TY - JOUR A1 - Ammann, Dominic A1 - Becker, Roland A1 - Kohl, Anka A1 - Hänisch, Jessica A1 - Nehls, Irene T1 - Degradation of the ethyl glucuronide content in hair by hydrogen peroxide and a non-destructive assay for oxidative hair treatment using infra-red spectroscopy N2 - The assessment of quantification results of the alcohol abuse marker ethyl glucuronide (EtG) in hair in comparison to the cut-off values for the drinking behavior may be complicated by cosmetic hair bleaching. Thus, the impact of increasing exposure to hydrogen peroxide on the EtG content of hair was investigated. Simultaneously, the change of absorbance in the range of 1000–1100 cm-1 indicative for the oxidation of cystine was investigated non-destructively by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) using pulverized portions of the respective hair samples. Hair samples treated with hydrogen peroxide consistently displayed a significantly increased absorbance at 1040 cm-1 associated with the formation of cysteic acid. The EtG content decreased significantly if the hair was treated with alkaline hydrogen peroxide as during cosmetic bleaching. It could be shown that ATR-FTIR is capable of detecting an exposure to hydrogen peroxide when still no brightening was visible and already before the EtG content deteriorated significantly. Thus, hair samples suspected of having been exposed to oxidative treatment may be checked non-destructively by a readily available technique. This assay is also possible retrospectively after EtG extraction and using archived samples. KW - Hair testing KW - Oxidation KW - Bleaching KW - Cysteic acid KW - HPLC–MS/MS PY - 2014 DO - https://doi.org/10.1016/j.forsciint.2014.07.029 SN - 0379-0738 SN - 1872-6283 VL - 244 SP - 30 EP - 35 PB - Elsevier CY - Amsterdam [u.a.] AN - OPUS4-31755 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 DO - 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 - Buge, Hans-Gerhard A1 - Bremser, Wolfram A1 - Nehls, Irene T1 - Mineral oil content in sediments and soils: comparability, traceability and a certified reference material for quality assurance N2 - The performance of twelve laboratories with previously established proficiency in the determination of the mineral oil content in a fresh water sediment is described. The summation parameter total petrol hydrocarbon (TPH) is defined according to ISO 16703:2004 with regard to the sample preparation to be applied, the flame ionisation detection (FID) and the boiling range of C10–C40 to be integrated. Comprehensive tests of homogeneity and stability have been carried out on the candidate material using appropriate models. The outcome of the study served as the basis for the certification of the candidate reference material as ERM-CC015a. The certified mass fraction is 1,820±130mgkg-1 and traceability was established by using an appropriate calibration standard certified for the mass fraction of C10–C40. The interlaboratory scatter of measurement results in this exercise can largely be explained by the variability of the individual calibrations based on this common calibration standard. KW - Total petroleum hydrocarbons KW - Extraction KW - Gas chromatography KW - Calibration KW - Interlaboratory study PY - 2006 DO - https://doi.org/10.1007/s00216-006-0423-4 SN - 1618-2642 SN - 1618-2650 VL - 385 IS - 3 SP - 645 EP - 651 PB - Springer CY - Berlin AN - OPUS4-12399 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 DO - 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 - 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 - Becker, Roland A1 - Dorgerloh, Ute A1 - Paulke, E. A1 - Mumme, J. A1 - Nehls, Irene T1 - Hydrothermal carbonization of biomass: Major organic components of the aqueous phase N2 - Process waters obtained from hydrothermal carbonization (HTC) of wheat straw, a biogas digestate derived thereof, and four woody biomass feedstocks were quantified regarding the total organic carbon (TOC) and selected organic compounds. HTC runs revealed that TOC loads were largely unaffected by process severity or type of feedstock whereas the C2–C6 fatty acids, determined by GC, displayed clear effects of temperature and feedstock. HPLC demonstrated simultaneously the initial increase and subsequent consumption of cellulose-derived furfural and 5-hydroxymethylfurfural as well as the increase of the lignin-derived 2-methoxyphenol. 2-Methylbenzofuran, an example for a substance potentially harmful to aquatic biota, was observed in high concentration in the HTC liquor from wheat straw-based feedstocks. KW - Furfurals KW - Gas chromatography KW - Liquid chromatography KW - Phenols KW - Process water KW - Total organic carbon PY - 2014 DO - https://doi.org/10.1002/ceat.201300401 SN - 0930-7516 SN - 1521-4125 VL - 37 IS - 3 SP - 511 EP - 518 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-30333 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 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 - RPRT A1 - Becker, Roland A1 - Koch, Matthias A1 - Buge, Hans-Georg A1 - Nehls, Irene T1 - Entwicklung eines Referenzverfahrens zur Quantifizierung von polychlorierten Biphenylen (PCB) in Kunststoffgranulaten N2 - Im Rahmen eines vom Bundesministerium für Wirtschaft und Arbeit (BMWA) geförderten Projektes wird in Kooperation mit dem Verband deutscher Metallhändler (VDM) ein Verfahren zur Quantifizierung der PCB-Kongenere 28, 52, 101, 138, 153, 180 im Gehaltsbereich von 0,1 bis 20 mg in Kunststoffabfällen aus dem Altkabelrecycling entwickelt und validiert. Dazu werden repräsentative Referenzmaterialien für die Laboranalytik aus Granulaten verschiedener Kabelzerlegeprozesse hergestellt und charakterisiert. Die Methodenentwicklung umfasst mahl-, sieb- und schüttguttechnologische Aspekte sowie den Vergleich unterschiedlicher Extraktionsverfahren und chromatographischer Bedingungen. Das validierte Verfahren sieht die Mahlung der technischen Probe auf eine Kornobergrenze von 0,50 mm gefolgt von Extraktion mit einem unpolaren Lösungsmittel bei einer Einwaage von 4 g und gaschromatographischer Bestimmung vor. Die Bestimmungsgrenzen liegen zwischen 0,01 und 0,08 mg/kg. Bei sorgfältiger Wahl der chromatographischen Bedingungen sind Elektroneneinfang- und massenselektive Detektion (MS) gleichwertig. In Gegenwart größerer Mengen bestimmter Komponenten, die in einigen Kabeln enthalten sind, kann der Einsatz eines MS von Vorteil sein. Drei Referenzmaterialien mit Gehalten der genannten Kongenere zwischen 0,1 bis 5 mg/kg werden in einem abschließenden Ringversuch zur Validierung dieser Methode mit 23 ausgewählten Laboratorien eingesetzt. Dabei ergeben sich für die Quantifizierung dieser Kongenere relative Vergleichsstandardabweichungen zwischen 15 und 33 %. Das Verfahren wird in die europäische Normung (CEN 292 „Characterisation of Waste“) eingebracht. T3 - BAM Forschungsberichtreihe - 270 PY - 2005 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-1810 SN - 978-3-86509-320-5 SN - 0938-5533 VL - 270 SP - 1 EP - 107 PB - Wirtschaftsverlag NW CY - Bremerhaven AN - OPUS4-181 LA - deu 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 DO - 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 - 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 - JOUR A1 - Becker, Roland A1 - Nehls, Irene A1 - Dorgerloh, Ute T1 - Interlaboratory comparisons - demonstrating degree of equivalence N2 - The role of matrix reference materials in the process of demonstrating the degree of equivalence of measurement results obtained from intercomparisons is outlined, reviewing exemplary selected experience gained at BAM regarding the determination of organic contaminants in environmental matrices. The specific characteristics of reference materials employed in the process of demonstrating equivalence between laboratories in the course of proficiency testing as well as the development, comparison and validation of methods are elaborated. The demand is for series of appropriately characterised samples which are fit for the purpose and it is seen from representative examples that the utilisation of such tailor-made RM designed to tackle the specific need of an analytical problem dominates over certified matrix reference materials in this context. Concluding, the role of certified matrix reference materials in quality assurance is briefly looked at both from the user’s and providers’ points of view. KW - Certification KW - Equivalence KW - Method development KW - Proficiency testing KW - Reference materials PY - 2003 DO - https://doi.org/10.1007/s00769-003-0580-5 SN - 0949-1775 SN - 1432-0517 VL - 8 SP - 150 EP - 155 PB - Springer CY - Berlin AN - OPUS4-2848 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 - 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 - 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 DO - 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 - 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 - 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 - 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 - Erhardt, Ulla A1 - Schmieder, Rosmarie A1 - Walter, W. A1 - Win, Tin A1 - Hilbert, S. A1 - Mechler, M. A1 - Nehls, Irene T1 - Ringversuch zur Bestimmung von leichtflüchtigen halogenierten Kohlenwasserstoffen (LHKW), Vinylchlorid (VC) und Fluorchlorkohlenwasserstoffen (FCKW) in Grundwasser KW - Analytik KW - Grundwasser KW - Leichtflüchtige halogenierte Kohlenwasserstoffe (LHKW) KW - Vinylchlorid (VC) KW - Fluorchlorkohlenwasserstoffe (FCKW) KW - Ringversuch KW - Analytics KW - Groundwater KW - Highly volatile halogenated hydrocarbons (VHHC) KW - Vinyl chloride (VC) KW - Chlorofluorocarbons (CFC) KW - Interlaboratory comparison PY - 2004 SN - 0083-6915 VL - 102 IS - 2 SP - 12 EP - 16 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-4126 LA - deu 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 DO - 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 - CONF A1 - Dorgerloh, Ute A1 - Theißen, H. A1 - Becker, Roland A1 - Nehls, Irene T1 - Das Problem löst sich von selbst: Stabilisierung von Grundwasserproben zur Bestimmung organischer Inhaltsstoffe N2 - Als Folge der industriellen Produktion und der vielfältigen industriellen Nutzung von organischen Lösungsmitteln sind eine Vielzahl von Edukten, Zwischen- und Endprodukten in die Umwelt eingetragen worden und führen zu massiven Verunreinigungen des Bodens und des Grundwassers. Die Untersuchung und Sanierung des Grundwassers stellt einen aktuellen Schwerpunkt in der Altlastenbearbeitung dar. Vielfach werden klassische pump & treat-Verfahren zur Grundwassersanierung verwendet. Diese aktiven Sicherungs- und Sanierungsmaßnahmen werden jedoch unter dem Gesichtspunkt der Verhältnismäßigkeit häufig als ineffizient eingeschätzt. Als Alternative sollen die natürlichen Abbauprozesse im Grundwasserleiter genutzt oder gezielt verstärkt werden, um auf diesem Weg eine in-situ-Sanierung des Grundwasserleiters zu erreichen. In den letzten Jahren haben sich verschiedene Sanierungsverfahren etabliert, bei denen durch die Zugabe von Hilfsstoffen die mikrobiologische Aktivität des Aquifers erhöht wird bzw. Stoffe zugeführt werden, die mit den Schadstoffen reagieren (in-situ chemische Oxidation bzw. Reduktion, ISCO). An ausgewählten Standorten ist auch die aktive Sanierung (pump & treat, on-site- Sanierung) mit biologischem Schadstoffabbau (Bio-Filter) kombiniert worden. Um den Sanierungsverlauf zu verfolgen und zu optimieren, ist die Beprobung von Grundwasser aus dem Grundwasserleiter oder aus laufenden Anlagen erforderlich. In Fällen der gesteigerten mikrobiologischen Aktivität des Grundwassers treten gehäuft Probleme bei der Stabilisierung der Wasserproben auf. Die forcierten Abbauprozesse der Schadstoffe gehen nach der Probenahme in der Probenflasche weiter, bis die Energiebasis der Mikrobiologie aufgebraucht ist. Durch eine geringe Temperaturerhöhung beschleunigen sich diese Prozesse zusätzlich. In der Folge können die Schadstoffgehalte teilweise innerhalb weniger Stunden stark reduziert werden. Im Analysenlabor wird dann ein Schadstoffgehalt nachgewiesen, der nicht mehr die Verhältnisse im Aquifer bzw. im Ablauf der Reinigungsstufen widerspiegelt. Eine Einschätzung des Sanierungsfortschritts oder der Reinigungsleistung ist unter diesen Bedingungen stark fehlerbehaftet und kann zu groben Fehlinterpretationen führen. Grundwasserproben, die einem Aquifer mit hoher natürlicher oder initiierter mikrobiologischer Abbauaktivität entstammen, müssen daher zusätzlich stabilisiert werden, um den Ist-Zustand zum Zeitpunkt der Probenahme zu erfassen. Die Konservierung von Wasserproben bei der Probenahme von Grundwasser ist in der Normung umfangreich beschrieben: Die EN ISO 5667-3 von 2004 ist im Normausschuss (NA 119-01-03-01-01) überarbeitet und 2012 als Norm verabschiedet worden (EN ISO 5667-3, 03.12, deutsche Fassung DIN EN ISO 5667-3, 03-2013) [1], In Einzelfällen hat sie sich nicht als ausreichend erwiesen, um die Stabilität der organischen Schadstoffe in den oben beschriebenen Wasserproben zu gewährleisten. T2 - Altlastensymposium 2014 CY - Fulda, Germany DA - 20.03.2014 KW - Grundwasser KW - In-situ-Sanierung KW - Probenahme KW - Stabilisierung PY - 2014 SP - 76 EP - 85 AN - OPUS4-30480 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -