Removal of PFAS from Water by Plants

Abstract

Perfluorinated alkylated substances (PFAS) has been produced the last five decades as wetting agents, stain-resistant treatments, lubricants, impregnation sprays and corrosion inhibitors. Among the most common and toxic are perfluoro octane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), which are found among others in blood, soil and water. They need to be removed from water and the aim was to investigate the removal capacity by a terrestrial plant, Salix viminalis, two emergent plants, Carex rostrata and Euriophorum angustifolium and one submerged plant, Elodea canadensis. Leakage water from a landfill were treated with plants during up to 14 days. Results showed that the removal capacity was in the order: S. viminalis < E. angustifolium < C. rostrata = E. canadensis. The removal by C. rostrata and E. canadensis increased linearly with time. PFOS and PFOA decreased with 63 and 42%, respectively, in the water after 12 d treatment with C. rostrata. Both PFOS and PFOA was taken up in tissue of the C. rostrata and E. canadensis: around 9% of PFOS/PFOA was found in the plant. PFOA was more able to be translocated to the shoot than PFOS. About 5% PFOS/PFOA did disappear from the system, indicating that some of PFOS and PFOA possible had been degraded or transformed. However, no degrading enzymes, peroxidase or laccase, enzymes earlier shown to degrade PFAS, were detected in the water. One can conclude that the wetland plants were able to remove various PFAS from water and possible be used in phytoremediation.

Phytoremediation of soil contaminated with per- and polyfluoroalkyl substances (PFAS)

“…Previous studies have estimated the PFAS removal of plants. However, these studies were often performed briefly (≥14 days) or in hydroponics experimental setups (Zhang et al 2019;Sharma et al 2020;Greger et al 2021). A study of various willow cultivars also obtained removal efficiency between 2-30% in leaves of willow grown in hydroponics experiments following eight days of PFAS exposure (Sharma et al 2020).…”

The Transformation of Per- and Polyfluoroalkyl Substances in the Aquatic Environment of a Fluorochemical Industrial Park

“…In hydroponic experiments, aquatic plants displayed potential to remove PFASs from the aquatic environment [25]. Greger et al treated leakage water from a landfill with plants, and the results showed that the removal capacity of aquatic plants (42.1%) was higher than that of terrestrial plants (7.7%) [26,27]. The aquatic plant removal rate of PFOA and PFOS was more than 82% after treatment for 15 days in the study by Chen et al [28].…”