Canada’s air pollution levels last year were worse than those in the United States for the first time since an air-quality firm started publishing its assessments in 2018. A report published Tuesday by Swiss firm IQAir says raging wildfires were a major influence on Canada’s drop in air quality in 2023.
While the report found Canada on average still has some of the least polluted air, public health experts have repeatedly warned about the health dangers of more intense wildfire seasons, fueled by human-caused climate change. “Air pollution is a silent killer,” said Dr. Samantha Green, a family physician with Unity Health Toronto and associate professor at the University of Toronto who was not involved with the report. “It’s a problem that I think we’re not used to thinking about, but that we need to be thinking about more.” Health Canada estimates air pollution contributes to 15,300 premature deaths every year in Canada. Wildfire smoke exposure is also strongly linked to chronic conditions, such as asthma, and increases in respiratory emergency room visits. The U.S. typically dominates the World Air Quality report’s list of 15 most polluted cities in both the U.S. and Canada, with Canadian cities appearing on the list just three times since the first assessment was published in 2018. But roles reversed last year as thick clouds of wildfire smoke descended over the country