Satellites capture wildfire smoke as Toronto records the worst air quality in the world, Canada

Toronto recorded the worst air quality in the world on Friday, June 6, 2025, as wildfire smoke blanketed the city, prompting health warnings and disrupting daily life.

Toronto briefly recorded the worst air quality in the world on Friday, June 6, as wildfire smoke spread across Ontario. The city’s air quality health index (AQHI) reached 9, which is high risk, on Friday afternoon.

Earlier in the afternoon, Toronto’s air quality was ranked second worst in the world, according to data from Swiss air quality tracker IQAir. At around 16:15 local time (LT), the city’s AQHI reached 10 — marking the worst air quality worldwide.

The wildfire smoke prompted Environment Canada to issue a special air quality statement for the Greater Toronto Area (GTA), much of southern Ontario, as well as five other provinces.

Environment Canada urged residents in areas where the air quality statement was in effect to limit their time spent outdoors.

Environment Canada’s David Phillips said that air quality is deteriorating as wildfires ramp up across the country. Since the beginning of the month, 15 new out-of-control wildfires have been burning in northern Ontario and Western Canada.

Friday’s heavy smoke prompted not just health concerns but also disrupted daily routines, as visibility dropped across Toronto. The Lung Health Foundation also issued statements cautioning the public about the harmful effects of prolonged exposure to smoke particles, especially for those already living with asthma or other lung conditions.

As of Friday, the air quality is expected to improve to moderate levels through the weekend, although it may fluctuate.

Feature image credit: Manitoba Government