Pollutant concentrations for March 21, 2026, 7:00 pm EDT

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Pollutant concentrations for March 21, 2026, 7:00 pm EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 36Barrie graph for O3 3Barrie graph for PM2.5 2.6Barrie graph for NO2    
Belleville 37Belleville graph for O3 5Belleville graph for PM2.5 1.4Belleville graph for NO2    
Brampton 36Brampton graph for O3 5Brampton graph for PM2.5 5.4Brampton graph for NO2    
Brantford 34Brantford graph for O3 7Brantford graph for PM2.5 1Brantford graph for NO2    
Burlington 40Burlington graph for O3 3Burlington graph for PM2.5 1.7Burlington graph for NO2    
Chatham 35Chatham graph for O3 8Chatham graph for PM2.5 3.8Chatham graph for NO2    
Cornwall 43Cornwall graph for O3 4Cornwall graph for PM2.5 2.2Cornwall graph for NO2    
Dorset 36Dorset graph for O3 2Dorset graph for PM2.5      
Grand Bend 30Grand Bend graph for O3 11Grand Bend graph for PM2.5 2.5Grand Bend graph for NO2    
Guelph 37Guelph graph for O3 6Guelph graph for PM2.5 3.7Guelph graph for NO2    
Hamilton Downtown 31Hamilton Downtown graph for O3 6Hamilton Downtown graph for PM2.5 8Hamilton Downtown graph for NO2 1.5Hamilton Downtown graph for SO2 0.19Hamilton Downtown graph for CO
Hamilton Mountain 33Hamilton Mountain graph for O3 6Hamilton Mountain graph for PM2.5 5.4Hamilton Mountain graph for NO2 0.5Hamilton Mountain graph for SO2  
Hamilton West 29Hamilton West graph for O3 6Hamilton West graph for PM2.5 11.6Hamilton West graph for NO2    
Kingston 38Kingston graph for O3 5Kingston graph for PM2.5 1.3Kingston graph for NO2    
Kitchener 34Kitchener graph for O3 7Kitchener graph for PM2.5 4.6Kitchener graph for NO2    
London 33London graph for O3 9London graph for PM2.5 4.3London graph for NO2    
Milton 38Milton graph for O3 5Milton graph for PM2.5 1.4Milton graph for NO2 0.2Milton graph for SO2  
Mississauga 37Mississauga graph for O3 4Mississauga graph for PM2.5 2.3Mississauga graph for NO2    
Newmarket 31Newmarket graph for O3 7Newmarket graph for PM2.5 7.5Newmarket graph for NO2    
North Bay 38North Bay graph for O3 3North Bay graph for PM2.5 1.1North Bay graph for NO2    
Oakville 37Oakville graph for O3 3Oakville graph for PM2.5 2.4Oakville graph for NO2    
Oshawa 33Oshawa graph for O3 6Oshawa graph for PM2.5 1.7Oshawa graph for NO2    
Ottawa Downtown 37Ottawa Downtown graph for O3 3Ottawa Downtown graph for PM2.5 2.9Ottawa Downtown graph for NO2    
Parry Sound 37Parry Sound graph for O3 2Parry Sound graph for PM2.5 2.7Parry Sound graph for NO2    
Peterborough 34Peterborough graph for O3 5Peterborough graph for PM2.5 2.7Peterborough graph for NO2    
Port Stanley 37Port Stanley graph for O3 6Port Stanley graph for PM2.5 2.6Port Stanley graph for NO2    
Sarnia 31Sarnia graph for O3 12Sarnia graph for PM2.5 4.7Sarnia graph for NO2 0.1Sarnia graph for SO2  
Sault Ste. Marie 35Sault Ste. Marie graph for O3 1Sault Ste. Marie graph for PM2.5 1.1Sault Ste. Marie graph for NO2 0.1Sault Ste. Marie graph for SO2  
St. Catharines 36St. Catharines graph for O3 4St. Catharines graph for PM2.5 2.2St. Catharines graph for NO2    
Sudbury 37Sudbury graph for O3 3Sudbury graph for PM2.5 4.4Sudbury graph for NO2 0.1Sudbury graph for SO2  
Thunder Bay 33Thunder Bay graph for O3 1Thunder Bay graph for PM2.5 2.6Thunder Bay graph for NO2    
Tiverton 32Tiverton graph for O3 5Tiverton graph for PM2.5      
Toronto Downtown 17Toronto Downtown graph for O3 7Toronto Downtown graph for PM2.5 43.7Toronto Downtown graph for NO2    
Toronto East 34Toronto East graph for O3 4Toronto East graph for PM2.5 3.8Toronto East graph for NO2    
Toronto North 32Toronto North graph for O3 7Toronto North graph for PM2.5 5.3Toronto North graph for NO2 0Toronto North graph for SO2  
Toronto West 30Toronto West graph for O3 6Toronto West graph for PM2.5 8.7Toronto West graph for NO2 0Toronto West graph for SO2 0.16Toronto West graph for CO
Windsor Downtown 35Windsor Downtown graph for O3 7Windsor Downtown graph for PM2.5 2.8Windsor Downtown graph for NO2 0Windsor Downtown graph for SO2 0.09Windsor Downtown graph for CO
Windsor West 35Windsor West graph for O3 6Windsor West graph for PM2.5 2.4Windsor 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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