One of the current hot topics around firefighter cancer is exposure to PFAS. But what is PFAS, how are firefighters exposed, and how much do we know about their health effects? Here we’ll tackle several key questions related to this important health topic.
What is PFAS?
PFAS (per- and polyfluoroalkyl substances) have been used in a variety of industries, and are often present in food packaging, cleaning products and nonstick products. PFAS are a group of chemicals that include perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). Due to concerns about exposure and potential health effects, the Environmental Protection Agency (EPA) formed a PFOA Stewardship Program designed to eliminate the use of PFOA along with other long-chain PFAS in manufacturing in the United States.
What are the health effects of exposure to PFAS for firefighters?
In animal-based studies, exposure to PFAS has been linked to adverse reproductive, developmental and immunological effects, and may be related to development of cancer. The International Agency for Research on Cancer (IARC) has categorized PFOA as possibly carcinogenic to humans.
How are firefighters exposed to PFAS?
We believe that firefighters may be exposed to PFAS through exposure to the combustion of products containing the substances on the fireground (e.g., stain-resistant carpet and upholstery). Firefighters may have also been exposed to PFAS through firefighting foam. PFOS was used in the manufacturing of firefighting foam through the early-2000s, although some foam that contains it may still be in service. U.S.-based manufacturers have since used other short-chain PFAS in an effort to be safer.
Historically, PFAS also has been used in bunker gear, although in a form that has been considered a stable state. PFAS were used in stain/water-repellant fabrics within the layers of bunker gear to make gear water-resistant and reduce possibility of moisture-related skin burns and to protect firefighters from steam. While the long-chain version of the chemicals have been eliminated in the production process, it is possible that legacy gear manufactured before the regulations were put in place still contain the legacy chemicals, and that current gear has a newer version of the chemicals that are still being studied.
Whether the chemical is then entering the body of firefighters from absorption, inhalation or ingestion from their bunker gear and, if so, how is unclear. Additional research is currently underway to understand the depth and breadth of the concern.
Are PFAS entering the body of exposed firefighters?
Research on firefighters’ blood has found high levels of PFOA 24 hours after a fire, but questions remain as to how it got there. It is possible that accumulation of PFOS over time (such as from foam containing long-chain PFAS) may occur. It has also been suggested that the exposure may be due, in part, to the moisture barriers in gear. While it has been assumed that the PFAS in the moisture layer of gear are stable, recent research by Dr. Peaslee at Notre Dame has found that the chemicals may be present on the outside of the gear, but it is unclear how they got there or where they are coming from.
Dr. Peaslee’s initial work suggests that additional research is warranted. Research to understand exactly what risks PFAS poses to firefighters is in its infancy. It is unclear if/how the gear degrades, if/how the PFAS become less stable with time, and if/how PFAS is getting into the firefighters’ bodies. His work and the work of other scientists will shed light onto the risks moving forward.
The pursuit to better understand this issue is progressing. The IAFF has partnered with a number of research teams to study the issue in depth and have taken steps to collect information from stakeholders on all sides of the topic. Future research will examine whether results from initial work can be replicated to determine what risks exist and how PFAS are or are not entering the firefighters’ body. The peer-review process for publication of findings – the process where other scientists review the manuscripts before they are published – will also ensure that methods are appropriate and conclusions are sound.
What should a firefighter do while the scientific jury is still out?
In many ways, preventing the risks from PFAS exposure is similar to what is already being discussed related to cancer prevention. While there may be risks of PFAS exposure while wearing PPE, the risk of not wearing gear on the fireground is significant. With that in mind, follow these four steps to help limit exposure:
- Limit wearing firefighting turnout gear as much as possible. While gear is important for protection on the fireground, it is probably not as important when picking up groceries or out in the community.
- Keep gear as clean as possible. Dr. Dobraca and colleagues found that levels of PFOA were higher among firefighters who had not had their gear professionally cleaned in the previous year. Research by Dr. Kenny Fent and colleagues published in the Journal of Occupational and Environmental Hygiene found that cleaning gear after a fire with soap and water before leaving the scene reduced polycyclic aromatic hydrocarbon (PAH) contamination levels by 85%. While the research he did was not specific to PFAS, cleaning gear is generally a good idea for reducing many carcinogens.
- Keep gear out of living areas of the station to limit exposures.
- Keep gear out of places like the trunk of the car and the apparatus cab when possible. When it is necessary to carry gear in enclosed places, it is best to keep it contained.
What other factors impact firefighter health risks?
It should be noted that there is no evidence that any specific types of cancers are linked solely to PFAS exposure. A wide range of known and suspected carcinogens have been measured on the fireground and are known to enter firefighters’ bodies through dermal absorption and inhalation. Generally, limiting exposures as much as possible is important in addition to contamination control associated with gear.
Other occupational risk factors that are modifiable – diet, obesity, sleep disruption, tobacco use, and binge drinking – become even more important to control given the chemical exposures firefighters encounter, as all these factors can influence the development of cancer.
