Pollutant concentrations for May 8, 2026, 9:00 am EDT

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Pollutant concentrations for May 8, 2026, 9:00 am EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 27Barrie graph for O3 4Barrie graph for PM2.5 5.1Barrie graph for NO2    
Belleville 34Belleville graph for O3 2Belleville graph for PM2.5 3Belleville graph for NO2    
Brampton 36Brampton graph for O3 4Brampton graph for PM2.5 5Brampton graph for NO2    
Brantford 33Brantford graph for O3 10Brantford graph for PM2.5 3.7Brantford graph for NO2    
Burlington 31Burlington graph for O3 4Burlington graph for PM2.5 7.1Burlington graph for NO2    
Chatham 26Chatham graph for O3 7Chatham graph for PM2.5 5Chatham graph for NO2    
Cornwall 30Cornwall graph for O3 2Cornwall graph for PM2.5 1.4Cornwall graph for NO2    
Dorset 37Dorset graph for O3 2Dorset graph for PM2.5      
Grand Bend 39Grand Bend graph for O3 7Grand Bend graph for PM2.5 1.8Grand Bend graph for NO2    
Guelph 35Guelph graph for O3 4Guelph graph for PM2.5 5.3Guelph graph for NO2    
Hamilton Downtown 27Hamilton Downtown graph for O3 5Hamilton Downtown graph for PM2.5 5.9Hamilton Downtown graph for NO2 0.3Hamilton Downtown graph for SO2 0.16Hamilton Downtown graph for CO
Hamilton Mountain 29Hamilton Mountain graph for O3 6Hamilton Mountain graph for PM2.5 3.8Hamilton Mountain graph for NO2 0.3Hamilton Mountain graph for SO2  
Hamilton West 26Hamilton West graph for O3 5Hamilton West graph for PM2.5 5.6Hamilton West graph for NO2    
Kingston 33Kingston graph for O3 2Kingston graph for PM2.5 2.4Kingston graph for NO2    
Kitchener 33Kitchener graph for O3 5Kitchener graph for PM2.5 6.6Kitchener graph for NO2    
London 32London graph for O3 9London graph for PM2.5 7.3London graph for NO2    
Milton 33Milton graph for O3 6Milton graph for PM2.5 9.1Milton graph for NO2 0.2Milton graph for SO2  
Mississauga 34Mississauga graph for O3 4Mississauga graph for PM2.5 5.2Mississauga graph for NO2    
Newmarket 37Newmarket graph for O3 3Newmarket graph for PM2.5 1.4Newmarket graph for NO2    
North Bay 31North Bay graph for O3 3North Bay graph for PM2.5 0.5North Bay graph for NO2    
Oakville 35Oakville graph for O3 4Oakville graph for PM2.5 5.8Oakville graph for NO2    
Oshawa 32Oshawa graph for O3 4Oshawa graph for PM2.5 3.3Oshawa graph for NO2    
Ottawa Downtown 28Ottawa Downtown graph for O3 2Ottawa Downtown graph for PM2.5 3.4Ottawa Downtown graph for NO2    
Parry Sound 38Parry Sound graph for O3 2Parry Sound graph for PM2.5 1Parry Sound graph for NO2    
Peterborough 31Peterborough graph for O3 3Peterborough graph for PM2.5 1.9Peterborough graph for NO2    
Port Stanley 37Port Stanley graph for O3 7Port Stanley graph for PM2.5 4.1Port Stanley graph for NO2    
Sarnia 25Sarnia graph for O3 11Sarnia graph for PM2.5 18.9Sarnia graph for NO2 0.3Sarnia graph for SO2  
Sault Ste. Marie 13Sault Ste. Marie graph for O3 7Sault Ste. Marie graph for PM2.5 11.9Sault Ste. Marie graph for NO2 0.1Sault Ste. Marie graph for SO2  
St. Catharines 30St. Catharines graph for O3 6St. Catharines graph for PM2.5 6St. Catharines graph for NO2    
Sudbury 28Sudbury graph for O3 4Sudbury graph for PM2.5 5.1Sudbury graph for NO2 0.1Sudbury graph for SO2  
Thunder Bay 12Thunder Bay graph for O3 9Thunder Bay graph for PM2.5 14.2Thunder Bay graph for NO2    
Tiverton 34Tiverton graph for O3 4Tiverton graph for PM2.5      
Toronto Downtown 34Toronto Downtown graph for O3 N/AToronto Downtown graph for PM2.5 12.5Toronto Downtown graph for NO2    
Toronto East 29Toronto East graph for O3 4Toronto East graph for PM2.5 11.4Toronto East graph for NO2    
Toronto North 33Toronto North graph for O3 5Toronto North graph for PM2.5 10.5Toronto North graph for NO2 0.1Toronto North graph for SO2  
Toronto West 26Toronto West graph for O3 5Toronto West graph for PM2.5 18.8Toronto West graph for NO2 0.1Toronto West graph for SO2 0.18Toronto West graph for CO
Windsor Downtown 30Windsor Downtown graph for O3 9Windsor Downtown graph for PM2.5 9.4Windsor Downtown graph for NO2 0.4Windsor Downtown graph for SO2 0.21Windsor Downtown graph for CO
Windsor West 29Windsor West graph for O3 9Windsor West graph for PM2.5 8.7Windsor West graph for NO2 0.3Windsor 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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