By Emma Cook, Hannah Musgrove, and Rob Dyer
UVA ChemSciComm
PFAS, also known as per- and polyfluoroalkyl substances, are a class of manmade chemicals that are found in many materials that we use every day. PFAS contain a long carbon chain that is fully saturated with fluorine atoms which repels water terminated at the end by a water-soluble head group.1 These molecules have interesting and attractive material properties due to their chemical structure. The long, fluorinated carbon chain allows these chemicals to be resistant to oil, stains, grease, and water.2 Because of this, they have been used in many common items including non-stick cookware, food packaging, clothing, and furniture since the 1950s.3 They have also been used as a component of firefighting foam. Through their widespread production and use, PFAS have found their way into the environment when disposed4 which is where they can become an issue. PFAS are known as ‘forever chemicals’ because they do not break down and instead accumulate in the environment. Because of this accumulation, people can be exposed to PFAS through drinking contaminated water, eating fish that are caught in contaminated water, ingesting contaminated soil, eating food grown or raised near places that used or made PFAS, eating food that has been packaged in material containing PFAS, and using consumer products that still contain PFAS. PFAS accumulate in the bloodstream and it has been found that most Americans (97%) have some level of PFAS in their blood.5 Importantly, it has been shown that exposure to certain levels of PFAS can cause health effects including decreased fertility, developmental effects in children, increased risk of some cancers, lowered immune response and reduced vaccine response, interference with the body’s natural hormones, and increased cholesterol levels.6
Though the original PFAS used to make Teflon were taken out of production, there are many other PFAS in production that could be impacting human and environmental health. Because of this, researchers are developing solutions for cleaning up existing PFAS and ensuring that there are better materials to use as a replacement. Ongoing research in PFAS cleanup has shown promising results in using biological solutions such as white-rot fungus and specific kinds of mircrobes for their ability to break down the fluorocarbon chains.1 Certain plants, such as hemp, may also be a useful natural solution for filtering the forever chemicals out of soil.7 For ground and wastewater PFAS removal, several techniques that use sound waves, known as sonochemistry, have been found to effectively speed up the degradation of several kinds of PFAS molecules into less toxic products.1,8,9 Mild cleaning solutions using polar aprotic solvents and detergents have been found to effectively remove and break down PFAS found on surfaces or other isolated areas.10,11
For replacing PFAS, there is no bio-friendly, single solution yet available. However, companies such as RTI International, a non-profit research institution, offer their consultation serves to help industries find more suitable alternatives to PFAS depending on how it was previously being relied on functionally. Reports can also be found that help industrial producers identify ingredient alternatives for non-essential PFAS items such as paint and coatings12, or help consumers identify products that are PFAS-free.13
There is still a lot of room for growth in PFAS removal, replacement, and policy. However, awareness of the current science and industry partners dedicated to alleviating PFAS contamination can assist in supporting and improving research in this area.
References
(1) Kucharzyk, K. H.; Darlington, R.; Benotti, M.; Deeb, R.; Hawley, E. Novel Treatment Technologies for PFAS Compounds: A Critical Review. J. Environ. Manage. 2017, 204, 757–764. https://doi.org/10.1016/j.jenvman.2017.08.016.
(2) Per- and Polyfluorinated Substances (PFAS) Factsheet. National Biomonitroring Program.
(3) Agency for Toxic Substances and Disease Registry. Per- and Polyfluoroalkyl Substances (PFAS) and Your Health. PFAS and Your Health, 2022.
(4) SWRCB - Division of Water Quality. PFAS - Frequently Asked Questions, 2020.
(5) National Institute of Health. Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS). NIH Health & Education, 2022.
(6) Our Current Understanding of the Human Health and Environmental Risks of PFAS.
(7) Christopher Tyree. Seeking Natural Solutions for a Manmade Problem. UVAToday, 2019.
(8) Hao, F.; Guo, W.; Wang, A.; Leng, Y.; Li, H. Intensification of Sonochemical Degradation of Ammonium Perfluorooctanoate by Persulfate Oxidant. Ultrason. Sonochem. 2014, 21 (2), 554–558. https://doi.org/10.1016/j.ultsonch.2013.09.016.
(9) Lei, Y.-J.; Tian, Y.; Sobhani, Z.; Naidu, R.; Fang, C. Synergistic Degradation of PFAS in Water and Soil by Dual-Frequency Ultrasonic Activated Persulfate. Chem. Eng. J. 2020, 388, 124215. https://doi.org/10.1016/j.cej.2020.124215.
(10) Brittany Trang; Yuli Li; Xiao-Song Xue; Mohamed Ateia; K. N. Houk; William R. Dichtel. Low-Temperature Mineralization of Perfluorocarboxylic Acids. Science 2022, 377 (6608), 839–845. https://doi.org/10.1126/science.abm8868.
(11) Cornelsen, M.; Weber, R.; Panglisch, S. Minimizing the Environmental Impact of PFAS by Using Specialized Coagulants for the Treatment of PFAS Polluted Waters and for the Decontamination of Firefighting Equipment. Emerg. Contam. 2021, 7, 63–76. https://doi.org/10.1016/j.emcon.2021.02.001.
(12) OECD. Per- and Polyfluoroalkyl Substances and Alternatives in Coatings, Paints and Varnishes (CPVs); OECD Series on Risk Management; Report on the Commercial Availability and Current Uses No. 70; Environment, Health and Safety, Environment Directorate, OECD.
(13) Green Scinece Policy. PFAS-Free Products. PFAS Central.