Utility of bark chips for removal of fluorinatedorganic compounds in water samples at a hazardouswaste management facility

Per- and polyfluoroalkyl substances (PFAS) are synthetic compounds that have beenaround since 1940. They can be used in a variety of products such as fire-fighting foam,food packaging and cosmetic products. Many PFAS have potential toxic effects on bothhumans and animals which poses a problem due to their wide distribution and persistency.Another problem concerns the remediation of PFAS, where the substances ends upcirculating between the different disposal types (landfills, wastewater treatment andincineration). Active methods are therefore needed to remove or retain the contaminants.Some examples of these remediation technologies can be biomaterials, organoclays andmore advanced methods such as activated carbon and ion exchange. The more advancedbeing suited for remediation of drinking water. In this study, the sorption efficiency oftwo pine bark fractions has been studied and also compared to the efficiency of activatedcarbon. The evaluation was done for both target analysis (PFAS-11) and non-specificanalysis of extractable organofluorine (EOF) compounds in contaminated water from ahazardous waste management facility. The two pine bark fractions indicated similarsorption efficiencies, for both the PFAS-11 and the EOF compounds. The sorptionefficiency ranged from 10% up to 75% for perfluorinated sulfonic acids (PFSA) and frombelow zero up to 40% for perfluorinated carboxylic acids (PFCA). A general pattern canbe seen, the sorption efficiency increases with increasing length of the PFAS chain. Theactivated carbon had a higher sorption efficiency, where the majority of PFAS had anaverage sorption of 100%. In comparison, the PFAS-11 and total EOF analysis displayedhigh concentrations of unidentified EOF compounds. These compounds indicated anegative sorption, which might imply that non-targeted PFAS or other fluorinated organic compounds desorb from the bark. Therefore, the pine bark might be suitable as a roughremediation of long-chain PFAS (≥8C), but further studie