Pollutant concentrations for
July 9, 2025, 5:00 am EDT

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Pollutant concentrations for
July 9, 2025, 5:00 am EDT July 9, 2025, 5:00 am EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 4Barrie graph for O3 9Barrie graph for PM2.5 6.4Barrie graph for NO2    
Belleville 14Belleville graph for O3 7Belleville graph for PM2.5 6.6Belleville graph for NO2    
Brampton 11Brampton graph for O3 8Brampton graph for PM2.5 5.1Brampton graph for NO2    
Brantford 9Brantford graph for O3 10Brantford graph for PM2.5 4.6Brantford graph for NO2    
Burlington 8Burlington graph for O3 8Burlington graph for PM2.5 10.5Burlington graph for NO2    
Chatham 42Chatham graph for O3 14Chatham graph for PM2.5 4.4Chatham graph for NO2    
Cornwall 9Cornwall graph for O3 7Cornwall graph for PM2.5 2.8Cornwall graph for NO2    
Dorset 1Dorset graph for O3 6Dorset graph for PM2.5      
Grand Bend 22Grand Bend graph for O3 12Grand Bend graph for PM2.5 3.3Grand Bend graph for NO2    
Guelph 7Guelph graph for O3 9Guelph graph for PM2.5 2.5Guelph graph for NO2    
Hamilton Downtown 15Hamilton Downtown graph for O3 10Hamilton Downtown graph for PM2.5 3.6Hamilton Downtown graph for NO2 0.6Hamilton Downtown graph for SO2 0.18Hamilton Downtown graph for CO
Hamilton Mountain 11Hamilton Mountain graph for O3 9Hamilton Mountain graph for PM2.5 4.4Hamilton Mountain graph for NO2 0.3Hamilton Mountain graph for SO2  
Hamilton West 4Hamilton West graph for O3 9Hamilton West graph for PM2.5 11.8Hamilton West graph for NO2    
Kingston 16Kingston graph for O3 6Kingston graph for PM2.5 2.4Kingston graph for NO2    
Kitchener 8Kitchener graph for O3 11Kitchener graph for PM2.5 4.5Kitchener graph for NO2    
London 9London graph for O3 13London graph for PM2.5 5.1London graph for NO2    
Milton 6Milton graph for O3 9Milton graph for PM2.5 11.6Milton graph for NO2 0.2Milton graph for SO2  
Mississauga 8Mississauga graph for O3 7Mississauga graph for PM2.5 6.3Mississauga graph for NO2    
Newmarket 15Newmarket graph for O3 10Newmarket graph for PM2.5 2.9Newmarket graph for NO2    
North Bay 4North Bay graph for O3 5North Bay graph for PM2.5 5.1North Bay graph for NO2    
Oakville 10Oakville graph for O3 9Oakville graph for PM2.5 6.5Oakville graph for NO2    
Oshawa 5Oshawa graph for O3 8Oshawa graph for PM2.5 3.4Oshawa graph for NO2    
Ottawa Downtown 5Ottawa Downtown graph for O3 5Ottawa Downtown graph for PM2.5 2.1Ottawa Downtown graph for NO2    
Parry Sound 8Parry Sound graph for O3 9Parry Sound graph for PM2.5 2.9Parry Sound graph for NO2    
Peterborough 14Peterborough graph for O3 7Peterborough graph for PM2.5 3.5Peterborough graph for NO2    
Port Stanley 12Port Stanley graph for O3 19Port Stanley graph for PM2.5 4Port Stanley graph for NO2    
Sarnia 32Sarnia graph for O3 19Sarnia graph for PM2.5 10.8Sarnia graph for NO2 0.5Sarnia graph for SO2  
Sault Ste. Marie 15Sault Ste. Marie graph for O3 7Sault Ste. Marie graph for PM2.5 0.4Sault Ste. Marie graph for NO2 N/ASault Ste. Marie graph for SO2  
St. Catharines 19St. Catharines graph for O3 10St. Catharines graph for PM2.5 3.2St. Catharines graph for NO2    
Sudbury 19Sudbury graph for O3 11Sudbury graph for PM2.5 3.5Sudbury graph for NO2 1.2Sudbury graph for SO2  
Thunder Bay 3Thunder Bay graph for O3 7Thunder Bay graph for PM2.5 2.2Thunder Bay graph for NO2    
Tiverton 17Tiverton graph for O3 10Tiverton graph for PM2.5      
Toronto Downtown 16Toronto Downtown graph for O3 8Toronto Downtown graph for PM2.5 8.8Toronto Downtown graph for NO2    
Toronto East 14Toronto East graph for O3 10Toronto East graph for PM2.5 9.7Toronto East graph for NO2    
Toronto North 19Toronto North graph for O3 8Toronto North graph for PM2.5 2.8Toronto North graph for NO2 0.4Toronto North graph for SO2  
Toronto West 9Toronto West graph for O3 9Toronto West graph for PM2.5 13.2Toronto West graph for NO2 0.1Toronto West graph for SO2 N/AToronto West graph for CO
Windsor Downtown 33Windsor Downtown graph for O3 19Windsor Downtown graph for PM2.5 10.8Windsor Downtown graph for NO2 0Windsor Downtown graph for SO2 0.27Windsor Downtown graph for CO
Windsor West 33Windsor West graph for O3 25Windsor West graph for PM2.5 9.8Windsor 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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