TY - JOUR A1 - Schoknecht, Ute A1 - Mathies, Helena A1 - Lisec, Jan T1 - Leaching and transformation of film preservatives in paints induced by combined exposure to ultraviolet radiation and water contact under controlled laboratory conditions N2 - Stormwater from urban areas can transport biocidally active substances and related transformation products from buildings into the environment. The occurrence of these substances in urban runoff depends on the availability of water, and on ultraviolet radiation exposure that causes photolytic reactions. In a systematic laboratory study, painted test specimens were exposed to either ultraviolet radiation, water contact, or a combination of both. Leaching of the biocidally active substances carbendazim, diuron, octylisothiazolinone, terbutryn, and selected transformation products of terbutryn and diuron were observed under various exposure conditions. Remaining concentrations of these substances in the paint were quantified. It was demonstrated that the distribution of active substances and transformation products in eluates and in the coatings themselves differs with exposure conditions. Strategies for environmental monitoring of biocide emissions need to consider the most relevant transformation products. However, environmental concentrations of biocidally active substances and transformation products depend on earlier exposure conditions. As a consequence, monitoring data cannot describe emission processes and predict expected leaching of biocidally active substances from buildings if the data are collected only occasionally. KW - Substance release KW - Construction products KW - Biocides KW - Transformation KW - UV radiation KW - Water contact PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532114 DO - https://doi.org/10.3390/w13172390 SN - 2073-4441 VL - 13 IS - 17 SP - 1 EP - 16 PB - MDPI CY - Basel AN - OPUS4-53211 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sanchez-Martin, Pedro A1 - Becker, Roland A1 - Toepel, J. A1 - Gorbushina, Anna T1 - An improved test for the evaluation of hydrocarbon degradation capacities of diesel-contaminating microorganisms N2 - The development of a test to evaluate the degradation of semi-volatile fuels as diesel by microorganisms is presented. This method is based on the principles described in the CEC-L-103 Standard procedure that is exclusively meant for testing the biodegradability of non-volatile lubricants. Therefore, significant modifications involve aseptic conditions for testing specific microorganisms and conducting the test in closed vessels avoiding evaporation losses, while fuel quantification using gas chromatography-flame ionization detection (GC-FID) is retained. It is suggested that the modified procedure should enable routine application for semi-volatile hydrocarbon-based fuels. GC-FID provides additionally valuable information on the alteration of fuel component patterns during biodegradation. The procedure was successfully tested using two bacteria (Pseudomonas aeruginosa and Sphingomonas sp.) and two yeasts (Moesziomyces sp. and Candida sp.) isolated from real diesel contamination cases. All tested microorganisms caused a significant degradation of diesel fuel achieving hydrocarbon degradation percentages ranging from 23% to 35%. Specific aspects on the test modification and prospects for further modification regarding targeted investigations in the field of fuel contamination by microorganisms are briefly discussed. KW - Biofouling KW - Bacteria KW - Fungi KW - CEC-L-103 KW - GC-FID KW - Reference organisms PY - 2018 DO - https://doi.org/10.1016/j.ibiod.2018.01.009 SN - 0964-8305 VL - 129 SP - 89 EP - 94 PB - Elsevier AN - OPUS4-44524 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald A1 - Borzekowski, Antje A1 - Drewitz, Tatjana A1 - Keller, Julia A1 - Pfeifer, Dietmar A1 - Kunte, Hans-Jörg A1 - Koch, Matthias A1 - Rohn, S. T1 - Biosynthesis of zearalenone conjugates by fungi N2 - Zearalenone (ZEN) and its sulfate and glucoside conjugates have been detected in (a broad variety of) food and feed commodities1. Both conjugated derivatives are formed as part of fungal or plant secondary metabolism and thus, belong to the group of modified mycotoxins2. After consumption of contaminated foodstuff, the conjugates can be hydrolyzed by human intestinal microbiota leading to liberation of ZEN that implies an underestimation of the true ZEN exposure. In order to include ZEN conjugates in routine analysis, as well as for toxicological investigation reliable standards are needed. The objective of the present study was to develop a simple and economic method for biosynthesis of ZEN conjugates. Preceding experiments on the biotransformation of ZEN by Rhizopus and Aspergillus species showed a mixed metabolite formation3. Therefore, these known ZEN conjugating fungal strains were screened for their potential to selectively synthesize the ZEN derivatives ZEN-14-sulfate (Z14S), ZEN-14-glucoside (Z14G) and ZEN-16-glucoside (Z16G). The screening was conducted by adding ZEN to liquid fungal cultures. Cultivation conditions and ZEN incubation time were varied. All media samples were analyzed for metabolite formation by HPLC-MS/MS. Z14S was exclusively formed by A. oryzae. Under optimized conditions a specific biosynthesis of Z14G by R. oryzae and Z16G by R. oligosporus was achieved. After liquid-liquid-extraction and preparative chromatographic cleanup 1H-NMR purities of ≥ 73% for Z14S, ≥ 82% for Z14G and ≥ 50% for Z16G were obtained. In addition, a consecutive biosynthesis was developed by first using Fusarium graminearum for ZEN biosynthesis on rice based liquid medium. After inactivation of Fusarium the subsequent conjugation reaction was conducted utilizing Aspergillus and Rhizopus species under the various optimized conditions. In this study an easy and cost-efficient biosynthesis for Z14S, Z14G and Z16G was developed. The developed biosynthesis could be also used for other metabolites like ZEL conjugates. Our results of the in vitro screening indicate also the formation of a ZEL-glucoside and α ZEL-sulfate as major metabolites by R. oryzae. In sum, under optimized cultivation conditions fungi can be easily utilized for a targeted and stereospecific synthesis of ZEN conjugates. T2 - 10th World Mycotoxin Forum Conference CY - Amsterdam, The Netherlands DA - 12.03.2018 KW - Mycotoxins KW - Food safety KW - Analytical standards PY - 2018 AN - OPUS4-44547 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Borzekowski, Antje A1 - Drewitz, T. A1 - Keller, Julia A1 - Pfeifer, Dietmar A1 - Kunte, Hans-Jörg A1 - Koch, Matthias A1 - Rohn, S. A1 - Maul, R. T1 - Biosynthesis and characterization of zearalenone-14-sulfate, zearalenone-14-glucoside and zearalenone-16-glucoside using common fungal strains N2 - Zearalenone (ZEN) and its phase II sulfate and glucoside metabolites have been detected in food and feed commodities. After consumption, the conjugates can be hydrolyzed by the human intestinal microbiota leading to liberation of ZEN that implies an underestimation of the true ZEN exposure. To include ZEN conjugates in routine analysis, reliable standards are needed, which are currently not available. Thus, the aim of the present study was to develop a facilitated biosynthesis of ZEN-14-sulfate, ZEN-14-glucoside and ZEN-16-glucoside. A metabolite screening was conducted by adding ZEN to liquid fungi cultures of known ZEN conjugating Aspergillus and Rhizopus strains. Cultivation conditions and ZEN incubation time were varied. All media samples were analyzed for metabolite formation by HPLC-MS/MS. In addition, a consecutive biosynthesis was developed by using Fusarium graminearum for ZEN biosynthesis with subsequent conjugation of the toxin by utilizing Aspergillus and Rhizopus species. ZEN-14-sulfate (yield: 49%) is exclusively formed by Aspergillus oryzae. ZEN-14-glucoside (yield: 67%) and ZEN-16-glucoside (yield: 39%) are formed by Rhizopus oryzae and Rhizopus oligosporus, respectively. Purities of ≥73% ZEN-14-sulfate, ≥82% ZEN-14-glucoside and ≥50% ZEN-16-glucoside were obtained by 1H-NMR. In total, under optimized cultivation conditions, fungi can be easily utilized for a targeted and regioselective synthesis of ZEN conjugates. KW - Mycotoxin KW - Zearalenone KW - Conjugate KW - Biosynthesis KW - Fusarium KW - Aspergillus KW - Rhizopus PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-444246 DO - https://doi.org/10.3390/toxins10030104 SN - 2072-6651 VL - 10 IS - 3 SP - Article 104, 1 EP - 15 PB - MDPI CY - Basel AN - OPUS4-44424 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Roesch, Philipp A1 - Wittwer, Philipp A1 - Piechotta, Christian A1 - Lisec, Jan A1 - Sommerfeld, Thomas A1 - Kluge, Stephanie A1 - Herzel, Hannes A1 - Huthwelker, T. A1 - Borca, C. A1 - Simon, Franz-Georg T1 - Levels of per- and polyfluoroalkyl substances (PFAS) in various wastewater-derived fertilizers - Analytical investigations from different perspectives N2 - Solid wastewater-based fertilizers were screened for per- and polyfluoroalkyl substances (PFAS) by the extractable organic fluorine (EOF) sum parameter method. The EOF values for ten sewage sludges from Germany and Switzerland range from 154 to 7209 mg kg−1. For thermal treated sewage sludge and struvite the EOF were lower with values up to 121 mg kg−1. Moreover, the application of PFAS targeted and suspect screening analysis of selected sewage sludge samples showed that only a small part of the EOF sum parameter values can be explained by the usually screened legacy PFAS. The hitherto unknown part of EOF sum parameter contains also fluorinated pesticides, pharmaceutical and aromatic compounds. Because these partly fluorinated compounds can degrade to (ultra-)short PFAS in wastewater treatment plants they should be considered as significant sources of organic fluorine in the environment. The combined results of sum parameter analysis and suspect screening reveal the need to update current regulations, such as the German fertilizer ordinance, to focus not solely on a few selected PFAS such as perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) but consider an additional sum parameter approach as a more holistic alternative. Moreover, diffusion gradient in thin-films (DGT) passive samplers were utilized as an alternative simplified extraction method for PFAS in solid wastewater-based fertilizers and subsequently quantified via combustion ion chromatography. However, the DGT method was less sensitive and only comparable to the EOF values of the fertilizers in samples with >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 - 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 µg/kg, because of different diffusion properties for various PFAS, but also kinetic exchange limitations. However, the DGT approach has the advantage that almost no sample preparation is necessary. Moreover, the PFAS adsorption on the DGT binding layer was investigated via surface sensitive spectroscopical methods, such as Fourier-transform infrared (FT-IR) and fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy. T2 - DGT Konferenz CY - Paris, France DA - 11.10.2023 KW - Combustion Ion Chromatography KW - Per- and Polyfluoroalkyl substances (PFAS) KW - Sewage sludge PY - 2023 AN - OPUS4-58575 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Scholz, Philipp A1 - Jung, Christian A1 - Weidner, Steffen T1 - Thermo-Desorption Gas Chromatography-Mass Spectrometry for investigating the thermal degradation of polyurethanes N2 - Thermo-Desorption Gas Chromatography-Mass Spectrometry (TD-GC-MS) was used to investigate the thermal degradation of two different polyurethanes (PU). PU samples were heated at different heating rates and the desorbed products were collected in a cold injection system and thereafter submitted to GC-MS. Prospects and limitations of the detection and quantification of semi-volatile degradation products were investigated. A temperature dependent PU depolymerization was found at temperatures above 200 °C proved by an increasing release of 1,4-butanediol and methylene diphenyl diisocyanate (MDI) representing the main building blocks of both polymers. Their release was monitored quantitatively based on external calibration with authentic compounds. Size Exclusion Chromatography (SEC) of the residues obtained after thermodesorption confirmed the initial competitive degradation mechanism indicating an equilibrium of crosslinking and depolymerization as previously suggested. Matrix-Assisted Laser Desorption Ionization (MALDI) mass spectrometry of SEC fractions of thermally degraded PUs provided additional hints on degradation mechanism. KW - Thermo-desorption KW - Mass spectrometry KW - Polyurethanes KW - Thermal degradation PY - 2023 DO - https://doi.org/10.1039/D3AY00173C SN - 1759-9660 SP - 1 EP - 6 PB - Royal Society for Chemistry AN - OPUS4-57307 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -