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 DO - 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 - JOUR A1 - Becker, Roland A1 - Dorgerloh, Ute A1 - Helmis, M. A1 - Mumme, J. A1 - Diakité, M. A1 - Nehls, Irene T1 - Hydrothermally carbonized plant materials: Patterns of volatile organic compounds detected by gas chromatography N2 - The nature and concentrations of volatile organic compounds (VOCs) in chars generated by hydrothermal carbonization (HTC) is of concern considering their application as soil amendment. Therefore, the presence of VOCs in solid HTC products obtained from wheat straw, biogas digestate and four woody materials was investigated using headspace gas chromatography. A variety of potentially harmful benzenic, phenolic and furanic volatiles along with various aldehydes and ketones were identified in feedstock- and temperature-specific patterns. The total amount of VOCs observed after equilibration between headspace and char samples produced at 270 °C ranged between 2000 and 16,000 µg/g (0.2–1.6 wt.%). Depending on feedstock 50–9000 µg/g of benzenes and 300–1800 µg/g of phenols were observed. Substances potentially harmful to soil ecology such as benzofurans (200–800 µg/g) and p-cymene (up to 6000 µg/g in pine wood char) exhibited concentrations that suggest restrained application of fresh hydrochar as soil amendment or for water purification. KW - Hydrochar KW - Mass spectrometry KW - Flame ionization detection KW - Phenols KW - Benzenes PY - 2013 DO - https://doi.org/10.1016/j.biortech.2012.12.102 SN - 0960-8524 SN - 1873-2976 VL - 130 SP - 621 EP - 628 PB - Elsevier Applied Science CY - Barking, Essex AN - OPUS4-27616 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 DO - 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 - JOUR A1 - Dorgerloh, Ute A1 - Becker, Roland A1 - Nehls, Irene T1 - Determination of volatile organic sulfur compounds in contaminated groundwater N2 - A practical method for the quantification of total purgeable organic sulfur (POS) in highly contaminated groundwater is described. Volatile organic sulfur compounds (VOSC) are purged from the water samples by a stream of oxygen and combusted. The emerging sulfur dioxide is absorbed in H2O2 and converted to sulfate which is quantified by ion chromatography and reported as mass sulfur equivalent. The overall limit of quantification is 0.03 mg l–1. The content of POS is balanced with the total VOSC determined by GC-AED after liquid–liquid extraction. Separate determination of the non-volatile organic sulfur compounds by direct combustion of the water sample and adsorption to charcoal yielded a mass balance of the total sulfur content. Semi-quantitative GC-MS after purge & trap accumulation revealed that the VOSC mixture is composed of C1–C4 alkyl sulfides. The implementation of the developed methodology for the quantification of VOSC as potential catalyst poison in a cleaning plant for groundwater contaminated with volatile haloorganics (VOX) is presented. KW - Contamination KW - Remediation KW - Summation parameter KW - Combustion KW - Ion chromatography KW - GC-AED KW - GC-MS PY - 2008 UR - http://www.springerlink.com/content/8612g42hwj7130g8/fulltext.pdf DO - https://doi.org/10.1007/s10311-007-0117-y SN - 1610-3653 SN - 1610-3661 VL - 6 IS - 2 SP - 101 EP - 106 PB - Springer CY - Berlin AN - OPUS4-16360 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dorgerloh, Ute A1 - Becker, Roland A1 - Lutz, A. A1 - Bremser, Wolfram A1 - Hilbert, S. A1 - Nehls, Irene T1 - How to improve reliability in groundwater analysis: over a decade of experience with external quality control in field campaigns on volatile halogenated compounds N2 - The reliability in measurement results obtained during environmental monitoring is crucial for the assessment and further planning of remediation efforts on the respective contaminated sites by the responsible authorities. A case study concerned with groundwater contaminated with perchloroethylene, trichloroethylene and 1,1,2-trichlorotrifluoroethane including their degradation products which involves private contract laboratories and an independent provider of quality assurance (QA) is presented. The experience gained with biannual monitoring campaigns over 14 years indicates that the selection of contractors on basis of accreditation status and successful performance in interlaboratory comparisons are not sufficient. Rather the auditing of the contractors by the QA provider prior to each campaign and the crosschecking of selected monitoring samples by the QA provider led to a lasting improvement of reliability in the contractors' measurement results. A mean deviation of 20% from the reference value determined by the QA provider for the crosschecked samples was reached. KW - Groundwater monitoring KW - External quality management KW - QM KW - VOC PY - 2012 DO - https://doi.org/10.1039/c1em10460h SN - 1464-0325 SN - 1464-0333 VL - 14 IS - 1 SP - 217 EP - 223 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-25288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dorgerloh, Ute A1 - Becker, Roland A1 - Nehls, Irene T1 - Ringversuche: Präparation mineralölkohlenwasserstoffhaltiger Wasserproben T2 - GDCh Jahrestagung, Wasserchemische Gesellschaft CY - Trier, Germany DA - 2008-04-28 PY - 2008 AN - OPUS4-16731 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dorgerloh, Ute A1 - Becker, Roland T1 - Flüchtige Kohlenwasserstoffe in Boden - Stand der Technik und seine Grenzen N2 - Die inhalative Aufnahme (Wirkungspfad Boden – Mensch) von MKW bestimmt aus toxikologischer Sicht die Festlegung von Prüfwerten. Somit müssen die leichtflüchtigen Fraktionen quantifiziert werden. Die durchgeführte Robustheitsstudie des genormten Verfahrens umfasst die Ermittlung der Kenndaten der Probenahme, der Probenaufarbeitung und der Instrumentalanalytik. T2 - DECHEMA - Symposium Strategien zur Sanierung von Boden und Grundwasser CY - Frankfurt a.M., Germany DA - 20.11.2017 KW - Flüchtige Kohlenwasserstoffe KW - Kohlenwasserstofffraktionen KW - Bodenanalytik PY - 2017 AN - OPUS4-42943 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dorgerloh, Ute A1 - Becker, Roland A1 - Nehls, Irene A1 - Brodsky, J. T1 - Robustheitsstudie ISO 16558-1: Leichtflüchtige Kohlenwasserstoffe in Boden T2 - Altlastensymposium CY - Frankfurt am Main DA - 2015-11-30 PY - 2015 AN - OPUS4-34669 LA - deu 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 DO - 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 -