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 - Fischer-Tenhagen, C. A1 - Johnen, D. A1 - Nehls, Irene A1 - Becker, Roland T1 - A Proof of Concept: Are Detection Dogs a Useful Tool to Verify Potential Biomarkers for Lung Cancer? N2 - Early and reliable diagnostic test is essential for effective therapy of lung cancer. Volatile organic compounds that are characteristic for cancer could serve as valuable biomarkers in cancer diagnosis. Both trace analytical and detection dog approaches give some evidence for the existence of such biomarkers. In this proof of concept, study dogs and trace analysis were implemented in combination to gain more information concerning cancer biomarkers. Two dogs were trained to distinguish between absorbed breath samples of lung cancer patients and healthy persons and succeeded with correct identification of patients with 9/9 and 8/9 and correct negative indications from of 8/10 and 4/10 samples from healthy individuals. A recent observational study found that breath samples from lung cancer patients showed an increase in 1-butanol, 2-butanone, 2-pentanone, and hexanal. Synthetic air samples were therefore fortified with these compounds and adsorbed to a fleece. Tested against breath samples from healthy probands, on presentation to the dogs these synthetic samples provoked an indication in three out of four samples. We were able to demonstrate that a combination of the natural nose of a dog and a trace analytic technique can be a valuable concept in the search for cancer biomarkers. KW - Lung cancer KW - Breath KW - Detection dog KW - Biomarkers KW - Sampling KW - Synthetic air PY - 2018 DO - https://doi.org/10.3389/fvets.2018.00052 SN - 2297-1769 VL - 5 SP - Article 52,1 EP - 6 PB - Frontiers Research Foundation CY - Lausanne AN - OPUS4-44466 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 DO - 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 - Mekonnen, Tessema F. A1 - Byrne, Liam A1 - Panne, Ulrich A1 - Koch, Matthias T1 - Investigation of chlorpyrifos and its transformation products in fruits and spices by combining electrochemistry and liquid chromatography coupled to tandem mass spectrometry N2 - The identification of transformation products (TPs) of pesticides in food is a crucial task difficult to tackle, due to the lack of standards. In this work, we present a novel methodology to synthesize five main TP standards of the insecticide chlorpyrifos (CPF) and to investigate their occurrence in selected fruits and spices. TPs were electrochemically (EC) synthesized using a boron-doped diamond electrode (BDD) and identified by EC coupled online to mass spectrometry, LC-MS/MS, and high-resolution mass spectrometry. CPF and its TPs were analyzed in the food samples by LC-MS/MS on multiple reaction monitoring (MRM) after dispersive solid-phase extraction. A good recovery of 83–103% for CPF and 65–85% for TPs was obtained. Matrix effects, which cause signal suppression, ranged between 81 to 95% for all targeted analytes. The limit of detection and quantification for CPF were 1.6–1.9 and 4.9–5.7 μg/kg, respectively. Among investigated samples, CPF was determined in fresh lemon (104 μg/kg), fenugreek seed (40 μg/kg), and black pepper (31 μg/kg). CPF content in all samples was lower than the EU maximum residue level (MRL). The most frequently detected TPs were diethylthiophosphate and diethylphosphate. Other TPs, CPF oxon and trichloropyridinol, were also detected. Hence, EC is a versatile tool to synthesize TP standards which enables the determination of contaminants and residues in foodstuffs even if no commercial standards are available. KW - Transformation product KW - Electrochemistry KW - QuEChERS KW - LC-MS/MS KW - Photodegradation KW - Foodstuffs PY - 2018 UR - https://link.springer.com/article/10.1007/s12161-018-1245-7#citeas DO - https://doi.org/10.1007/s12161-018-1245-7 SN - 1936-9751 SN - 1936-976X VL - 11 IS - 10 SP - 2657 EP - 2665 PB - Springer AN - OPUS4-45834 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mekonnen, Tessema Fenta A1 - Panne, Ulrich A1 - Koch, Matthias T1 - New photodegradation products of the fungicide fluopyram: Structural elucidation and mechanism identification N2 - Identifying the fate of agrochemicals is important to understand their potential risk for living organisms. We report here new photodegradation products (PPs) of the fungicide fluopyram. The PPs were produced by irradiating a fluopyram standard in 0.1% acetonitrile aqueous media by a 150-W medium pressure Hg-lamp that emits wavelengths between 200–280 nm. The structural elucidation of PPs was achieved by combining the retention time, isotopic pattern, targeted fragmentation, and accurate mass measurements using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and high resolution-MS (HRMS). In addition to previously known PPs, seven new PPs of fluopyram were identified in this work: mainly dihydroxyl and hydroxylimide fluopyram as well as mono, di, and trihydroxyl lactam. Additionally, two PPs were found to be formed by rearrangement after the loss of H2C=CH2. Hence, the results of the work contribute to extending the current knowledge regarding the photoinduced fate of agrochemicals, and fluopyram in particular. KW - Photodegradation KW - Transformation products KW - LC-MS/MS KW - HRMS KW - Fungicide PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-466347 DO - https://doi.org/10.3390/molecules23112940 SN - 1420-3049 VL - 23 IS - 11 SP - 2940, 1 EP - 13 PB - MDPI CY - Basel AN - OPUS4-46634 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -