6 1.8 1.8 2.4 3.5 -45.5 SSS
35125 Toronto West 0.9 1.5 0.6 0.6 0.7 1.0 0.6 0.5 0.3 0.3 -76.7 SSS
51001 Ottawa Downtown 0.2 0.4 0.3 0.3 0.3 0.4 0 0.1 0.2 0.2 -26.8 Non-SSS
71078 Sault Ste. Marie 0.7 0.8 0.6 0.8 0.8 0.8 0.6 0.7 0.8 0.7 -12.2 Non-SSS
77233 Sudbury 1.3 1.5 1.3 2.8 2.4 2.4 2.1 1.3 1.2 1.2 -29.9 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 77233 replaced station 77219 as the Sudbury site in 2013.
  • SSS - Significant Sen's Slope (significant trend detected).
  • N-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 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12008 Windsor Downtown 2.5 3.8 2.1 1.9 1.8 1.9 2.3 2.6 1.9 2.3 -7.3 N-SSS
29000 Hamilton Downtown 2.2 1.8 1.7 2.0 2.9 1.3 1.4 2.1 1.7 1.9 -6.3 N-SSS
35125 Toronto West 1.8 1.4 1.4 1.4 1.6 1.3 1.7 1.2 0.9 1.5 -15.8 N-SSS
51001 Ottawa Downtown 1.5 1.5 0.9 0.9 0.8 0.8 0.9 0.7 1.0 0.7 -38.0 SSS

Notes:

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

10-year trend for benzene

Annual mean (µg/m3)

ID City/Town 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.687 INS 0.558 0.519 0.610 0.566 0.521 0.450 0.478 0.445 -28.9 SSS
14111 Sarnia 0.961 INS 0.900 0.820 1.007 1.191 0.689 0.604 0.574 0.419 -42.3 SSS
15026 London 0.490 INS 0.455 0.413 0.446 0.451 0.341 0.339 0.321 0.296 -39.5 SSS
26060 Kitchener 0.537 INS 0.479 N/A 0.483 0.548 0.395 0.446 0.355 0.290 -41.6 SSS
29000 Hamilton Downtown 1.060 INS 0.977 INS 0.899 1.092 0.675 0.569 0.639 0.568 -35.1 SSS
48006 Newmarket 0.416 N/A 0.371 0.406 0.422 0.425 0.328 0.385 INS 0.250 -32.4 SSS
51001 Ottawa Downtown 0.451 0.418 0.422 0.442 0.413 0.453 0.365 0.388 0.405 0.323 -20.7 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 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12016 Windsor West 1.679 INS 1.392 1.017 1.542 1.248 1.272 0.972 1.131 0.797 -35.7 SSS
14111 Sarnia 2.037 INS 2.539 1.587 1.908 2.350 1.778 1.550 1.014 0.779 -41.1 SSS
15026 London 1.334 INS 1.408 0.887 0.839 1.013 0.727 0.633 0.657 0.491 -50.9 SSS
26060 Kitchener 1.477 INS 1.322 N/A 1.278 1.052 1.020 1.002 0.625 0.572 -47.7 SSS
29000 Hamilton Downtown 2.842 INS 2.067 INS 2.229 2.249 1.642 1.296 0.862 0.817 -47.2 SSS
48006 Newmarket 0.878 N/A 0.877 0.916 0.732 1.340 1.118 0.807 INS 0.418 -30.8 SSS
51001 Ottawa Downtown 1.212 0.929 0.899 0.975 0.741 0.982 0.902 0.826 0.704 0.618 -29.4 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 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.275 INS 0.221 0.179 0.267 0.238 0.234 0.181 0.187 0.137 -37.4 SSS
14111 Sarnia 0.392 INS 0.278 0.255 0.253 0.362 0.282 0.211 0.235 0.118 -36.6 SSS
15026 London 0.190 INS 0.143 0.125 0.121 0.149 0.108 0.105 0.141 0.070 -43.5 SSS
26060 Kitchener 0.220 INS 0.162 N/A 0.167 0.168 0.159 0.164 0.109 0.079 -37.9 SSS
29000 Hamilton Downtown 0.278 INS 0.193 INS 0.192 0.210 0.186 0.187 0.129 0.126 -28.7 SSS
48006 Newmarket 0.154 N/A 0.115 0.134 0.125 0.249 0.215 0.130 INS 0.067 -29.4 SSS
51001 Ottawa Downtown 0.144 0.122 0.105 0.112 0.099 0.123 0.119 0.120 0.088 0.064 -24.9 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).
  • N-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 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.818 INS 0.689 0.536 0.825 0.702 0.635 0.505 0.502 0.409 -41.9 SSS
14111 Sarnia 0.790 INS 0.676 0.510 0.629 0.850 0.495 0.499 0.563 0.256 -32.3 SSS
15026 London 0.500 INS 0.388 0.345 0.318 0.398 0.267 0.268 0.407 0.200 -38.2 SSS
26060 Kitchener 0.639 INS 0.478 N/A 0.469 0.464 0.434 0.451 0.276 0.223 -39.1 SSS
29000 Hamilton Downtown 0.842 INS 0.603 INS 0.594 0.621 0.518 0.532 0.359 0.398 -30.2 SSS
48006 Newmarket 0.437 N/A 0.333 0.362 0.334 0.582 0.484 0.350 INS 0.191 -33.6 SSS
51001 Ottawa Downtown 0.429 0.355 0.310 0.329 0.309 0.363 0.338 0.334 0.222 0.186 -30.6 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).
  • N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for o-xylene

Annual mean (µg/m3)

ID City/Town 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.255 INS 0.228 0.184 0.283 0.239 0.232 0.190 0.184 0.147 -32.2 SSS
14111 Sarnia 0.262 INS 0.244 0.171 0.226 0.313 0.178 0.192 0.213 0.101 -30.2 SSS
15026 London 0.147 INS 0.126 0.118 0.113 0.146 0.103 0.103 0.148 0.074 -31.8 SSS
26060 Kitchener 0.188 INS 0.157 N/A 0.166 0.164 0.153 0.164 0.107 0.082 -40.9 SSS
29000 Hamilton Downtown 0.241 INS 0.195 INS 0.206 0.216 0.189 0.198 0.131 0.145 -18.5 SSS
48006 Newmarket 0.133 N/A 0.116 0.126 0.134 0.218 0.192 0.128 INS 0.068 -24.8 N-SSS
51001 Ottawa Downtown 0.147 0.128 0.118 0.118 0.111 0.136 0.127 0.132 0.089 0.078 -18.5 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).
  • N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for 1,3-butadiene

Annual mean (µg/m3)

ID City/Town 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Change
over
10 year
(%)		 Trend
12016 Windsor West 0.056 INS 0.048 0.036 0.042 0.035 0.032 0.034 0.028 0.028 -41.0 SSS
14111 Sarnia 0.167 INS 0.205 0.209 0.124 0.216 0.089 0.077 0.088 0.054 -46.8 SSS
15026 London 0.050 INS 0.040 0.023 0.025 0.026 0.020 0.035 0.025 0.025 -36.0 SSS
26060 Kitchener 0.056 INS 0.042 N/A 0.029 0.029 0.023 0.038 0.026 0.025 -35.1 SSS
29000 Hamilton Downtown 0.060 INS 0.046 INS 0.032 0.037 0.025 0.039 0.028 0.028 -31.5 SSS
48006 Newmarket 0.051 N/A 0.039 0.021 0.020 0.028 0.024 0.035 INS 0.025 -32.2 SSS
51001 Ottawa Downtown 0.052 0.041 0.040 0.035 0.026 0.030 0.027 0.037 0.032 0.027 -36.9 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).

Canadian Ambient Air Quality Standard reporting

PM2.5 and ozone CAAQS metric values for designated sites across Ontario (2019)

Air zone area City/Town 24-hour PM2.5
(μg/m3)		 Annual PM2.5
(μg/m3)		 8-hour ozone
(ppb)
Sarnia Sarnia 19 7.2 71*(44)
Hamilton Hamilton Downtown 22 8.8 62(44)
Hamilton Hamilton Mountain 20 7.6 65*(48)
Sudbury Sudbury 14 5.2 60(45)
Sault Ste. Marie Sault Ste. Marie 13 5.1 57(46)
Northern Ontario Thunder Bay 14 5.4 50(47)
Southern Ontario Windsor Downtown 20 8.1 70*(42)
Southern Ontario Chatham 17 6.7 64*(49)
Southern Ontario London 18 7.2 65*(48)
Southern Ontario Brantford 18 7.4 63(50)
Southern Ontario Kitchener 19 7.2 63(50)
Southern Ontario Guelph 19 7.1 63(49)
Southern Ontario St. Catharines 17 7 62(47)
Southern Ontario Burlington 18 7.1 66*(48)
Southern Ontario Oakville 19 7.1 65*(48)
Southern Ontario Milton 19 7.4 67*(51)
Southern Ontario Mississauga 19 7.1 62(47)
Southern Ontario Brampton 20 7.1 65*(50)
Southern Ontario Toronto 19 7.7 65*(49)
Southern Ontario Oshawa 17 6.1 63(48)
Southern Ontario Barrie 20 7.4 58(47)
Southern Ontario Peterborough 16 6.1 63(49)
Southern Ontario Kingston 15 5.5 64*(50)
Southern Ontario Ottawa Downtown 15 5.8 57(48)

Notes:

  • Designated sites normally refer to communities with populations greater than 100,000.
  • Toronto reporting is based on Toronto Downtown, Toronto North, Toronto East and Toronto West stations.
  • The CAAQS for 24h PM2.5 is 28 µg/m3 based on the 98th percentile measurement annually, averaged over three consecutive years.
  • The CAAQS for annual PM2.5 is 10 µg/m3 based on the annual mean averaged over three consecutive years.
  • The CAAQS for ozone is 63 ppb based on the consecutive three-year average of the annual 4th highest daily maximum eight-hour running average.
  • An asterisk indicates an exceedance of the CAAQS.
  • Value in parenthesis is the calculated 8h ozone CAAQS metric once the transboundary influence was removed.

PM2.5 and ozone CAAQS metric trends for designated sites across Ontario (2010-2019)

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 -43.5 -51.4 -6.3*
Hamilton Hamilton Downtown -23.1 -7.4* -7.8
Hamilton Hamilton Mountain -18 -6.2* -8.5
Sudbury Sudbury -8.6 9.0* -10.2
Sault Ste. Marie Sault Ste. Marie -24.1 -7.3* -9.5
Northern Ontario Thunder Bay -18.8 -2.1* -8.3
Southern Ontario Windsor Downtown -23.1 -15.6 -8.1
Southern Ontario Chatham 31.3 -21.2 -12.3
Southern Ontario London -13 -11.3* 0*
Southern Ontario Brantford -23.5 -6.7* -12.5
Southern Ontario Kitchener -15.7* -6.9* -4.4*
Southern Ontario Guelph -10.2* -3.0* -6.4*
Southern Ontario St. Catharines -26.1* -12.4* -8.1
Southern Ontario Burlington -18.8 -7.9* -6.4
Southern Ontario Oakville -11.7 -3.4* -8.5
Southern Ontario Mississauga -11.2* -8.0* -3.4*
Southern Ontario Brampton -5.6* -3.3* -4.9
Southern Ontario Toronto -27.7 -16 -8.7
Southern Ontario Oshawa -20.5 -14.1* -8.6
Southern Ontario Barrie -6.8 4.2* -10.1
Southern Ontario Peterborough -24.5 -11.2* 10.3
Southern Ontario Kingston -58.3 -40.7 -15.6
Southern Ontario Ottawa Downtown -13.5* -6.1* -7.4*

Notes:

  • Designated sites normally refer to communities with populations greater than 100,000.
  • Toronto reporting is based on Toronto Downtown, Toronto North, Toronto East and Toronto West stations.
  • *Non-Significant Sen’s Slope (significant trend not detected).

AQHI and Air Quality Alert Program Reporting

2019 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 8444 1.85 42.12 44.56 10.23 1.20 0.02 0.01 0 0 0 0 1
12016 Windsor West 8613 2.23 41.65 43.75 10.84 1.45 0.08 0 0 0 0 0 0
13001 Chatham 8694 9.73 53.29 31.19 5.56 0.23 0 0 0 0 0 0 0
14111 Sarnia 8684 8.92 51.20 31.20 7.30 1.27 0.07 0.05 0 0 0 0 4
15020 Grand Bend 8449 16.63 60.58 19.82 2.64 0.25 0 0.08 0 0 0 0 3
15026 London 8735 14.59 56.34 25.80 3.10 0.17 0 0 0 0 0 0 0
16015 Port Stanley 8673 12.87 54.51 28.29 4.06 0.27 0 0 0 0 0 0 0
18007 Tiverton 8632 14.61 63.00 20.41 1.85 0.12 0 0.01 0 0 0 0 1
21005 Brantford 8708 13.78 53.67 28.16 4.13 0.16 0.06 0.03 0 0 0 0 2
26060 Kitchener 8711 11.24 55.17 29.71 3.35 0.32 0.20 0.01 0 0 0 0 1
27067 St. Catharines 8604 8.60 56.66 31.32 3.24 0.17 0 0 0 0 0 0 0
28028 Guelph 8722 15.08 57.74 23.91 3.00 0.23 0.05 0 0 0 0 0 0
29000 Hamilton Downtown 8585 2.83 38.25 44.34 11.87 2.48 0.22 0 0 0 0 0 0
29118 Hamilton West 8724 5.90 44.92 38.87 8.93 1.24 0.14 0 0 0 0 0 0
29214 Hamilton Mountain 8691 5.10 47.52 37.84 7.71 1.67 0.16 0 0 0 0 0 0
31103 Toronto Downtown 2880 0.56 29.90 49.72 14.38 4.90 0.56 0 0 0 0 0 0
31129 Toronto Downtown 4570 2.41 43.74 39.91 12.28 1.60 0.07 0 0 0 0 0 0
33003 Toronto East 8719 6.79 50.29 34.77 7.00 0.80 0.23 0.07 0.05 0 0 0 2
34021 Toronto North 8535 9.00 46.46 34.90 8.04 1.35 0.18 0.08 0 0 0 0 1
35125 Toronto West 8505 2.12 39.93 46.27 10.03 1.20 0.39 0.06 0.01 0 0 0 2
44008 Burlington 8666 4.66 48.20 39.51 6.70 0.82 0.10 0 0 0 0 0 0
44017 Oakville 8618 5.06 47.96 38.85 7.14 0.87 0.13 0 0 0 0 0 0
44029 Milton 8521 3.84 51.00 36.99 7.29 0.81 0.07 0 0 0 0 0 0
45027 Oshawa 8667 25.57 61.69 12.06 0.68 0 0 0 0 0 0 0 0
46090 Brampton 8657 7.95 51.05 33.88 6.04 0.89 0.18 0.01 0 0 0 0 1
46108 Mississauga 8667 9.59 56.13 29.20 4.67 0.33 0.07 0 0 0 0 0 0
47045 Barrie 8493 13.28 56.98 25.53 3.83 0.33 0.06 0 0 0 0 0 0
48006 Newmarket 8668 14.24 59.07 22.70 3.67 0.21 0.07 0.05 0 0 0 0 1
49005 Parry Sound 8605 19.54 65.23 13.88 1.30 0.06 0 0 0 0 0 0 0
49010 Dorset 8640 24.42 61.25 13.94 0.39 0 0 0 0 0 0 0 0
51001 Ottawa Downtown 8481 16.05 52.89 27.32 3.56 0.18 0 0 0 0 0 0 0
51010 Petawawa 8631 26.62 62.00 11.27 0.10 0 0 0 0 0 0 0 0
52023 Kingston 8726 12.81 63.73 21.49 1.94 0.03 0 0 0 0 0 0 0
54012 Belleville 8582 11.16 63.37 22.76 2.65 0.07 0 0 0 0 0 0 0
56051 Cornwall 8699 17.00 60.23 21.06 1.52 0.20 0 0 0 0 0 0 0
59006 Peterborough 8715 18.26 59.66 19.61 2.41 0.07 0 0 0 0 0 0 0
63203 Thunder Bay 8441 22.07 55.76 20.03 2.10 0.04 0 0 0 0 0 0 0
71078 Sault Ste. Marie 8623 19.18 57.85 21.38 1.52 0.07 0 0 0 0 0 0 0
75010 North Bay 8664 19.61 62.30 15.84 2.11 0.14 0 0 0 0 0 0 0
77233 Sudbury 8682 14.33 59.77 21.73 3.50 0.63 0.03 0 0 0 0 0 0
81103 Toronto Downtown 1185 1.27 42.53 45.57 10.63 0 0 0 0 0 0 0 0

2019 air quality alert summary

Air quality forecast region Special air quality statement Smog and air health advisory
Algonquin 0 0
Atikokan - Upsala - Quetico 1 0
Attawapiskat 1 0
Bancroft - Bon Echo Park 0 0
Barrie - Orillia - Midland 0 0
Belleville - Quinte - Northumberland 0 0
Big Trout Lake - Sachigo Lake 1 0
Brockville - Leeds and Grenville 0 0
Burk's Falls - Bayfield Inlet 0 0
Chapleau - Gogama 1 0
City of Hamilton 0 0
City of Ottawa 0 0
City of Thunder Bay 0 0
City of Toronto 1 0
Cornwall - Morrisburg 0 0
Dryden - Ignace 1 0
Dufferin - Innisfil 0 0
Dunnville - Caledonia - Haldimand 0 0
Elgin 0 0
Elliot Lake - Ranger Lake 0 0
Fort Frances - Rainy Lake 1 0
Fort Hope - Webequie 1 0
Fort Severn 1 0
Geraldton - Manitouwadge - Hornepayne 1 0
Greater Sudbury and Vicinity 0 0
Grey - Bruce 0 0
Haliburton 0 0
Halton - Peel 0 0
Huron - Perth 0 1
Kapuskasing - Hearst 1 0
Kenora - Nestor Falls 1 0
Kingston - Prince Edward 0 0
Kirkland Lake - New Liskeard - Temagami 0 0
Lake Nipigon - Wabakimi 1 0
London - Middlesex 0 0
Manitoulin - Northshore - Killarney 0 0
Moosonee - Fort Albany 1 0
Niagara 0 0
Nipigon - Marathon - Superior North 0 0
North Bay - West Nipissing 0 0
Oxford - Brant 0 0
Parry Sound - Muskoka 0 0
Peawanuck 1 0
Peterborough - Kawartha Lakes 0 0
Pickle Lake - Wunnummin Lake 2 0
Prescott and Russell 0 0
Red Lake - Ear Falls 2 0
Renfrew - Pembroke - Barry's Bay 0 0
Sandy Lake - Pikangikum 2 0
Sarnia - Lambton 1 0
Sault Ste. Marie - Superior East 0 0
Simcoe - Delhi - Norfolk 0 0
Sioux Lookout - Savant Lake 1 0
Smiths Falls - Lanark - Sharbot Lake 0 0
Stirling - Tweed - South Frontenac 0 0
Superior West 1 0
Timmins - Cochrane 1 0
Waterloo - Wellington 0 0
Wawa - White River - Pukaskwa 0 0
Windsor - Essex - Chatham - Kent 0 0
York - Durham 0 0
Ontario 4 1

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