Pollutant concentrations for
August 7, 2025, 11:00 pm EDT

Choose date options.

Pollutant concentrations for
August 7, 2025, 11:00 pm EDT August 7, 2025, 11:00 pm EDT
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 45Barrie graph for O3 33Barrie graph for PM2.5 4.3Barrie graph for NO2    
Belleville 49Belleville graph for O3 43Belleville graph for PM2.5 3Belleville graph for NO2    
Brampton 49Brampton graph for O3 27Brampton graph for PM2.5 4Brampton graph for NO2    
Brantford 32Brantford graph for O3 28Brantford graph for PM2.5 1.7Brantford graph for NO2    
Burlington 57Burlington graph for O3 28Burlington graph for PM2.5 1.2Burlington graph for NO2    
Chatham 46Chatham graph for O3 22Chatham graph for PM2.5 3.1Chatham graph for NO2    
Cornwall 38Cornwall graph for O3 27Cornwall graph for PM2.5 0.9Cornwall graph for NO2    
Dorset 42Dorset graph for O3 26Dorset graph for PM2.5      
Grand Bend 44Grand Bend graph for O3 16Grand Bend graph for PM2.5 1.9Grand Bend graph for NO2    
Guelph 51Guelph graph for O3 27Guelph graph for PM2.5 2.5Guelph graph for NO2    
Hamilton Downtown 42Hamilton Downtown graph for O3 32Hamilton Downtown graph for PM2.5 10.5Hamilton Downtown graph for NO2 10.5Hamilton Downtown graph for SO2 0.37Hamilton Downtown graph for CO
Hamilton Mountain 42Hamilton Mountain graph for O3 30Hamilton Mountain graph for PM2.5 5.4Hamilton Mountain graph for NO2 2.2Hamilton Mountain graph for SO2  
Hamilton West 50Hamilton West graph for O3 29Hamilton West graph for PM2.5 5.7Hamilton West graph for NO2    
Kingston 32Kingston graph for O3 45Kingston graph for PM2.5 12.4Kingston graph for NO2    
Kitchener 36Kitchener graph for O3 27Kitchener graph for PM2.5 5.3Kitchener graph for NO2    
London 32London graph for O3 20London graph for PM2.5 4.7London graph for NO2    
Milton 51Milton graph for O3 29Milton graph for PM2.5 2.4Milton graph for NO2 0.2Milton graph for SO2  
Mississauga 40Mississauga graph for O3 25Mississauga graph for PM2.5 3.6Mississauga graph for NO2    
Newmarket 48Newmarket graph for O3 29Newmarket graph for PM2.5 4.5Newmarket graph for NO2    
North Bay 38North Bay graph for O3 27North Bay graph for PM2.5 8.8North Bay graph for NO2    
Oakville 51Oakville graph for O3 29Oakville graph for PM2.5 3.6Oakville graph for NO2    
Oshawa 41Oshawa graph for O3 29Oshawa graph for PM2.5 3.2Oshawa graph for NO2    
Ottawa Downtown 40Ottawa Downtown graph for O3 40Ottawa Downtown graph for PM2.5 7.1Ottawa Downtown graph for NO2    
Parry Sound 53Parry Sound graph for O3 30Parry Sound graph for PM2.5 5.9Parry Sound graph for NO2    
Peterborough 39Peterborough graph for O3 27Peterborough graph for PM2.5 5.6Peterborough graph for NO2    
Port Stanley 45Port Stanley graph for O3 30Port Stanley graph for PM2.5 1.8Port Stanley graph for NO2    
Sarnia 46Sarnia graph for O3 20Sarnia graph for PM2.5 4.6Sarnia graph for NO2 0.3Sarnia graph for SO2  
Sault Ste. Marie 55Sault Ste. Marie graph for O3 21Sault Ste. Marie graph for PM2.5 1.9Sault Ste. Marie graph for NO2 0.1Sault Ste. Marie graph for SO2  
St. Catharines 36St. Catharines graph for O3 31St. Catharines graph for PM2.5 6.8St. Catharines graph for NO2    
Sudbury 50Sudbury graph for O3 22Sudbury graph for PM2.5 2.4Sudbury graph for NO2 0.3Sudbury graph for SO2  
Thunder Bay 20Thunder Bay graph for O3 7Thunder Bay graph for PM2.5 10.8Thunder Bay graph for NO2    
Tiverton 43Tiverton graph for O3 15Tiverton graph for PM2.5      
Toronto Downtown 47Toronto Downtown graph for O3 29Toronto Downtown graph for PM2.5 9.1Toronto Downtown graph for NO2    
Toronto East 47Toronto East graph for O3 28Toronto East graph for PM2.5 2.8Toronto East graph for NO2    
Toronto North 45Toronto North graph for O3 31Toronto North graph for PM2.5 4.7Toronto North graph for NO2 0.1Toronto North graph for SO2  
Toronto West 41Toronto West graph for O3 31Toronto West graph for PM2.5 6Toronto West graph for NO2 0Toronto West graph for SO2 0.3Toronto West graph for CO
Windsor Downtown 52Windsor Downtown graph for O3 16Windsor Downtown graph for PM2.5 3.7Windsor Downtown graph for NO2 0Windsor Downtown graph for SO2 0.23Windsor Downtown graph for CO
Windsor West 53Windsor West graph for O3 18Windsor West graph for PM2.5 3.8Windsor 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.

Disclaimer