Pollutant concentrations for July 4, 2026, 1:00 pm EDT

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Pollutant concentrations for July 4, 2026, 1:00 pm EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 33Barrie graph for O3 6Barrie graph for PM2.5 1.1Barrie graph for NO2    
Belleville 30Belleville graph for O3 6Belleville graph for PM2.5 2.6Belleville graph for NO2    
Brampton 26Brampton graph for O3 4Brampton graph for PM2.5 2Brampton graph for NO2    
Brantford 42Brantford graph for O3 6Brantford graph for PM2.5 1Brantford graph for NO2    
Burlington N/ABurlington graph for O3 N/ABurlington graph for PM2.5 N/ABurlington graph for NO2    
Chatham 51Chatham graph for O3 4Chatham graph for PM2.5 0.8Chatham graph for NO2    
Cornwall 32Cornwall graph for O3 10Cornwall graph for PM2.5 0.5Cornwall graph for NO2    
Dorset 23Dorset graph for O3 6Dorset graph for PM2.5      
Grand Bend 34Grand Bend graph for O3 6Grand Bend graph for PM2.5 1.4Grand Bend graph for NO2    
Guelph 26Guelph graph for O3 6Guelph graph for PM2.5 1.7Guelph graph for NO2    
Hamilton Downtown 29Hamilton Downtown graph for O3 6Hamilton Downtown graph for PM2.5 2.7Hamilton Downtown graph for NO2 0Hamilton Downtown graph for SO2 0.18Hamilton Downtown graph for CO
Hamilton Mountain 38Hamilton Mountain graph for O3 7Hamilton Mountain graph for PM2.5 2.2Hamilton Mountain graph for NO2 0.1Hamilton Mountain graph for SO2  
Hamilton West 32Hamilton West graph for O3 8Hamilton West graph for PM2.5 3.1Hamilton West graph for NO2    
Kingston 27Kingston graph for O3 9Kingston graph for PM2.5 1.6Kingston graph for NO2    
Kitchener 32Kitchener graph for O3 7Kitchener graph for PM2.5 2.2Kitchener graph for NO2    
London 46London graph for O3 5London graph for PM2.5 1.1London graph for NO2    
Milton 27Milton graph for O3 9Milton graph for PM2.5 1.6Milton graph for NO2 0.2Milton graph for SO2  
Mississauga 23Mississauga graph for O3 5Mississauga graph for PM2.5 2.6Mississauga graph for NO2    
Newmarket 39Newmarket graph for O3 6Newmarket graph for PM2.5 1.5Newmarket graph for NO2    
North Bay 31North Bay graph for O3 8North Bay graph for PM2.5 0North Bay graph for NO2    
Oakville 25Oakville graph for O3 8Oakville graph for PM2.5 2.6Oakville graph for NO2    
Oshawa 24Oshawa graph for O3 6Oshawa graph for PM2.5 5.4Oshawa graph for NO2    
Ottawa Downtown 32Ottawa Downtown graph for O3 7Ottawa Downtown graph for PM2.5 1.2Ottawa Downtown graph for NO2    
Parry Sound 18Parry Sound graph for O3 9Parry Sound graph for PM2.5 1.1Parry Sound graph for NO2    
Peterborough 28Peterborough graph for O3 5Peterborough graph for PM2.5 1.3Peterborough graph for NO2    
Port Stanley 47Port Stanley graph for O3 6Port Stanley graph for PM2.5 2.2Port Stanley graph for NO2    
Sarnia 42Sarnia graph for O3 6Sarnia graph for PM2.5 2.4Sarnia graph for NO2 0Sarnia graph for SO2  
Sault Ste. Marie 22Sault Ste. Marie graph for O3 6Sault Ste. Marie graph for PM2.5 1.2Sault Ste. Marie graph for NO2 0Sault Ste. Marie graph for SO2  
St. Catharines 35St. Catharines graph for O3 7St. Catharines graph for PM2.5 2.4St. Catharines graph for NO2    
Sudbury 28Sudbury graph for O3 8Sudbury graph for PM2.5 0.9Sudbury graph for NO2 0.1Sudbury graph for SO2  
Thunder Bay 27Thunder Bay graph for O3 19Thunder Bay graph for PM2.5 1.1Thunder Bay graph for NO2    
Tiverton 31Tiverton graph for O3 4Tiverton graph for PM2.5      
Toronto Downtown 17Toronto Downtown graph for O3 14Toronto Downtown graph for PM2.5 16.5Toronto Downtown graph for NO2    
Toronto East 17Toronto East graph for O3 8Toronto East graph for PM2.5 9.2Toronto East graph for NO2    
Toronto North 28Toronto North graph for O3 6Toronto North graph for PM2.5 4.5Toronto North graph for NO2 0Toronto North graph for SO2  
Toronto West 27Toronto West graph for O3 5Toronto West graph for PM2.5 10.9Toronto West graph for NO2 0Toronto West graph for SO2 0.23Toronto West graph for CO
Windsor Downtown 52Windsor Downtown graph for O3 N/AWindsor Downtown graph for PM2.5 3.8Windsor Downtown graph for NO2 0.1Windsor Downtown graph for SO2 0.22Windsor Downtown graph for CO
Windsor West 44Windsor West graph for O3 6Windsor West graph for PM2.5 7.7Windsor 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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