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Veröffentlichung Kunststoffe in der Umwelt(2015)Kunststoffe (besser: synthetische Polymere) sind wichtige Werkstoffe und heutzutage aus Haushalt und Wirtschaft - auch im Bereich Abwassertechnik - nicht mehr wegzudenken. Seit Anfang der 1970er-Jahre wird das Vorkommen von Kunststoffpartikeln in Küstengewässern beschrieben. Inzwischen ist Mikroplastik nicht nur im marinen Bereich, sondern auch in weiteren Umweltkompartimenten nachweisbar. In dieser Arbeit wird ein Überblick über das Vorkommen von Mikroplastik in der Umwelt und dessen Auswirkungen gegeben. Darüber hinaus werden die aktuellen Untersuchungsverfahren betrachtet und offene Fragen. Quelle: http://www.dwa.deVeröffentlichung Mikroplastik in der aquatischen Umwelt(2015)Kunststoffe sind wichtige Werkstoffe und heutzutage aus Haushalt und Wirtschaft nicht mehrwegzudenken. Seit Anfang der 1970er-Jahre wird das Vorkommen von Kunststoffpartikeln inKüstengewässern beschrieben. Inzwischen ist Mikroplastik nicht nur im marinen Bereich,sondern auch in weiteren Umweltkompartimenten, Biota und technischen Einrichtungen derWasserwirtschaft nachgewiesen worden. In dieser Arbeit wird ein Überblick über das Vorkommenvon Mikroplastik in der aquatischen Umwelt und ersten bekannten Auswirkungengegeben. Darüber hinaus werden die aktuellen Untersuchungsverfahren von Probenahme,Probenaufbereitung und Analytik betrachtet und offene Fragen diskutiert. Zentral erscheint indiesem Zusammenhang die Entwicklung einer harmonisierten medienübergreifenden Untersuchungsmethodik,die eine Auswertung relevanter Stoffströme ermöglicht und auf notwendigeBewertungskonzepte abgestimmt ist.Quelle: Bannick, Claus Gerhard et al.: Mikroplastik in der aquatischen Umwelt : ein Beitrag zur aktuellen Diskussion in Deutschland / Claus Gerhard Bannick ; Reinhard Bierl ; Ulrike Braun ; Kathrin Brand ; Erik Dümichen ; Martin Jekel ; Sascha Klein ; Thomas P. Knepper ; Fabian König ; David Miklos ; Bettina Rechenberg ; Ina Steffens. - Ill., graph. Darst. In: Vom Wasser : das Journal. - 113 (2015), H. 1, S. 7Veröffentlichung Analysis of polyethylene microplastics in environmental samples, using a thermal decomposition method(2015) Dümichen, Erik; Bannick, Claus Gerhard; Barthel, Anne-Kathrin; Braun, Ulrike; Brand, Kathrin; Jekel, Martin; Senz, RainerSmall polymer particles with a diameter of less than 5 mm called microplastics find their way into the environment from polymer debris and industrial production. Therefore a method is needed to identify and quantify microplastics in various environmental samples to generate reliable concentration values. Such concentration values, i.e. quantitative results, are necessary for an assessment of microplastic in environmental media. This was achieved by thermal extraction in thermogravimetric analysis (TGA), connected to a solid-phase adsorber. These adsorbers were subsequently analysed by thermal desorption gas chromatography mass spectrometry (TDS-GC-MS). In comparison to other chromatographic methods, like pyrolyse gas chromatography mass spectrometry (Py-GC-MS), the relatively high sample masses in TGA (about 200 times higher than used in Py-GC-MS) analysed here enable the measurement of complex matrices that are not homogenous on a small scale. Through the characteristic decomposition products known for every kind of polymer it is possible to identify and even to quantify polymer particles in various matrices. Polyethylene (PE), one of the most important representatives for microplastics, was chosen as an example for identification and quantification.Quelle: http://www.sciencedirect.comVeröffentlichung The challenge in preparing particle suspensions for aquatic microplastic research(2019) Eitzen, Lars; Paul, Sophia; Braun, Ulrike; Ruhl, Aki SebastianThe occurrence of small particles consisting of organic polymers, so-called microplastic (MP), in aquatic environments attracts increasing interest in both public and science. Recent sampling campaigns in surface waters revealed substantial numbers of particles in the size range from a few micrometers to a few millimeters. In order to validate sample preparation, identification and quantification and to investigate the behavior of MP particles and potential toxic effects on organisms, defined MP model particles are needed. Many studies use spherical compounds that probably behave differently compared to irregularly shaped MP found in environmental samples. However, preparation and handling of MP particles are challenging tasks and have been systematically investigated in the present study. Polystyrene (PS) as a commonly found polymer with a density slightly above that of water was selected as polymer type for milling and fractionation studies. A cryogenic ball mill proved to be practical and effective to produce particles in the size range from 1 to 200 Ìm. The yield of small particles increased with increasing pre-cooling and milling durations. Depending on the concentration and the size, PS particles do not completely disperse in water and particles partly creep vertically up along glass walls. Stabilized MP suspensions without use of surfactants that might harm organisms are needed for toxicological studies. The stabilization of PS particle suspensions with ozone treatment reduced the wall effect and increased the number of dispersed PS particles but increased the dissolved organic carbon concentration and changed the size distribution of the particles. © 2018 Elsevier Inc. All rights reserved.Veröffentlichung Identification and Quantification of Microplastic in Sewage Systems by TED-GC-MS(2019) Altmann, Korinna; Goedecke, Caroline; Bannick, Claus GerhardThe number of publications reporting the amount of microplastic (MP) all over the world increased rapidly. Methods used so far are very time consuming and not able to provide information on total contents. As harmonised sampling, sample preparation and analysis strategies are missing different studies can hardly be compared and quantitative data, including identification and mass contents of the polymers found, are missing. This leads to a lack of comprehensive understanding of MP occurrence, source and entry pathways into the environment. We developed a method, Thermal Extraction/Desorption-Gaschromatography-Massspectrometry, as a fast screening method for MP analysis. Solid residues of water samples are heated up to 600 C under a N2 atmosphere without any sample preparation. The collected decomposition gases are separated in a gas chromatography system and detected in a mass spectrometer. Mass contents of the identified polymers can be calculated. In this presentation we will show first results from the influent of the wastewater treatment plant Kaiserslautern (Germany) and its combined sewage system as possibly entry pathway. In order to determine the relevance of wastewater split streams analysis of grey water will be conducted. Samples are fractionally filtered by a sieve cascade with mesh sizes of 500, 100, 50 Ìm. Quelle: https://opus4.kobv.de/Veröffentlichung Determination of microplastic mass content by thermal extraction desorption gas chromatography-mass spectrometry(2021) Wiesner, Yosri; Altmann, Korinna; Braun, UlrikeThe scientific and practical challenge of detecting microplastics (MPs) in the environment in a targeted and rapid manner is solved by innovative coupling of thermogravimetric analysis with mass spectrometric methods. Fast identification and quantitative determination of most thermoplastic polymers and elastomers is possible by using thermal extraction desorption gas chromatography-mass spectrometry (TED-GC-MS). © AuthorsVeröffentlichung Untersuchungsverfahren von Mikroplastikgehalten im Wasser für Praxis und Wissenschaft(2021) Altmann, Korinna; Braun, Ulrike; Heller, ClaudiaZielsetzung des vom Bundesministerium für Bildung und Forschung geförderten Projektes RUSEKU (Repräsentative Untersuchungsstrategien für ein integratives Systemverständnis von spezifischen Einträgen von Kunststoffen in die Umwelt) war es, repräsentative Untersuchungsstrategien für die Detektion von Mikroplastik mittels TED GC/MS in wässerigen Medien zu ermitteln. Dabei wurden verschiedene Probenahmekonzepte und -verfahren für unterschiedliche Fallgestaltungen und Fragestellungen untersucht, sowie neue Filtersysteme entwickelt. Bei der Detektion der Partikel lag der Fokus auf der Anwendung und Weiterentwicklung der ThermoExtraktion/Desorption-Gaschromatographie-Massenspektrometrie (TED-GC/MS) zur Bestimmung von Mikroplastikgehalten. Anwendung fanden die Methoden bei der Beprobung von Flaschenwasser, Waschmaschinenabläufen, dem urbanen Abwassersystem der Stadt Kaiserslautern, sowie in Oberflächengewässern. © AuthorsVeröffentlichung Smart filters for the analysis of microplastic in beverages filled in plastic bottles(2021) Braun, Ulrike; Altmann, Korinna; Herper, DominikThe occurrence of microplastic (MP) in food products, such as beverages in plastic bottles, is of high public concern. Existing analytical methods focus on the determination of particle numbers, requiring elaborate sampling tools, laboratory infrastructure and generally time-consuming imaging detection methods. A comprehensive routine analysis of MP in food products is still not possible. In the present work, we present the development of a smart filter crucible as sampling and detection tool. After filtration and drying of the filtered-off solids, a direct determination of the MP mass content from the crucible sample can be done by thermal extraction desorption gas chromatography mass spectroscopy (TED-GC/MS). The new filter crucible allows a filtration of MP down to particle sizes of 5 (micro)m. We determined MP contents below 0.01 (micro)g/L up to 2 (micro)g/L, depending on beverages bottle type. This may be directly related to the bottle type, especially the quality of the plastic material of the screw cap. Dependent on the plastic material, particle formation increases due to opening and closing operations during the use phase. However, we have also found that some individual determinations of samples were subjected to high errors due to random events. A conclusive quantitative evaluation of the products is therefore not possible at present. © Taylor&Francis OnlineVeröffentlichung Statuspapier Mikroplastikanalytik - Zusammenstellung wesentlicher Untersuchungsverfahren zur Probenahme, Aufbereitung und Detektion von Mikroplastik(2021) Braun, Ulrike; Stein, Ulf; Schritt, HannesUnter Mikroplastik sind Partikel, hauptsächlich bestehend aus synthetischen Polymeren, in der Dimension von 1-1000 (micro)m zu verstehen. Sie sind mittlerweile in der Umwelt allgegenwärtig, z.B. in Gewässern, Böden, Sedimenten und Luft, aber auch in Abwässern, Klärschlamm, Kompost und Lebensmitteln. In Umweltproben lassen sich in der Regel wenig große Partikel und sehr viele kleine Partikel von sehr unterschiedlicher Gestalt und chemischer Zusammensetzung identifizieren. Das macht ihre systematische Erfassung vergleichsweise aufwändig, sodass es eines guten Zusammenspiels verschiedener Verfahren bedarf. Obwohl die Charakterisierung von Plastik und von Partikeln seit Jahren etabliert ist, ist das Feld der Mikroplastikanalytik vergleichsweise jung. Daher müssen viele Verfahren erst noch hinsichtlich ihrer Eignung validiert werden. Es bestehen derzeit noch keine harmonisierten Protokolle. Das Statuspapier Mikroplastikanalytik fasst die Ergebnisse der Verbundprojekt-übergreifenden Diskussionen und Abstimmungen innerhalb des BMBF Forschungsschwerpunkts "Plastik in der Umwelt" zusammen. Es ist auf der Webseite des Forschungsschwerpunkts (https://www.bmbf-plastik.de/ index.php/de/publikationen) in deutscher und englischer Sprache zur Verfügung gestellt. © AuthorsVeröffentlichung Microplastic analysis using chemical extraction followed by LC-UV analysis: a straightforward approach to determine PET content in environmental samples(2020) Müller, Axel; Goedecke, Caroline; Eisentraut, Paul; Braun, UlrikeBackground The ubiquitous occurrence of microplastic particles in marine and aquatic ecosystems was intensively investigated in the past decade. However, we know less about the presence, fate, and input paths of microplastic in terrestrial ecosystems. A possible entry path for microplastic into terrestrial ecosystems is the agricultural application of sewage sludge and solid bio-waste as fertilizers. Microplastic contained in sewage sludge also includes polyethylene terephthalate (PET), which could originate as fiber from textile products or as a fragment from packaging products (foils, bottles, etc.). Information about microplastic content in such environmental samples is limited yet, as most of the used analytical methods are very time-consuming, regarding sample preparation and detection, require sophisticated analytical tools and eventually need high user knowledge. Results Here, we present a simple, specific tool for the analysis of PET microplastic particles based on alkaline extraction of PET from the environmental matrix and subsequent determination of the monomers, terephthalic acid, using liquid chromatography with UV detection (LC-UV). The applicability of the method is shown for different types of PET in several soil-related, terrestrial environmental samples, e.g., soil, sediment, compost, fermentation residues, but also sewage sludge, suspended particles from urban water management systems, and indoor dust. Recoveries for model samples are between 94.5 and 107.1%. Limit of determination and limit of quantification are absolute masses of 0.031 and 0.121 mg PET, respectively. In order to verify the measured mass contents of the environmental samples, a method comparison with thermal extraction-desorption-gas chromatography-mass spectrometry (TED-GC/MS) was conducted. Both methods deliver similar results and corroborated each other. PET mass contents in environmental samples range from values below LOQ in agriculture soil up to 57,000 mg kg-1 in dust samples. Conclusions We demonstrate the potential of an integral method based on chemical extraction for the determination of PET mass contents in solid environmental samples. The method was successfully applied to various matrices and may serve as an analytical tool for further investigations of PET-based microplastic in terrestrial ecosystems. © The Author(s) 2020