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 Mississauga

33

2 Grand Bend

32

3 Hamilton

32

4 Oshawa

32

5 St. Catharines

32

6 Tiverton

32

7 Chatham

31

8 Newmarket

31

9 Belleville

30

10 Dorset

30

(local time)

SEE WORLD AQI RANKING

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LIVE AQI CITY RANKING

Real-time Ontario
Cleanest city ranking

#cityUS AQI
1 Ajax

0

2 Kirkland Lake

0

3 Markham

0

4 Niagara Falls

0

5 Niagara on the Lake

0

6 Woodstock

3

7 Burlington

4

8 Guelph

4

9 Almonte

5

10 Renfrew

5

(local time)

SEE WORLD AQI RANKING

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Hazardous
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