Pollutant concentrations for March 21, 2026, 4:00 pm EDT

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Pollutant concentrations for March 21, 2026, 4:00 pm EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 36Barrie graph for O3 2Barrie graph for PM2.5 0.5Barrie graph for NO2    
Belleville 38Belleville graph for O3 5Belleville graph for PM2.5 1.4Belleville graph for NO2    
Brampton 39Brampton graph for O3 6Brampton graph for PM2.5 2.7Brampton graph for NO2    
Brantford 35Brantford graph for O3 6Brantford graph for PM2.5 1.2Brantford graph for NO2    
Burlington 39Burlington graph for O3 5Burlington graph for PM2.5 4.1Burlington graph for NO2    
Chatham 32Chatham graph for O3 9Chatham graph for PM2.5 3Chatham graph for NO2    
Cornwall 44Cornwall graph for O3 4Cornwall graph for PM2.5 0.5Cornwall graph for NO2    
Dorset 40Dorset graph for O3 2Dorset graph for PM2.5      
Grand Bend 31Grand Bend graph for O3 7Grand Bend graph for PM2.5 2Grand Bend graph for NO2    
Guelph 37Guelph graph for O3 5Guelph graph for PM2.5 3.2Guelph graph for NO2    
Hamilton Downtown 34Hamilton Downtown graph for O3 7Hamilton Downtown graph for PM2.5 6.9Hamilton Downtown graph for NO2 9.5Hamilton Downtown graph for SO2 0.18Hamilton Downtown graph for CO
Hamilton Mountain 40Hamilton Mountain graph for O3 6Hamilton Mountain graph for PM2.5 3.3Hamilton Mountain graph for NO2 0.8Hamilton Mountain graph for SO2  
Hamilton West 31Hamilton West graph for O3 6Hamilton West graph for PM2.5 11.2Hamilton West graph for NO2    
Kingston 40Kingston graph for O3 5Kingston graph for PM2.5 1.8Kingston graph for NO2    
Kitchener 35Kitchener graph for O3 7Kitchener graph for PM2.5 3.3Kitchener graph for NO2    
London 30London graph for O3 10London graph for PM2.5 2.9London graph for NO2    
Milton 42Milton graph for O3 5Milton graph for PM2.5 0.5Milton graph for NO2 0.4Milton graph for SO2  
Mississauga 37Mississauga graph for O3 5Mississauga graph for PM2.5 3.8Mississauga graph for NO2    
Newmarket 36Newmarket graph for O3 5Newmarket graph for PM2.5 2.6Newmarket graph for NO2    
North Bay 37North Bay graph for O3 4North Bay graph for PM2.5 0.4North Bay graph for NO2    
Oakville 39Oakville graph for O3 5Oakville graph for PM2.5 1.5Oakville graph for NO2    
Oshawa 34Oshawa graph for O3 5Oshawa graph for PM2.5 2.6Oshawa graph for NO2    
Ottawa Downtown 38Ottawa Downtown graph for O3 3Ottawa Downtown graph for PM2.5 1.4Ottawa Downtown graph for NO2    
Parry Sound 40Parry Sound graph for O3 1Parry Sound graph for PM2.5 0.9Parry Sound graph for NO2    
Peterborough 35Peterborough graph for O3 4Peterborough graph for PM2.5 1.4Peterborough graph for NO2    
Port Stanley 38Port Stanley graph for O3 7Port Stanley graph for PM2.5 2.9Port Stanley graph for NO2    
Sarnia 34Sarnia graph for O3 7Sarnia graph for PM2.5 3.9Sarnia graph for NO2 0.1Sarnia graph for SO2  
Sault Ste. Marie 35Sault Ste. Marie graph for O3 1Sault Ste. Marie graph for PM2.5 1.6Sault Ste. Marie graph for NO2 0Sault Ste. Marie graph for SO2  
St. Catharines 37St. Catharines graph for O3 5St. Catharines graph for PM2.5 1.6St. Catharines graph for NO2    
Sudbury 37Sudbury graph for O3 2Sudbury graph for PM2.5 4.4Sudbury graph for NO2 0.2Sudbury graph for SO2  
Thunder Bay 35Thunder Bay graph for O3 2Thunder Bay graph for PM2.5 3.1Thunder Bay graph for NO2    
Tiverton 38Tiverton graph for O3 4Tiverton graph for PM2.5      
Toronto Downtown 26Toronto Downtown graph for O3 7Toronto Downtown graph for PM2.5 27.4Toronto Downtown graph for NO2    
Toronto East 34Toronto East graph for O3 7Toronto East graph for PM2.5 3.9Toronto East graph for NO2    
Toronto North 33Toronto North graph for O3 9Toronto North graph for PM2.5 5.1Toronto North graph for NO2 0Toronto North graph for SO2  
Toronto West 37Toronto West graph for O3 5Toronto West graph for PM2.5 2.4Toronto West graph for NO2 0Toronto West graph for SO2 0.13Toronto West graph for CO
Windsor Downtown 35Windsor Downtown graph for O3 6Windsor Downtown graph for PM2.5 2.5Windsor Downtown graph for NO2 0Windsor Downtown graph for SO2 0.11Windsor Downtown graph for CO
Windsor West 34Windsor West graph for O3 6Windsor West graph for PM2.5 2.5Windsor 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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