Wildfire smoke pollution linked to more than 24K deaths a year, study finds

Huge 'firenado' forms over Utah wildfire

A large vortex or firenado formed over the Deer Creek Fire in San Juan County, Utah near the state's border with Colorado. (Credit: BLM/Jason Kirks via Storyful)

A new study reveals that chronic exposure to pollution from wildfires has been linked to tens of thousands of deaths annually in the United States.

The paper, published Wednesday in the journal Science Advances, found that from 2006 to 2020, long-term exposure to tiny particulates from wildfire smoke contributed to an average of 24,100 deaths a year.

Wildfire smoke linked to thousands of deaths per year

By the numbers:

The paper’s researchers focused on deaths linked to chronic exposure to fine particulate matter, or PM2.5, the main concern from wildfire smoke.

Using federal mortality data, the study’s authors analyzed the link between annual average exposure to PM2.5 from wildfire smoke and deaths by county in the lower 48 states. 

In this handout photo provided by the Texas A&M Forest Service, smoke billows over a road during the Smokehouse Creek fire on February 27, 2024 in the Texas panhandle (Credit: Texas A&M Forest Service via Getty Images)

Researchers also found that with every 0.1 microgram per cubic meter increase of PM2.5 across all these places, about 5,594 more people died each year.

How pronounced the link was between particulate exposure and death also varied by season and demographics. A stronger association appeared during cooler periods, and people in rural areas and younger communities appeared to be more vulnerable.

The study also did not account for other factors, such as whether a person smokes.

‘Wildfire smoke is very dangerous’

What they're saying:

The researchers said the study provided robust evidence for the chronic effect of wildfire smoke PM2.5 on mortality, underscoring the urgent need for targeted measures to mitigate the substantial and escalating burden of wildfires.

"Our message is: Wildfire smoke is very dangerous. It is an increasing threat to human health," Yaguang Wei, a study author and assistant professor in the department of environmental medicine at Icahn School of Medicine at Mount Sinai, told The Associated Press.

Other scientists who have studied the death toll from wildfire smoke were not surprised by the findings.

"The estimates they’re coming up with are reasonable," said Michael Jerrett, a professor of environmental health science at the University of California, Los Angeles who was not involved in the study. "We need more of them. It’s only if we’re doing multiple studies with many different designs that we gain scientific confidence of our outcomes."

Wildfire smoke may be worse for your brain than other air pollution

Big picture view:

Other research, published in 2024, suggested that wildfire smoke could have a more detrimental impact on brain health than other forms of air pollution. 

The findings were presented at the Alzheimer’s Association International Conference in Philadelphia.

RELATED: Study: Wildfire smoke may be worse for your brain than other air pollution

Researchers from the universities of Washington and Pennsylvania analyzed health records of 1.2 million older adults in Southern California from 2009 to 2019. They estimated residential exposure to PM2.5 from wildfire smoke and other sources over three years.

The study found that the odds of a new dementia diagnosis increased by about 21% for every 1 microgram increase in wildfire-related PM2.5 concentration. In comparison, the risk increased by only 3% for every 3 microgram increase in PM2.5 from non-wildfire sources.