New UBC study reveals health dangers when extreme heat and smoke collide – CTV
June 23, 2025
As wildfires burn across the country and temperatures continue to climb, many Canadians are likely to face a mix of smoky skies and intense heat this summer.
New research from the University of British Columbia suggests that combination may pose a particularly serious threat to human health.
The study—led by Dr. Sarah Henderson, professor at UBC’s School of Population and Public Health and scientific director at the B.C. Centre for Disease Control—looked at how simultaneous exposure to wildfire smoke and high temperatures can impact illness and death rates.
Henderson and her team looked at more than 21,000 deaths that occurred outside hospitals and care facilities in the greater Vancouver area over 13 wildfire seasons, from 2010 to 2022.
“There was a higher risk on those days that were both hot and smoky,” said Henderson.
However, she says the relationship between heat and smoke isn’t straightforward. While smoke-related health risks climb quickly at moderate exposure and then tend to level off, she says the dangers linked to extreme heat keep rising sharply.
