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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 | Sudbury | 68 |
| 2 | Innisfil | 55 |
| 3 | Owen Sound | 55 |
| 4 | Tiverton | 55 |
| 5 | Milton | 54 |
| 6 | North Bay | 54 |
| 7 | Richmond Hill | 53 |
| 8 | Wellington County | 53 |
| 9 | Kitchener | 50 |
| 10 | Newmarket | 50 |
(local time)
SEE WORLD AQI RANKINGAIR QUALITY DATA CONTRIBUTORS
92 Contributors
See all
LIVE AQI CITY RANKING
Real-time Ontario
Cleanest city ranking
| # | city | US AQI |
|---|---|---|
| 1 | Sault Ste Marie | 3 |
| 2 | Almonte | 12 |
| 3 | Renfrew | 14 |
| 4 | Quinte West | 17 |
| 5 | Sioux Narrows | 19 |
| 6 | Brockville | 21 |
| 7 | Peterborough | 24 |
| 8 | Ajax | 25 |
| 9 | Cornwall | 25 |
| 10 | Thunder Bay | 25 |
(local time)
SEE WORLD AQI RANKING
3D animated air pollution map
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Unhealthy for sensitive groups
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News
The latest air quality news and resources.
Ontario air quality data attribution
92Contributors
- Hamilton Air Monitoring Network - HAMN
8 stations
- Township of SNNF
1 station
3 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
60 Anonymous contributors60 stations
60 Anonymous Contributors
Which is the most polluted city in Ontario?
- Sudbury 68
- Innisfil 55
- Owen Sound 55
- Tiverton 55
- Milton 54
- North Bay 54
- Richmond Hill 53
- Wellington County 53
- Ancaster 52
- Etobicoke 52
- Binbrook 51
- Orangeville 51
- Amherstburg 50
- Kitchener 50
- Newmarket 50
- Shelburne 50
- Concord 49
- East York 49
- Egbert 49
- North York 49
- Willowdale 49
- Angus 48
- Cambridge 48
- Collingwood 48
- Oakville 48
- Brant 47
- Keswick 47
- Paris 47
- Wasaga Beach 47
- Barrie 46
- Gravenhurst 46
- Hamilton 46
- Guelph 45
- Midland 45
- Norfolk County 45
- Port Stanley 45
- Simcoe 45
- Walpole Island 45
- Bracebridge 44
- Hanover 44
- Huron East 44
- Ingersoll 44
- North Perth 44
- Pickering 44
- Powassan 44
- South River 44
- Stratford 44
- Aylmer 43
- Burlington 43
- Dorchester 43
- Huntsville 43
- Kincardine 43
- Iroquois Falls 42
- Markham 42
- St. Thomas 42
- Thorold 42
- Bluewater 41
- Blyth 41
- Parry Sound 41
- Petrolia 41
- Rayside-Balfour 41
- South Huron 41
- Toronto 41
- Welland 41
- Wingham 41
- Brampton 40
- Camlachie 40
- Goderich 40
- Lambton Shores 40
- Lindsay 40
- Port Colborne 40
- Woodstock 40
- Delaware 39
- Espanola 39
- Little Current 39
- Minden Hills 39
- Omemee 39
- Orillia 39
- Tobermory 39
- London 38
- Waterloo 38
- Brantford 37
- Grand Bend 37
- Sarnia 37
- Vaughan 37
- Elliot Lake 36
- Mississauga 36
- Windsor 36
- Deep River 35
- Mattawa 35
- Pembroke 35
- Petawawa 35
- Arnprior 34
- Englehart 34
- Thessalon 34
- Chatham 33
- Cobourg 33
- Kingston 33
- Niagara on the Lake 33
- Temiskaming Shores 33
- Bancroft 31
- Coldwater 31
- Prince Edward 30
- Scarborough 30
- Uxbridge 30
- Dorset 29
- Picton 29
- St. Catharines 29
- Algoma 28
- Deseronto 28
- Niagara Falls 28
- Oshawa 28
- Ottawa 28
- Carleton Place 27
- Greater Napanee 27
- Napanee Downtown 27
- Skatepark 27
- Timmins 27
- Belleville 26
- Bells Corners 26
- Fort Erie 26
- Perth 26
- Ajax 25
- Cornwall 25
- Thunder Bay 25
- Peterborough 24
- Pickle Lake 24
- Smiths Falls 24
- Gananoque 23
- Nepean 23
- Brockville 21
- Bonner Lake 20
- Prescott 19
- Sioux Narrows 19
- Clarence-Rockland 17
- Quinte West 17
- Experimental Lakes 16
- Hawkesbury 16
- Wendover 16
- Bourget 15
- Casselman 15
- Morrisburg 15
- Renfrew 14
- Almonte 12
- Kapuskasing 11
- Hearst 6
- Hornepayne 5
- Atikokan 4
- Dryden 4
- Ear Falls 4
- Fort Frances 4
- Greenstone 4
- Kirkland Lake 4
- Marathon 4
- Neebing 4
- Nestor Falls 4
- Red Lake 4
- Sault Ste Marie 3
AQI US, Metric