New Study Demonstrates Vast Majority of Commercial Fluoropolymers Meet Criteria for Polymers of Low Concern Designation

Conclusions Provide Further Evidence that PFAS Chemistries Should Not Be All Grouped Together for Purposes of Regulation

WASHINGTON, June 14, 2022 /PRNewswire/ -- The vast majority and types of fluoropolymers, which are part of the per- and polyfluoroalkyl substance (PFAS) family, meet internationally recognized criteria for being considered polymers of low concern (PLC), a designation for compounds that are expected to have insignificant environmental and human health impacts, according to a new scientific paper. The conclusions of the study, conducted by the American Chemistry Council's Performance Fluoropolymer Partnership (PFP), provide new evidence that PFAS regulations must clearly differentiate among the broad category of PFAS chemistries.

The paper, A Critical Review of the Application of Polymer of Low Concern Regulatory Criteria to Fluoropolymers II: Fluoroplastics and Fluoroelastomers, builds upon research conducted in 2018¹ that identified four fluoropolymers that met criteria for identifying polymers of low concern for potential adverse effects on human health or the environment. In this new paper, PFP researchers analyzed an additional 14 fluoropolymers and fluoroelastomers and determined they meet the PLC criteria, bringing the number to 18 fluoropolymers and representing approximately 96 percent of the global market for commercially available fluoropolymers.

Fluoropolymers and fluoroelastomers provide exceptional functionality and benefits across multiple critical end-use markets such as electronics, semiconductors, healthcare technology and devices, transportation, 5G telecommunications, and renewable energy. They are a key component driving the technologies used in cellphones, personal protective equipment, solar panels, medical devices, aircraft, and countless other products and industries.

"This paper provides conclusive evidence that an overwhelming percentage of the fluoropolymers in the products we rely on every day are of low concern for human health or the environment according to internationally recognized criteria," said Jay West, Executive Director of the PFP. "It also demonstrates even further that regulating the broad family of PFAS as one single category is neither scientifically sound nor appropriate."

There are 13 criteria used to determine PLC status: polymer composition, molecular weight, weight percentage of oligomers, electrical charge, reactive functional groups, functional group equivalent weight, low molecular weight leachables, water solubility, particle size, polymer stability, thermal stability, abiotic stability, and biotic stability.

While greatly increasing the number and scope of chemistries that meet the PLC criteria, the paper also demonstrates that in addition to fluoropolymers, several fluoroelastomers, ionomers, and amorphous fluoropolymers qualify as well. The result is that the most economically important fluoropolymers (by global market volume) pose minimal threats to humans or the environment.

The substances included in this study are: polyvinylidene fluoride (PVDF) homopolymer; PVDF copolymer; ethylene-chlorotrifluoroethylene (ECTFE) copolymer; ECTFE terpolymer; polychlorotrifluoroethylene (PCTFE); fluoroethylene-vinyl ether copolymer (FEVE); terpolymer of ethylene, tetrafluoroethylene, and hexafluoropropylene (EFEP); terpolymer of chlorotrifluoroethylene, tetrafluoroethene, and perfluoroalkyl-vinyl-ether (CPT); and terpolymer of tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride (THV), as well as specialty fluoroplastics amorphous fluoropolymers and fluorinated ionomers. The fluoroelastomers included in this study include tetrafluoroethylene-propylene co-polymer (FEPM);  hexafluoropropene-vinylidene fluoride co- and terpolymers (FKM); and a  tetrafluoroethylene-perfluoromethyl vinyl ether perfluoroelastomer (FFKM).

The authors also note that segmentation that clearly differentiates the broad PFAS family according to their properties, rather than the presence of a carbon-fluorine bond, is required for a scientifically sound, risk-based regulatory approach. "Regulating all PFAS as one homogenous group absent consideration of their properties, particularly when the properties are so demonstrably different, neglects basic scientific consideration of these properties, that are the foundation of substance differentiation," they write. "Therefore, we advocate for segmentation based on properties before performing any grouping-based risk assessment, placing stable, non-hazardous fluoropolymers, that meet the criteria to be considered polymers on low concern, in a separate category."

The study was published and announced on June 14, 2022, in the scientific journal Integrated Environmental Assessment and Management and can be accessed at https://doi.org/10.1002/ieam.4646 (open access pending) or by contacting Erich Shea at [email protected].  

¹ Henry, B. J., et al. A critical review of the application of polymer of low concern and regulatory criteria to fluoropolymers. Integrated Environmental Assessment and Management. Volume 14, number 3, pages 316-334. May 2018. Open Access. 

SOURCE American Chemistry Council