Toronto

https://www.thestar.com/news/gta/2023/06/28/torontos-air-quality-is-among-the-worst-in-the-world-again-due-to-wildfire-smoke.html

We’re number one.

Toronto claimed top spot on a list of the world’s worst air quality on Wednesday, according to global air quality tracker IQAir, as smoke from forest fires over northeastern Ontario and Quebec moved into the city.