March 10, 2025  | Charmaine Skoubo

Together, the increasing prevalence of wildfires in the United States and the widespread use of polyfluoroalkyl substances (PFAs) to fight them reveal a troubling intersection between environmental hazards and public health risks. PFAs, often called “forever chemicals” because of their persistence in the environment, are commonly found in firefighting foams, industrial products, and even household items.

While these chemicals play a role in combatting fires, their toxic legacy is contributing to long-term contamination of water, soil, and ecosystems. Coupled with the surge in wildfires fueled by the climate and human activity, the United States faces a dual crisis: escalating fire destruction and the pervasive health risks of PFAs exposure. Understanding this relationship is critical to addressing the environmental and health challenges of our time.

Wildfire Risks to Firefighters and the Public

Wildfires have increased dramatically over the last twenty years, with over ten million acres being burned in 2020 and almost nine million acres being burned in 2024. As firefighters battle these blazes, they face a risk of numerous health issues which exacerbate what is already a major problem for firefighters. Around 70 percent of line-of-duty deaths in the fire service were from cancer in 2016, according to federal data. In 2022, the World Health Organization’s International Agency for Research on Cancer went so far as to categorize firefighting itself as “carcinogenic to humans” due to the sheer volume of chemicals encountered on the job.

Firefighters also encounter carcinogens in the foam they use to suppress flames, and even in some of their protective gear. The International Association of Fire Fighters union says that using SCBA respirators is “the single most protective voluntary activity” a firefighter can take.

However, they aren’t typically available to wildland firefighters. Instead, many departments rely on neck gaiters or scarves to try and limit smoke inhalation. Even when SCBAs are available, their weight and short lifespan make them impractical for wildfire fighting, when firefighters are often battling blazes for 10 to 24 hours at a time.

“Wildland firefighters are exposed to many of the same respiratory hazards that structural firefighters avoid by using self-contained breathing apparatuses,” warned the U.S. Department of Homeland Security.

Wildland firefighters aren’t the only ones at risk. After recent events in Los Angeles, California, residents are slowly making their way back to their homes and are being warned to wear protective gear, not to drink the water or shower in it, and not to go into the ocean.

Once in the disaster zone, you’ll find residents wearing HAZMAT suits as they dig through debris, or at the very least, wearing N-95 masks and chemical-resistant gloves. Amidst a disaster, it may be hard to remember these small, but vital, health measures to take.

Air and Water Contamination After Wildfires

A 2024 study of the Marshall Fire in the Boulder, Colorado, area showed that bad air hung around inside homes even after the smoke had cleared. Researchers found elevated levels of metals and polycyclic aromatic hydrocarbons (PAHs) in ash, in addition to volatile organic compounds (VOCs) in air samples inside people’s homes. (Risks from ash and air pollution remain for people returning after wildfires. Here are symptoms to watch for | CNN) 

VOCs can be toxic to humans, and at least one VOC, benzene, is known to cause cancer. Exposure to PAHs is also associated with increased cancer incidence, according to the World Health Organization.

These chemicals aren’t only found in the air. After wildfire burns through a building, vegetation, and other infrastructure, the same hazardous materials and chemicals also deposit on the ground and enter the soil. Soil testing after a fire is highly recommended to check the levels of heavy metals and other toxins, as is coming up with a plan for soil remediation if necessary. 

As the soil becomes contaminated, so do water systems. High levels of benzene were found in the drinking water after large wildfire disasters in the 2017 Tubbs Fire in Santa Rosa, California and the 2018 Camp Fire in Paradise, California. Other volatile organic compounds are also known to contaminate tap water after fires. After the 2023 wildfires on Maui, the water was contaminated, but less so: It was "unsafe for drinking water, but it wasn't at a level that would cause health effects in the shower," says Purdue's Whelton. 

During wildfires, drinking water can get contaminated in two ways: via the water source and the system that delivers it. So far, it seems that the water in the reservoirs that serve the Los Angeles area may be largely spared, since much of LA's water comes from places far north and east of the county.

"There might be some 'atmospheric deposition' of ash on drinking water reservoirs, but this is generally not a serious concern" since it can be cleaned through water treatment, Randy Dahlgren, a professor of soil science at UC Davis, wrote in an email.

The biggest concern comes from the water delivery system and how water is distributed to local water treatment plants, water storage tanks, and through the pipes that bring water to homes and businesses. When parts of it are malfunctioning, burned or broken, the water system is vulnerable to contamination.

The infrastructure of the water system itself can melt and contaminate the water too, especially when the distribution channels are made from plastic. Webster points to examples from past fires in northern California: In the 2020 North Complex Fire, plastic liners in the water tanks melted. In the 2018 Camp Fire, plastic pipes and water meters melted. In all cases, melting plastic residue got pulled back into the water supply, causing contamination.

Escalating Fire Destruction and Wildland Management

Most of us can attest to the beauty of the forests around us, but with human activity (89% of forest fires are caused by humans), a warming climate, and a lack of forest management, these forests can quickly start disappearing while causing catastrophic damage in its path. For the general public, remember to take steps to reduce the risk associated in the aftermath of a wildfire. This includes how we can prevent them in the future.

Prescribed burns are a commonly known way to prevent wildfires and help the health of forests around us. However, in some states, controlled burns can be difficult to get started. Tahra Jirari, the director of economic analysis at the the Chamber of Progress, told Newsweek: "While the National Environmental Protection Act (NEPA) and other environmental laws were designed to protect the environment, they created a challenging timeline for forest management projects. Which is increasingly difficult because Mother Nature cannot wait for legal proceedings to play out. There have been several instances where project areas have burned while waiting to receive the correct permit or approval."

These approvals can take several years to get. The Clean Air Act also poses an obstacle, as the particulates that are released from controlled burns can violate it, despite their long-term benefits of preventing catastrophic wildfire events.

Other ways to help manage forests can include creating fire breaks, which are wide, open areas that can stop fire spread by the removal of the vegetation that fuels it. This is done with tractors or other heavy equipment. Also consider properly spacing planted trees, reducing vegetation which, if left unchecked, acts as fuel for a fire, and choosing root rot resistant trees, which are less susceptible to fire than diseased trees. Landowners living in a forested area can work to thin forested areas, which means removing weak and diseased trees to give healthy trees more space, and monitor the forest for pests and diseases while also diversifying tree species. Often, when wildfires come to healthy trees, the fire will slow down as well-managed forests retain more moisture and resist damage from insects and disease.

While some of us can’t do much in terms of forest management or fighting the fires ourselves, we can stay prepared for the aftermath of wildfires. 

Be aware that smoldering materials in the building may produce a variety of pollutants. Many adverse health conditions can be caused by inhaling or ingesting even small amounts of these pollutants. Use a respirator to limit your exposure, and wet debris to minimize breathing dust particles. When indoors, use an air purifier with a HEPA filter to clear the air from particles inside your home or building. 

Check for advisories from your local water utility. If you use a private well, have the water professionally tested for contaminants such as benzene, heavy metals, and VOCs. Carbon filters are effective at removing many VOCs and chemicals, including benzene. Boiling your water will not remove chemical contaminants after wildfires.

Conclusion

As the increasing prevalence of wildfires and the widespread use of PFAs in firefighting present serious environmental and health risks to both firefighters and the general public, being aware of the risks and mitigation tools available can make a big difference when it comes to health and safety.

For the general public and firefighters, it’s becoming increasingly important to get tested early and frequently for cancer. Early detection can help prevent cancer and other diseases from progressing further by treating it at an earlier stage. Firefighters, in particular, can stay prepared with proper gear, by knowing the risks and how to handle their gear, and by getting health tests early and often. For more information and resources on PFAs and Firefighting, visit the International Association of Fire Fighters website. 

Unfortunately, the toxic legacy of wildfires extends far beyond the immediate destruction, contaminating air, soil, and water, with long-term consequences that not only demand urgent action but careful attention, too.