Read Time: 4 Minutes
Takeaways:
- Studies show exposure to wildfire smoke can lead to increased lung and heart complications in cancer patients and survivors.
- Staying indoors when air quality is poor and improving indoor air quality can help reduce exposure to harmful wildfire smoke.
Impact: Huntsman Cancer Institute is driving research on wildfire smoke and cancer, delivering insights that are especially critical for protecting the health of communities across the Mountain West.
Wildfire smoke is becoming a growing public health concern, especially across the Western United States. For people with cancer or a history of cancer, understanding the risks, and how to reduce them, is especially important.
Judy Ou, PhD, MPH, an environmental epidemiologist at Huntsman Cancer Institute and assistant professor in the Department of Pediatrics at the University of Utah (the U), studies how environmental exposures like wildfire smoke affect cancer risk and outcomes.
“Wildfire smoke contains fine particles and toxic chemicals that can affect the lungs and heart,” she explains. “Even short-term exposure to wildfire smoke can be harmful for cancer patients and survivors.”
What Research Shows
Research from Huntsman Cancer Institute and other health organizations shows that wildfire smoke, a type of air pollution, can be especially harmful for cancer patients and survivors. By studying air pollution from traffic and industry, Ou found that air pollution is linked to increased lung and heart complications in people with cancer or a history of cancer. These complications range from urgent care visits to hospitalizations for respiratory infections and asthma, and cardiovascular conditions like stroke and heart attacks.
Wildfire smoke is considered more dangerous because it contains higher concentrations of toxic chemicals and additional chemicals that are not usually found in traffic or industrial air pollution.
“We think these effects may occur because chemicals in air pollution and wildfire smoke are highly inflammatory, which can trigger asthma, and can also speed up the formation of blood clots. Wildfire smoke can also spread infectious agents in the air, which increases the risk for respiratory infections,” says Ou.
Does Wildfire Smoke Cause Cancer?
Research also shows that people with repeated or long-term exposure to wildfire smoke may have an increased risk of cancer. While studies are still emerging, wildfire smoke has been linked to an increased risk for lung cancer. Lung cancer is the leading cause of cancer death in Utah despite its low smoking rate.
A prior study also found that people who live closer to wildfires have an increased risk of brain cancer. Multiple studies also suggest that wildfire smoke exposure after cancer diagnosis, after surgery, and while undergoing radiation treatments introduces negative health impacts among cancer patients, highlighting the importance of reducing wildfire smoke exposure during treatment.
Ou and her collaborators at Huntsman Cancer Institute have many ongoing studies to understand the health impacts of wildfire smoke on cancer patients and survivors, as well as ways to prevent and mitigate these health impacts.
“We have two projects that examine the impacts of wildfire smoke on lung cancer survival and treatment resistance, and I just completed a project that examined how the 2025 Los Angeles wildfires impacted cancer care and health complications among children with a cancer history,” Ou says. “We can learn many lessons from the experiences of other cancer centers and implement these lessons here in the Mountain West to ensure access to cancer care, to prevent illness, and to improve cancer outcomes even while wildfires are ongoing.”
Other projects led by Michelle Mendoza, PhD, researcher at Huntsman Cancer Institute and associate professor of oncological sciences at the U, examine the biological mechanisms by which wildfire smoke influences treatment response and worsens long-term outcomes in lung cancer patients.
“The mechanisms behind this phenomenon are unknown, and these scientific discoveries can lead to new treatments for lung cancer patients who are exposed to wildfire smoke,” Mendoza says.
Chen Chen, PhD, Huntsman Cancer Institute investigator and assistant professor of population health sciences at the U, also mentions the importance of the compounding effects of heat and wildfire smoke exposure. “In the public, we find that exposure to heat and wildfire smoke at the same time can lead to higher rates of respiratory and cardiovascular hospitalizations. This means that prevention and adaptation efforts need to simultaneously consider heat and wildfire smoke exposure.”
In addition, Ou and Anne Kirchhoff, PhD, MPH, Huntsman Cancer Institute investigator and professor of pediatrics at the U, have an ongoing study to explore the compounding impacts of air pollution, including wildfire smoke, and heat on cardiovascular and pulmonary complications in breast cancer patients and survivors. These steps are important for cancer patients and the broader population.
How to Protect Yourself
“There are several practical ways to reduce your exposure to wildfire smoke and protect your health,” Ou says.
Stay indoors when air quality is poor
- Keep windows and doors closed.
- Set your HVAC system to recirculate (turn off fresh air intake if possible).
Improve indoor air quality
- Use a high-efficiency HVAC filter (MERV 13 or higher if possible).
- Consider a portable HEPA air purifier that does not emit ozone.
- Replace HVAC and air filters after smoke events.
- Avoid using swamp coolers, as they bring in air from outdoors.
Limit outdoor exposure
- Avoid outdoor activity during smoky conditions.
- Wear a well-fitting N95 mask if you must go outside.
Avoid contact with smoke residue
- Do not touch or breathe ash.
- Wear gloves and a mask when cleaning up ash.
Air quality apps on your phone can be helpful during wildfire events. Ou recommends that cancer patients and survivors stay indoors during wildfire events even when the air quality index reports “Moderate” air quality.
“Cancer patients and survivors have special health needs that may not be reflected by standards created for the general public,” Ou warns. “In these situations, I encourage patients and survivors to exercise caution.”
In case evacuation becomes necessary, people with cancer should keep a 72-hour emergency kit, complete with medications, ready to go.
