Air quality tanks as wildfire smoke spreads across huge swaths of Canada

During such conditions, everyone’s health is at risk regardless of their age or health status, Environment Canada said in its alert on Wednesday.

Canadians across many parts of the country woke up to smoky skies as Environment Canada issued air quality alerts for several major cities on Wednesday. Smoke from wildfires in northwestern Ontario is causing very poor air quality and reduced visibility, with hazy conditions expected to persist until Friday morning, Environment Canada said in an alert on Wednesday. A similar alert was issued for parts of northern Manitoba, where poor air quality is expected to last until Thursday.

A yellow alert was also issued for Vancouver, with residents of British Columbia being asked to watch out for wildfire smoke over the next 24 to 48 hours. Toronto had the worst air quality among major cities in the world on Wednesday, with Environment Canada saying the city scored eight on the Air Quality Health Index. The AQHI is a scale ranging from one to 10 and shows the risk that air quality in your area may pose to your health.

An AQHI score of one to three is considered “low risk,” four to six is considered “moderate risk” and seven to 10 is considered “high risk.” Yellowknife joined Toronto as the other Canadian city at high risk on Wednesday, with an AQHI of seven. During such conditions, everyone’s health is at risk regardless of their age or health status, Environment Canada says.

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People aged 65 and older, pregnant people, infants and young children, people with an existing illness or chronic health condition, and people who work outdoors should avoid strenuous activities outdoors and seek medical attention if experiencing symptoms, the agency said. “When indoors, keep windows and doors closed as much as possible. When there is an extreme heat event occurring with poor air quality, prioritize keeping cool,” Environment Canada said in its alert.

For those who need to spend time outdoors, using a well-fitting face mask, such as an N95 mask, can help reduce exposure to fine particles in the smoke.