A critical review of the application of polymer of low concern regulatory criteria to fluoropolymers II: Fluoroplastics and fluoroelastomers

Abstract

Fluoropolymers are a distinct class of per‐ and polyfluoroalkyl substances (PFAS), high molecular weight (MW) polymers with fluorine attached to their carbon‐only backbone. Fluoropolymers possess a unique combination of properties and unmatched functional performance critical to the products and manufacturing processes they enable and are irreplaceable in many uses. Fluoropolymers have documented safety profiles; are thermally, biologically, and chemically stable, negligibly soluble in water, nonmobile, nonbioavailable, nonbioaccumulative, and nontoxic. Although fluoropolymers fit the PFAS structural definition, they have very different physical, chemical, environmental, and toxicological properties when compared with other PFAS. This study describes the composition, uses, performance properties, and functionalities of 14 fluoropolymers, including fluoroplastics and fluoroelastomers, and presents data to demonstrate that they satisfy the widely accepted polymer hazard assessment criteria to be considered polymers of low concern (PLC). The PLC criteria include physicochemical properties, such as molecular weight, which determine bioavailability and warn of potential hazard. Fluoropolymers are insoluble (e.g., water, octanol) solids too large to migrate into the cell membrane making them nonbioavailable, and therefore, of low concern from a human and environmental health standpoint. Further, the study results demonstrate that fluoropolymers are a distinct and different group of PFAS and should not be grouped with other PFAS for hazard assessment or regulatory purposes. When combined with an earlier publication by Henry et al., this study demonstrates that commercial fluoropolymers are available from the seven participating companies that meet the criteria to be considered PLC, which represent approximately 96% of the global commercial fluoropolymer market. Integr Environ Assess Manag 2023;19:326–354. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

PFAS: forever chemicals—persistent, bioaccumulative and mobile. Reviewing the status and the need for their phase out and remediation of contaminated sites

“…In their production PFOA and its substitutes such as ADONA and HFPO-DA often serve as emulsifiers. Fluorine-free processing aids have rarely been used [20]. • Perfluoropolyethers (PFPE) exist as liquids or greases and are used in electronic industry as lubricants [21].…”

“…The manufacturers consider fluoropolymers as 'polymers of low concern' (PLC) because they were inert, non-bioavailable, and non-toxic [20,351] and met all the criteria to be considered harmless polymers not requiring regulation. In addition, they argue that these polymers were not substitutable in many applications due to their special properties [20]. In contrast, Lohmann et al include manufacturing and waste disposal in their assessment [8].…”

Copolymers of vinylidene fluoride with functional comonomers and applications therefrom: Recent developments, challenges and future trends

“…However, drawbacks arise from the cost and environmental issues of ,-diiodoperfluoroalkanes, regarded as PFASs and probably not in the family of polymers of low concern (PLC) because of their low molar masses. [370] Nevertheless, ITP can be adapted to hydrocarbon monomers [(meth)acrylate and styrenic] and, particularly, to fluoroalkenes, for which ITP is a mature technology industrially scaled up.…”

“…Fluoropolymers are thermally, biologically and chemically stable, non-mobile, nonbioaccumulative, non-toxic and display well-established safety profiles. They fullfill the widely accepted polymer hazard assessment criteria to be considered PLC [96][97][370][371][372]. Commercially Actually, these copolymers are essential to achieving important societal goals such as renewable energies, decarbonization, and/or competitiveness in the digital transition [371].…”

Recycling and the end of life assessment of fluoropolymers: recent developments, challenges and future trends

“…More recently, the American Chemical Council prompted the Fluoropolymer Industry Group (Fluoropolymergroup) to investigate a similar study on 14 additional fluorinated (co)polymers. 182 FPs and the Stockholm Convention persistent organic pollutant (POP) criteria meet the persistence criterion only, not the bioaccumulative, toxic, and mobile criteria. Actually, their physico-chemical properties prevent their bioavailability, bioaccumulation, toxicity, and degradation.…”