Air quality in Ontario

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

Last update at (local time)

LIVE AQI CITY RANKING

Real-time Ontario
Most polluted city ranking

#cityUS AQI
1 London

55

2 Woodstock

45

3 Barrie

37

4 Brampton

37

5 Newmarket

37

6 Sarnia

37

7 Sudbury

37

8 Windsor

35

9 Mississauga

34

10 Ancaster

33

(local time)

SEE WORLD AQI RANKING

Air Quality Data contributor(s)

Station(s) operated by

Contributors

43

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LIVE AQI CITY RANKING

Real-time Ontario
Cleanest city ranking

#cityUS AQI
1 Chatham

8

2 Kitchener

8

3 Almonte

9

4 St. Catharines

12

5 Burlington

16

6 Oshawa

17

7 Peterborough

17

8 Thunder Bay

17

9 Hamilton

19

10 Kingston

19

(local time)

SEE WORLD AQI RANKING
Good
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Unhealthy for sensitive groups
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