TY - CONF A1 - Becker, Roland T1 - Zinc-dithialkyldithiophosphates in engine oils - Determination of Conent, Composition and Degradation during Operation using Gas and Liquid Chromatography T2 - 11th International Colloquium Tribology, Industrial and Automotive Lubrication CY - Esslingen am Neckar, Germany DA - 1998-01-13 PY - 1998 AN - OPUS4-5683 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schultze, Karin A1 - Nehls, Irene A1 - Bremser, Wolfram A1 - Becker, Roland A1 - Win, Tin T1 - Zertifiziertes Referenzmaterial "BAM-U007" - Organochlorpestizide in Boden T2 - ANAKON 2001 CY - Konstanz, Germany DA - 2001-04-04 PY - 2001 SP - 1(?) AN - OPUS4-1314 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dorgerloh, Ute A1 - Becker, Roland A1 - Nehls, Irene T1 - Volatile hydrocarbons in contaminated soil: Robustness of fractional quantification using headspace gas chromatography-mass-spectrometry N2 - Fuel contamination of soils display complex and variable hydrocarbon mixtures with different volatility and toxicity characteristics. A recently suggested headspace procedure for the structure-based quantification of volatile hydrocarbons is evaluated regarding repeatability, reproducibility, and practical robustness. Three aliphatic and three aromatic fractions covering the boiling range between 69 and 216°C were defined as summation parameters by their respective equivalent carbon number ranges. A standard mixture of 35 aliphatic and aromatic hydrocarbons was used for calibration on basis of selected mass fragments specific for the aliphatics and aromatics, respectively. Two standard soils were fortified with the standard mixture or different fuels, respectively, and submitted to the analytical procedure. Limit of detection (LOD) and limit of quantification (LOQ) were for all fractions lower than 0.1 and 0.3 mg/kg, respectively. Analyte recovery was linear up to between 20 and 110 mg hydrocarbons/kg soil depending on the fraction. Hydrocarbon recovery ranged between 80% and 110% depending on the fraction and the repeatability was typically better than 10%. Finally, the impact of extraction solvent variation, column solid-phase polarity, and alternative summation of fractions were investigated. The procedure was applied to liner samples taken from a site contaminated with aviation fuel and its practicability is discussed. KW - Gasoline KW - Contaminated site KW - Equivalent carbon number KW - Fuel KW - Static headspace PY - 2018 U6 - https://doi.org/10.1080/15320383.2018.1418287 SN - 1532-0383 SN - 1549-7887 VL - 27 IS - 1 SP - 1 EP - 12 PB - Taylor & Francis AN - OPUS4-43889 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bachmann, H. J. A1 - Bucheli, T. D. A1 - Dieguez-Alonso, A. A1 - Fabbri, D. A1 - Knicker, H. A1 - Schmidt, H.-P. A1 - Ulbricht, A. A1 - Becker, Roland A1 - Buscaroli, A. A1 - Buerge, D. A1 - Cross, A. A1 - Dickinson, D. A1 - Enders, A. A1 - Esteves, V.I. A1 - Evangelou, M. W. H. A1 - Fellet, G. A1 - Friedrich, K. A1 - Gasco Guerrero, G. A1 - Glaser, B. A1 - Hanke, U. M. A1 - Hanley, K. A1 - Hilber, I. A1 - Kalderis, D. A1 - Leifeld, J. A1 - Masek, O. A1 - Mumme, J. A1 - Paneque Carmona, M. A1 - Calvelo Pereira, R. A1 - Rees, F. A1 - Rombola, A. G. A1 - de la Rosa, J. M. A1 - Sakrabani, R. A1 - Sohi, S. A1 - Soja, G. A1 - Valagussa, M. A1 - Verheijen, F. A1 - Zehetner, F. T1 - Towards the standardization of biochar analysis: the COST action TD1107 interlaboratory comparison N2 - Biochar produced by pyrolysis of organic residues is increasingly used for soil amendment and many other applications. However, analytical methods for its physical and chemical characterization are yet far from being specifically adapted, optimized, and standardized. Therefore, COST Action TD1107 conducted an interlaboratory comparison in which 22 laboratories from 12 countries analyzed three different types of biochar for 38 physical–chemical parameters (macro- and microelements, heavy metals, polycyclic aromatic hydrocarbons, pH, electrical conductivity, and specific surface area) with their preferential methods. The data were evaluated in detail using professional interlaboratory testing software. Whereas intralaboratory repeatability was generally good or at least acceptable, interlaboratory reproducibility was mostly not (20% < mean reproducibility standard deviation < 460%). This paper contributes to better comparability of biochar data published already and provides recommendations to improve and harmonize specific methods for biochar analysis in the future. KW - Biochar KW - Analysis KW - Standardization KW - Ring test KW - Interlaboratory comparison PY - 2016 U6 - https://doi.org/10.1021/acs.jafc.5b05055 SN - 0021-8561 SN - 1520-5118 VL - 64 IS - 2 SP - 513 EP - 527 PB - American Chemical Society CY - Columbus, Ohio AN - OPUS4-35289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Esslinger, Susanne A1 - Becker, Roland A1 - Jung, Christian A1 - Schröter-Kermani, C. A1 - Nehls, Irene T1 - Time courses of HBCD levels and enantiomeric signatures in herring gull eggs from the German coast T2 - Dioxin 2010 - 30th International symposium on halogenated persistent organic pollutants CY - San Antonio, TX, USA DA - 2010-09-12 PY - 2010 UR - http://www.dioxin20xx.org/pdfs/2010/10-1112.pdf N1 - Serientitel: Organohalogen Compounds – Series title: Organohalogen Compounds VL - 72 SP - 255 EP - 258 AN - OPUS4-23167 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Esslinger, Susanne A1 - Jung, Christian A1 - Schröter-Kermani, C. A1 - Nehls, Irene T1 - Time courses of HBCD levels and enantiomeric signatures in herring gull eggs from the German coast T2 - 30 th International Symposium on Halogenated Persistent Organic Pollutants (Dioxin 2010) CY - San Antonio, TX, USA DA - 2010-09-12 PY - 2010 AN - OPUS4-21600 LA - deu 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 U6 - 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 - TY - CONF A1 - Becker, Roland A1 - Koch, Matthias A1 - Lehnik-Habrink, Petra A1 - Buge, Hans-Gerhard T1 - The role of matrix reference materials in the process of method validation - A case study: PCBs in cable coverings T2 - BERM 9 - 9th International Symposium on Biological and Environmental Reference Materials CY - Berlin, Germany DA - 2003-06-15 PY - 2003 AN - OPUS4-4793 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dorgerloh, Ute A1 - Becker, Roland A1 - Theißen, H. A1 - Nehls, Irene T1 - The quantification of hydrogen and methane in contaminated groundwater: validation of robust procedures for sampling and quantification N2 - A number of currently recommended sampling techniques for the determination of hydrogen in contaminated groundwater were compared regarding the practical proficiency in field campaigns. Key characteristics of appropriate sampling procedures are reproducibility of results, robustness against varying field conditions such as hydrostatic pressure, aquifer flow, and biological activity. Laboratory set-ups were used to investigate the most promising techniques. Bubble stripping with gas sampling bulbs yielded reproducible recovery of hydrogen and methane which could be verified for groundwater sampled in two field campaigns. The methane content of the groundwater was confirmed by analysis of directly pumped samples thus supporting the trueness of the stripping results. Laboratory set-ups and field campaigns revealed that bubble stripping of hydrogen may be restricted to the type of used pump. Concentrations of dissolved hydrogen after bubble stripping with an electrically driven submersible pump were about one order of magnitude higher than those obtained from diffusion sampling. The gas chromatographic determination for hydrogen and methane requires manual injection of gas samples and detection by a pulsed discharge detector (PDD) and allows limits of quantification of 3 nM dissolved hydrogen and 1 µg L-1 dissolved methane in groundwater. The combined standard uncertainty of the bubble stripping and GC/PDD quantification of hydrogen in field samples was 7% at 7.8 nM and 18% for 78 nM. PY - 2010 U6 - https://doi.org/10.1039/c0em00091d SN - 1464-0325 SN - 1464-0333 VL - 12 IS - 10 SP - 1876 EP - 1884 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-22176 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Buge, Hans-Gerhard A1 - Becker, Roland A1 - Nehls, Irene T1 - The preparation and characterization of solid matrix reference materials for the trace analysis of organic environmental pollutants - relevant aspects of quality management N2 - Feste Referenzmaterialien für die Spurenanalytik umweltrelevanter organischer Schadstoffe erfordern aufgrund der geringen thermischen Belastbarkeit der Analyten besondere Aufarbeitungsstrategien für die Herstellung repräsentativer Teilproben. Das in der Fachgruppe I.2 seit 1994 für diesen Zweck systematisch aufgebaute technologische Instrumentarium wird vorgestellt, und das im Laufe der Jahre angesammelte Know How wird anhand von Beispielen vermittelt. Das im Laboratorium I.21 entwickelte Qualitätssystem für eine optimale Logistik der Arbeitsabläufe der Probenherstellung und -verwaltung sowie für eine bedarfsgerechte Charakterisierung der Materialien wird ausführlich erläutert. Bezüglich der Verwendung der Referenzmaterialien wird herausgestellt, daß es zwei gleichberechtigte Anwendungsrichtungen gibt: die interne Qualitätskontrolle mit zertifizierten Referenzmaterialien (ZRM, z.B. für die Methodenvalidierung) und die externe Qualitätskontrolle (Proficiency Testing = Kompetenzbewertung von Prüflaboratorien). Referenzmaterialien für das Proficiency Testing, die im Umweltbereich in viel größeren Stückzahlen umgesetzt werden können als ZRM, weisen bezüglich Homogenität und Charakterisierung die gleichen Qualitätskriterien wie ZRM auf. Diese Materialien haben - auch im internationalen Maßstab - stark an Bedeutung gewonnen. Ein englisches Abstract gibt es nicht, aber eine Grobgliederung zur Vortragsankündigung: This lecture includes: · the technological and logistical aspects of reference material preparation and sub-sampling and subsequent sample management, · appropriate measurement strategies for homogeneity and stability studies, · the use of relevant statistical tests to evaluate those measurement data, · the organisation of interlaboratory studies based on traceable measurements T2 - CENAM CY - Querétaro, Mexico DA - 2002-03-01 PY - 2002 AN - OPUS4-1612 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mönch, Bettina A1 - Becker, Roland A1 - Jung, Christian A1 - Nehls, Irene T1 - The homogeneity testing of EtG in hair reference materials: A high-throughput procedure using GC-NCI-MS N2 - The validation of a robust quantification procedure for EtG in hair using GC–NCI–MS is presented. Aqueous extraction is followed by complete lyophylization of the extract and derivatization with pentafluoropropionic anhydride (PFPA) under controlled temperature and duration. Clean-up of extracts was dispensable and standard single quadrupole MS displayed sufficient selectivity and sensitivity. The method displayed a wide linearity range and enabled LOD of 0.68 pg/mg, LOQ of 2.4 pg/mg, and precision below 8.12%. Since EtG was seen to display prolonged stability in the aqueous extracts and after derivatization with PFPA this straightforward procedure allows a routine throughput of large quantities of samples with little proneness to procedural scatter of results. The method was applied to demonstrate the homogeneity of two hair reference materials with mean EtG contents of 8.48 pg/mg and 22.0 pg/mg. Aside from the application in homogeneity studies of hair reference materials predominantly in the concentration range of 10–50 pg/mg the method was also designed for daily routine quantification of real-world sample with regard to drinking behavior assessment. KW - Extraction KW - Derivatization KW - High-throughput analysis KW - Reference materials KW - Homogeneity KW - Measurement uncertainty PY - 2013 U6 - https://doi.org/10.1016/j.forsciint.2013.01.018 SN - 0379-0738 SN - 1872-6283 VL - 226 IS - 1-3 SP - 202 EP - 207 PB - Elsevier Ltd. CY - Amsterdam [u.a.] AN - OPUS4-27998 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mueller, Axel A1 - Becker, Roland A1 - Dorgerloh, Ute A1 - Simon, Franz-Georg A1 - Braun, Ulrike T1 - The effect of polymer aging on the uptake of fuel aromatics and ethers by microplastics N2 - Microplastics are increasingly entering marine, limnic and terrestrial ecosystems worldwide, where they sorb hydrophobic organic contaminants. Here, the sorption behavior of the fuel-related water contaminants benzene, toluene, ethyl benzene and xylene (BTEX) and four tertiary butyl ethers to virgin and via UV radiation aged polypropylene (PP) and polystyrene (PS) pellets was investigated. Changes in material properties due to aging were recorded using appropriate polymer characterization methods, such as differential scanning calorimetry, Fourier transform infrared spectroscopy, gel permeation chromatography, X-ray photoelectron spectroscopy, and microscopy. Pellets were exposed to water containing BTEX and the ethers at 130-190 mg/L for up to two weeks. Aqueous sorbate concentrations were determined by headspace gas chromatography. Sorption to the polymers was correlated with the sorbate's Kow and was significant for BTEX and marginal for the ethers. Due to substantially lower glass transition temperatures, PP showed higher sorption than PS. Aging had no effect on the sorption behavior of PP. PS sorbed less BTEX after aging due to an oxidized surface layer. KW - BTEX KW - Polypropylene KW - Polystyrene KW - Sorption KW - Degradation PY - 2018 U6 - https://doi.org/10.1016/j.envpol.2018.04.127 SN - 0269-7491 VL - 240 SP - 639 EP - 646 PB - Elsevier CY - Amsterdam AN - OPUS4-44990 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Sporkert, F. A1 - Lô, I. A1 - Baumgartner, M. T1 - The determination of ethyl glucuronide in hair: Experiences from nine consecutive interlaboratory comparison rounds N2 - The increasing request for hair ethyl glucuronide (HEtG) in alcohol consumption monitoring according to cut-off levels set by the Society of Hair Testing (SoHT) has triggered a proficiency testing program based on interlaboratory comparisons (ILC). Here, the outcome of nine consecutive ILC rounds organised by the SoHT on the determination of HEtG between 2011 and 2017 is summarised regarding interlaboratory reproducibility and the influence of procedural variants. Test samples prepared from cut hair (1 mm) with authentic (in-vivo incorporated) and soaked (in-vitro incorporated) HEtG concentrations up to 80 pg/mg were provided for 27–35 participating laboratories. Laboratory results were evaluated according to ISO 5725-5 and provided robust averages and relative reproducibility standard deviations typically between 20 and 35% in reasonable accordance with the prediction of the Horwitz model. Evaluation of results regarding the analytical techniques revealed no significant differences between gas and liquid chromatographic methods In contrast, a detailed evaluation of different sample preparations revealed significantly higher average values in case when pulverised hair is tested compared to cut hair. This observation was reinforced over the different ILC rounds and can be attributed to the increased acceptance and routine of hair pulverisation among laboratories. Further, the reproducibility standard deviations among laboratories performing pulverisation were on average in very good agreement with the prediction of the Horwitz model. Use of sonication showed no effect on the HEtG extraction yield. KW - Ethyl glucuronide KW - Interlaboratory comparison KW - Proficiency testing KW - Society of hair testing KW - Reproducibility KW - Pulverization PY - 2018 U6 - https://doi.org/10.1016/j.forsciint.2018.04.025 SN - 0379-0738 SN - 1872-6283 VL - 288 SP - 67 EP - 71 PB - Elsevier AN - OPUS4-44881 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Buge, Hans-Gerhard A1 - Nehls, Irene T1 - The determination of adsorbable organically bound halogens (AOX) in soil: interlaboratory comparisons and reference materials N2 - The interlaboratory variability in the quantification of adsorbable organically bound halogens (AOX) in industrially contaminated soil is presented. Three consecutive rounds of a proficiency testing scheme, in which between 88 and 119 routine laboratories participated, yielded relative reproducibility standard deviations between 7 and 20% at AOX contents between 10.9 and 268 mg kg-1. Nineteen laboratories with established proficiency were invited to participate in the certification of the AOX content in three soil reference materials meant for the internal quality control in analytical laboratories. The certified values are (1349 ± 59) mg kg-1, (80 ± 7) mg kg-1 and (102 ± 8) mg kg-1, respectively. KW - Certified reference materials KW - European Reference Material KW - Proficiency testing KW - Organohalogen compounds KW - Summation parameter PY - 2007 U6 - https://doi.org/10.1007/s00769-007-0308-z SN - 0949-1775 SN - 1432-0517 VL - 12 IS - 12 SP - 647 EP - 651 PB - Springer CY - Berlin AN - OPUS4-16670 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Esslinger, Susanne A1 - Becker, Roland A1 - Jung, Christian A1 - Schröter-Kermani, C. A1 - Bremser, Wolfram A1 - Nehls, Irene T1 - Temporal trend (1988-2008) of hexabromocyclododecane enantiomers in herring gull eggs from the german coastal region N2 - Levels of α-, β-, and γ-hexabromocyclododecane (HBCD) were determined in pooled eggs from herring gulls (Larus argentatus) sampled on three bird sanctuaries near the German North Sea coast between 1988 and 2008 (Mellum and Trischen) and the German Baltic Sea coast between 1998 and 2008 (Heuwiese) and archived by the German Environmental Specimen Bank. Pressurized fluid extraction, gel permeation chromatography, and LC–MS/MS using 13C12-labelled isotope standards and a chiral column were applied. α-HBCD was the dominating diastereomer and ranged between 3.7 and 107 ng g-1 lw while β- and γ-HBCD were throughout close to LOQ. The highest α-HBCD concentration was found in eggs from Mellum sampled in the year 2000. Interestingly, HBCD in eggs from the three islands displayed similar time courses with levels increasing to a peak contamination around 2000 and decreasing levels ever since. Chiral signatures of α-HBCD in eggs differed among the islands but indicated a preferential enrichment of the first eluting enantiomer (-)-α-HBCD. KW - Brominated flame retardant KW - Chiral separation KW - HPLC-ESI-MS/MS KW - Enantiomer-specific bioaccumulation PY - 2011 U6 - https://doi.org/10.1016/j.chemosphere.2010.12.047 SN - 0045-6535 SN - 0366-7111 VL - 83 IS - 2 SP - 161 EP - 167 PB - Elsevier Science CY - Kidlington, Oxford AN - OPUS4-23351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ogrinc, N. A1 - Rossi, A. M. A1 - Durbiano, F. A1 - Becker, Roland A1 - Milavec, M. A1 - Bogozalec Kosir, A. A1 - Kakoulides, E. A1 - Ozer, H. A1 - Akcadag, F. A1 - Goenaga-Infante, H. A1 - Quaglia, M. A1 - Mallia, S. A1 - Umbricht, G. A1 - O'Connor, G. A1 - Guettler, B. T1 - Support for a European metrology network on food safety Food-MetNet N2 - This paper describes Food-MetNet, a coordinated preparatory initiative to establish the European Metrology Network on Food Safety (EMN-FS). Food-MetNet aims to establish a long-term ongoing dialogue between the metrology community and relevant stakeholders, in particular, European Union Reference Laboratories (EURLs), National Reference Laboratories (NRLs) and the Joint Research Centre (JRC). This dialogue is meant to support the collection of needs from stakeholders, the take-up of metrological research output and the development of the roadmaps needed to navigate future research. KW - Network KW - Metrology KW - Food KW - Safety KW - Stakeholders PY - 2021 U6 - https://doi.org/10.1016/j.measen.2021.100285 VL - 18 SP - 1 EP - 4 PB - Elsevier AN - OPUS4-53740 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bremser, Wolfram A1 - Becker, Roland A1 - Kipphardt, Heinrich A1 - Lehnik-Habrink, Petra A1 - Panne, Ulrich A1 - Töpfer, Antje T1 - Stability testing in an integrated scheme N2 - ISO Guide 35 deals with RM stability issues and scrutinizes the evaluation of stability testing results under the assumption that either there is no trend at all (a rather rare situation), or any observed deterministic change is insignificant and thus can be neglected. However, market demands for reliable reference materials are obviously not limited to stable or at least seemingly stable materials. In many analytical applications, analytes and measurands under consideration are known, or at least suspected, to be unstable on time scales that may vary widely from measurand to measurand. The Federal Institute for Materials Research and Testing (BAM) has developed (and successfully uses) an integrated approach in its certification practice. The approach is based on an initial stability study and subsequent post-certification monitoring. Data evaluation is model-based and takes advantage of all information collected in the stability testing scheme(s). It thus allows one to deal with any kind of instability observed, to assess limiting time intervals at any stress condition in the range tested, to estimate a final expiry date for materials with detected instabilities or the maximum admissible re-testing interval for seemingly stable materials, and to assess maximum admissible stress loads during delivery of the material to the customer. The article describes (and exemplifies) typical study layout, the model selection, and the integrated data assessment. KW - Certified reference materials KW - Stability KW - Shelf life KW - Arrhenius model KW - ERM PY - 2006 U6 - https://doi.org/10.1007/s00769-006-0152-6 SN - 0949-1775 SN - 1432-0517 VL - 11 IS - 10 SP - 489 EP - 495 PB - Springer CY - Berlin AN - OPUS4-14063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ammann, Dominic A1 - Becker, Roland A1 - Nehls, Irene T1 - Stability of ethyl glucuronide in hair reference materials after accelerated aging N2 - Two different hair reference materials, one produced from authentic hair displaying an ethyl glucuronide (EtG) content of about 25 pg/mg and one obtained by fortification of blank hair to an EtG level of 85 pg/mg were submitted to accelerated aging between 4 degrees C and 60 degrees C for periods between one and 24 months. Subsequently, the EtG content was determined in the aged samples and untreated reference samples stored at -22 degrees C under repeatability conditions following the so-called isochronous approach. The EtG content remained stable even at 40 degrees C for 24 months and at 60 degrees C over six months. This is in contrast to many organic analytes contained in trace concentrations in diverse matrices. A slight but significant increase of the recovered EtG in case of authentic hair samples having been exposed for 24 months between 4 degrees C and 60 degrees C may be due to a temperature-driven process that allows increased recoveries of the physiologically embedded EtG. KW - Alcohol marker KW - Micropulverization KW - HPLC-MS/MS KW - Fortification KW - Long term stability PY - 2015 U6 - https://doi.org/10.1016/j.forsciint.2015.09.015 SN - 0379-0738 SN - 1872-6283 VL - 257 SP - 337 EP - 340 PB - Elsevier Ireland Ldt. CY - Amsterdam [u.a.] AN - OPUS4-34940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Dorgerloh, Ute A1 - Theißen, H. A1 - Nehls, Irene T1 - Stabilisation of groundwater samples for the quantification of organic trace pollutants N2 - The concentration of contaminants in groundwater samples can be decreased by degradation in the time course between field sampling and quantification in the laboratory, especially in samples from sites where degradation activity is enhanced by remediation measures. The sampling sites covered a variety of priority organic pollutants such as volatile aromatic and chlorinated compounds, phenols and petroleum hydrocarbons and different remediation strategies such as anaerobic and aerobic microbial in situ degradation, in situ chemical oxidation, and on-site purification with biological treatment. The stability of the contaminants' concentration was investigated over a time range of several hours without cooling in the autosampler of the analytical equipment (short term) and over several days of storage until analysis (long term). A number of stabilisation techniques suggested in international standards ISO 5667-3:2013 and ASTM D6517:2000 were compared both with regard to short term and long term stabilisation of the contaminants and their practicability for field sampling campaigns. Long term storage turned out to be problematic for most compound groups even under cooling. Short term stability was problematic also for volatiles such as benzenic aromates, naphthalene and volatile organic halogenated compounds to be analysed by headspace gas chromatography. Acidification (pH <2) was sufficient to prevent degradation of benzenic aromates, naphthalene, phenols and petrol hydrocarbons for up to seven days. The use of acids was not applicable to stabilise volatiles in waters rich in carbonates and sulphides due to stripping of the volatiles with the liberated gases. The addition of sodium azide was successfully used for stabilisation of volatile organic halogenated compounds. KW - Groundwater KW - Sampling KW - Organic pollutants KW - Stabilisation KW - Analysis PY - 2013 U6 - https://doi.org/10.1039/c3em00332a SN - 2050-7887 SN - 2050-7895 VL - 15 IS - 12 SP - 2329 EP - 2337 PB - RSC Publ. CY - CambridgeRSC Publ. AN - OPUS4-29689 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Dorgerloh, Ute A1 - Helmis, Mario A1 - Paulke, E. A1 - Mumme, J. A1 - Nehls, Irene T1 - Solid and liquid products of hydrothermal carbonizsation: Patterns of volatile organic compounds T2 - Third International Symposium on Green Chemistry for Environment, Health and Development CY - Skiathos, Greece DA - 2012-10-03 PY - 2012 AN - OPUS4-26632 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Buge, Hans-Gerhard A1 - Scharf, Holger A1 - Becker, Roland ED - Gills, T. T1 - Soil samples prepared for a proficiency testing scheme operated by BAM T2 - 8th International Symposium on Biological and Environmental Reference Materials ; 8th BERM CY - Bethesda, MD, USA DA - 2000-09-17 PY - 2001 SN - 1618-2642 VL - 370 IS - 2-3 SP - 174 PB - Springer CY - Berlin AN - OPUS4-944 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland T1 - Soil proficiency testing at BAM T2 - Seminario Sectorial Ambiente 2002, Centro National de Metrologia (CENAM) CY - Querétaro, Mexico DA - 2002-09-13 PY - 2002 AN - OPUS4-5833 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scharf, Holger A1 - Becker, Roland A1 - Buge, Hans-Gerhard T1 - Soil Analysis - The BAM Proficiency Testing Scheme "Contaminated Sites" T2 - International ILAC/IAF Conference on Accreditation in Global Trade CY - Berlin, Germany DA - 2002-09-23 KW - Böden KW - Eignungsprüfung KW - Qualitätssicherung KW - Ringversuche KW - Umweltanalytik PY - 2002 AN - OPUS4-2361 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Becker, Roland A1 - Kalbe, Ute A1 - Sauer, Andreas ED - Moser, H. ED - Römbke, J. T1 - Selection and characterization of test samples and eluates KW - Municipial waste incineration ash KW - Gaswork contaminated soil KW - Copper-contaminated wood KW - Bulk material KW - Eluates KW - Ökotoxikologie KW - Biotests KW - Abfall KW - Europäische Normung (CEN) KW - Ringversuch PY - 2009 SN - 978-0-387-88958-0 U6 - https://doi.org/10.1007/978-0-387-88959-7 N1 - Geburtsname von Sauer, Andreas: Buchholz, A. - Birth name of Sauer, Andreas: Buchholz, A. SP - 35 EP - 46 PB - Springer Science + Business Media AN - OPUS4-22944 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Sauer, Andreas A1 - Kalbe, Ute T1 - Sample preparation and analytical results T2 - Internationaler CEN/DIN-Workshop im Rahmen des Vh 1287 (Ökotox-Ringversuch), PTB, DIN CY - Berlin, Germany DA - 2007-06-29 PY - 2007 N1 - Geburtsname von Sauer, Andreas: Buchholz, A. - Birth name of Sauer, Andreas: Buchholz, A. AN - OPUS4-16130 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dorgerloh, Ute A1 - Becker, Roland A1 - Nehls, Irene T1 - Ringversuche: Präparation mineralölkohlenwasserstoffhaltiger Abwasserproben KW - Analytik KW - Ringversuch KW - Abwasser KW - Mineralölkohlenwasserstoff KW - Probe KW - Qualitätssicherung KW - Chemical analysis KW - Interlaboratory comparison KW - Wastewater KW - Mineral oil KW - Sample KW - Quality assurance PY - 2008 SN - 0083-6915 VL - 106 IS - 3 SP - 7 EP - 8 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-18289 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Luther, W. T1 - Ringversuch: Methodenvergleich zur Bestimmung von PAK im Boden T2 - 2. Anwendertreffen über kritische Fluide; Universität Siegen CY - Siegen, Germany DA - 1997-10-08 PY - 1997 AN - OPUS4-5674 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Nehls, Irene A1 - Buge, Hans-Gerhard T1 - Referenzmaterialien für Umweltanalysen PY - 2001 SN - 0016-3538 IS - 45 SP - 1089 EP - 1091 PB - GIT-Verlag CY - Darmstadt AN - OPUS4-1186 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Nehls, Irene A1 - Buge, Hans-Gerhard T1 - Referenzmaterialien für die organisch-chemische Umweltanalytik T2 - Vortrag der Fachhochschule Lausitz CY - Senftenberg, Germany DA - 2003-12-09 PY - 2003 AN - OPUS4-5860 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Altmann, Korinna A1 - Braun, Ulrike T1 - Reference materials for microplastics in environmental matrices N2 - The pollution of marine, limnic and terrestrial environments with plastic waste and the potential impact especially on biota and humans has received increasing attention in recent years. Special focus is on particles smaller than 5 mm, the so-called microplastics. Consequently, possible regulations of emission and remediation efforts require sound information on the occurrence and fate of microplastics in the respective environmental compartments. Microplastics (MP) differ from classical organic pollutants in biota or the environment in that they do not consist of clearly defined low-molecular weight compounds but of polymer particulates with varying sizes and chemical compositions. This leads to specific challenges regarding the analytical techniques to be employed for their identification and quantification. Microplastics are defined as polymer particle in the size range between 1 µm and 5 mm and cover a wide range of polymers such as polyethylene, polypropylene, polystyrene and polyethylene terephthalate in variable geometric shapes. Properties relevant for environmental microplastics are polymer type, particle form and size distribution, surface morphology (aging status) and total mass fraction contained in a given sample. Polymer identification and particle size estimation using optical methods (IR and Raman spectroscopy) are time consuming and complicated by surface characteristics as a result of weathering, soiling, and microbial colonisation. Total mass fractions of MP in environmental samples can be determined by thermo-analytical methods. There are currently no standardised methods for sampling, sampling preparation, or detection of MP in environmental samples. So far, qualitative and quantitative investigations are done by research institutes and have not reached the routine laboratory community. The near future will see harmonisation efforts of MP mass fraction determination in environmental matrices by thermo-analytical procedures. The immediate need for reference materials during method development and comparison is outlined with regard to relevant matrix/polymer compositions, existing regulations and currently achievable detection limits. Examples for solid environmental matrix reference materials are discussed regarding the challenges encountered with matrices and polymer types as well as homogeneity testing and property value characterisation. T2 - BERM 2018 15th International Symposium on Biological and Environmental Reference Materials CY - Berlin, Germany DA - 23 September 2018 KW - Referenzmaterialien KW - Schwebstoffe KW - Sediment KW - Polymer PY - 2018 AN - OPUS4-46209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Altmann, Korinna A1 - Braun, Ulrike T1 - Querschnittsthema Referenzmaterialien: Planung Ringversuche N2 - Nach einer Erläuterung der international üblichen Definitionen von Referenzmaterialien und Matrix-Referenzmaterialien erfolgt eine Zusammenfassung der spezifischen Anforderungen bei Herstellung und Charakterisierung. Weiterhin werden die unterschiedlichen Anforderungen an die Durchführung von Ringversuchen im Sinne eines Methodenvergleiches, einer Eignungsprüfung von Laboratorien und der Zertifizierung von Matrix-Referenzmaterialien gegenübergestellt. Für den aktuell geplanten ersten Ringversuch zur Quantifizierung von Mikroplastik in Schwebstoffen mittels thermischer Verfahren werden die konkreten technischen Bedingungen zur Herstellung entsprechender Referenzmaterialien einschließlich der Homogenitätsprüfung ihrer Mikroplastikgehalte dargestellt. Die Besonderheiten des Ringversuches vor dem Hintergrund einer Normung der eingesetzten Verfahren werden diskutiert. T2 - Forschungsschwerpunkt „Plastik in der Umwelt – Quellen • Senken • Lösungsansätze“: 2. Workshop des Querschnittsthemas „Analytik und Referenzmaterialien“ CY - Augsburg, Germany DA - 4.7.2018 KW - Mikroplastik KW - Referenzmaterialien KW - Ringversuche KW - Thermische Verfahren KW - Schwebstoffe KW - Methodenvergleich PY - 2018 AN - OPUS4-45681 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Koch, Matthias A1 - Wachholz, Sigrid A1 - Win, Tin T1 - Quantification of total petrol hydrocarbons (TPH) in soil by IR-spectrometry and gas chromatography - conclusions from three proficiency testing rounds N2 - Due to the utilisation of 1,1,2-trichlorotrifluoroethane (CFE) as extraction solvent the IR-spectrometric determination of total petrol hydrocarbon (TPH) in soil according to ISO/TR 11046 has been replaced by gas chromatography/flame ionisation detection (GC/FID) after extraction with a halogen-free solvent according to ISO/DIS 16703:2001. The results obtained with both methods by field laboratories in three proficiency testing (PT) rounds are compared. The consensus means obtained with GC/FID are typically 10%-20% (ranging between 0% and 25%) higher than those found with IR-spectroscopy. On the contrary, coefficients of variation (CV) are roughly double in case of GC/FID and are briefly discussed against the background of the Horwitz equation. KW - Hydrocarbons KW - Soil KW - IR spectrometry KW - Gas chromatography KW - Interlaboratory comparison PY - 2002 U6 - https://doi.org/10.1007/s00769-002-0476-9 SN - 0949-1775 SN - 1432-0517 VL - 7 IS - 7 SP - 286 EP - 289 PB - Springer CY - Berlin AN - OPUS4-1627 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Koch, Matthias A1 - Lehnik-Habrink, Petra A1 - Nehls, Irene T1 - Quantification of polychlorinated biphenyls in plastic granulates from the recycling of cables - Reference materials and interlaboratory comparison N2 - A procedure for the quantification of the PCB marker congeners 28, 52, 101, 138, 153, 180 in plastic waste form the recycling of cables in the range of content between 0.1 mg kg-1 and 20 mg kg-1 was validated. Representative reference materials for laboratory analyses were produced using granulates from different recycling processes. The method development included aspects of grinding, sieving, homogenising as well as the comparison of extraction methods and chromatographic conditions. The validated procedure foresees grinding of the technical sample to an upper particle size limit of 0.50 mm followed by extraction with an unpolar solvent such as n-hexane and gas chromatographic determination. LOD and LOQ for individual congeners ranged between 0.01 mg kg-1 and 0.08 mg kg-1. Electron capture detection (ECD) and mass selective detection (MS) were equivalent if chromatographic conditions were appropriately selected. The application of MS was advantageous in presence of significant amounts of interfering components which have been found in some cables. Three reference materials containing the marker congeners in the range of 0.1 mg kg-1–5 mg kg-1 were submitted to a final validation intercomparison with 23 selected field laboratories using the developed method. Relative reproducibility standard deviations varied between 15% and 33%. KW - PCB KW - Waste KW - Analysis KW - Method validation KW - Standardisation PY - 2006 U6 - https://doi.org/10.1016/j.chemosphere.2006.02.035 SN - 0045-6535 SN - 0366-7111 VL - 65 IS - 9 SP - 1652 EP - 1659 PB - Elsevier Science CY - Kidlington, Oxford AN - OPUS4-14050 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Altmann, Korinna A1 - Sommerfeld, Thomas A1 - Braun, Ulrike T1 - Quantification of microplastics in a freshwater suspended organic matter using different thermoanalytical methods – outcome of an interlaboratory comparison N2 - A sedimented freshwater suspended organic matter fortified with particles of polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) was employed in an interlaboratory comparison of thermoanalytical methods for microplastics identification and quantification. Three laboratories performed pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), three others provided results using thermal extraction desorption followed by gas chromatography coupled to mass spectrometry (TED-GC-MS). One participant performed thermogravimetry-infrared spectroscopy (TGA-FTIR) and two participants used thermogravimetry coupled to mass spectrometry (TGA-MS). Further participants used differential scanning microscopy (DSC), a procedure based on micro combustion calorimetry (MCC) and a procedure based on elemental analysis. Each participant employed a different combination of sample treatment, calibration and instrumental Settings for polymer identification and quantification. Though there is obviously room for improvements regarding the between-laboratory reproducibility and the harmonization of procedures it was seen that the participants Performing Py-GC-MS, TED-GC-MS, and TGA-FTIR were able to correctly identify all polymers and to report reasonable quantification results in the investigated concentration range (PE: 20.0 μg/mg, PP: 5.70 μg/mg; PS: 2.20 μg/mg, PET: 18.0 μg/mg). Although for the other methods limitations exists regarding the detection of specific polymers, they showed potential as alternative approaches for polymer quantification in solid environmental matrices. KW - Interlaboratory comparison KW - Microplastics KW - Suspended organic matter KW - Pyrolysis PY - 2020 U6 - https://doi.org/10.1016/j.jaap.2020.104829 VL - 148 SP - 1 EP - 6 PB - Elsevier B.V. AN - OPUS4-50977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Mönch, Bettina A1 - Ammann, Dominic A1 - Nehls, Irene T1 - Quantification of ethyl glucuronide in hair: The effect of milling and sonication on the extraction efficiency T2 - 18th Meeting of the Society of Hair Testing CY - Geneva, Switzerland DA - 2013-08-28 PY - 2013 AN - OPUS4-28722 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mönch, Bettina A1 - Becker, Roland A1 - Nehls, Irene T1 - Quantification of ethyl glucuronide in hair: effect of milling on extraction efficiency N2 - Aim: The objective of the study was to provide conclusive evidence for the effect of particle size reduction as by milling on the extractable content of ethyl glucuronide (EtG) of hair samples. Methods: A number of real case hair samples and two pooled hair materials with EtG contents in the range of 10–30 pg/mg were systematically compared with regard to the extraction yield of EtG after cutting to 2–3 mm length and pulverization with a ball mill. After the respective treatment the samples were submitted to aqueous extraction followed by quantification of EtG using HPLC-MS/MS. Results: It was unequivocally demonstrated that milling of hair samples prior to aqueous extraction significantly increases the extractable EtG content compared with cut hair. The effect ranged between 137 and 230% and was seen to occur regardless of the extent of pulverization. Cooling of samples was not necessary to prevent partial degradation of EtG during the grinding procedure. Conclusion: The options currently employed at choice in analytical practice (cutting or milling) were seen to significantly affect the extractable amount of EtG in hair. This is suspected to influence the degree of equivalence of quantification results obtained in different laboratories as well as their respective classification of a test subject's drinking behaviour on the basis of currently recommended cut-off values. PY - 2013 U6 - https://doi.org/10.1093/alcalc/agt059 SN - 0735-0414 SN - 0309-1635 SN - 1464-3502 VL - 48 IS - 5 SP - 558 EP - 563 PB - Univ. Press CY - Oxford AN - OPUS4-28843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Dorgerloh, Ute A1 - Sauer, Andreas A1 - Hofmann, Andrea T1 - Quality control in extended measurement campaigns: selection of contract laboratories by proficiency testing exemplified for the trace analysis of anilines in groundwater N2 - An interlaboratory comparison for the determination of aniline, nine methylated anilines and chlorinated anilines in contaminated groundwater (each compound between 1 µg L-1 and 750 µg L-1) was conducted as proficiency test for the selection of contract laboratories for a groundwater monitoring campaign. For the 13 participants, two different test sample series were prepared from a stabilized real case groundwater. Series A was the groundwater as sampled in the field and series B was prepared from series A by spiking with selected anilines. Homogeneity and stability investigations revealed that contaminated groundwater provides a viable basis for the preparation of ring test samples for the determination of anilines. Analytical procedures were limited to the standardized liquid–liquid extraction or solid-phase extraction in combination with gas chromatography/mass spectrometry (DIN 38407-16:1999). The robust consensus values were evaluated according to the standardized protocol of DIN 38402-45:2013. Robust reproducibility standard deviations ranged largely between 20?% and 60?% depending on the analyte. The proficiency assessment of individual participants combined the qualitative aspect of correct peak identification with the quantitative determination of individual concentrations within set limits in a unified approach. It could be shown that the accreditation status of laboratory and the existence of a standardized analytical procedure do not substitute a problem-related proficiency assessment of potential contractors. KW - Aniline KW - Chloroanilines KW - Methylanilines KW - Groundwater KW - Interlaboratory comparison KW - Proficiency test PY - 2014 U6 - https://doi.org/10.1007/s00769-014-1072-5 SN - 0949-1775 SN - 1432-0517 N1 - Geburtsname von Sauer, Andreas: Buchholz, A. - Birth name of Sauer, Andreas: Buchholz, A. VL - 19 IS - 5 SP - 371 EP - 376 PB - Springer CY - Berlin AN - OPUS4-31756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland T1 - Proficiency testing of laboratories by interlaboratory comparisons T2 - Workshop of proficiency testing of laboratories by interlaboratory comparisons CY - Dar Es Salaam, Tanzania DA - 2005-07-06 PY - 2005 AN - OPUS4-7650 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Buge, Hans-Gerhard A1 - Nehls, Irene T1 - Proficiency testing of field laboratories - Experience from the soil sector T2 - Workshop on Laboratory Proficiency Testing (Umweltbundesamt) CY - Berlin, Germany DA - 2004-10-07 PY - 2004 AN - OPUS4-5465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dorgerloh, Ute A1 - Theissen, H. A1 - Becker, Roland A1 - Hilbert, S. A1 - Nehls, Irene T1 - Probennahme und Quantifizierung von LHKW, Ethen und Methan in Grundwasser N2 - Der Einsatz aktiver (Pumpprobennahme, Schöpfprobennahme) und passiver (Diffusionsprobennahme) Probennahmetechniken zur Gehaltsbestimmung von LHKW sowie Ethen und Methan in Grundwasser wird aus ordnungsbehördlicher Sicht hinsichtlich der Vergleichbarkeit von Analysendaten untersucht. Am Beispiel einer Kontamination mit Trichlorethen sowie 1,2-Dichlorethen und Vinylchlorid kann deutlich gemacht werden, dass die Einsatzmöglichkeit der passiven Probennahme durch unzureichende Strömungsverhältnisse im Aquifer sowie biologische Aktivität im Pegelrohr begrenzt ist. Der aktiven Probennahme ist bei ungeklärten oder unzureichenden Strömungsverhältnissen im Grundwasserleiter daher der Vorzug zu geben. Das gaschromatographische Verfahren für Vinylchlorid mittels Dampfraumtechnik wird um die Quantifizierung von Methan und Ethen erweitert. Dabei werden für die Bewertung von Altlasten relevante Bestimmungsgrenzen von 0,1 µg/l (Vinylchlorid, Ethen) sowie 5 µg/l (Methan) erreicht. Aus der Validierung der Analysenmethode und den Ergebnissen verschiedener Probennahmen werden Toleranzbereiche für die Ergebnisse eines Grundwassermonitorings abgeschätzt. Diese Streubreiten von Monitoring- Ergebnissen sollten von Ingenieurbüros und zuständigen Ordnungsbehörden bei der Bewertung der komplexen Abbauprozesse eines LHKW-Grundwasserschadens beachtet werden. KW - Passive sampling KW - Active sampling KW - Groundwater KW - Trichloroethene KW - Vinyl chloride KW - Methane PY - 2010 U6 - https://doi.org/10.1007/s00767-010-0144-7 SN - 1430-483X VL - 15 IS - 4 SP - 231 EP - 239 PB - Springer CY - Berlin ; Heidelberg AN - OPUS4-22617 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dorgerloh, Ute A1 - Theißen, H. A1 - Becker, Roland A1 - Nehls, Irene T1 - Probenahme von LHKW in Grundwasser: Vergleich von aktiver und passiver Probenahme KW - Grundwasser KW - Probenahme KW - LHKW KW - Pumpprobe KW - Diffusionsprobe KW - PDB PY - 2009 SN - 1618-3258 SN - 1617-5301 VL - 15 IS - 4 SP - 85 EP - 87 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-20624 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riddell, N. A1 - Becker, Roland A1 - Chittim, B. A1 - Emmerling, Franziska A1 - Köppen, Robert A1 - Lough, A. A1 - McAlees, A. A1 - McCrindle, R. T1 - Preparation and X-ray structural characterization of further stereoisomers of 1,2,5,6,9,10-hexabromocyclododecane N2 - Technical 1,2,5,6,9,10-hexabromocyclododecane (HBCD) consists largely of three diastereomers (α-, β-, and γ-HBCD) produced by the trans addition of bromine to cis,trans,trans-cyclododeca-1,5,9-triene (CDT). However, another seven diastereomers are theoretically possible and may be produced by trans addition of bromine across the double bonds of the other three isomers of 1,5,9-CDT. There are indications that small amounts of the minor HBCD isomers may be present in commercial HBCD mixtures or in products containing this brominated flame retardant (BFR). Such minor components may indeed derive from traces of other 1,5,9-CDTs in the cis, trans, trans starting material, however their formation may also be possible through isomerizations during the processing of this BFR or by bioisomerization subsequent to its release into the environment. Two of the seven additional diastereomers (δ- and ε-HBCD) were synthesized previously from trans,trans,trans-CDT. We now report the preparation of the remaining five diastereomers, ζ-, η-, and θ-HBCD from cis,cis,trans-CDT and ι- and κ-HBCD from cis,cis,cis-CDT, and their characterization by 1H NMR spectroscopy and X-ray crystallography. The availability of these further diastereomers of HBCD should aid in determining if the minor isomers are present in commercial samples of this BFR, in products containing HBCDs, or in environmental samples. We have also carried out an X-ray crystal structure determination on ε-HBCD, so that crystal structures are now available for all 10 HBCD diastereomers. KW - Brominated flame retardants KW - HBCDs KW - Minor isomers KW - X-ray PY - 2011 U6 - https://doi.org/10.1016/j.chemosphere.2011.06.014 SN - 0045-6535 SN - 0366-7111 VL - 84 IS - 7 SP - 900 EP - 907 PB - Elsevier Science CY - Kidlington, Oxford AN - OPUS4-24298 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weber, M. A1 - Durmaz, V. A1 - Becker, Roland A1 - Esslinger, Susanne T1 - Predictive identification of Pentabromocyclododecene (PBCD) isomers with high binding affinity to hTTR N2 - The binding affinities of the six main hexabromocyclododecane (HBCD) stereoisomers and all of their possible 48 allylic pentabromocyclododecene (PBCD) metabolites to the endocrinous human transthyretin receptor (hTTR) were investigated and compared to the natural binder thyroxine, and the two brominated diphenyl ethers BDE-47 and 3-hydroxy-BDE-47. The endocrine disrupting potency was approximated by a combination of two methods: a surface matching with the natural binder thyroxine (T4) followed by approximation of free binding energies for various binding modes within hTTR. The results indicate slightly higher binding affinities for both BDE structures than for T4 itself and similarly high affinities for two trans-configurated PBCD isomers. For many other PBCD isomers, intermediate values were computed, whereas all HBCD diastereomers yielded significantly lower binding affinities. T2 - Dioxin 2009 - 29th International symposium on halogenated persistent organic pollutants / Organohalogen compounds CY - Beijing, China DA - 2009-08-23 KW - Flammschutzmittel KW - Thyroxin KW - Molecular modeling PY - 2009 UR - http://www.dioxin20xx.org/pdfs/2009/09-54.pdf VL - 71 SP - 000247 EP - 000252 CY - Beijing, China AN - OPUS4-20980 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Weber, M. A1 - Durmaz, V. A1 - Esslinger, Susanne T1 - Predictive identification of pentabromocyclododecane (PBCD) isomers with high binding affinity to hTTR T2 - 29th International Symposium on Halogenated Persistent Organic Pollutants (Dioxin 2009) CY - Beijing, China DA - 2009-08-23 PY - 2009 AN - OPUS4-19656 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scharkoi, O. A1 - Becker, Roland A1 - Esslinger, Susanne A1 - Weber, M. A1 - Nehls, Irene T1 - Predicting sites of cytochrome P450-mediated hydroxylation applied to CYP3A4 and hexabromocyclododecane N2 - This article describes a simple and quick in silico method for the prediction of cytochrome P450 (CYP)-mediated hydroxylation of drug-like compounds. Testosterone and progesterone, two known substrates of CYP3A4, are used to test the method. Further, we apply the procedure to predict sites of hydroxylation of isomers of the flame retardant hexabromocyclododecane by CYP3A4. Within the method, the compound is rotated in the binding pocket of the cytochrome, so that each hydrogen under consideration is placed near the active centre. Afterwards, short molecular dynamics simulations are provided for each step of the rotation. All steps of the simulation are compared concerning the distances between the hydrogens and the active centre and the corresponding energies. The computational results correlate well with experimental results. KW - Predicting sites of metabolism KW - Cytochrome P450 KW - Hydroxylation KW - Metabolism of HBCD PY - 2015 U6 - https://doi.org/10.1080/08927022.2014.898845 SN - 0892-7022 SN - 1029-0435 VL - 41 IS - 7 SP - 538 EP - 546 PB - Gordon and Breach CY - New York, NY AN - OPUS4-30492 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sichler, Theresa Constanze A1 - Adam, Christian A1 - Becker, Roland A1 - Sauer, Andreas A1 - Ostermann, Markus A1 - Barjenbruch, M. T1 - Phosphorus determination in sewage sludge: comparison of different aqua regia digestion methods and ICP-OES, ICP-MS and photometric determination N2 - Phosphorus recycling from sewage sludge will be obligatory in Germany from 2029. Phosphorus content determination in sewage sludge is crucial to assess the prescribed recycling rates. Currently, German law regards sample preparation using aqua regia digestion in a microwave or under reflux conditions as well as instrumental phosphorus determination by ICP-OES, ICP-MS, or photometric determination with ammonium molybdate as equivalent. However, it is questionable whether these methods are indeed equivalent regarding phosphorus quantification in sludges near the limit of 20 g/kg for mandatory recycling. To answer this question, 15 sewage sludges of 11 different wastewater treatment plants were investigated with all permitted method (digestion and measurement) combinations. Moreover, one sewage sludge was also examined in an interlaboratory comparison (ILC) with 28 participants. This study shows that the above-mentioned methods differ in some cases significantly but across all method combinations and sludges, phosphorus recovery was between 80 and 121% after normalization to the grand mean (average of 15 sludges between 85 and 111%). The ILC and the examination of 15 sludges produced largely similar results. There is a tendency to higher phosphorus recovery after microwave digestion compared to reflux digestion and ICP-OES measurements determine higher phosphorus contents than ICP-MS and photometric phosphorus determination. As a result, the authors recommend ICP-OES determination of phosphorus in sewage sludge after microwave digestion. KW - Sewage sludge KW - ICP-OES KW - Phosphous recovery KW - ICP-MS KW - Photometric P determination KW - Interlaboratory comparison PY - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-558869 VL - 34 IS - 99 SP - 1 EP - 14 PB - Springer AN - OPUS4-55886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reck, Günter A1 - Becker, Roland T1 - Phenanthroline complexes of zinc and calcium carbamates N2 - Bis(N,N-di-n-butyl­di­thio­carbamato-?2S,S')(1,10-phenanthroline-?2N,N')­zinc(II) ethanol hemisolvate, [Zn(C9H18NS2)2(C12H8N2)]·0.5C2H6O, (I), and bis(N,N-di-n-hexyldithiocarbamato-?2S,S')­bis(1,10-phenanthroline-?2N,N')calcium(II), [Ca(C13H26NS2)2(C12H8N2)2], (II), are mixed-ligand com­plexes. In the first compound, the Zn atom has a distorted octahedral coordination, while in the second compound, the Ca atom is eight-coordinate, with four S and four N atoms forming a highly distorted cube. KW - X-ray structure analyses KW - Metal-organic complexes KW - Antioxidant properties PY - 2004 U6 - https://doi.org/10.1107/S0108270104001441 SN - 0108-2701 SN - 1600-5759 VL - 60 SP - m134 EP - m136 PB - Blackwell Publ. CY - Oxford AN - OPUS4-3110 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scharkoi, O. A1 - Esslinger, Susanne A1 - Becker, Roland A1 - Weber, M. A1 - Nehls, Irene T1 - Phase I oxidation of alpha- and gamma-hexabromocyclododecane by cytochrome P450 enzymes: simulation of the steroisomerism of hydroxylated metabolites T2 - DIOXIN 2011 CY - Brussels, Belgium DA - 2011-08-21 KW - Bromierte Falmmschutzmittel KW - Hexabromcyclododecan KW - Cytochrom KW - Metaboliten KW - HPLC KW - Simulation PY - 2011 UR - http://www.dioxin20xx.org/pdfs/2011/1810.pdf SN - 1026-4892 VL - 73 SP - 730 EP - 733 AN - OPUS4-27263 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Scharkoi, O. A1 - Esslinger, Susanne A1 - Weber, M. A1 - Nehls, Irene T1 - Phase I Oxidation of alpha- and gamma-Hexabromocyclodeodecane by Cytochrome P450 Enzymes: Simulation of the Stereoisomerism of Hydroxylated Metabolites T2 - DIOXIN 2011, 31st International Symposium on Halogenated Persistent Organic Pollutants CY - Brussels, Belgium DA - 2011-08-21 PY - 2011 AN - OPUS4-23823 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Walther, Wolfgang A1 - Becker, Roland A1 - Nehls, Irene A1 - Lehmann, Andreas A1 - Redlich, Christel A1 - Flemig, Sabine A1 - Dorgerloh, Ute A1 - Win, Tin A1 - Buge, Hans-Gerhard T1 - Pentchlorophenol (PCP) in Soil - Certified Reference Materials for Environmental Analysis T2 - Analytica Conference 2002 CY - Munich, Germany DA - 2002-04-23 PY - 2002 SP - 1(?) AN - OPUS4-1389 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -