China
Africa
Explore chapters and articles related to this topic
Landfills as Sources of PFAS Contamination of Soil and Groundwater
Published in David M. Kempisty, LeeAnn Racz, Forever Chemicals, 2021
Nanthi Bolan, Son A. Hoang, Yubo Yan, Sammani Ramanayaka, P. Koliyabandara, Gayathri Chamanee, Hasintha Wijesekara, Raj Mukhopadhyay, Binoy Sarkar, Meththika Vithanage, M. B. Kirkham
There are thousands of various PFAS, and more than 600 compounds are used for industrial applications and domestic purposes (US EPA, 2020). In addition to the domestic products listed above, PFAS are included in food contact papers, microwave popcorn bags, carpets, outdoor clothings, cosmetics, and water-resistant upholstery. Textiles, surfactants, insecticides, aqueous film-forming foams, lubricants, semiconductors, and metal plating are industrial products or processes that use PFAS at varying contents and concentrations (Herzke et al., 2012; Kotthoff et al., 2015; Benskin et al., 2012a; Wei et al., 2019). High PFAS levels have been recorded in ski waxes (up to ~2000 μg/kg PFOA) (perfluorooctanoic acid), leather samples (up to ~200 μg/kg PFBA and ~ 120 μg/kg PFBS) (perfluorobutanoic acid and perfluorobutanesulfonic acid), outdoor textiles (up to ~19 μg/m2 PFOA), and baking papers (up to ~15 μg/m2 PFOA) (Kotthoff et al., 2015). Fluorotelomer alcohols (FTOHs) have also been recorded in outdoor textiles (maximum levels as 379.9 μg/m2 FTOH 8:2) (an 8:2 fluorotelomer alcohol is a molecule with 8 fluorinated carbons and a 2 carbon ethyl alcohol group), cleaning agents (up to 73,000 μg/kg 8:2 FTOH), impregnating sprays (up to 719,000 μg/kg 8:2 FTOH), and non-stick cookwares (436 μg/kg) (Kotthoff et al., 2015; Herzke et al., 2012). Many of these consumer products are landfilled after their primary uses, thereby becoming a source for accumulation of PFAS in landfills.
Fluorosurfactants in Firefighting Foams
Published in David M. Kempisty, Yun Xing, LeeAnn Racz, Perfluoroalkyl Substances in the Environment, 2018
Stephen H. Korzeniowski, Robert C. Buck, David M. Kempisty, Martial Pabon
The second route most widely practiced for the synthesis of a perfluoroalkyl moiety is the fluorotelomer process (Taylor 1999; Pabon and Corpart 2002; Buck 2011, 2012). In the fluorotelomer process, tetrafluoroethylene (TFE) is oligomerized with perfluoroethyl iodide (PFEI) (CF3CF2I), yielding a mixture of exclusively linear, even-carbon-number perfluoroalkyl iodides that are commonly called Telomer A. The fluorotelomer chain length could range up to n = 20, but was primarily n = 6, 8, 10, and 12, with 6 and 8 predominant in commercial products. Ethylene is then inserted into Telomer A to make Telomer B, perfluoroalkyl ethyl iodide raw material, which may then be reacted to make fluorotelomer alcohol raw material and/or acrylate/methacrylate monomers. These raw materials or other types are then used to manufacture fluorosurfactants, as shown in Figure 1.2(b). Historic fluorotelomer-based fluorosurfactants contained mainly n = 6 (C6) and n = 8 (C8) perfluoroalkyl moieties (CnF2n+1–), with the majority being C6. As the major global fluorotelomer manufacturers have fulfilled their commitment to no longer make long-chain C8 chemistry (USEPA 2010), the short-chain C6 fluorotelomer-based fluorosurfactants are presently made and used.
Uptake, accumulation and metabolism of PFASs in plants and health perspectives: A critical review
Published in Critical Reviews in Environmental Science and Technology, 2021
Xingchun Jiao, Qingyang Shi, Jay Gan
Fluorotelomer alcohols (FTOHs), with even-numbered fluorocarbon chains and an ethanol moiety, are used in the production of several polymers (Butt et al., 2014). FTOHs have been reported to biotransform to PFOA and a variety of other PFCAs in the environment (Dinglasan et al., 2004).