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Air quality in Ontario
Air quality index (AQI) and PM2.5 air pollution in Ontario
LIVE AQI CITY RANKING
Real-time Ontario
Most polluted city ranking
| # | city | US AQI |
|---|---|---|
| 1 | Sault Ste Marie | 55 |
| 2 | Fort Erie | 37 |
| 3 | Oakville | 36 |
| 4 | Chatham | 33 |
| 5 | Kingston | 33 |
| 6 | Ottawa | 33 |
| 7 | North Bay | 32 |
| 8 | Thunder Bay | 32 |
| 9 | Windsor | 32 |
| 10 | Belleville | 31 |
(local time)
SEE WORLD AQI RANKINGAIR QUALITY DATA CONTRIBUTORS
95 Contributors
See all
LIVE AQI CITY RANKING
Real-time Ontario
Cleanest city ranking
| # | city | US AQI |
|---|---|---|
| 1 | Brockville | 8 |
| 2 | Sudbury | 14 |
| 3 | Waterloo | 14 |
| 4 | Almonte | 16 |
| 5 | Burlington | 16 |
| 6 | Timmins | 16 |
| 7 | Cornwall | 17 |
| 8 | Parry Sound | 17 |
| 9 | Peterborough | 17 |
| 10 | Renfrew | 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
8 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
- Kevin Damen
1 station
MikoAirOne1 station
- Anonymous
1 station
- Jim Guillet
1 station
- bsumm
1 station
Chris Fournier1 station
Slyyy1 station
JackB1 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
25 Individual Contributors
62 Anonymous contributors62 stations
62 Anonymous Contributors
Which is the most polluted city in Ontario?
- Sault Ste Marie 55
- Amherstburg 53
- Walpole Island 49
- Camlachie 44
- Petrolia 44
- Kincardine 42
- Goderich 40
- Lambton Shores 40
- Grand Bend 38
- Hanover 38
- Blyth 37
- Delaware 37
- Fort Erie 37
- Huron East 37
- South Huron 37
- Wingham 37
- Oakville 36
- Aylmer 35
- Collingwood 35
- Neebing 35
- North Perth 35
- St. Thomas 35
- Angus 34
- Dorchester 34
- Ingersoll 34
- Paris 34
- Shelburne 34
- Stratford 34
- Wasaga Beach 34
- Brant 33
- Chatham 33
- Kingston 33
- Norfolk County 33
- Orangeville 33
- Ottawa 33
- Simcoe 33
- Algoma 32
- Egbert 32
- North Bay 32
- Thunder Bay 32
- Windsor 32
- Belleville 31
- Bonner Lake 31
- Cambridge 31
- Fort Frances 31
- Port Stanley 31
- Sarnia 31
- Tiverton 31
- Tobermory 31
- Newmarket 30
- Experimental Lakes 29
- London 29
- Midland 29
- Brampton 28
- Concord 28
- Kitchener 28
- Marathon 28
- Owen Sound 28
- St. Catharines 28
- Vaughan 28
- Ancaster 27
- Bluewater 27
- Etobicoke 27
- Keswick 27
- North York 27
- Thessalon 27
- Willowdale 27
- East York 26
- Guelph 26
- Markham 26
- Pickle Lake 26
- Barrie 25
- Brantford 25
- Binbrook 24
- Hamilton 24
- Hawkesbury 24
- Innisfil 24
- Greenstone 22
- Pickering 22
- Wellington County 22
- Ajax 21
- Coldwater 21
- Elliot Lake 21
- Little Current 21
- Mississauga 21
- Niagara on the Lake 21
- Orillia 21
- Richmond Hill 21
- Toronto 21
- Uxbridge 21
- Woodstock 21
- Milton 20
- Quinte West 20
- Sioux Narrows 20
- Gravenhurst 19
- Niagara Falls 19
- Wendover 19
- Oshawa 18
- Scarborough 18
- Thorold 18
- Bracebridge 17
- Clarence-Rockland 17
- Cobourg 17
- Cornwall 17
- Dryden 17
- Espanola 17
- Mattawa 17
- Nestor Falls 17
- Parry Sound 17
- Peterborough 17
- Renfrew 17
- Welland 17
- Almonte 16
- Atikokan 16
- Burlington 16
- Lindsay 16
- Omemee 16
- Port Colborne 16
- Rayside-Balfour 16
- South River 16
- Timmins 16
- Bancroft 15
- Bourget 15
- Deep River 15
- Deseronto 15
- Ear Falls 15
- Greater Napanee 15
- Hornepayne 15
- Huntsville 15
- Minden Hills 15
- Napanee Downtown 15
- Pembroke 15
- Perth 15
- Petawawa 15
- Picton 15
- Powassan 15
- Prince Edward 15
- Red Lake 15
- Skatepark 15
- Arnprior 14
- Bells Corners 14
- Carleton Place 14
- Casselman 14
- Dorset 14
- Gananoque 14
- Hearst 14
- Morrisburg 14
- Nepean 14
- Prescott 14
- Smiths Falls 14
- Sudbury 14
- Waterloo 14
- Temiskaming Shores 13
- Englehart 12
- Kapuskasing 11
- Brockville 8
- Iroquois Falls 7
- Kirkland Lake 4
AQI US, Metric