Aufsätze

Dauerhafte URI für die Sammlunghttps://openumwelt.de/handle/123456789/6

Listen

Filter

2015 - 201922020 - 20221

Einstellungen

Thema: search.filters.subject.Wasser

Suchergebnisse

Gerade angezeigt 1 - 3 von 3
  • Vorschaubild nicht verfügbar
    Veröffentlichung
    Round robin test for odour testing of migration waters
    (2015) Günther, Herbert; Rapp, Thomas
    For a round robin test for EN 1420-1 (Odour assessment for organic materials in contact with drinking water) with 14 contributing laboratories from 10 European countries segments of a plastic pipe were sent to the laboratories which performed a migration test and an odour analysis of the migration waters (water that had contact with the organic material) according to the procedure described in the standard from 1999. In addition reference substances (Methyl tert-butyl ether, 1-butanol and hexanal) were investigated for their suitability to qualify the panels and the individual panellists. Methyl tert-butyl ether (MtBE) and 1-butanol proved to be suitable for this purpose, whereas hexanal showed a wide distribution of the individual odour threshold concentrations. Both possible testing options (unforced and forced choice) were performed and gave similar results. However, with respect to the qualification of the panellists and the data analysis the unforced choice procedure showed advantages. As human olfactory perception is used for the analysis, the reproducibility and the comparability between laboratories is of particular concern. For the pipe material the TON results of the different laboratories were in a range of ş1.5 dilutions based on a dilution factor of 2. This might be improved by taking the individual sensitivities of the panellists into account more strongly. Appropriate measures for the improvement of the test method appear to be the use of the proposed reference substances for the training of the panellists as well as the auditing and the selection of the panellists. The results of this round robin test are used in the revision process of the standard.Quelle: http://www.sciencedirect.com
  • Vorschaubild nicht verfügbar
    Veröffentlichung
    Development and testing of a fractionated filtration for sampling of microplastics in water
    (2019) Bannick, Claus Gerhard; Obermaier, Nathan; Ricking, Mathias; Schniegler, Sara; Szewzyk, Regine; Barthel, Anne-Kathrin
    A harmonization of sampling, sample preparation and detection is pivotal in order to obtain comparable data on microplastics (MP) in the environment. This paper develops and proposes a suitable sampling concept for waterbodies that considers different plastic specific properties and influencing factors in the environment. Both artificial water including defined MP fractions and the discharge of a wastewater treatment plant were used to verify the derived sampling procedure, sample preparation and the subsequent analysis of MP using thermal extraction-desorption gas chromatography - mass spectrometry (TED-GC-MS). A major finding of this paper is that an application of various particle size classes greatly improves the practical handling of the sampling equipment. Size classes also enable the TED-GC-MS to provide any data on the MP size distribution, a substantial sampling property affecting both the necessary sampling volume and the optimal sampling depth. In the artificial body of water with defined MP fractions, the recovery rates ranged from 80-110%, depending on the different MP types and MP size classes. In the wastewater discharge, we found both polyethylene and polystyrene in different size classes and quantities. © 2018 Elsevier Ltd. All rights reserved.
  • Vorschaubild nicht verfügbar
    Veröffentlichung
    Biomonitoring of arsenic, cadmium and lead in two artisanal and small-scale gold mining areas in Zimbabwe
    (2022) Rakete, Stefan; Moonga, Given; Wahl, Anna-Maria; Tobollik, Myriam
    People living and working in artisanal and small-scale gold mining (ASGM) areas are frequently exposed to elemental mercury (Hg), which is used for gold extraction. However, additional exposure to other toxic metals such as arsenic (As), cadmium (Cd) and lead (Pb) may result from mining-related activities and could be ingested via dust, water or food. In these areas, only limited biomonitoring data is available for toxic metals other than Hg. In particular, data about the exposure to As, Cd and Pb is unavailable for the Zimbabwean population. Therefore, we conducted a cross-sectional study in two ASGM areas in Zimbabwe to evaluate the internal exposure to these metals. In total, urine and blood samples from 207 people that identified themselves as miners were collected and analysed for As and Cd in urine as well as Pb in blood by GF-AAS. Median levels (interquartile ranges in (micro)g/l) of As and Pb were 9.7 (micro)g/l (4.0, 18.5) and 19.7 (micro)g/l (12.5, 34.5), respectively. The 25th percentile and the median for Cd were below the limit of detection (0.5 (micro)g/l); the 75th percentile was at 0.9 (micro)g/l. The results were compared to reference values found for the general population in the USA and Germany, and a significant number of participants exceeded these values (As, 33 %; Cd, 27 %; Pb, 32 %), indicating a relevant exposure to toxic metals. Although not representative for the Zimbabwean population, our results demonstrate that the exposure to toxic metals is relevant for the public health in Zimbabwe and requires further investigation. © 2021, The Author(s)