Comment Submitted by Charlotte Lorthioir

Ref: USCG-2022-0471 Foam Fire-Extinguishing Systems Dear Administrator, My name is Charlotte Lorthioir and I am writing to you as a geologist and graduate of Boston College where I received a Master’s in geology, specializing in isotope geochemistry. I currently work in environmental remediation within the New York City metropolitan area, including the remediation of contaminated Brownfield and Resource Conservation and Recovery Act (RCRA) sites. I strongly advise the Coast Guard to avoid fire-fighting foams that contain per- and polyfluoroalkyl substances (PFAS) compounds, even if these compounds are not explicitly banned in the United States. PFAS are a class of chemical compounds with a characteristic C-F bond that prevents them breaking down naturally, making them “forever chemicals” that persist in ecosystems and water sources, accumulating over time in the human body. Over the last century industrial manufacturing in the U.S. has been playing a game of replacement chemistry, we manufacture a PFAS compound, use it extensively, then realize it’s hazardous to human health and pivot toward developing a new PFAS compound, until we discover that it’s also hazardous to human health. Please try to use non-PFAS foams, as the more we research these chemicals the more we discover how damaging they are to human health. Thank you, Charlotte Lorthioir