Parts of the Greater Toronto Area (GTA) are under an air quality warning on Monday alongside an ongoing heat warning in the region, Environment Canada says.

And even if you don’t feel any discomfort on your run, it doesn’t mean there’s no harm being done. The pollutants can have long-term effects such as reduced lung function, increased risk of respiratory infections and can be linked to countless other health issues.

Environment Canada urges residents to limit their time outdoors. But even when inside, most buildings can only reduce airborne pollutants by half.

Stations across Canada started measuring air quality every hour in 2024 because of the wildfires ... CBC's network investigative unit, CBC Toronto, CBC Manitoba and as a chase producer for Canada Tonight on CBC News Network. You can reach her at katie ...

Toronto and the GTA are under a heat wave and poor air quality warning issued by Environment Canada on July 14, 2025, due to wildfire smoke from northern Ontario. The poor air quality is expected to persist from Monday into Tuesday.