Pollutant concentrations for
July 16, 2025, 5:00 am EDT

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Pollutant concentrations for
July 16, 2025, 5:00 am EDT July 16, 2025, 5:00 am EDT

Station	O3 (ppb)	PM2.5 (µg/m3)	NO2 (ppb)	SO2 (ppb)	CO (ppm)
Barrie	36	32	5.4
Belleville	28	31	5.2
Brampton	58	36	2.6
Brantford	13	37	2.8
Burlington	39	37	12.3
Chatham	65	26	2.8
Cornwall	42	32	0.8
Dorset	10	19
Grand Bend	41	34	2.5
Guelph	16	34	4.1
Hamilton Downtown	51	40	4.9	0.4	0.34
Hamilton Mountain	47	37	3.1	0.2
Hamilton West	27	37	15.2
Kingston	47	32	1.2
Kitchener	36	33	1.4
London	4	35	7.9
Milton	34	43	12.6	0.3
Mississauga	15	31	3.9
Newmarket	21	40	10.7
North Bay	18	23	8.5
Oakville	45	37	4.4
Oshawa	9	34	3
Ottawa Downtown	39	32	5.3
Parry Sound	20	24	0.6
Peterborough	32	32	3.7
Port Stanley	6	33	10.2
Sarnia	58	36	9.4	0.2
Sault Ste. Marie	31	19	1.5	0.2
St. Catharines	30	37	5.9
Sudbury	36	29	4.8	0.4
Thunder Bay	11	1	0.5
Tiverton	62	38
Toronto Downtown	40	10	12.3
Toronto East	25	39	10.5
Toronto North	12	39	10.4	0.5
Toronto West	7	44	43.5	N/A	0.45
Windsor Downtown	61	33	6.5	0	0.32
Windsor West	66	39	2.2	0

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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