TY - JOUR A1 - Roesch, Philipp A1 - Vogel, Christian A1 - Wittwer, Philipp A1 - Huthwelker, T. A1 - Borca, C. A1 - Sommerfeld, Thomas A1 - Kluge, Stephanie A1 - Piechotta, Christian A1 - Kalbe, Ute A1 - Simon, Franz-Georg T1 - Taking a Look at the Surface: µ-XRF Mapping and Fluorine K-edge µ-XANES Spectroscopy of Organofluorinated Compounds in Environmental Samples and Consumer Products N2 - For the first time, µ-X-ray fluorescence (µ-XRF) mapping combined with fluorine K-edge µ-X-ray absorption near-edge structure (µ-XANES) spectroscopy was applied to depict per- and polyfluoroalkyl substances (PFAS) contamination and inorganic fluoride in samples concentrations down to 100 µg/kg fluoride. To demonstrate the matrix tolerance of the method, several PFAS contaminated soil and sludge samples as well as selected consumer product samples (textiles, food contact paper and permanent baking sheet) were investigated. µ-XRF mapping allows for a unique element-specific visualisation at the sample surface and enables localisation of fluorine containing compounds to a depth of 1 µm. Manually selected fluorine rich spots were subsequently analysed via fluorine K-edge µ-XANES spectroscopy. To support spectral interpretation with respect to inorganic and organic chemical distribution and compound class determination, linear combination (LC) fitting was applied to all recorded µ-XANES spectra. Complementarily, solvent extracts of all samples were target-analysed via LC-MS/MS spectrometry. The detected PFAS sum values range from 20 to 1136 µg/kg dry weight (dw). All environmentally exposed samples revealed higher concentration of PFAS with a chain length >C8 (e.g. 580 µg/kg dw PFOS for Soil1), whereas the consumer product samples showed a more uniform distribution with regard to chain lengths from C4 to C8. Independent from quantified PFAS amounts via target analysis, µ-XRF mapping combined with µ-XANES spectroscopy was successfully applied to detect both point-specific concentration maxima and evenly distributed surface coatings of fluorinated organic contaminants in the corresponding samples. KW - PFAS KW - XRF KW - LC-MS/MS KW - XANES KW - Fluoride KW - Soil PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576109 DO - https://doi.org/10.1039/D3EM00107E SN - 2050-7887 SP - 1 EP - 12 PB - Royal Society of Chemistry AN - OPUS4-57610 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Roesch, Philipp A1 - Wittwer, Philipp A1 - Sommerfeld, Thomas A1 - Riedel, Maren A1 - Leube, Peter A1 - Kalbe, Ute A1 - Schoknecht, Ute A1 - Simon, Franz-Georg T1 - Per- and Polyfluoroalkyl Substances (PFAS) in Ski Waxes and Snow from Cross-Country Skiing in Germany - Comparative study of Sum Parameter and Target Analysis N2 - Per- and polyfluoroalkyl substances (PFAS) are often environmentally exposed via discharge through human consumer products, such as ski waxes. In our study we analyzed various ski waxes from the 1980s and 2020s, to determine both the sum parameter values total fluorine (TF), extractable organically bound fluorine (EOF), hydrolysable organically bound fluorine (HOF) as well as targeted PFAS analysis. This showed that modern high-performance waxes contain up to 6 % TF, but also PFAS-free labelled ski waxes contain traces of PFAS with EOF/HOF values in the low mg kg-1 range. With the ban of all fluorine-based waxes with the start of the 2023/2024 winter season this will probably change soon. Moreover, we applied our analysis methods to snow samples from a frequently used cross country ski trail (Kammloipe) in the Ore Mountain region in Germany, assessing the potential PFAS entry/discharge through ski waxes. Melted snow samples from different spots were analyzed by the adsorbable organically bound fluorine (AOF) sum parameter and PFAS target analysis and confirmed the abrasion of the ski waxes into the snow. Moreover, on a PFAS hotspot also soil samples were analyzed, which indicate that PFAS from the ski waxes adsorb after snow melting into the soil. KW - Combustion Ion Chromatography KW - Per- and Polyfluoroalkyl substances (PFAS) KW - Consumer Products PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612760 DO - https://doi.org/10.1016/j.hazadv.2024.100484 VL - 16 SP - 1 EP - 5 PB - Elsevier B.V. AN - OPUS4-61276 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Roesch, Philipp A1 - Schinnen, Andrea A1 - Riedel, Maren A1 - Sommerfeld, Thomas A1 - Sawal, G. A1 - Bandow, N. A1 - Vogel, Christian A1 - Kalbe, Ute A1 - Simon, Franz-Georg T1 - Investigation of pH-dependent extraction methods for PFAS in (fluoropolymer-based) consumer products: A comparative study between targeted and sum parameter analysis N2 - Here, we report a comparative study of different sum parameter analysis methods for the extraction of per- and polyfluoroalkyl substances (PFAS) from manufactured consumer products, which can be measured by combustion ion chromatography (CIC). Therefore, a hydrolysis-based extraction method was further developed, which accounts for the addition of hydrolyzable covalently bound polyfluoroalkylated side-chain polymers (SFPs) to the extractable organic fluorine portion of the mass balance proposed as "hydrolyzable organically bound fluorine" (HOF). To test this hypothesis, the method was applied to 39 different consumer products containing fluoropolymers or monomeric PFAS taken from four different categories: outdoor textiles, paper packaging, carpeting, and permanent baking sheets. We also evaluated the method's efficiency by extracting four synthesized fluorotelomer polyacrylate reference compounds. The total fluorine (TF) and extractable organically bound fluorine (EOF) values were measured through CIC using established protocols. The TF values ranged from sub-ppb to %-levels, depending on the compound class. All samples showed results for hydrolyzed organofluorine (HOF) between 0.03 and 76.3 μg/g, while most EOF values were lower (150 mg kg−1, because of different diffusion properties for various PFAS, but also kinetic exchange limitations. KW - Combustion ion chromatography KW - Per- and polyfluoroalkyl substances (PFAS) KW - Sewage sludge KW - Fertilizer PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-583429 DO - https://doi.org/10.1039/d3va00178d SN - 2754-7000 VL - 2 IS - 10 SP - 1436 EP - 1445 PB - Royal Society of Chemistry (RSC) CY - London AN - OPUS4-58342 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Olbrich, Adelina-Elisa A1 - An Stepec, Biwen Annie A1 - Wurzler, Nina A1 - Terol, E. C. A1 - Koerdt, Andrea A1 - Meermann, Björn T1 - Beyond corrosion: Development of a single cell-ICP-ToF-MS method to uncover the process of microbiologically influenced corrosion N2 - The development of the microbiologically influenced corrosion ( MIC ) -specific inductively coupled plasma-time of flight-mass spectrometry ( ICP-ToF-MS ) analytical method presented here, in combination with the investigation of steel-MIC interactions, contributes significantly to progress in instrumental MIC analysis. For this, a MIC-specific staining procedure was developed, which ensures the analysis of intact cells. It allows the analysis of archaea at a single cell level, which is extremely scarce compared to other well-characterized organisms. The detection method revealed elemental selectivity for the corrosive methanogenic strain Methanobacterium -affiliated IM1. Hence, the possible uptake of individual elements from different steel samples was investigated and results showed the cells responded at a single-cell level to the different types of supplemented elements and displayed the abilities to uptake chromium, vanadium, titanium, cobalt, and molybdenum from solid metal surfaces. The methods developed and information obtained will be used in the future to elucidate underlying mechanisms, compliment well-developed methods, such as SEM-EDS, and develop novel material protection concepts. KW - Single cell KW - Microbiological influenced corrosion MIC KW - Sc-ICP-ToF-MS KW - Method development KW - Ir DNA staining approach KW - Carbon steel corrosion PY - 2022 DO - https://doi.org/10.1093/mtomcs/mfac083 SN - 1756-591X VL - 14 IS - 11 SP - 1 EP - 15 PB - Oxford University Press CY - Oxford AN - OPUS4-56254 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wen, Keqing A1 - Gorbushina, Anna A1 - Schwibbert, Karin A1 - Bell, Jérémy T1 - Microfluidic platform with precisely controlled hydrodynamic parameters and integrated features for generation of microvortices to accurately form and monitor biofilms in flow N2 - Microorganisms often live in habitats characterized by fluid flow, and their adhesion to surfaces in industrial systems or clinical settings may lead to pipe clogging, microbially influenced corrosion, material deterioration, food spoilage, infections, and human illness. Here, a novel microfluidic platform was developed to investigate biofilm formation under precisely controlled (i) cell concentration, (ii) temperature, and (iii) flow conditions. The developed platform central unit is a single-channel microfluidic flow cell designed to ensure ultrahomogeneous flow and condition in its central area, where features, e.g., with trapping properties, can be incorporated. In comparison to static and macroflow chamber assays for biofilm studies, microfluidic chips allow in situ monitoring of biofilm formation under various flow regimes and have better environment control and smaller sample requirements. Flow simulations and experiments with fluorescent particles were used to simulate bacteria flow in the platform cell for calculating flow velocity and direction at the microscale level. The combination of flow analysis and fluorescent strain injection in the cell showed that microtraps placed at the center of the channel were efficient in capturing bacteria at determined positions and to study how flow conditions, especially microvortices, can affect biofilm formation. The microfluidic platform exhibited improved performances in terms of homogeneity and robustness for in vitro biofilm formation. We anticipate the presented platform to be suitable for broad, versatile, and high-throughput biofilm studies at the microscale level. KW - Topographical pattern KW - E. coli KW - Fluorescence KW - Bacteria trapping KW - Particle velocimetry PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610450 DO - https://doi.org/10.1021/acsbiomaterials.4c00101 SN - 2373-9878 VL - 10 IS - 7 SP - 4626 EP - 4634 PB - ACS Publ. CY - Washington, DC AN - OPUS4-61045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Richter, Matthias A1 - Schühle, Florian T1 - Experimental determination of 7-day uptake rates for diffusive sampling of 86 volatile and semi-volatile organic compounds relevant for indoor air monitoring and investigation on their sensitivity to exposure time and indoor climate N2 - This study aimed to experimentally determine uptake rates for 86 indoor relevant volatile and semi-volatile organic compounds (VOC, SVOC) for the passive sampler type Perkin Elmer/Markes™ with Tenax® TA as sorbent, which was used in the German Environmental Survey on Health (GerES VI) carried out by the German Environmental Agency (UBA) in the years 2023-2024. For this purpose, single reference gas atmospheres of 76 pure VOCs (liquid at room temperature) and a group of 10 SVOCs and VOCs (solid at room temperature) were generated using two generation procedures. By exposing the samplers to individual components, it was ruled out that interactions in a mixture have a influence on the uptake rate. Another aspect was to precisely describe the methodology and the resulting uncertainties, as there are gaps in the literature in this regard. The selection of the compounds was based on the findings of the preceding GerES V study for which data was missing or needed to be verified. In each experiment, a number of six passive samplers was exposed to the test gas atmospheres in dynamically operated exposure chambers for seven days. The sensitivity of the uptake rates of a group of 10 selected VOCs to variations in exposure time, ambient temperature, and air humidity in a multi-component reference gas atmosphere was investigated. Here, a decrease in the uptake rate with the exposure time could be observed stabilising from the fifth day of exposure onwards. A significant effect of temperature and humidity on the uptake rate was not apparent. The determined uptake rates exhibit uncertainties of < 20 % for 71 substances, and < 10 % for 51 substances which are also in good agreement with the literature, if already published elsewhere. The quantity of investigated substances, the detailed description of the methodology used to determine the uptake rates complemented by the respective uncertainties, as well as the compilation of comparative data, contribute to a better assessment of the quality and relevance of such data, which had not been published before. KW - Indoor air quality KW - Volatile organic compounds KW - Uptake rates KW - Passive sampling KW - Tenax TA PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629913 DO - https://doi.org/10.1016/j.indenv.2025.100095 VL - 2 IS - 2 SP - 1 EP - 11 PB - Elsevier AN - OPUS4-62991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gentzmann, Marie A1 - Paul, Andrea A1 - Serrano, Juan A1 - Adam, Christian T1 - Understanding scandium leaching from bauxite residues of different geological backgrounds using statistical design of experiments N2 - The leaching behavior of scandium (Sc) from bauxite residues can differ significantly when residues of different geological backgrounds are compared. The mineralogy of the source rock and the physicochemical environment during bauxitization affect the association of Sc in the bauxite i.e., how Sc is distributed amongst different mineral phases and whether it is incorporated in and/or adsorbed onto those phases. The Sc association in the bauxite is in turn crucial for the resulting Sc association in the bauxite residue. In this study systematic leaching experiments were performed on three different bauxite residues using a statistical design of experiments approach. The three bauxite residues compared originated from processing of lateritic and karstic bauxites from Germany, Hungary, and Russia. The recovery of Sc and Fe was determined by ICP-OES measurements. Mineralogical changes were analyzed by X-ray-diffraction and subsequent Rietveld refinement. The effects of various parameters including temperature, acid type, acid concentration, liquid-to-solid ratio and residence time were studied. A response surface model was calculated for the selected case of citric acid leaching of Hungarian bauxite residue. The investigations showed that the type of bauxite residue has a strong influence. The easily leachable fraction of Sc can vary considerably between the types, reaching ~20–25% in German Bauxite residue and ~50% in Russian bauxite residue. Mineralogical investigations revealed that a major part of this fraction was released from secondary phases such as cancrinite and katoite formed during Bayer processing of the bauxite. The effect of temperature on Sc and Fe recovery is strong especially when citric acid is used. Based on the exponential relationship between temperature and Fe-recovery it was found to be particularly important for the selectivity of Sc over Fe. Optimization of the model for a maximum Sc recovery combined with a minimum Fe recovery yielded results of ~28% Sc recovery at <2% Fe recovery at a temperature of 60 ◦C, a citric acid normality of 1.8, and a liquid-to-solid ratio of 16 ml/g. Our study has shown that detailed knowledge about the Sc association and distribution in bauxite and bauxite residue is key to an efficient and selective leaching of Sc from bauxite residues. KW - Bauxite residue KW - Scandium KW - Leaching KW - Design of experiments KW - Red mud PY - 2022 DO - https://doi.org/10.1016/j.gexplo.2022.107041 SN - 0375-6742 VL - 2022 IS - 240 SP - 1 EP - 13 PB - Elsevier Science CY - Amsterdam AN - OPUS4-55531 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -