September 2024: Dr. Heather Stapleton
Environmental Chemist and Exposure Scientist in the Nicholas School of the Environment at Duke University
Protecting North Carolina Firefighters: Investigating PFAS and Other Chemical Exposures Among Firefighters
“With this study, we hope to identify new mitigation strategies and make recommendations to protect firefighters while they are protecting us.”
Dr. Heather Stapleton

The most apparent danger that firefighters face while responding to a call is the fire itself, whether it be a burning building, or a raging wildfire. But there are other dangers firefighters face that aren’t as obvious to most people: the chemicals they are exposed to. Firefighters have a higher chance of developing cancers compared to the general population. Originally, it was thought this was due to the smoke and soot they inhale, but the chemicals they are exposed to while on duty could also play an important role in their health risks.
This is what Dr. Stapleton hopes to uncover in her North Carolina Firefighter Cancer Cohort Study. This study will recruit 1,000 active and volunteer firefighters across the state and test their blood for PFAS. She anticipates that these samples will help to identify the PFAS firefighters may be uniquely exposed to and how, and if, this is associated with cancer risks. This new study is part of a larger National Firefighter Cancer Cohort study, which is recruiting a total of 10,000 firefighters nationwide.
What do we currently know about firefighter’s chemical exposures?
PFAS are hazardous chemicals that almost everyone in our population has been exposed to through many pathways such as drinking water, consumer products, or food packaging. Unfortunately, firefighters are potentially exposed to PFAS through two additional pathways:
- Their turnout gear, which is treated with PFAS to make them water and oil resistant and to meet National Fire Protection Association Standards.
- AFFF (aqueous film forming foam), which is a material used to put out certain types of fire. Most AFFFs contain PFAS.
There are thousands of types of PFAS and many pathways to exposure. This study will be important to identify the types of PFAS firefighters are being exposed to specifically due to their profession. Exposures are also likely to vary by region and the type of fire you are responding to. Right now, we hope to start with answering the question of whether their turnout gear causes firefighters to have a higher PFAS concentrations in their blood compared to the general population. Right now, we just don’t know. With this study, we hope to answer these critical questions, and if needed, make recommendations to mitigate these exposures and protect firefighters while they are protecting us.
What distinguishes the NC Cohort Study from the National Cohort Study?
I think North Carolinians have a vested interest in understanding PFAS exposure because of our state’s unfortunate experience with high levels of these chemicals in our drinking water. We have already spoken with firefighters who are interested in getting their blood tested and understanding their health risks. Support for this statewide study gives these firefighters a point of entry into the national study and an opportunity to get tested where they previously may not have had access to the national study.
A unique aspect of the North Carolina study itself is the use of silicone wristbands to track chemical exposures. These bands act as surrogates for human skin and can absorb the chemicals in the air around us that the person is exposed to. They are also water resistant, so participants can consistently wear them without washing away the chemicals the wristband previously absorbed. Participants will be asked to wear them during specific parts of their day to discern where and when firefighters are being exposed to certain chemicals. While there is a focus of PFAS in both studies, these bands will allow us to explore other chemicals firefighters are exposed to that aren’t included in the national study.
For example, a pilot study conducted in partnership with Durham County firefighters in 2019 found high levels of exposure to brominated flame retardants while on duty compared to off duty. This exposure wasn’t associated with responding to a fire, so this poses the question of where other sources of chemical exposures arise. Is it something in the fire station? Are there harmful compounds in the fire trucks? We just don’t know, but we hope this study and use of the wristbands can help provide insight and answer these important questions, revealing what chemicals firefighters are exposed to and where these exposures are occurring.
The silicone bands aren’t currently being used broadly in national study, but we are advocating for their use. Due to limitations with time and resources, it’s just not feasible currently. Right now, we are focusing on supporting North Carolina firefighters with a hope to scale up in the future.
What is your message to firefighters concerned about their exposure to these chemicals?
Help us to help you by enrolling in the study! The only way we can advance our knowledge around PFAS, chemical exposures, and cancer risks among firefighters is to engage and partner with firefighters. We want this study to be a true partnership with North Carolina firefighters, and we plan to continue to support them however we can by answering questions they have about their exposures. Only by working together can we collect the necessary data, assess the risks, understand where these exposures are coming from, and inform policies that will mitigate exposures.