Pollutant concentrations for
July 15, 2025, 4:00 pm EDT

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Pollutant concentrations for
July 15, 2025, 4:00 pm EDT July 15, 2025, 4:00 pm EDT

Station	O3 (ppb)	PM2.5 (µg/m3)	NO2 (ppb)	SO2 (ppb)	CO (ppm)
Barrie	29	24	4.1
Belleville	69	33	1.7
Brampton	61	25	2
Brantford	74	37	1
Burlington	71	32	5.5
Chatham	81	33	2.8
Cornwall	53	33	2.3
Dorset	42	21
Grand Bend	101	40	3
Guelph	65	31	1.6
Hamilton Downtown	65	32	2.2	0.4	0.31
Hamilton Mountain	64	32	3	0.1
Hamilton West	70	29	3.6
Kingston	61	25	2
Kitchener	63	33	2.2
London	72	35	2.2
Milton	68	33	3.4	0.3
Mississauga	71	27	3
Newmarket	59	27	2
North Bay	30	35	1.1
Oakville	65	31	2.3
Oshawa	75	30	2.9
Ottawa Downtown	42	30	1.7
Parry Sound	36	36	2
Peterborough	48	24	1.3
Port Stanley	68	32	3.2
Sarnia	76	36	11.5	11.5
Sault Ste. Marie	53	23	1.7	0.2
St. Catharines	68	31	1.5
Sudbury	34	29	1.2	0.2
Thunder Bay	18	32	2.2
Tiverton	70	33
Toronto Downtown	72	0	7.5
Toronto East	84	37	7.8
Toronto North	102	40	6	0.9
Toronto West	79	35	3.5	N/A	0.33
Windsor Downtown	93	45	3.3	0.6	0.35
Windsor West	92	49	3.8	0.8

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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