Pollutant concentrations for October 17, 2026, 4:00 am EDT

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Pollutant concentrations for October 17, 2026, 4:00 am EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 21Barrie graph for O3 1Barrie graph for PM2.5 0.8Barrie graph for NO2    
Belleville 22Belleville graph for O3 0Belleville graph for PM2.5 1Belleville graph for NO2    
Brampton 23Brampton graph for O3 0Brampton graph for PM2.5 1.1Brampton graph for NO2    
Brantford 22Brantford graph for O3 14Brantford graph for PM2.5 1.7Brantford graph for NO2    
Burlington 22Burlington graph for O3 1Burlington graph for PM2.5 2.2Burlington graph for NO2    
Chatham 19Chatham graph for O3 1Chatham graph for PM2.5 0.3Chatham graph for NO2    
Cornwall 18Cornwall graph for O3 1Cornwall graph for PM2.5 1.1Cornwall graph for NO2    
Dorset 24Dorset graph for O3 0Dorset graph for PM2.5      
Grand Bend 27Grand Bend graph for O3 1Grand Bend graph for PM2.5 0.1Grand Bend graph for NO2    
Guelph 20Guelph graph for O3 1Guelph graph for PM2.5 1.2Guelph graph for NO2    
Hamilton Downtown 23Hamilton Downtown graph for O3 1Hamilton Downtown graph for PM2.5 1.1Hamilton Downtown graph for NO2 0.2Hamilton Downtown graph for SO2 0.12Hamilton Downtown graph for CO
Hamilton Mountain 25Hamilton Mountain graph for O3 1Hamilton Mountain graph for PM2.5 0.8Hamilton Mountain graph for NO2 0.1Hamilton Mountain graph for SO2  
Hamilton West 22Hamilton West graph for O3 1Hamilton West graph for PM2.5 1.3Hamilton West graph for NO2    
Kingston 21Kingston graph for O3 0Kingston graph for PM2.5 0.8Kingston graph for NO2    
Kitchener 20Kitchener graph for O3 1Kitchener graph for PM2.5 1.7Kitchener graph for NO2    
London 22London graph for O3 2London graph for PM2.5 2.9London graph for NO2    
Milton 23Milton graph for O3 0Milton graph for PM2.5 1.3Milton graph for NO2 0.1Milton graph for SO2  
Mississauga 22Mississauga graph for O3 1Mississauga graph for PM2.5 2.1Mississauga graph for NO2    
Newmarket 23Newmarket graph for O3 0Newmarket graph for PM2.5 0.4Newmarket graph for NO2    
North Bay 27North Bay graph for O3 2North Bay graph for PM2.5 1.2North Bay graph for NO2    
Oakville 22Oakville graph for O3 1Oakville graph for PM2.5 1.4Oakville graph for NO2    
Oshawa 23Oshawa graph for O3 1Oshawa graph for PM2.5 0.3Oshawa graph for NO2    
Ottawa Downtown 25Ottawa Downtown graph for O3 0Ottawa Downtown graph for PM2.5 1.3Ottawa Downtown graph for NO2    
Parry Sound 24Parry Sound graph for O3 0Parry Sound graph for PM2.5 0.3Parry Sound graph for NO2    
Peterborough 21Peterborough graph for O3 0Peterborough graph for PM2.5 0.5Peterborough graph for NO2    
Port Stanley 21Port Stanley graph for O3 1Port Stanley graph for PM2.5 1.6Port Stanley graph for NO2    
Sarnia 26Sarnia graph for O3 0Sarnia graph for PM2.5 0Sarnia graph for NO2 0.1Sarnia graph for SO2  
Sault Ste. Marie 19Sault Ste. Marie graph for O3 1Sault Ste. Marie graph for PM2.5 5.2Sault Ste. Marie graph for NO2 0Sault Ste. Marie graph for SO2  
St. Catharines 22St. Catharines graph for O3 0St. Catharines graph for PM2.5 0.8St. Catharines graph for NO2    
Sudbury 29Sudbury graph for O3 1Sudbury graph for PM2.5 0.8Sudbury graph for NO2 0Sudbury graph for SO2  
Thunder Bay 11Thunder Bay graph for O3 4Thunder Bay graph for PM2.5 5.3Thunder Bay graph for NO2    
Tiverton 24Tiverton graph for O3 0Tiverton graph for PM2.5      
Toronto Downtown 22Toronto Downtown graph for O3 1Toronto Downtown graph for PM2.5 3.5Toronto Downtown graph for NO2    
Toronto East 22Toronto East graph for O3 1Toronto East graph for PM2.5 1.9Toronto East graph for NO2    
Toronto North 22Toronto North graph for O3 1Toronto North graph for PM2.5 0.9Toronto North graph for NO2 0.1Toronto North graph for SO2  
Toronto West 20Toronto West graph for O3 1Toronto West graph for PM2.5 3.6Toronto West graph for NO2 0Toronto West graph for SO2 0.12Toronto West graph for CO
Windsor Downtown 19Windsor Downtown graph for O3 1Windsor Downtown graph for PM2.5 5.5Windsor Downtown graph for NO2 0Windsor Downtown graph for SO2 0.16Windsor Downtown graph for CO
Windsor West 21Windsor West graph for O3 1Windsor West graph for PM2.5 1.7Windsor 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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