Auflistung nach Autor:in "Junker, Thomas"

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    Development and ring test of quality assessment schemes for data on fate, ecotoxicity, and bioconcentration in fish
    (2016) Konradi, Sabine; Maack, Gerd; Koch, Wolfgang; Duis, Karen; Junker, Thomas
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    Development of a test method for transformation of veterinary pharmaceuticals and biocides in anaerobic liquid manure
    (2020) Junker, Thomas; Atorf, Cornelia; Berkner, Silvia; Konradi, Sabine
    Background Spreading of manure on agricultural soils represents an important pathway by which veterinary medicinal and biocidal products enter the environment. To assess their environmental impact in the context of authorization processes, experimental testing of transformation of these compounds in manure is considered in regulatory guidance documents. However, there is no standardized experimental test method available so far. To fill this gap, an experimental test method was developed to examine transformation in liquid cattle and pig manure. Results To account for manure specifics and for a possible influence of manure parameters on transformation rates, a comprehensive data acquisition and statistical analysis were performed. To address the variability of liquid manure of different type and origin, 30 manures were sampled and characterized. Thereof, three cattle and three pig manures were selected to perform anaerobic transformation studies with two radiolabeled veterinary medicinal active substances (14C-salicylic acid and 14C-paracetamol) and a confidential radiolabeled "14C-biocide B" serving as test compounds. Spatial and seasonal variability of manure parameters was quantified, and a sampling technique to obtain homogenous manure samples was developed. Transformation studies with six replicates per sampling point were conducted to examine the influence of test setup, of manure storage conditions, and of parameter variations between manure of the same species and of different species on half-lives, formation of extractable and non-extractable residues and mineralization rates. Finally, a test design was established that yields reproducible results for transformation studies in liquid cattle and pig manure under anaerobic conditions. Conclusions Results give a reliable basis for an experimental test method to perform anaerobic transformation studies in liquid cattle and pig manure. The developed test method comprises detailed guidance on selection of sampling date and site, collection from manure tank, storage duration and temperature in the laboratory, duration of manure acclimation period, and the incubation system design. It proved to give reproducible results in a validation ring test performed in a follow-up project and is planned to be submitted as draft test guideline for approval by the OECD. © The Author(s) 2020.
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    Harmonization of environmental exposure assessment for veterinary pharmaceuticals and bio-cides
    (2016) Herrchen, Monika; Hennecke, Dieter; Junker, Thomas; Fraunhofer-Institut für Molekularbiologie und Angewandte Oekologie; ECT Oekotoxikologie GmbH (Flörsheim am Main); Deutschland. Umweltbundesamt; Berkner, Silvia; Konradi, Sabine
    The spread of veterinary medicinal products (VMP) and biocides onto agriculturally used areas represents a very important path of entry into the environment for these product groups. For this reason, current guidance (e.g. „Guideline on determining the fate of veterinary medicinal products in manure“ (EMA/CVMP/ERA/430327/2009) (EMA, 2011) stipulates experimental studies on transformation of VMPs and biocides in manure. However, the documents only contain basic regulatory requirements, whereas an experimental test guideline is still missing, both on EU and ⁠OECD⁠ level. To allow for a consistent assessment of studies within the registration process, a harmonized internationally accepted and validated test method is needed.A draft test guideline was developed within a previous R&D-Project “Development of test guidance for transformation of veterinary pharmaceuticals and biocides in liquid manure” (FKZ 3710 67 422) (Hennecke et al., 2015). The experimental method was examined and revised by an intra-laboratory comparison as well as an international inter-laboratory comparison (pre-validation ring test).In the present project, an international ring test has been performed and evaluated testing a veterinary medicinal product (florfenicol) in pig manure and a biocide (imidacloprid) in cattle manure. Moreover, two international workshops were organized; one at the beginning in connection with proceeding project (FKZ 3710 67 422) and one at the end of the project to discuss and evaluate the ring test. Based on the experimental results of the ring test as well as discussions and conclusions of both workshops, a revised draft test guideline was prepared.
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    Harmonization of environmental exposure assessment for veterinary pharmaceuticals and biocides
    (2016) Düring, Rolf-Alexander; Wohde, Manuel; Junker, Thomas; ECT Oekotoxikologie GmbH (Flörsheim am Main); Fraunhofer-Institut für Molekularbiologie und Angewandte Oekologie; Deutschland. Umweltbundesamt; Berkner, Silvia; Konradi, Sabine
    The spread of veterinary medicinal products (VMPs) and biocides onto agriculturally used areas represents a very important path of entry into the environment for these product groups. Within this literature study public available transformation studies with liquid manure are summarized. Transformation studies were evaluated considering the transformation fate of tested substances, the origin and characteristics of used manure, the experimental setup, the measured parameters and the main outcome of the studies. Test duration throughout the studies ranges from 2 to 374 days and study temperature ranges from 5 °C to 55 °C. As main topics within the 34 found transformation studies the high dependency of transformation on temperature, redox potential, dry matter content and many other parameters is reported. It was further critically analyzed which basic information and parameters were neglected. Unfortunately only six publications give information on the redox potential of the manure. Further, the characterization of the matrix in many cases is inadequate due to missing parameters such as dry matter content, pH, and TOC.Additionally, public available monitoring data of VMPs in manure were collected and evaluated regarding the origin and characteristics of the manure, the minimum and maximum found concentrations, and percentage of identified compounds. Within the 27 found publications, 1568 manure samples were analyzed and 39 different active substances for VMPs and 11 metabolites and transformation products of VMPs could be found in manure. Mainly, the samples were analyzed for sulfonamides, tetracyclines and fluorquinolones. In no case a non-target approach was used. Single active substances were found in some studies with more than 100 analyzed samples in more than 50 % of the analyzed manure samples. This is the case for sulfadimidine, chlortetracycline, oxytetracycline, and tetracycline. It can be concluded that for both transformation studies and monitoring studies a standardized guidance would be beneficial for their applicability in regulatory contexts and also enhance the scientific outcome of these studies.
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    Veröffentlichung
    Harmonization of environmental exposure assessment for veterinary pharmaceuticals and biocides
    (2016) Junker, Thomas; Römbke, Jörg; Hennecke, Dieter; ECT Oekotoxikologie GmbH (Flörsheim am Main); Fraunhofer-Institut für Molekularbiologie und Angewandte Oekologie; Deutschland. Umweltbundesamt; Berkner, Silvia; Konradi, Sabine
    The spread of veterinary medicinal products (VMP) and biocides onto agriculturally used areas repre-sents a very important path of entry into the environment for these product groups. For this reason, current guidance (e.g. „Guideline on determining the fate of veterinary medicinal products in ma-nure“ (EMA/CVMP/ERA/430327/2009) (EMA, 2011) stipulates experimental studies on transfor-mation of VMPs and biocides in manure. Though, the documents only contain basic regulatory re-quirements, whereas an experimental test guideline is still missing, both on EU and ⁠OECD⁠ level. To allow for a consistent assessment of studies within the registration process, a harmonized interna-tionally accepted and validated test method is needed.A draft test guideline was developed within a previous R&D-Project “Development of test guidance for transformation of veterinary pharmaceuticals and biocides in liquid manure” (Hennecke et al., 2015). The experimental method was examined and revised by an intra-laboratory comparisons as well as an international inter-laboratory comparison (pre-validation ring test).In the present project, an international ring test has been performed and evaluated testing a veteri-nary medicinal product (florfenicol) in pig manure and a biocide (imidacloprid) in cattle manure. Moreover, two international workshops were organized; one at the beginning in connection with pre-ceding project (Hennecke et al., 2015) and one at the end of the project to discuss and evaluate the ring test. Based on the experimental results of the ring test as well as discussions and conclusions of both workshops, a revised draft test guideline was prepared.