Reported by World Air Quality Index today.
It is the strongest of the 9 detections recorded within 20 km of this point since 21 May 2026. The last comparable one was on 26 August 2026.
What the source measured
World Air Quality Index reported: AQI 1757 (Hazardous) at Anjou, Montreal, Canada
The air quality index read 1,757 (Hazardous) at the Anjou, Montreal, Canada station.
An estimated 41,277 people live within 5 km of this point.
How we know
One source: World Air Quality Index. Not yet confirmed by a second, independent source.
Our own score for this event is 55 out of 100, at 66 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Computed under scoring rules v4. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Air Quality |
| Severity | Critical |
| Calamity Score (ours) | 55 / 100 |
| Our confidence | 66% |
| Coordinates | 45.6028, -73.5589 |
| Nearest City | Saint-Léonard (4 km) |
| Population Exposed | 41.3K within 5 km |
| Impact Tier | significant |
| Timestamp | 2026-09-02T17:00:00.000Z |
| Source | https://aqicn.org/city/@8625 |
Score Breakdown
Technical Details
| Aqi | 1757 |
| AqiCategory | Hazardous |
| StationName | Anjou, Montreal, Canada |
| StationUid | 8625 |
Safety Information
When air quality is hazardous: stay indoors with windows closed, and run a filtered air purifier if you have one. Avoid outdoor exercise. Children, older adults and anyone with heart or lung conditions are affected first and worst — an N95 respirator helps outdoors, a cloth mask does not.
Series begins 8 March 2026. Comparisons refer to that period only. Collection gap: 14-26 August 2026.
This data is aggregated algorithmically from scientific sources. Not a replacement for official emergency warnings.
Want to know when something happens near Saint-Léonard?
Calamity.live data shows a air quality event with CalamityScore 55/100, near Saint-Léonard (Canada), based on data from waqi. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.