Midwest and Northeast Face Persistent Smoke From Canadian Wildfires

The National Weather Service has urged people in Midwestern and Northeastern states to keep an eye on local air-quality readings as smoke from hundreds of wildfires in Canada continues to drift across the border. Health officials recommend limiting outdoor activities where air-quality alerts are in effect and staying indoors with windows closed in areas receiving very unhealthy or hazardous warnings. Those with heart or lung conditions are advised to remain inside, and outdoor workers are urged to wear N95 respirators, which can filter at least 95% of fine particles.

Michigan lawmakers wrote to Canadian officials, stating, "Our constituents are breathing the consequences of this failure right now, and they deserve better than to be told, again, that it will be handled." The letter reflects growing political pressure as more than 150 fires burn unchecked in Canada.

Experts note that wildfire smoke contains water vapor, pollutants, particulate matter and gases such as carbon monoxide, which can aggravate asthma, increase the risk of heart attacks and strokes, and pose heightened danger to children, seniors, pregnant people and those with pre-existing health issues. When the Air Quality Index reaches unhealthy levels, masks such as N95 or P100 respirators are recommended for anyone who must be outdoors, though staying indoors remains the safest option.

Scientists link the increase in fire size and duration to hotter, drier conditions driven by climate change. NASA reports that human-caused warming has made severe wildfire conditions more frequent, extending fire seasons by more than a month in some regions compared with 35 years ago. The Joint Economic Committee estimates that wildfires cost the United States between $394 billion and $893 billion annually, accounting for health impacts, property loss and other factors.