Richard J Wenning, Wenning Environmental LLC, Portland, Maine, US
Published on JD Supra, 12 August 2025
ABSTRACT:
A clever title highlights one of many ongoing challenges facing the scientific and regulatory communities with per- and polyfluoroalkyl substances: how to define and classify PFAS. PFAS are a remarkably diverse group of more than 10,000 synthetic fluorinated compounds, unified by the presence of at least one carbon-fluorine (C–F) bond—a feature that imparts exceptional chemical stability and persistence in the environment, earning PFAS the designation as “forever chemicals.” A recent commentary by Sigmund et al. (2025), authored by 20 scientists, underscores the controversy surrounding the boundaries of the PFAS definition. They also highlight concerns about an International Union of Pure and Applied Chemistry (IUPAC) initiative that aims to resolve these definitional ambiguities and foster international consensus. This debate is not merely academic. The lack of a clear, universally accepted definition of PFAS complicates scientific communication, regulatory action, permitted critical uses, and the establishment of practical, science-based standards for contaminated land cleanup and nature restoration. As such, any effort to clarify what constitutes a PFAS is important to advancing public health protections, environmental stewardship, and the integrity of scientific research in this rapidly evolving field.
