Wildfire smoke linked to asthma spike in Canada, new study warns

A new Canadian study has found that wildfire smoke significantly increased asthma-related emergency room visits during the 2023 season. The study, published Monday in the Canadian Medical Association Journal, comes just as wildfire season kicks off in British Columbia — raising renewed concern about how poor air quality affects respiratory health.

Health experts are urging Canadians to stay alert, as wildfire smoke continues to be a major environmental health hazard across the country. Researchers analyzed health records across several provinces and observed a noticeable surge in ER visits due to asthma during the first wave of smoke in 2023.

Also read: Sturgeon County wildfire forces residents to prepare for evacuation

First wildfire smoke wave caused emergency room spike

During the initial smoke wave last year, emergency room visits for asthma jumped significantly, especially in communities closer to fire zones. Experts attribute the increase to the sudden and intense exposure to fine particulate matter (PM2.5), a key pollutant in wildfire smoke that can inflame the lungs and trigger asthma attacks.

Interestingly, when a second smoke wave hit several weeks later, asthma-related visits returned to normal levels. According to the authors of the study, this pattern suggests Canadians may have adapted their behavior — by wearing masks, staying indoors, and using air purifiers — once they understood the health risks of wildfire smoke exposure.

The contrast between the two waves underscores the importance of public health messaging and proactive response to air quality alerts.

Asthma and air quality: what Canadians need to know

Wildfire smoke doesn’t just affect people with asthma. It’s also known to worsen chronic respiratory diseases like COPD, bronchitis, and even cardiovascular conditions. The harmful particles in smoke can travel deep into the lungs and bloodstream, triggering inflammation, chest tightness, coughing, and wheezing.

Also read: Wildfires in Northeast B.C. trigger evacuations, infrastructure damaged

The Canadian Medical Association Journal study emphasizes that those with pre-existing conditions — particularly children, seniors, and people with asthma — are most at risk during wildfire season.

With the 2024 wildfire season already underway in British Columbia, public health officials are urging Canadians to take the following precautions when wildfire smoke is present:

Monitor local air quality indexes (AQI) via trusted government or weather apps

Stay indoors during poor air quality days, especially if you have asthma or breathing issues

Use HEPA air purifiers at home

Wear certified N95 masks when outside for extended periods

These preventative steps are proven to reduce exposure to wildfire smoke and minimize asthma symptoms.

Also read: Canada wildfires: Smoke spreads across America; heat waves, health risks, air quality alerts, July 4 holiday flight schedules, all you need to know

Wildfire smoke and respiratory health: a growing threat

As climate change continues to increase the frequency and severity of wildfires across Canada, so too does the risk to respiratory health. The study's authors warn that future smoke events may lead to even greater health burdens unless awareness, preparedness, and early intervention strategies improve.

With asthma-related ER visits directly linked to wildfire smoke exposure, experts say it’s essential for Canadians — especially those with underlying respiratory conditions — to stay informed and protected during smoke events.