Air quality in Ontario

Air quality index (AQI) and PM2.5 air pollution in Ontario

LAST UPDATE (local time)

LIVE AQI CITY RANKING

Real-time Ontario
Most polluted city ranking

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#cityUS AQI
1 Markham

33

2 Thunder Bay

28

3 Kitchener

27

4 Burlington

25

5 London

25

6 Oakville

25

7 Windsor

25

8 Brantford

23

9 Cornwall

23

10 Hamilton

23

(local time)

SEE WORLD AQI RANKING

Air Quality Data contributor(s)

Station(s) operated by

Contributors

4

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LIVE AQI CITY RANKING

Real-time Ontario
Cleanest city ranking

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#cityUS AQI
1 Kirkland Lake

3

2 Algoma

4

3 Parry Sound

4

4 St. Catharines

4

5 North Bay

8

6 Port Stanley

8

7 Sarnia

8

8 Simcoe

8

9 Tiverton

8

10 Nepean

10

(local time)

SEE WORLD AQI RANKING
Good
Moderate
Unhealthy for sensitive groups
Unhealthy
Very unhealthy
Hazardous
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