TORONTO, July 15, 2026 – Smoke from wildfires in northern Ontario caused Toronto’s air quality to deteriorate sharply on July 15, with the city at one point ranked among the worst major cities in the world for air quality by an air quality monitoring platform. Reuters reported that Toronto’s Air Quality Health Index reached 10+, which is classified as “very high risk.” The combination of heat and smoke had a clear impact on travel and outdoor activities across the Greater Toronto Area.
That day, Toronto’s sky was covered by grey-yellow smoke, visibility declined, and the smell of smoke could be clearly noticed outdoors. In addition to downtown Toronto, Mississauga, York Region, Scarborough, North York and other parts of the GTA were also affected by smoke. Seniors, children, pregnant people, outdoor workers and residents with asthma, chronic lung disease or cardiovascular conditions faced particular health concerns.
Environment authorities in Canada generally advise residents to reduce or avoid strenuous outdoor activity when the Air Quality Health Index is in the high-risk or very-high-risk range. For commuters, construction workers, delivery workers and outdoor service workers who must go outside, wildfire smoke is not the same as ordinary haze. Fine particles can travel deep into the respiratory system and may trigger coughing, chest tightness, eye irritation or breathing discomfort.
Many newcomer families may be unfamiliar with the effects of wildfire smoke in Canada and may mistake yellow skies or smoky air for ordinary weather changes. In reality, wildfire smoke can drift into cities from hundreds of kilometres away. Even when there is no local fire, air quality can decline significantly within a short period. Families with seniors, children or people with chronic health conditions should try to keep windows and doors closed, reduce the amount of outdoor air entering the home and use air purifiers when appropriate.
Schools, summer camps and outdoor sports programs also need to adjust quickly based on air quality changes. Before sending children to outdoor activities, parents should check whether organizers have moved activities indoors, reduced physical intensity or postponed events. Seniors should also consider reducing or cancelling planned walks, gardening, outdoor square activities or social gatherings depending on their health condition.
The combination of heat and smoke increases the risk further. While keeping windows and doors closed to reduce smoke entering the home, residents should also monitor indoor temperatures to avoid heat-related illness. Those without air conditioning can go to indoor public spaces such as libraries, community centres or shopping malls for temporary relief.
Weather and air quality conditions may continue to change depending on wind direction and wildfire activity. Residents should keep checking updates from Environment Canada, local public health agencies and municipal authorities, rather than judging air safety only by sight. Anyone experiencing persistent breathing difficulty, chest pain, severe dizziness or other serious symptoms should seek medical help promptly.（LJI by Yuanyuan）
