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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 | Mississauga | 58 |
| 2 | Port Stanley | 57 |
| 3 | Niagara Falls | 55 |
| 4 | Oakville | 52 |
| 5 | London | 47 |
| 6 | Cambridge | 45 |
| 7 | Woodstock | 44 |
| 8 | Fort Erie | 43 |
| 9 | Kitchener | 42 |
| 10 | Milton | 40 |
(local time)
SEE WORLD AQI RANKINGAIR QUALITY DATA CONTRIBUTORS
93 Contributors
See all
LIVE AQI CITY RANKING
Real-time Ontario
Cleanest city ranking
| # | city | US AQI |
|---|---|---|
| 1 | Scarborough | 2 |
| 2 | Kirkland Lake | 5 |
| 3 | Orillia | 6 |
| 4 | Timmins | 6 |
| 5 | Quinte West | 7 |
| 6 | Sudbury | 8 |
| 7 | Ottawa | 11 |
| 8 | Cornwall | 12 |
| 9 | Renfrew | 13 |
| 10 | Uxbridge | 13 |
(local time)
SEE WORLD AQI RANKING
3D animated air pollution map
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Unhealthy for sensitive groups
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The latest air quality news and resources.
Ontario air quality data attribution
93Contributors
- 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
4 Non-profit organization Contributors
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
- VB
1 station
- randalljhoward
1 station
CS2 stations
- **
1 station
- Bijan
1 station
- Libby
1 station
- Mark Douglas Wessel
1 station
- JayDee
1 station
- Keevabay
1 station
23 Individual Contributors
62 Anonymous contributors62 stations
62 Anonymous Contributors
Which is the most polluted city in Ontario?
- Mississauga 58
- Port Stanley 57
- Niagara Falls 55
- Oakville 52
- London 47
- Cambridge 45
- Woodstock 44
- Fort Erie 43
- Kitchener 42
- East York 40
- Milton 40
- Pickering 40
- Picton 40
- Cobourg 39
- Concord 39
- North York 39
- Prince Edward 39
- Vaughan 39
- Willowdale 39
- Etobicoke 38
- Keswick 38
- Thorold 38
- Toronto 38
- Waterloo 38
- Angus 37
- Barrie 37
- Egbert 37
- Wasaga Beach 37
- Welland 37
- Binbrook 36
- Collingwood 36
- Midland 36
- Niagara on the Lake 36
- Owen Sound 36
- Port Colborne 36
- Richmond Hill 36
- Tobermory 36
- Ancaster 35
- Lindsay 35
- Markham 35
- Omemee 35
- Deseronto 34
- Orangeville 34
- Shelburne 34
- Wellington County 34
- Hanover 33
- Kincardine 33
- Simcoe 33
- Brant 32
- Gravenhurst 32
- Norfolk County 32
- Paris 32
- Brampton 31
- Napanee Downtown 31
- North Perth 31
- Windsor 31
- Wingham 31
- Blyth 30
- Bracebridge 30
- Chatham 30
- Greater Napanee 30
- Sarnia 30
- Skatepark 30
- Bonner Lake 29
- Burlington 29
- Gananoque 29
- Huron East 29
- North Bay 29
- Stratford 29
- Thessalon 29
- Tiverton 29
- Goderich 28
- Little Current 28
- Ingersoll 27
- Parry Sound 27
- Algoma 26
- Dorset 26
- Hamilton 26
- Oshawa 26
- Newmarket 25
- Sault Ste Marie 25
- South Huron 25
- Aylmer 24
- Delaware 24
- Dorchester 24
- Kingston 24
- Minden Hills 24
- Peterborough 24
- Belleville 23
- Elliot Lake 23
- Lambton Shores 23
- St. Thomas 23
- Innisfil 22
- Bluewater 21
- Camlachie 21
- Espanola 21
- Grand Bend 21
- Huntsville 21
- Petrolia 21
- St. Catharines 21
- Guelph 20
- Walpole Island 20
- Coldwater 19
- Experimental Lakes 19
- Pickle Lake 19
- Sioux Narrows 19
- Amherstburg 17
- Brantford 17
- Brockville 17
- Thunder Bay 15
- Ajax 14
- Almonte 14
- South River 14
- Bancroft 13
- Rayside-Balfour 13
- Renfrew 13
- Uxbridge 13
- Cornwall 12
- Prescott 12
- Marathon 11
- Morrisburg 11
- Ottawa 11
- Powassan 11
- Nestor Falls 10
- Bourget 9
- Casselman 9
- Fort Frances 9
- Hawkesbury 9
- Hearst 9
- Perth 9
- Smiths Falls 9
- Wendover 9
- Carleton Place 8
- Clarence-Rockland 8
- Ear Falls 8
- Hornepayne 8
- Mattawa 8
- Nepean 8
- Sudbury 8
- Arnprior 7
- Bells Corners 7
- Deep River 7
- Dryden 7
- Pembroke 7
- Petawawa 7
- Quinte West 7
- Red Lake 7
- Greenstone 6
- Kapuskasing 6
- Neebing 6
- Orillia 6
- Timmins 6
- Atikokan 5
- Englehart 5
- Kirkland Lake 5
- Temiskaming Shores 5
- Iroquois Falls 4
- Scarborough 2
AQI US, Metric