SmogRank / World / Canada / Quebec / September 2023

Most polluted cities in Quebec, Canada, September 2023

14 cities in Quebec, Canada ranked by their average PM2.5 over the 30 days. Worst: Sherbrooke at 11.1 µg/m³, #393 of 2,128 cities in the world. Cleanest: Rouyn-Noranda at 8.0. A city needs measurements on 70% of the days to be ranked.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

← Sherbrooke 0% 0.75%0

Every city in Quebec, Canada ranked for September 2023, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.

1Sherbrooke
0%
2Saguenay
0%
3L'Ancienne-Lorette
0%
4Brossard
0%
5Granby
0%
5Québec
0%
7Montréal
0%
8Drummondville
0%
9Rivière-des-Prairies–Pointe-aux-Trembles
0%
10Bécancour
0%
11Dorval
0%
12Saint-Jean-sur-Richelieu
0%
12Shawinigan
0%
14Rouyn-Noranda
0%

Good0–50

Moderate51–100

Sensitive groups101–150

Unhealthy151–200

Very unhealthy201–300

Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

All cities in the world, September 2023 · All cities in Canada, September 2023 · Quebec now

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SmogRank, most polluted cities in Quebec, Canada, PM2.5, September 2023, smogrank.com/ca/region/quebec/history/2023-09 (accessed 6 Oct 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.