Toronto’s air quality ranked world’s worst as wildfire smoke settles in

Toronto has the worst air quality in the world as of Wednesday morning, with smoke from forest fires in northwestern Ontario settling in.

IQAir, a Swiss air quality technology company that operates the world’s largest real-time air quality information platform, ranked Canada’s largest city as the worst for air quality as of 9 a.m.

Toronto sat ahead of Kinshasa in the Democratic Republic of the Congo, Dubai, United Arab Emirates, Delhi, India, and Jerusalem, Israel.

Environment Canada said in an orange air quality warning that much of southern Ontario is impacted by the smoke, which may persist into Friday for some areas.

It advised Canadians to limit time outdoors and prioritize keeping cool inside.

“You may experience mild and common symptoms such as eye, nose and throat irritation, headaches or a mild cough. More serious but less common symptoms include wheezing, chest pains or severe cough. If you think you are having a medical emergency, seek immediate medical assistance,” Environment Canada said.

“People more likely to be impacted by wildfire smoke, including 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 air quality warning comes in addition to a heat warning that has persisted since Monday.

Maximum temperatures of 30 to 36 C are expected Wednesday, with humidex values making that feel like 38 to 42 C.

The heat is expected to continue into the evening and may carry into Thursday or Friday near Lake Erie and Lake Ontario.

Tuesday was the worst day during the heat wave as humidex values made it feel like 38 to 45 C in parts of southern Ontario.