Pollutant concentrations for
July 9, 2025, 3:00 am EDT

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Pollutant concentrations for
July 9, 2025, 3:00 am EDT July 9, 2025, 3:00 am EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 10Barrie graph for O3 8Barrie graph for PM2.5 2.1Barrie graph for NO2    
Belleville 14Belleville graph for O3 7Belleville graph for PM2.5 6.7Belleville graph for NO2    
Brampton 18Brampton graph for O3 8Brampton graph for PM2.5 3.1Brampton graph for NO2    
Brantford 8Brantford graph for O3 9Brantford graph for PM2.5 3.2Brantford graph for NO2    
Burlington 9Burlington graph for O3 8Burlington graph for PM2.5 12.9Burlington graph for NO2    
Chatham 46Chatham graph for O3 15Chatham graph for PM2.5 3.7Chatham graph for NO2    
Cornwall 16Cornwall graph for O3 6Cornwall graph for PM2.5 2.3Cornwall graph for NO2    
Dorset 2Dorset graph for O3 6Dorset graph for PM2.5      
Grand Bend 15Grand Bend graph for O3 10Grand Bend graph for PM2.5 3.2Grand Bend graph for NO2    
Guelph 13Guelph graph for O3 8Guelph graph for PM2.5 1.8Guelph graph for NO2    
Hamilton Downtown 18Hamilton Downtown graph for O3 10Hamilton Downtown graph for PM2.5 3.3Hamilton Downtown graph for NO2 0.9Hamilton Downtown graph for SO2 0.18Hamilton Downtown graph for CO
Hamilton Mountain 17Hamilton Mountain graph for O3 10Hamilton Mountain graph for PM2.5 3.8Hamilton Mountain graph for NO2 0.8Hamilton Mountain graph for SO2  
Hamilton West 12Hamilton West graph for O3 9Hamilton West graph for PM2.5 8.2Hamilton West graph for NO2    
Kingston 20Kingston graph for O3 5Kingston graph for PM2.5 2.4Kingston graph for NO2    
Kitchener 12Kitchener graph for O3 10Kitchener graph for PM2.5 3.6Kitchener graph for NO2    
London 5London graph for O3 12London graph for PM2.5 6.4London graph for NO2    
Milton 17Milton graph for O3 8Milton graph for PM2.5 3.8Milton graph for NO2 0.3Milton graph for SO2  
Mississauga 12Mississauga graph for O3 8Mississauga graph for PM2.5 8.5Mississauga graph for NO2    
Newmarket 20Newmarket graph for O3 9Newmarket graph for PM2.5 2.6Newmarket graph for NO2    
North Bay 7North Bay graph for O3 6North Bay graph for PM2.5 3.8North Bay graph for NO2    
Oakville 15Oakville graph for O3 8Oakville graph for PM2.5 6Oakville graph for NO2    
Oshawa 6Oshawa graph for O3 7Oshawa graph for PM2.5 4.5Oshawa graph for NO2    
Ottawa Downtown 14Ottawa Downtown graph for O3 5Ottawa Downtown graph for PM2.5 3.4Ottawa Downtown graph for NO2    
Parry Sound 2Parry Sound graph for O3 8Parry Sound graph for PM2.5 7.1Parry Sound graph for NO2    
Peterborough 18Peterborough graph for O3 7Peterborough graph for PM2.5 2.7Peterborough graph for NO2    
Port Stanley 27Port Stanley graph for O3 18Port Stanley graph for PM2.5 2.4Port Stanley graph for NO2    
Sarnia 29Sarnia graph for O3 17Sarnia graph for PM2.5 10.4Sarnia graph for NO2 0.2Sarnia graph for SO2  
Sault Ste. Marie 18Sault Ste. Marie graph for O3 7Sault Ste. Marie graph for PM2.5 0.9Sault Ste. Marie graph for NO2 N/ASault Ste. Marie graph for SO2  
St. Catharines 27St. Catharines graph for O3 8St. Catharines graph for PM2.5 1.6St. Catharines graph for NO2    
Sudbury 17Sudbury graph for O3 12Sudbury graph for PM2.5 5.4Sudbury graph for NO2 0.4Sudbury graph for SO2  
Thunder Bay 6Thunder Bay graph for O3 7Thunder Bay graph for PM2.5 3.2Thunder Bay graph for NO2    
Tiverton 15Tiverton graph for O3 9Tiverton graph for PM2.5      
Toronto Downtown 17Toronto Downtown graph for O3 7Toronto Downtown graph for PM2.5 9Toronto Downtown graph for NO2    
Toronto East 14Toronto East graph for O3 6Toronto East graph for PM2.5 5.9Toronto East graph for NO2    
Toronto North 22Toronto North graph for O3 9Toronto North graph for PM2.5 3.9Toronto North graph for NO2 0.5Toronto North graph for SO2  
Toronto West 16Toronto West graph for O3 10Toronto West graph for PM2.5 8.6Toronto West graph for NO2 0.5Toronto West graph for SO2 0.19Toronto West graph for CO
Windsor Downtown 41Windsor Downtown graph for O3 19Windsor Downtown graph for PM2.5 5.8Windsor Downtown graph for NO2 0Windsor Downtown graph for SO2 0.24Windsor Downtown graph for CO
Windsor West 41Windsor West graph for O3 24Windsor West graph for PM2.5 2.6Windsor West graph for NO2 0Windsor West graph for SO2  

Order by station location (east to west)

Note: 
Ontario 1-hour AAQC for O3 = 80 ppb
Ontario 1-hour AAQC for NO2 = 200 ppb
Ontario 1-hour AAQC for SO2 = 40 ppb
Ontario 1-hour AAQC for CO = 30 ppm

Note: The pollutant concentrations on this web page are based on automatically polled data and have not undergone final verification.

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