TY - CONF A1 - Vogel, Christian A1 - Roesch, Philipp A1 - Wittwer, Philipp A1 - Huthwelker, T. A1 - Simon, Franz-Georg T1 - Fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy as a novel tool for the characterization of per- and polyfluoroalkyl substances (PFAS) in soils and sludges N2 - Per- and polyfluoroalkyl substances (PFAS) have been used extensively in the past because of their inert chemical character and resistance to degradation by environmental influences. Since the beginning of their commercial use, PFAS have been widely exposed to the environment by application of PFAS in consumer products or as foaming agent in firefighting foams, thus several cases of contaminated soils sites have been reported. Since the number of known PFAS already exceeds 4700, their characterization and direct analysis is challenging given the current available techniques. Here, we introduce the novel fluorine (F) K-edge X-ray absorption near-edge structure (XANES) spectroscopy as a tool to analyze PFAS and inorganic fluorine compounds in contaminated soils and sewage sludges. While F K-edge bulk-XANES spectroscopy provide us information on the overall fluorine bonding in a sample micro X-ray fluorescence (XRF) in combination with F K-edge micro-XANES spectroscopy can also detect minor fluorine compounds and PFAS hotspots in investigated soils and sludges. Additionally, we used the combustion ion chromatography (CIC) to analyze the total amount of all PFAS as a sum parameter (extractable organic fluoride: EOF) in soils and sewage sludges. During combustion in the CIC, the PFAS in the sample get destroyed at temperatures of approx. 1000 °C and converted in inorganic fluorides that subsequently gets quantified by ion chromatography. Thus, for the first time we successfully combined F K-edge XANES spectroscopy and CIC as analytical tools to detect and quantify PFAS contaminants in soils and sewage sludges. T2 - SETAC Europe CY - Online meeting DA - 03.05.2021 KW - Sewage sludge KW - Combustion ion chromatography KW - Soil KW - X-ray absorption near-edge structure (XANES) spectroscopy PY - 2021 AN - OPUS4-52563 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogel, Christian A1 - Krüger, O. A1 - Gentzmann, Marie A1 - Adam, Christian T1 - Can we use passive samplers for the determination of chromium(VI) in phosphorus fertilizers? N2 - Phosphorus (P) fertilizers from secondary resources became increasingly important in the last years. However, these novel P-fertilizers can also contain toxic pollutants. Chromium in its hexavalent state (Cr(VI)) is regulated with low limit values for agricultural products due to its high toxicity, but the determination of Cr(VI) in these novel fertilizer matrices can be hampered by redox processes that lead to false results. Thus, we applied the passive sampler technique Diffusive Gradients in Thin-films (DGT) for the determination of Cr(VI) in fertilizers and compared the results with the standard wet chemical extraction method (German norm DIN EN 15192) and Cr K-edge X-ray absorption near-edge structure (XANES) spectroscopy. We determined an overall good correlation between the wet chemical extraction and the DGT method. DGT was very sensitive and in most cases selective for the analysis of Cr(VI) in P-fertilizers. However, hardly soluble Cr(VI) compounds cannot be detected with the DGT method since only mobile Cr(VI) is analyzed. Furthermore, Cr K-edge XANES spectroscopy showed that the DGT binding layer also adsorbs small amounts of mobile Cr(III) compounds which leads to overestimated Cr(VI) values. The results of certain types of P-fertilizers containing mobile Cr(III) or partly immobile Cr(VI), showed that optimization of the DGT method is required to avoid over- or underestimation of Cr(VI). T2 - International Passive Sampling Workshop (IPSW) 2021 virtual CY - Online meeting DA - 04.11.2021 KW - Phosphorus KW - Sewage sludge KW - Chromium KW - Fertilizer PY - 2021 AN - OPUS4-53699 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -