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Air quality in Ontario
Air quality index (AQI) and PM2.5 air pollution in Ontario
AIR QUALITY DATA CONTRIBUTORS
95 Contributors
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LIVE AQI CITY RANKING
Real-time Ontario
Cleanest city ranking
| # | city | US AQI |
|---|---|---|
| 1 | Kirkland Lake | 4 |
| 2 | Renfrew | 10 |
| 3 | Niagara Falls | 12 |
| 4 | Orillia | 12 |
| 5 | St. Catharines | 12 |
| 6 | Burlington | 16 |
| 7 | Bluewater | 17 |
| 8 | Innisfil | 17 |
| 9 | Parry Sound | 17 |
| 10 | Quinte West | 17 |
(local time)
SEE WORLD AQI RANKING
3D animated air pollution map
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The latest air quality news and resources.
Ontario air quality data attribution
95Contributors
- Hamilton Air Monitoring Network - HAMN
9 stations
- Township of SNNF
1 station
4 Government Contributors
- DGEC - Greensville
1 station
- Electric Vehicle Council of Ottawa
1 station
- EVCO
1 station
National Air Pollution Surveillance Program2 stations
4 Non-profit organization Contributors
MikoAirOne1 station
- Anonymous
1 station
- Jim Guillet
1 station
- bsumm
1 station
Chris Fournier1 station
Slyyy1 station
- Shawn K
1 station
Christopher Trevors1 station
- Anonymous
1 station
Nichols Family1 station
- Bruce Buckley
1 station
Graydon1 station
- IQAir Lab
1 station
Anonymous1 station
CS3 stations
- VB
1 station
- randalljhoward
1 station
- **
1 station
- Bijan
1 station
- Libby
1 station
- Mark Douglas Wessel
1 station
- JayDee
1 station
Me1 station
- Keevabay
1 station
24 Individual Contributors
63 Anonymous contributors63 stations
63 Anonymous Contributors
Which is the most polluted city in Ontario?
- Coldwater 61
- Sudbury 56
- Waterloo 56
- Vaughan 45
- Experimental Lakes 42
- North Bay 39
- Oakville 38
- Fort Erie 37
- Pickle Lake 35
- Ajax 33
- Kitchener 33
- Markham 33
- Richmond Hill 33
- Thunder Bay 33
- Dorset 32
- Newmarket 31
- Tiverton 31
- Algoma 30
- Orangeville 30
- Sarnia 30
- Bonner Lake 29
- Cambridge 29
- Milton 29
- Sault Ste Marie 28
- Concord 27
- Kingston 27
- Windsor 27
- Belleville 26
- Chatham 26
- Mississauga 26
- Scarborough 26
- Toronto 26
- Brantford 25
- Cornwall 25
- Egbert 25
- Hamilton 25
- London 25
- Niagara on the Lake 25
- Stratford 25
- Grand Bend 24
- Paris 24
- Pickering 24
- Walpole Island 24
- Guelph 23
- Keswick 23
- North Perth 23
- Port Stanley 23
- Uxbridge 23
- Dorchester 22
- Etobicoke 22
- Ingersoll 22
- North York 22
- Peterborough 22
- Willowdale 22
- Almonte 21
- Brampton 21
- Brant 21
- Brockville 21
- Ottawa 21
- Sioux Narrows 21
- Timmins 20
- Ancaster 19
- Oshawa 19
- Owen Sound 19
- Wellington County 19
- Bluewater 17
- East York 17
- Innisfil 17
- Parry Sound 17
- Quinte West 17
- Woodstock 17
- Burlington 16
- Barrie 15
- Delaware 15
- Shelburne 14
- Huron East 13
- Niagara Falls 12
- Orillia 12
- Petrolia 12
- South Huron 12
- St. Catharines 12
- Amherstburg 11
- Binbrook 11
- Lindsay 11
- Omemee 11
- Camlachie 10
- Renfrew 10
- Blyth 9
- Casselman 9
- Lambton Shores 9
- St. Thomas 9
- Wingham 9
- Aylmer 8
- Bourget 8
- Clarence-Rockland 8
- Fort Frances 8
- Greater Napanee 8
- Nestor Falls 8
- Skatepark 8
- Bells Corners 7
- Deseronto 7
- Gananoque 7
- Goderich 7
- Hanover 7
- Hawkesbury 7
- Napanee Downtown 7
- Nepean 7
- Norfolk County 7
- Simcoe 7
- Thorold 7
- Welland 7
- Wendover 7
- Angus 6
- Arnprior 6
- Carleton Place 6
- Kincardine 6
- Morrisburg 6
- Port Colborne 6
- Prescott 6
- Smiths Falls 6
- Bracebridge 5
- Cobourg 5
- Dryden 5
- Ear Falls 5
- Gravenhurst 5
- Huntsville 5
- Midland 5
- Perth 5
- Red Lake 5
- Wasaga Beach 5
- Atikokan 4
- Bancroft 4
- Collingwood 4
- Deep River 4
- Elliot Lake 4
- Englehart 4
- Espanola 4
- Greenstone 4
- Hearst 4
- Hornepayne 4
- Iroquois Falls 4
- Kapuskasing 4
- Kirkland Lake 4
- Little Current 4
- Marathon 4
- Mattawa 4
- Minden Hills 4
- Neebing 4
- Pembroke 4
- Petawawa 4
- Picton 4
- Powassan 4
- Prince Edward 4
- Rayside-Balfour 4
- South River 4
- Temiskaming Shores 4
- Thessalon 4
- Tobermory 4
AQI US, Metric