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 both humans and animals which poses a problem due to their wide distribution and persistency. Another problem concerns the remediation of PFAS, where the substances ends up circulating between the different disposal types (landfills, wastewater treatment and incineration). Active methods are therefore needed to remove or retain the contaminants. Some examples of these remediation technologies can be biomaterials, organoclays and more advanced methods such as activated carbon and ion exchange. The more advanced being suited for remediation of drinking water. In this study, the sorption efficiency of two pine bark fractions has been studied and also compared to the efficiency of activated carbon. The evaluation was done for both target analysis (PFAS-11) and non-specific analysis of extractable organofluorine (EOF) compounds in contaminated water from a hazardous waste management facility. The two pine bark fractions indicated similar sorption efficiencies, for both the PFAS-11 and the EOF compounds. The sorption efficiency ranged from 10% up to 75% for perfluorinated sulfonic acids (PFSA) and from below zero up to 40% for perfluorinated carboxylic acids (PFCA). A general pattern can be seen, the sorption efficiency increases with increasing length of the PFAS chain. The activated carbon had a higher sorption efficiency, where the majority of PFAS had an average sorption of 100%. In comparison, the PFAS-11 and total EOF analysis displayed high concentrations of unidentified EOF compounds. These compounds indicated a negative 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 rough remediation of long-chain PFAS (≥8C), but further studies on the sorption of unidentified fluorinated organic compounds are of interest.

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 studies on the sorption of unidentifiedfluorinated organic compounds are of interest.Keywords:

Per- and polyfluoroalkyl substances (PFAS) have been manufactured and used in differentapplications for several decades, including food packaging materials. During the last 20 yearsthese compounds have been acknowledged as hazardous for humans and the environment, anddifferent regulations on PFAS have been established on both national and international levels.Companies started to phase-out long-chain PFAS, including both PFOA and PFOS, around 20years ago. Since PFAS are persistent, this cause concerns both for our health and theenvironment, as well as possible PFAS contamination in new products due to the recycling ofmaterials. The aim of this study was to find an effective method to extract PFAS from differentfood packaging materials; analyze the samples for their extractable organofluorine (EOF)content using combustion ion chromatography; as well as analyze targeted PFAS in the samplesusing ultra-high performance liquid chromatography tandem mass spectrometry. The findingsof this study suggest that none of the selected samples had EOF contents above the Danishindicator value of 20 mg/kg dw TOF set to determine whether PFAS has been intentionallyadded to a material, and that only two samples exceeded the limit of detection for EOF. Atakeaway bowl made out of 100% sugarcane contained the highest EOF content while the outerpackaging of a cereal box contained the second highest EOF. Both PFOA and PFOS, alongwith other long-chain PFAS were detected in a majority of the samples. The lowest total PFASconcentrations when analyzing for targeted PFAS was detected in the sugarcane take awaybowl. The highest total PFAS concentration was detected in an egg carton, followed by theouter packaging of a cereal box (same as above) and the outer box of a waffle mix. The targetedPFAS was detected in almost all samples, with PFNA and 6:2 diPAP being the most frequentlydetected PFAS. PFCAs, PFSAs, FTSAs, FOSAAs and PAPs were detected in a majority of thesamples. The highest concentrations were measured for diSAmPAP in a majority of thesamples. Mass balance calculations of the sugarcane bowl showed that the targeted PFAS onlyaccounted for 0.04% of the extractable organofluorine content. In conclusion, none of thesamples displayed EOF contents higher than the Danish indicator value, suggesting that noneof the samples were intentionally treated with PFAS. However, targeted PFAS analysis of thesesamples showed that they still contain PFAS, that could be further recycled along with therecycling of paper and board food packaging materials. Considering the persistence of PFASand that these compounds can remain in the recycling chain, with the risk of also being releasedinto the environment, it is of importance that PFAS is not introduced in any of the stages in apaper or board containers life cycle.

Per- and polyfluorinated substances (PFAS) are compounds that consist of a carbon chainbackbone that is partially or entirely fluorinated, with an addition of a functional group. SomePFAS are known as persistent organic pollutants (POPs) and have therefore been drawing a lot ofattention as well as increased concerns. PFAS have been detected in humans, wildlife and theenvironment and some have exhibited toxic effects such as hepatotoxicity, immunotoxicity,reproductive toxicity and endocrine disruption as well as being persistent and bioaccumulative.Serum, plasma and whole blood have been used as biomonitoring matrices in many studies toevaluate human exposure to PFAS. Restrictions have been applied to some PFAS, but thesecompounds are still ubiquitous. This study will investigate the performance (recovery, matrixeffect (ME) in terms of intra-/inter-day repeatability) of ion-pair extraction (IPE) and solid phaseextraction with weak anion exchange (SPE-WAX). The extraction methods were adapted fromliterature and 13 PFAS were selected for this work based on prior biomonitoring studies. Thetarget PFAS content was analyzed with liquid chromatography coupled with tandem massspectrometry (LC-MS/MS). The extraction methods were also compared for extractableorganofluorine (EOF) extraction in terms of blank levels as well as the amount extracted withdifferent methods; the EOF content was measured with combustion ion chromatography (CIC).The EOF levels were used to estimate the amount of unidentified organofluorine (UOF), to avoidunderestimating potential health hazards. Samples extracted using IPE had an average ionizationenhancement of 9%, while SPE-WAX showed an average ionization suppression of -1%. SPEWAXshowed higher average recoveries for procedural blanks (78%), horse serum (96%) andhuman serum (95%) in comparison to IPE (69%, 36%, 88%, respectively). The CIC analysis forEOF content was observed to be below MDL (<50 ng/mL F) with some contaminations observedin the procedural blanks.