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Air quality in Ontario

Air quality index (AQI⁺) and PM2.5 air pollution in Ontario • 04:16, Nov 09

Government of Ontario, Ministry of the EnvironmentOklahoma Department of Environmental Quality AnonymousJim GuilletNational Air Pollution Surveillance ProgramPiéEVCOChris Fournier**@airqualitybrampton & airqualitybrampton@gmail.comMark OberemkGraydonSouth RichvaleHamilton Air Monitoring Network - HAMNMC2025Stacey SchacterstevepaulquinnBelltown - Oakley AveMeAmy CuriousKevin DamenNichols FamilyAnonymousElectric Vehicle Council of OttawaCSA HamiltonianMikoAirJayDeeVBbsummAnonymous DGEC - GreensvilleSlyyyMinistry of the Environment and the Fight against Climate ChangePaulSteven RichieAnonymousrandalljhowardARTSean StewartJackBBriarwood Ave. Matt WojtowiczDataforge CanadaSWBradley SangerBijanMichiruWildflower Bee Farm Ontario and Nova ScotiaTimothy DresserBBT Batteries Ltd.Captain Benjamin WillardEric SteinLara TAnonymousHaig BlvdDave McKeeCanadian Air and Precipitation Monitoring NetworkKatwyks on the RiverPierreJpSMeS WepplerMitch LPeter CornelisseAnonymousGregMattAnonymous contributor
1 stations sponsored by The Foundation for Clean Air
Government of Ontario, Ministry of the EnvironmentOklahoma Department of Environmental Quality AnonymousJim GuilletNational Air Pollution Surveillance ProgramPiéEVCOChris Fournier**@airqualitybrampton & airqualitybrampton@gmail.comMark OberemkGraydonSouth RichvaleHamilton Air Monitoring Network - HAMNMC2025Stacey SchacterstevepaulquinnBelltown - Oakley AveMeAmy CuriousKevin DamenNichols FamilyAnonymousElectric Vehicle Council of OttawaCSA HamiltonianMikoAirJayDeeVBbsummAnonymous DGEC - GreensvilleSlyyyMinistry of the Environment and the Fight against Climate ChangePaulSteven RichieAnonymousrandalljhowardARTSean StewartJackBBriarwood Ave. Matt WojtowiczDataforge CanadaSWBradley SangerBijanMichiruWildflower Bee Farm Ontario and Nova ScotiaTimothy DresserBBT Batteries Ltd.Captain Benjamin WillardEric SteinLara TAnonymousHaig BlvdDave McKeeCanadian Air and Precipitation Monitoring NetworkKatwyks on the RiverPierreJpSMeS WepplerMitch LPeter CornelisseAnonymousGregMattAnonymous contributor
1 stations sponsored by The Foundation for Clean Air

Live most polluted city ranking

Real-time Ontario most polluted city ranking

#CitiesAQI⁺ US
1
The national flag of Canada

Chatham

58

2
The national flag of Canada

Cornwall

50

3
The national flag of Canada

Bells Corners

46

4
The national flag of Canada

Amherstburg

38

5
The national flag of Canada

Brockville

37

6
The national flag of Canada

Windsor

35

7
The national flag of Canada

Hawkesbury

34

8
The national flag of Canada

Ottawa

34

9
The national flag of Canada

Merrickville-Wolford

32

10
The national flag of Canada

Nepean

31

Live cleanest city ranking

Real-time Ontario cleanest city ranking

#CitiesAQI⁺ US
1
The national flag of Canada

Ajax

0

2
The national flag of Canada

Algoma

0

3
The national flag of Canada

Ancaster

0

4
The national flag of Canada

Etobicoke

0

5
The national flag of Canada

Lindsay

0

6
The national flag of Canada

North York

0

7
The national flag of Canada

Orangeville

0

8
The national flag of Canada

Orillia

0

9
The national flag of Canada

Woodstock

0

10
The national flag of Canada

Erin

1

Wildfires in Ontario

Real-time information

Active fires

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Which is the most polluted city in Ontario?