Among the major synthetic chemicals, Per- and polyfluoroalkyl substances (PFAS) are extensively used to produce many consumer products. However, these chemicals are non-degradable, making them a hazard for humans and the environment. The recent shift toward sustainable and eco-friendly industrial practices has motivated experts and researchers to look for efficient techniques to promote defluorination of PFAs. This article will highlight recent breakthroughs in the defluorination of PFAs.
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A Brief Introduction to PFAs
The origin of PFAs for use in various industries and products dates back to the 1940s. PFAs are highly resistant to grease, oil, high temperatures, and water, making them a viable substance for several applications, including carpets, furniture, adhesives, cleaning supplies, cosmetic products, the aerospace industry, automotive parts, the development of fire-fighting foams, and the electronics industry.1
PFAs are among the most persistent human-synthesized chemicals, also famously referred to as the “forever” chemicals. This is due to the presence of the Carbon-Fluorine bond in these chemicals, which is among the strongest chemical bonds, allowing these substances to stay in the environment unharmed. However, these chemicals leak into the environment and water bodies. PFA-contaminated water and food products cause damage to living organisms.
Dangers Associated with PFAs
According to the National Health and Nutrition Examination Survey (NHANES), about 97 % of the US population has been exposed to PFA-contaminated food and water, which has led to the detection of PFAs in their blood work.
The US National Institute of Environmental Health Sciences has supported several research studies on the effects of PFAs on humans. These studies have revealed that PFAs may delay the onset of puberty, especially in females.
PFAs have also been found to affect liver functioning in humans and reduce bone mineral density over time. These factors increase the risk for liver cancer and other chronic diseases like osteoporosis.2 This is the core reason government organizations all over the world are supporting research studies to ensure degradation of PFAs by defluorination and a reduction in their concentration.
Room Temperature Defluorination of PFAs Using Sodium Dispersion Methods
Traditional methods for defluorinating substances like PFAS and Polytetrafluoroethylene (PTFE) are highly challenging. They require high temperatures, complex reagents, and specific reaction conditions, which severely affect the cost-effectiveness of the defluorination process.
Experts have devised a novel defluorination process for PFAs using the sodium dispersion method. The research team used commercially available PFAs such as PFNA (perfluorononanoic acid) and PFOA (perfluorooctanoic acid). The initial reactions were performed at 25 °C, using two equivalents of sodium dispersion per fluorine atom.
The strong carbon-fluorine bond was broken down and converted into sodium fluoride (NaF). The conversion led to a 67 % yield of NaF from PFAs after 12 hours, which increased to 78 % after 24 hours for both PFNA and PFOA. An increase in the concentration of sodium dispersion to 5 equivalents leads to a boost in the production of NaF. The yields for 5 equivalents of sodium dispersion were recorded as 89 % and 90 % respectively, for 24 hours and 48 hours.3
The method proved useful for polymeric and non-polymeric PFAs, leading to complete degradation. The degradation process requires at least 24 to 48 hours, depending on the PFA substrate; however, complete degradation has been recorded within 48 hours. This makes the sodium dispersion method an industrially viable technique for commercially available PFAs.
Pulsed Electrolysis Process for Aqueous Defluorination of PFAs
In a recent research article, experts from the US developed a method for aqueous defluorination of PFAs using aqueous film-forming foam (AFFF). The AFFF are a part of [NiFe]–(OH)2–hydrophilic carbon fiber paper anodes that lead to complete defluorination of PFAs by ultraviolet (UV) light-assisted electrocatalytic reactions. The [NiFe]–(OH)2 catalyst is affordable and highly stable, making it a preferred choice. The anodic potential is crucial for carbon-fluorine bond cleavage caused by the deep UV process's generation of O- radicals.
The electrolyte used for pulsed electrolysis is LiOH, which facilitates fluoride removal at the anode. The experts integrated a brief cathodic potential pulse with the recurring long-term anodic pulse, as the electrostatic repulsion facilitates C-F bond breaking, aiding in the defluorination of PFAs.
The experts reported complete defluorination of PFAs in aqueous 8.0 M LiOH electrolyte containing the AFFF, which was electrolyzed by laser-synthesized [Ni0.75Fe0.25]–(OH)2 nanosheets. The optimum potential modulation time was 30 seconds, with the technique involving 120 cycles of pulsed electrolysis.
The experts applied an anodic potential of 1.6 VRHE for 30 seconds, followed by a cathodic pulse of 1.74 VRHE. When the number of cycles was increased to 150, complete defluorination was recorded with an increase in energy requirement. Furthermore, decreasing the number of cycles to 60 reduced the defluorination rate to 49 %.4 The materials and substances used in defluorination are widely available, making the process practical, viable, and highly efficient.
Branched Organic PFA Defluorination using Vitamin B12 with Zero-valent Zinc (ZVZ) or Zero-Valent Iron (ZVI)
Among the different types of PFAS, organic PFAS like PFOA are among the most persistent pollutants. In a recent study, experts investigated the defluorination of branched PFOA using naturally present Vitamin B12 in combination with ZVZ or ZVI. The experiments were performed inside an anaerobic tent using sealable borosilicate flasks with a 13 mm internal diameter opening.
The researchers used vitamin B12 as an electron shuttle in reduced states (Co(I) and Co(II)). Technical grade PFOA with concentrations of 100 mg/L 50Molar concentration of VB12 in 20 mL anoxic MilliQ water was present in the reaction flask. The operating temperature was 70 °C. The ZVZ-VB12 reactant system led to efficient defluorination, while the ZVI-VB12 system demonstrated a weaker defluorination activity.
The ZVZ-VB12 system led to 33.450 µm fluoride release after 50 days, with several branched-PFOA isomers degrading completely within 10 days. However, the ZVI-VB12 system only led to a fluoride release of 16.5 µm after 50 days, with no visible degradation of any branched chain PFOA isomers.
C8H15O2 is released upon complete defluorination of PFOA; however, its absence represents only partial defluorination.5 The article has highlighted the importance of ZVZ-VB12 systems for the complete defluorination of highly complex branched-chain PFOA, while ushering us into a new era where destruction of highly complex branched PFOA can be done using sustainable systems.
Key Steps and the Future
The defluorination of PFAs is a major research area for the future, with governments and organizations making key progress in this regard.
Last year, the United States Environmental Protection Agency updated the 2021 PFAS roadmap. The roadmap enforces strict and legally enforceable rules for ensuring safe levels of PFAs in water bodies, safeguarding the health of over 100 million people and protecting the environment.
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EPA has officially labelled nine different types of PFAs, like PFOA and PFOS, as highly toxic, hazardous chemicals, allowing for the development of a highly efficient and cost-effective contaminant removal framework. The EPA has also updated the Regional Screening Levels and Regional Removal Management Level tables, aiding in the cleanup of different PFAs like PFOA and PFOS.
Another key milestone was the development of a detailed guideline as an update to the 2020 document on eco-friendly destruction and disposal of PFA-incorporated construction materials.6 These steps highlight that the defluorination of PFAs is critical to ensuring human safety, and significant investments are being made all over the world to accelerate the decontamination efforts.
References and Further Reading
- U.S. Food and Drug Administration. (2025). Per- and Polyfluoroalkyl Substances (PFAS). Environmental Contaminants in Food. [Online]. Available at: https://www.fda.gov/food/environmental-contaminants-food/and-polyfluoroalkyl-substances-pfas [Accessed on: September 03, 2025].
- National Institute of Environmental Health Sciences. (2025). Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS). Environmental Agents. [Online]. Available at: https://www.niehs.nih.gov/health/topics/agents/pfc [Accessed on: September 03, 2025].
- Araki, T. et al. (2025). Room-temperature defluorination of PTFE and PFAS via sodium dispersion. Nat. Commun. 16, 6526. Available at: https://doi.org/10.1038/s41467-025-61819-6
- Meng, Z. et. al. (2025). Complete aqueous defluorination of PFAS in aqueous film-forming foam (AFFF) by pulsed electrolysis with tailored potential modulation. RSC Advances, 15(11), 8287-8292. Available at: https://doi.org/10.1039/D4RA08214A
- Sun, J. et. al. (2025). Characterization of PFOA isomers from PFAS precursors and their reductive defluorination. Water Research, 268, 122717. Available at: https://doi.org/10.1016/j.watres.2024.122717
- United States Environmental Protection Agency (2024). EPA’s PFAS Strategic Roadmap: Three Years of Progress. [Online]. Available at: https://www.epa.gov/system/files/documents/2024-11/epas-pfas-strategic-roadmap-2024_508.pdf [Accessed on: September 04, 2025].
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