Pollutant concentrations for March 12, 2026, 5:00 pm EDT

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Pollutant concentrations for March 12, 2026, 5:00 pm EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 41Barrie graph for O3 3Barrie graph for PM2.5 1.2Barrie graph for NO2    
Belleville 42Belleville graph for O3 2Belleville graph for PM2.5 1.1Belleville graph for NO2    
Brampton 41Brampton graph for O3 2Brampton graph for PM2.5 0.8Brampton graph for NO2    
Brantford 39Brantford graph for O3 3Brantford graph for PM2.5 1Brantford graph for NO2    
Burlington N/ABurlington graph for O3 2Burlington graph for PM2.5 4Burlington graph for NO2    
Chatham 41Chatham graph for O3 3Chatham graph for PM2.5 1.7Chatham graph for NO2    
Cornwall 38Cornwall graph for O3 3Cornwall graph for PM2.5 1.1Cornwall graph for NO2    
Dorset N/ADorset graph for O3 N/ADorset graph for PM2.5      
Grand Bend 39Grand Bend graph for O3 3Grand Bend graph for PM2.5 0.5Grand Bend graph for NO2    
Guelph 40Guelph graph for O3 2Guelph graph for PM2.5 0.7Guelph graph for NO2    
Hamilton Downtown 38Hamilton Downtown graph for O3 3Hamilton Downtown graph for PM2.5 2.1Hamilton Downtown graph for NO2 0.2Hamilton Downtown graph for SO2 0.14Hamilton Downtown graph for CO
Hamilton Mountain 41Hamilton Mountain graph for O3 2Hamilton Mountain graph for PM2.5 1.3Hamilton Mountain graph for NO2 0Hamilton Mountain graph for SO2  
Hamilton West 37Hamilton West graph for O3 3Hamilton West graph for PM2.5 4.4Hamilton West graph for NO2    
Kingston 39Kingston graph for O3 3Kingston graph for PM2.5 1.8Kingston graph for NO2    
Kitchener 38Kitchener graph for O3 2Kitchener graph for PM2.5 1.2Kitchener graph for NO2    
London 38London graph for O3 3London graph for PM2.5 1.7London graph for NO2    
Milton 41Milton graph for O3 2Milton graph for PM2.5 0.4Milton graph for NO2 0.3Milton graph for SO2  
Mississauga 40Mississauga graph for O3 2Mississauga graph for PM2.5 1.6Mississauga graph for NO2    
Newmarket 41Newmarket graph for O3 2Newmarket graph for PM2.5 1.2Newmarket graph for NO2    
North Bay 38North Bay graph for O3 2North Bay graph for PM2.5 0.4North Bay graph for NO2    
Oakville 39Oakville graph for O3 2Oakville graph for PM2.5 0.9Oakville graph for NO2    
Oshawa 42Oshawa graph for O3 7Oshawa graph for PM2.5 0.3Oshawa graph for NO2    
Ottawa Downtown 36Ottawa Downtown graph for O3 3Ottawa Downtown graph for PM2.5 3.2Ottawa Downtown graph for NO2    
Parry Sound 42Parry Sound graph for O3 2Parry Sound graph for PM2.5 0.5Parry Sound graph for NO2    
Peterborough 43Peterborough graph for O3 3Peterborough graph for PM2.5 0.6Peterborough graph for NO2    
Port Stanley 39Port Stanley graph for O3 2Port Stanley graph for PM2.5 1.5Port Stanley graph for NO2    
Sarnia 39Sarnia graph for O3 3Sarnia graph for PM2.5 1.3Sarnia graph for NO2 0Sarnia graph for SO2  
Sault Ste. Marie 43Sault Ste. Marie graph for O3 2Sault Ste. Marie graph for PM2.5 2.5Sault Ste. Marie graph for NO2 0Sault Ste. Marie graph for SO2  
St. Catharines 41St. Catharines graph for O3 3St. Catharines graph for PM2.5 1.4St. Catharines graph for NO2    
Sudbury 40Sudbury graph for O3 2Sudbury graph for PM2.5 2.3Sudbury graph for NO2 0Sudbury graph for SO2  
Thunder Bay 35Thunder Bay graph for O3 4Thunder Bay graph for PM2.5 1.7Thunder Bay graph for NO2    
Tiverton 38Tiverton graph for O3 2Tiverton graph for PM2.5      
Toronto Downtown 29Toronto Downtown graph for O3 6Toronto Downtown graph for PM2.5 35.8Toronto Downtown graph for NO2    
Toronto East 37Toronto East graph for O3 3Toronto East graph for PM2.5 5.6Toronto East graph for NO2    
Toronto North 37Toronto North graph for O3 3Toronto North graph for PM2.5 4.2Toronto North graph for NO2 0Toronto North graph for SO2  
Toronto West 36Toronto West graph for O3 3Toronto West graph for PM2.5 7.5Toronto West graph for NO2 0Toronto West graph for SO2 0.16Toronto West graph for CO
Windsor Downtown 41Windsor Downtown graph for O3 3Windsor Downtown graph for PM2.5 4.3Windsor Downtown graph for NO2 0Windsor Downtown graph for SO2 0.17Windsor Downtown graph for CO
Windsor West 40Windsor West graph for O3 3Windsor West graph for PM2.5 3.1Windsor 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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