Protective clothing worn by wildland firefighters and which is available commercially, often contains harmful amounts of PFAS or synthetic chemicals classed as per- and polyfluoroalkyl substances in textiles, says a new study by the National Institute of Standards and Technology (NIST).
- This latest study by Andre L Thompson et al on ‘Per- and Polyfluoroalkyl Substances in Textiles Present in Firefighter Gloves, Hoods, and Wildland Gear’ analysed gloves and hoods worn by structural firefighters (those who fight fires in buildings), as well as gear worn by wildland firefighters. The researchers were particularly interested in hoods and gloves because they come in direct contact with skin, as opposed to coats and pants that are worn over a base layer.
- Experiments in earlier research had looked at the level of PFAS in firefighter coats and pants and how wear and tear can increase the amount of measurable PFAS in these garments.
- Wildland gear includes the protective shirt and pants worn for fighting wildfires. It’s designed for long treks over difficult terrain, so it trades off some heat protection for mobility. Unlike the thick, heavy coat and pants used to fight a structural fire, wildland gear is like something you might wear camping with extra heat protection.
- NIST conducted these studies at the behest of Congress, which called on NIST to study PFAS in firefighter gear in the 2021 National Defense Authorization Act.
THE RESEARCH: The NIST team led by chemist and study co-author Rick Davis, tested four types of gloves, eight types of hoods, and nine types of wildland firefighter gear from several manufacturers of firefighter gear in 2021–23.
- The researchers pulled the garments apart into 32 textile samples and extracted PFAS from the samples into a solvent. Then they tested each solvent to see if it contained any of 55 different PFAS chemicals.
- After running these tests, the team found measurable amounts of PFAS in 25 of the 32 textile samples.
- The hoods contained low PFAS levels. In almost all cases, the amount of PFAS in hood layers was too small to be measured confidently.
- The inside layers of the gloves had amounts of PFAS similar to those found in the inside layers of coats and pants tested in prior studies.
- Wildland gear is made of only one layer. The assumption among researchers was that this layer was unlikely to contain much PFAS. In general that was true, as most of the wildland gear tested had low levels of PFAS. But there were some cases that had notably high levels.
- Across all the textiles tested in this study, the largest total concentration of PFAS in a single sample was about 4,240 micrograms per kilogram from a piece of wildland gear.
- The researchers plan to run a follow-up study on the same samples to see how wear and tear might increase the amount of detectable PFAS in hoods, gloves and wildland firefighter gear.
