Pollutant concentrations for December 14, 2025, 10:00 am EST

Choose date options.

Pollutant concentrations for December 14, 2025, 10:00 am EST
Station O3 (ppb) PM2.5 (µg/m3) NO2 (ppb) SO2 (ppb) CO (ppm)
Barrie 22Barrie graph for O3 2Barrie graph for PM2.5 10.6Barrie graph for NO2    
Belleville 31Belleville graph for O3 3Belleville graph for PM2.5 2.4Belleville graph for NO2    
Brampton 31Brampton graph for O3 2Brampton graph for PM2.5 3.6Brampton graph for NO2    
Brantford 30Brantford graph for O3 3Brantford graph for PM2.5 2.1Brantford graph for NO2    
Burlington 31Burlington graph for O3 3Burlington graph for PM2.5 3.9Burlington graph for NO2    
Chatham 39Chatham graph for O3 2Chatham graph for PM2.5 4.5Chatham graph for NO2    
Cornwall 23Cornwall graph for O3 4Cornwall graph for PM2.5 4Cornwall graph for NO2    
Dorset 23Dorset graph for O3 2Dorset graph for PM2.5      
Grand Bend 33Grand Bend graph for O3 2Grand Bend graph for PM2.5 0.4Grand Bend graph for NO2    
Guelph 31Guelph graph for O3 2Guelph graph for PM2.5 3.1Guelph graph for NO2    
Hamilton Downtown 29Hamilton Downtown graph for O3 3Hamilton Downtown graph for PM2.5 4.7Hamilton Downtown graph for NO2 0.1Hamilton Downtown graph for SO2 0.15Hamilton Downtown graph for CO
Hamilton Mountain 32Hamilton Mountain graph for O3 3Hamilton Mountain graph for PM2.5 2.8Hamilton Mountain graph for NO2 0Hamilton Mountain graph for SO2  
Hamilton West 30Hamilton West graph for O3 3Hamilton West graph for PM2.5 3.8Hamilton West graph for NO2    
Kingston 27Kingston graph for O3 5Kingston graph for PM2.5 3.5Kingston graph for NO2    
Kitchener 29Kitchener graph for O3 2Kitchener graph for PM2.5 5Kitchener graph for NO2    
London 30London graph for O3 3London graph for PM2.5 4London graph for NO2    
Milton 29Milton graph for O3 7Milton graph for PM2.5 7.2Milton graph for NO2 0.3Milton graph for SO2  
Mississauga 30Mississauga graph for O3 3Mississauga graph for PM2.5 4.7Mississauga graph for NO2    
Newmarket 32Newmarket graph for O3 2Newmarket graph for PM2.5 3.2Newmarket graph for NO2    
North Bay 27North Bay graph for O3 1North Bay graph for PM2.5 0North Bay graph for NO2    
Oakville 30Oakville graph for O3 3Oakville graph for PM2.5 2.9Oakville graph for NO2    
Oshawa 28Oshawa graph for O3 2Oshawa graph for PM2.5 4.7Oshawa graph for NO2    
Ottawa Downtown N/AOttawa Downtown graph for O3 N/AOttawa Downtown graph for PM2.5 N/AOttawa Downtown graph for NO2    
Parry Sound 26Parry Sound graph for O3 2Parry Sound graph for PM2.5 1.7Parry Sound graph for NO2    
Peterborough 29Peterborough graph for O3 2Peterborough graph for PM2.5 1.8Peterborough graph for NO2    
Port Stanley 31Port Stanley graph for O3 3Port Stanley graph for PM2.5 2.6Port Stanley graph for NO2    
Sarnia N/ASarnia graph for O3 N/ASarnia graph for PM2.5 N/ASarnia graph for NO2 N/ASarnia graph for SO2  
Sault Ste. Marie 26Sault Ste. Marie graph for O3 2Sault Ste. Marie graph for PM2.5 6.4Sault Ste. Marie graph for NO2 0.1Sault Ste. Marie graph for SO2  
St. Catharines 31St. Catharines graph for O3 3St. Catharines graph for PM2.5 3.4St. Catharines graph for NO2    
Sudbury 26Sudbury graph for O3 1Sudbury graph for PM2.5 0Sudbury graph for NO2 0Sudbury graph for SO2  
Thunder Bay 29Thunder Bay graph for O3 2Thunder Bay graph for PM2.5 3.8Thunder Bay graph for NO2    
Tiverton 24Tiverton graph for O3 1Tiverton graph for PM2.5      
Toronto Downtown 21Toronto Downtown graph for O3 3Toronto Downtown graph for PM2.5 N/AToronto Downtown graph for NO2    
Toronto East 24Toronto East graph for O3 6Toronto East graph for PM2.5 11.5Toronto East graph for NO2    
Toronto North 24Toronto North graph for O3 3Toronto North graph for PM2.5 11Toronto North graph for NO2 0.4Toronto North graph for SO2  
Toronto West 23Toronto West graph for O3 5Toronto West graph for PM2.5 11.3Toronto West graph for NO2 0Toronto West graph for SO2 1.55Toronto West graph for CO
Windsor Downtown 28Windsor Downtown graph for O3 4Windsor Downtown graph for PM2.5 7.4Windsor Downtown graph for NO2 0.1Windsor Downtown graph for SO2 0.16Windsor Downtown graph for CO
Windsor West 28Windsor West graph for O3 4Windsor West graph for PM2.5 6.1Windsor 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.

Disclaimer