Pollutant concentrations for May 20, 2026, 5:00 pm EDT

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Pollutant concentrations for May 20, 2026, 5:00 pm EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Thunder Bay 27Thunder Bay graph for O3 1Thunder Bay graph for PM2.5 1.3Thunder Bay graph for NO2    
Sault Ste. Marie 33Sault Ste. Marie graph for O3 1Sault Ste. Marie graph for PM2.5 1.3Sault Ste. Marie graph for NO2 0Sault Ste. Marie graph for SO2  
Windsor West 24Windsor West graph for O3 3Windsor West graph for PM2.5 2.8Windsor West graph for NO2 0.2Windsor West graph for SO2  
Windsor Downtown 25Windsor Downtown graph for O3 3Windsor Downtown graph for PM2.5 3Windsor Downtown graph for NO2 0.2Windsor Downtown graph for SO2 0.17Windsor Downtown graph for CO
Sarnia 30Sarnia graph for O3 1Sarnia graph for PM2.5 1.8Sarnia graph for NO2 0.1Sarnia graph for SO2  
Chatham 29Chatham graph for O3 3Chatham graph for PM2.5 2.2Chatham graph for NO2    
Grand Bend 34Grand Bend graph for O3 0Grand Bend graph for PM2.5 0.9Grand Bend graph for NO2    
Tiverton 30Tiverton graph for O3 0Tiverton graph for PM2.5      
London 38London graph for O3 2London graph for PM2.5 2.5London graph for NO2    
Port Stanley 34Port Stanley graph for O3 2Port Stanley graph for PM2.5 2.6Port Stanley graph for NO2    
Sudbury 35Sudbury graph for O3 1Sudbury graph for PM2.5 1.3Sudbury graph for NO2 0Sudbury graph for SO2  
Kitchener 36Kitchener graph for O3 1Kitchener graph for PM2.5 2.3Kitchener graph for NO2    
Brantford 38Brantford graph for O3 2Brantford graph for PM2.5 1.7Brantford graph for NO2    
Guelph 35Guelph graph for O3 1Guelph graph for PM2.5 1.9Guelph graph for NO2    
Parry Sound 21Parry Sound graph for O3 1Parry Sound graph for PM2.5 0.9Parry Sound graph for NO2    
Hamilton West 38Hamilton West graph for O3 2Hamilton West graph for PM2.5 3.5Hamilton West graph for NO2    
Hamilton Mountain 40Hamilton Mountain graph for O3 2Hamilton Mountain graph for PM2.5 2.7Hamilton Mountain graph for NO2 0Hamilton Mountain graph for SO2  
Milton 39Milton graph for O3 2Milton graph for PM2.5 0.5Milton graph for NO2 0.5Milton graph for SO2  
Hamilton Downtown 36Hamilton Downtown graph for O3 2Hamilton Downtown graph for PM2.5 3.1Hamilton Downtown graph for NO2 0Hamilton Downtown graph for SO2 0.17Hamilton Downtown graph for CO
Burlington 36Burlington graph for O3 1Burlington graph for PM2.5 5.2Burlington graph for NO2    
Brampton 37Brampton graph for O3 1Brampton graph for PM2.5 1.5Brampton graph for NO2    
Barrie 24Barrie graph for O3 1Barrie graph for PM2.5 1Barrie graph for NO2    
Oakville 36Oakville graph for O3 1Oakville graph for PM2.5 1.6Oakville graph for NO2    
Mississauga 37Mississauga graph for O3 1Mississauga graph for PM2.5 1.8Mississauga graph for NO2    
Toronto West 27Toronto West graph for O3 2Toronto West graph for PM2.5 8.5Toronto West graph for NO2 0Toronto West graph for SO2 0.14Toronto West graph for CO
Newmarket 29Newmarket graph for O3 1Newmarket graph for PM2.5 1.7Newmarket graph for NO2    
Toronto North 31Toronto North graph for O3 1Toronto North graph for PM2.5 2.5Toronto North graph for NO2 0Toronto North graph for SO2  
North Bay 29North Bay graph for O3 0North Bay graph for PM2.5 0North Bay graph for NO2    
Toronto Downtown 29Toronto Downtown graph for O3 5Toronto Downtown graph for PM2.5 13.2Toronto Downtown graph for NO2    
Toronto East 30Toronto East graph for O3 2Toronto East graph for PM2.5 4.8Toronto East graph for NO2    
St. Catharines 35St. Catharines graph for O3 2St. Catharines graph for PM2.5 2.7St. Catharines graph for NO2    
Dorset 24Dorset graph for O3 2Dorset graph for PM2.5      
Oshawa 34Oshawa graph for O3 1Oshawa graph for PM2.5 0.8Oshawa graph for NO2    
Peterborough 24Peterborough graph for O3 1Peterborough graph for PM2.5 0.7Peterborough graph for NO2    
Belleville 28Belleville graph for O3 1Belleville graph for PM2.5 1.4Belleville graph for NO2    
Kingston 33Kingston graph for O3 1Kingston graph for PM2.5 1.2Kingston graph for NO2    
Ottawa Downtown 22Ottawa Downtown graph for O3 1Ottawa Downtown graph for PM2.5 1.4Ottawa Downtown graph for NO2    
Cornwall 34Cornwall graph for O3 2Cornwall graph for PM2.5 0.8Cornwall graph for NO2    

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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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