Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals formed by carbon chains where fluorine atoms replace one or more hydrogen atoms. These bonds are extremely stable and PFAS components are known to be persistent environmental contaminants. The impact of these contaminants on two geomembranes is studied. Specifically, the short-term behaviour of a linear-low density LLDPE and a high-density HDPE polyethylene geomembrane immersed in a PFAS solution at an evaluated temperature is examined after 6.5 months of ageing. Results are presented for a PFAS solution with each priority component at 20 ppm or 1 ppm, a control solution (deionized water with CaCO3 28 ppm), and an MSW leachate solution at two representative temperatures of landfills (65°C and 85°C). Results show significant depletion of oxidative induction time (OIT) due to the consumption of antioxidants present in these materials. The values obtained suggest the need to consider the potential impacts of PFAS on the performance of geomembranes used in barrier systems.
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