Scientific Overview of PFAS and Drinking Water | AAAS EPI Center
Figure 2 – Examples of Primary and Secondary Sources of PFAS in the Environment
AFFF is used to extinguish flammable liquid fires. The largest stocks of AFFF are stored at commercial and private airports, military sites, chemical plants, and aboveground petroleum storage tank facilities. Many fire departments still use AFFF for training and emergency response. When AFFF is used, runoff may enter sewer or stormwater systems. Industrial facilities and incineration facilities can release PFAS into the environment through liquid discharge, solid waste, disposal of contaminants in soil, and/or air emissions . Industrial facilities in the U.S. have largely phased out PFOS and PFOA but continue to use short-chain PFAS in some applications. Incineration is one of the main methods used to destroy PFAS. Incineration facilities may discharge PFAS into the air during the incineration of materials if they are not heated to the correct destruction temperature. These materials include media and resin used during the treatment of PFAS in drinking water facilities 23,24 . PFAS-containing air emissions may deposit PFAS back into the environment through settling and precipitation. Research is ongoing to characterize PFAS behavior in air emissions and determine the conditions required for the destruction of PFAS during high-temperature incineration. Additional research is needed to establish standard methods for PFAS testing in air and enhance our understanding of PFAS emissions and control options. Wastewater treatment plant effluent and biosolids can contain PFAS. Because PFAS are used in many consumer products, they can be present in the wastewater conveyed by sewer systems to municipal wastewater treatment plants (WWTPs). Additional PFAS sources in WWTPs include AFFF runoff and PFAS- contaminated industrial waste 25 . WWTPs are not equipped to remove significant levels of PFAS, which then may be present in treated wastewater that is discharged into surface waters or in the sewage sludge produced during the wastewater treatment process. This sludge is either disposed of or further treated to form biosolids, which can be applied to agricultural land as fertilizer. Landfills receive a wide range of products containing PFAS, such as non-stick cookware, fast food wrappers, furniture, and water-resistant clothing. As rainwater filters down through landfills, it accumulates PFAS and
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