The Health Risks of Wildfire Smoke


Public health officials and state experts are increasingly concerned about residents’ chronic exposure to toxin-filled smoke.

This year has seen the highest number of wildfires in a decade, with more than 59,000 blazes burning nearly 7 million acres nationwide, according to the National Interagency Fire Center. Although the total area burned was lower than in some recent years, thick smoke still blanketed communities across the country.

Climate change is causing more frequent and severe wildfires, harming the health of Americans, said Lisa Patel, deputy executive director of the Medical Society Consortium on Climate and Health, which raises awareness of the health effects of climate change.

“The data we have is very frightening,” she said. “We are currently living a natural experiment – we have never had fires so frequently.”

As researchers focus on public health effects, public health and environment officials across the country have had to issue more air quality advisories and provide guidance and shelter to struggling residents during periods of heavy forest fire smoke.

And while wildfires generally create more immediate and visible disruptions to the lives of people in the West, researchers worry that the fine particles may actually affect the breathing of more people in the states. most populated east.

Patel sees the effects of wildfires in her work as a pediatrician at Stanford Medicine Children’s Health, treating more women and underweight and premature infants in the neonatal intensive care unit when wildfires rage in northern California.

Studies show that chronic exposure to smoke from wildfires can cause asthma and pneumonia, and increase the risk of lung cancer, stroke, heart failure and sudden death. The very old and the very young are the most vulnerable. According to a 2021 study in the journal Pediatrics, particles in wildfire smoke are 10 times more harmful to children’s respiratory health than other air pollutants.

Why Seattle currently has the worst air quality in the world

What worries experts are particles in the air with a diameter of less than 2.5 microns; there are about 25,000 microns in an inch. People inhale these microscopic pieces, which can then travel deep into their lungs, irritating mucous membranes and inflaming tissues. The particles are small enough to enter the bloodstream, which can lead to other short- and long-term health effects.

Particles in smoke from wildfires are even hampering national progress in reducing air pollution, after decades of improvement.

The Clean Air Act has significantly reduced the level of toxic particles from industrial and automobile pollution across the country since 1970, according to the Environmental Protection Agency. But air pollution is expected to worsen in parts of the West from wildfires, some researchers have found. A United Nations report this year warned of a “global wildfire crisis”, saying the likelihood of catastrophic wildfires could increase by up to 57% by the end of the century.

Researchers are trying to better understand how more frequent wildfires affect human biology.

“That sinking feeling”

Keith Bein, a professional research associate at the University of California, Davis, in 2017 established a rapid response mobile research unit that he deploys to fires across the state. He’s like a storm chaser but for forest fires.

With his mobile unit, Bein can measure particles in the air, bring samples back to his lab, and then determine their toxicology and chemical compositions. Near these fires, he said, the smoke is so bad it seems unavoidable.

“The smoke comes in and you get that sinking feeling again,” he said.

Massive wildfires tearing communities apart are becoming more common. The fires are not only burning trees, but also synthetic materials in homes. And with repeated exposure to different particles, the health risks are more pronounced and can progress to chronic conditions, Bein said.

Researchers are just beginning to understand how more frequent wildfires in residential areas affect human health, he said.

“It happens more frequently every summer,” he said. “The duration of the fires is getting longer. Public exposure to smoke is also increasing. Unique events take place every summer. It’s a different type of exposure.

In 2020, an Environment International study found that winter flu seasons in Montana were four to five times worse after bad wildfire seasons, which typically last from July to September. The findings shocked the study’s lead author, Erin Landguth, an associate professor at the University of Montana.

Smoke from wildfires harms more people in the eastern US than in the west, study finds

“We know that hospitalizations for asthma and other respiratory issues increase within days or weeks after wildfires,” she said. “The thought that it could potentially have effects later on and how it can affect our immune system is really scary.”

Landguth extends his study to all Western states. She expects to find a similar trend in the mountain west and the Pacific Northwest. The monsoon season in Arizona and New Mexico could disrupt the trend there, she said, while air pollution is already so bad in California from smog and other pollutants. that it may be difficult to determine how wildfires affect human health.

But wildfires aren’t just in the West, and their health impact isn’t geographically isolated. Some fires burn so intensely at such high temperatures that smoke rises into the atmosphere, where strong winds can carry smoke long distances.

This was evident in 2021 when the sun shone red and skies turned hazy over New York and across the Northeast as smoke drifted from massive wildfires in California, Oregon and other parts of the world. other western states.

Smoke also harms the health of more people in the eastern United States than in the west, said Katelyn O’Dell, a postdoctoral researcher at George Washington University, who published the finding in a study by GeoHealth. in 2021.

Smoke from wildfires contributed to more asthma-related deaths and hospital visits in eastern communities than those in the west, she and other researchers found, in part to due to higher population density.

The smoke hitting the eastern states is not just coming from the west; there are wildfires and prescribed burns across the United States, O’Dell said.

“It’s sometimes easy to feel distant from the fires and their impacts when you’re away from the flames of these big western wildfires that are making the news,” she said. “But wildfires are impacting the health of the United States”

The next orange sunset people enjoy should be a time to check out an air quality mobile app, she said.

In Minnesota, the state has issued 46 air quality alerts since 2015, according to the state Pollution Control Agency. Of these, 34 were due to smoke from wildfires, and 26 of them were emitted last year.

It took state officials by surprise, said Kathy Norlien, a researcher with the Minnesota Department of Health. The wildfire smoke hazard comes not just from plumes drifting off the west coast and into Canada, but also from wildfires in boundary waters — a lake-filled region in the upstate. Norlien said she expects the problem to get worse in the coming years.

“At this point, we are anticipating the worst-case scenario,” she said. “We haven’t had the scale that Western states have had. But with climate change and concerns over drought and dry conditions, planning is of the utmost importance.

Norlien regularly meets with members of the Minnesota Pollution Control Agency and other state officials about how to get the message out to state residents about the growing wildfire risk to the public health, encouraging residents to sign up for air quality alerts. State officials also established larger community centers and buildings as safe air shelters.

The public plays a huge role in both preventing (nearly 90% of wildfires are human-caused, according to US government data) and adapting to wildfires, many experts have said. .

For people living in fire-prone areas, there are non-flammable building materials for new homes and indoor air cleaners and improved HVAC systems. But those solutions may be too expensive for some families, Patel said.

She advises families on how to stay safe affordably during the wildfire season, encouraging the use of N95 and KN95 masks, which have played a vital role in combating the spread of the coronavirus. She also shares do-it-yourself air filtration system designs.

But she stressed that wildfires will continue to rage across the country and will have adverse health effects unless climate change is brought under control through serious public policy. Until then, climate change will continue to be the biggest threat to public health, she said.

“Before, summer was a time I looked forward to,” she said, “but now I look at it in dread with the heat and the forest fires.”

This article was produced by Stateline, an initiative of the Pew Charitable Trusts.

Comments are closed.