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- Fredriksson, Felicia, 1993-, et al.
(author)
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A Pilot Study of the Fluorinated Ingredient of Scotchgard Products and Their Levels in WWTP Sludge and Landfill Leachate from Sweden
- 2020
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Reports (other academic/artistic)abstract
- This study performed by Örebro University on behalf of the Swedish Environmental Agency aims at assessing the occurrence and levels of the newly identified side-chain fluorinated polymers from an environmental perspective. The aims of present study are 1) to develop instrumental and extraction methods to measure the active ingredient of two Scotchgard products (two side-chain fluorinated polymers, hereafter referred to as Pre-2002 and Post-2002) in sludge and leachate samples from Swedish wastewater treatment plants and landfills; 2) to evaluate if Pre-2002 and Post-2002 may be responsible for the unidentified organofluorine in the sludge samples from our previous screening study reporting extractable organofluorine (EOF); and 3) to conduct a mass balance analysis on EOF and sum of 93 per- and polyfluoroalkyl substances (PFAS) including Pre-2002 and Post-2002 in the sludge and landfill leachate samples to assess the levels of unidentified EOF that potentially are other polymeric or non-polymeric PFAS.Levels of Pre-2002 and Post-2002 and EOF are reported for sludge samples from four wastewater treatment plants (Bergkvara in Torsås, Gässlösa in Borås, Henriksdal in Stockholm, and Öhn in Umeå) collected in 2015, and leachate samples from three different landfills (Atleverket in Örebro, Hässleholm Kretsloppscenter in Hässleholm, and Flishult in Vetlanda). Sludge samples from Gässlösa wastewater treatment plant collected between 2004 and 2016 (excluding 2005 and 2006) were analyzed to assess any temporal trends of the two side-chain fluorinated polymers (Pre-2002 and Post-2002). The present investigation reported levels of both Pre-2002 and Post-2002 in all sludge samples (158-2618 ng/g d.w.). Levels of Pre-2002 were always higher than those of Post-2002 in the same samples. A declining trend was observed for Pre-2002 in sludge samples from Gässlösa but no clear trend was noted for Post-2002. The concentrations of the Pre-2002 and Post-2002 in sludge were higher than the sum of 83 PFAS analyzed in the previous screening study. No relationship between number of people that the wastewater treatment plants served and the concentrations of EOF and Pre-2002 and Post-2002 could be observed. The concentrations of both EOF and Pre-2002 and Post-2002 seem to be more related to the types of industry located in that area. Only three of the five leachate samples showed detectable levels of Pre-2002. Post-2002 was not detected in any of the landfill leachates. The low levels could be due to that both compounds are strongly sorbed to particles, which indicates the fate and distribution of these compounds. For both the sludge and leachate samples, the quantified levels of Pre-2002 and Post-2002 only contributed to a minor part of the EOF. A high proportion of unknown EOF still remains and may be related to other polymeric or non-polar PFAS.
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| 2. |
- Fredriksson, Felicia, 1993-, et al.
(author)
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Analysis and characterization of novel fluorinated compounds used in surface treatments products
- 2022
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In: Chemosphere. - : Pergamon Press. - 0045-6535 .- 1879-1298. ; 302
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Journal article (peer-reviewed)abstract
- Side-chain fluorinated polymers are speculated to be potential precursors to other non-polymeric aliphatic per- and polyfluoroalkyl acids (PFAAs). Limited knowledge of environmental occurrence of this compound class is partly due to lack of structural information and authentic standards. In this study, two novel fluorinated compounds, suspected to be side-chain fluorinated copolymers used in two commercial technical mixtures (Scotchgard™ Pre-2002 formulation and Scotchgard™ Post-2002 formulation) were analyzed and characterized in order to provide information to facilitate detection and quantification. The commercial mixtures were analyzed using tandem mass spectrometry and high-resolution mass spectrometry; besides already reported C4- and C8-fluoroalkylsulfonamido (FASA) side-chains, a proposed structure was determined for the perfluorooctane (C8) sulfonamide-urethane copolymer in the Pre-2002 formulation. Structural isomers were also observed for C4- and C8-FASA-based copolymers. Total fluorine analysis revealed that the Scotchgard™ Pre-2002 Formulation contained a fluorine content of 0.5% and 1.8% for the Scotchgard™ Post-2002 Formulation. The equivalent FASA side-chain content was determined to be 0.8% for Pre-2002 and 3.1% for Post-2002. Both C4- and C8-FASA-based copolymers underwent hydrolysis and oxidation and were transformed to their respective perfluoroalkyl side chain, which suggest that transformation products can be analyzed for example after total oxidizable precursor (TOP) assay. Both compounds were shown to strongly sorb to sediment particles, which also gives indications about their environmental fate and transport pathways.
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| 3. |
- Fredriksson, Felicia, 1993-
(author)
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Analysis of fluoroalkyl sulfonamide (FASA) based copolymers : An indirect source of non-polymeric PFAS
- 2023
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Doctoral thesis (other academic/artistic)abstract
- Per- and polyfluoroalkyl substances (PFAS) are an extensive group of anthropogenic compounds and are of global concern due to their negative effects on the environment and humans. Most environmental research reports non-polymeric PFAS, leading to a scarce understanding of polymeric PFAS, despite their large share on the global market.In this thesis, two fluoroalkyl sulfonamide (FASA)-based copolymers were studied to gain knowledge regarding their chemical characterization, occurrence, and fate. The main objectives were to provide analytical methods to analyze the FASA-based copolymers in sludge in relation to non-polymeric PFAS and extractable organo-fluorine (EOF) and to study their fate to the arable land when sludge is used as a fertilizer.The results revealed that the FASA-based copolymers were present in all sludge samples and their levels contributed to between 2 and 6 % of the total PFAS. Using two complementary extraction methods, both polymeric and non-polymeric PFAS were captured. However, more than 90% of the EOF belongs to unidentified origin. These results indicate the importance of extending the analysis of polymeric PFAS in environmental research.Further, elevated levels in sludge-amended soil of the C8-FASA-based copolymer were seen, illustrating sludge to be a potential source of C8-FASA-based copolymer to the environment. Both copolymers were transformed into non-polymeric PFAS in earthworms. This thesis provides evidence that these FASA-based copolymers are of concern, both as a direct emission and indirect source of non-polymeric PFAS to the environment.
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| 6. |
- Fredriksson, Felicia, 1993-, et al.
(author)
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Per- and polyfluoroalkyl substances (PFAS) in sludge from wastewater treatment plants in Sweden : First findings of novel fluorinated copolymers in Europe including temporal analysis
- 2022
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In: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 846
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Journal article (peer-reviewed)abstract
- Thousands of per- and polyfluoroalkyl substances (PFAS) are on the global market, while only a minor proportion is monitored regularly in the environment. Wastewater treatment plants (WWTPs) have been suggested to be a point source for PFAS to the environment due to emission of effluent and sludge. In this study, 81 PFAS including two rarely studied perfluoroalkyl sulfonamide-based (FASA) copolymers were analyzed in sludge samples to understand the usage of PFAS in the society. Sludge samples (n = 28) were collected at four WWTPs in Sweden between 2004 and 2017. The total levels of 79 measured PFAS were between 50 and 1124 ng/g d.w. All sludge samples showed detectable levels of both C8- and C4-FASA-based copolymers. The concentrations of the FASA-based copolymers were proposed to be reported in fluorinated side-chain equivalents (FSC eq.), in order to compare the levels of the copolymers with the other neutral and anionic PFAS, as no authentic standards were available. The concentrations of the FASA-based copolymers in sludge were between 1.4 and 22 ng FSC eq./g d.w. A general predomination of precursor and intermediate compounds was observed. A lower contribution of perfluoroalkyl carboxylic acids was noted for the WWTPs more influenced by domestic emission when compared with more influenced by industrial emission. An overall declining trend in the total PFAS concentration was seen between the years 2004 and 2017. The present study observed a shift from the C8-based chemistry toward shorter chain lengths, included a declining trend for C8-FASA-based copolymer over the entire study period. These findings further demonstrate the occurrence of side-chain fluorinated copolymers in Sweden and that sludge is a useful matrix to reflect the usage of PFAS in society and the potential for environmental exposure.
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| 7. |
- Kärrman, Anna, 1975-, et al.
(author)
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PFASs in the Nordic environment : Screening of Poly- and Perfluoroalkyl Substances (PFASs) and Extractable Organic Fluorine (EOF) in the Nordic Environment
- 2019
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Reports (peer-reviewed)abstract
- This report describes a screening study of in all ninety-nine conventional and emerging per- and polyfluoroalkyl substances (PFASs) in the Nordic environment. In addition, extractable organic fluorine (EOF) was analysed. The latter can provide the amount, but not identity, of organofluorine in the samples, which in turn can be used to assess the mass balance between known and unknown PFASs. The study was initiated by the Nordic Screening Group and funded by these and the Nordic Council of Ministers through the Chemicals Group. A total of 102 samples were analyzed in this study, including bird eggs, fish, marine mammals, terrestrial mammals, surface water, WWTP effluents and sludge, and air. Samples were collected by institutes from the participating countries and self-governing areas; Denmark, Faroe Islands, Finland, Greenland, Iceland, Norway, and Sweden.
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| 8. |
- Ruyle, Bridger J., et al.
(author)
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Interlaboratory Comparison of Extractable Organofluorine Measurements in Groundwater and Eel (Anguilla rostrata) : Recommendations for Methods Standardization
- 2023
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In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 57:48, s. 20159-20168
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Journal article (peer-reviewed)abstract
- Research on per- and polyfluoroalkyl substances (PFAS) frequently incorporates organofluorine measurements, particularly because they could support a class-based approach to regulation. However, standardized methods for organofluorine analysis in a broad suite of matrices are currently unavailable, including a method for extractable organofluorine (EOF) measured using combustion ion chromatography (CIC). Here, we report the results of an international interlaboratory comparison. Seven laboratories representing academia, government, and the private sector measured paired EOF and PFAS concentrations in groundwater and eel (Anguilla rostrata) from a site contaminated by aqueous film-forming foam. Among all laboratories, targeted PFAS could not explain all EOF in groundwater but accounted for most EOF in eel. EOF results from all laboratories for at least one replicate extract fell within one standard deviation of the interlaboratory mean for groundwater and five out of seven laboratories for eel. PFAS spike mixture recoveries for EOF measurements in groundwater and eel were close to the criterion (±30%) for standardized targeted PFAS methods. Instrumental operation of the CIC such as replicate sample injections was a major source of measurement uncertainty. Blank contamination and incomplete inorganic fluorine removal may introduce additional uncertainties. To elucidate the presence of unknown organofluorine using paired EOF and PFAS measurements, we recommend that analysts carefully consider confounding methodological uncertainties such as differences in precision between measurements, data processing steps such as blank subtraction and replicate analyses, and the relative recoveries of PFAS and other fluorine compounds.
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