Auflistung nach Autor:in "Radermacher, Georg"

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A field study in support of the monitoring of priority substances in German freshwater fish: derivation of fillet-to-whole fish conversion factors
(2020) Rüdel, Heinz; Duffek, Anja; Radermacher, Georg; Fliedner, Annette
Background
Bioaccumulating contaminants in surface waters are preferably monitored in fish for assessing the related risks to and via the aquatic environment. Consequently, the European Water Framework Directive (WFD) requires a monitoring of certain priority substances such as mercury, polybrominated diphenyl ethers (PBDE), perfluorooctane sulfonic acid and its derivatives (PFOS), hexachlorobenzene (HCB), hexabromocyclododecanes (HBCDD) and polychlorinated dioxins/dioxin-like compounds (dioxins) in freshwater and coastal fish. Tissue levels have to comply with biota environmental quality standards (EQSs) given in Directive 2013/39/EU. EQSs are justified either by risks for human health (assessed on the basis of fillet) or secondary poisoning of wildlife (based on whole fish). To support the practical implementation of the WFD biota monitoring in Germany, comparative investigations of target fish species caught at six sites were performed.
Results
At each site, at least three fish species listed in a national guidance document were sampled (e.g., chub, roach, bream, perch). Beside biometric data, concentrations of seven priority substances were determined in pooled fillet and carcass samples and whole fish data were calculated. The EQSs for PBDE and mercury were exceeded in nearly all fillet and whole fish samples. PFOS was above the EQS at several sites especially in perch, while HCB exceeded the EQS only at one site (Elbe River). All fillet and whole fish samples complied with the EQSs for dioxins and HBCDD. Based on wet weight concentrations of a homogeneous set of 20 composite sample pairs of 3â€Ì5 year-old fish, the following fillet-to-whole fish conversion factors were derived: mercury 0.81, PBDE 5.4, HCB 3.6, PFOS 2.7, dioxins 5.3, and HBCDD 1.8.
Conclusions
Recommendations on selection of target fish species, age or tissue given by EU and national guidance documents are practical and feasible. However, further adjustments of the samplings such as the determination of site-specific length-age relationships are required from both ecological and risk assessment perspectives. The derived conversion factors allow the translation of fillet-to-whole fish concentrations (and vice versa), and thus the EQS compliance assessment for the appropriate tissue (fillet for human health, whole fish for wildlife risks) if only one tissue is investigated. Quelle: https://link.springer.com
Fish contaminant monitoring
(2019) Bandow, Nicole; Rüdel, Heinz; Radermacher, Georg; Duffek, Anja
Konzept zur Implementierung der neuen Umweltqualitätsnormen für prioritäre Stoffe in Fischen (Richtlinie 2013/39/EU)
(2019) Radermacher, Georg; Fliedner, Annette; Rüdel, Heinz; Fraunhofer-Institut für Molekularbiologie und Angewandte Oekologie; Duffek, Anja
Im Rahmen dieses Forschungsvorhabens wurden Untersuchungen durchgeführt, um Grundlagen für ein geeignetes Konzept zur Überwachung von prioritären Stoffen in Fischen zu erarbeiten, das den Anforderungen der Wasserrahmenrichtlinie (WRRL) genügt und dabei die verschiedenen Ziele des Gewässermonitorings, insbesondere die Überwachung von Umweltqualitätsnormen (UQN) sowie das Trendmonitoring, integriert. Dazu wurden an sechs Standorten in Oberflächengewässern jeweils ca. 20 Fische von jeweils drei unterschiedlichen Fischspezies beprobt, biometrische Daten erfasst (z.B. Gewicht, Länge, Alter) und Mischproben von Filet und Restfisch getrennt auf prioritäre Stoffe untersucht. Aus den Messdaten wurden die Konzentrationen der prioritären Stoffe im Ganzfisch berechnet. Bei der Projektbearbeitung wurden die Hinweise des Arbeitspapiers IV.3 zur Rahmenkonzeption Monitoring (RAKON) der LAWA (Bund/Länder-Arbeitsgemeinschaft Wasser) berücksichtigt und geprüft, inwieweit das empfohlene Vorgehen an den Standorten umsetzbar war. Auf Basis der Untersuchungsergebnisse wurden Empfehlungen für die Umsetzung des WRRL-Biotamonitorings abgeleitet. Da das Routine-Gewässermonitoring Aufgabe der Bundesländer ist, wurden Aspekte der praktischen Umsetzung mit den zuständigen Kolleginnen und Kollegen aus Einrichtungen der Bundesländer im Rahmen von zwei Fachgesprächen diskutiert. Quelle: Forschungsbericht
Retrospective analysis of cyclic volatile methylsiloxanes in archived German fish samples covering a period of two decades
(2020) Radermacher, Georg; Böhnhardt, Anna; Rüdel, Heinz; Koschorreck, Jan; Wesch, Charlotte
Cyclic volatile methylsiloxanes (cVMS) are widely applied chemicals used as intermediates in the production of silicon polymers or as ingredients in personal care products. cVMS are under scrutiny due to their environmental properties and their potential for long-range atmospheric transport, persistence and food web magnification. In 2018, the cVMS octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) were identified as Substances of Very High Concern (SVHC) under the European REACH regulation. To obtain current data on the presence of cVMS in German waters, the spatial and temporal occurrence of D4, D5 and D6 in fillets of bream from major rivers archived in the German Environmental Specimen Bank (ESB) was analyzed with a GC-ICP-MS/MS coupling method. The spatial comparison of 17 sites for the year 2017 revealed that highest cVMS burdens occurred in samples from the Saar river (near to the French/German border). cVMS levels in fish from a lake in northern Germany did not exceed the limits of detection. For selected sites, time series covering the period from 1995 to 2017 were investigated. In most years D5 concentrations in fish were clearly higher than the observed D4 and D6 concentrations. Overall maximum D4 and D5 concentrations (about 320 and 7600 ng gâ Ì1 wet weight, respectively) were found at one Saar site in 2009. In three of five analyzed time series D5 concentrations peaked 2007â€Ì2011. In recent years, cVMS levels in fish decreased at almost all sites. To allow an assessment of the relevance of the detected cVMS fish concentrations these were compared to environmental quality standards (EQS) for D4 and D5 which were recently enacted in the context of the Swedish implementation of the European Water Framework Directive (WFD). The D5 EQS in fish was exceeded at four sites in several years in the investigated period and in the Saar even till 2017.
Seasonal variability in metal and metalloid burdens of mussels: using data from the German Environmental Specimen Bank to evaluate implications for long-term mussel monitoring programs
(2020) Knopf, Burkhard; Fliedner, Annette; Radermacher, Georg; Koschorreck, Jan
Background Metal and metalloid concentrations in mussels can vary between seasons. In biota monitoring, the sampling time is therefore an important issue. Within the German Environmental Specimen Bank (ESB) program blue mussels (Mytilus edulis Complex) are sampled regularly since the 1980s. The samples are collected in two-monthly intervals at two North Sea sites and in 6-month intervals at one Baltic Sea site. All samples from one site and year are combined to annual composite samples and archived as sub-samples under cryogenic conditions. In order to investigate a possible reduction of the number of annual sampling intervals while maintaining comparability with the long-term composite sample data, the seasonal variability of metals/metalloids was analyzed based on the half-yearly and bimonthly samples of 2013, 2015 and 2017. Results In mussels from the North Sea site Eckwarderhoerne seasonality of metals/metalloids was comparable in all 3 years (arsenic being the only exception). At the North Sea site Koenigshafen seasonality of cobalt, nickel, cadmium, copper, lead, and arsenic was comparable in 2013 and 2015 but not in 2017, while selenium showed the same seasonality in all 3 years. Within 1 year, concentrations of metals and metalloids can vary by the same order of magnitude as observed between annual composite samples of different years making it impossible to select just one representative sampling time point per year that would provide the same information as the respective annual composite sample. Conclusions The findings highlight the importance of carefully selecting the sampling time point when using mussels in biota monitoring. For the German ESB program it is recommended to continue with the current sampling strategy and analyze annual composite samples in order to maintain comparability with the long-term data series, which are a special feature of the ESB. © The Author(s) 2020
Tissue concentrations of per- and polyfluoroalkyl substances (PFAS) in German freshwater fish: derivation of fillet-to-whole fish conversion factors and assessment of potential risks
(2022) Rüdel, Heinz; Duffek, Anja; Radermacher, Georg; Fliedner, Annette; Koschorreck, Jan
The European Water Framework Directive requires monitoring of bioaccumulative contaminants in fish to assess risks to human health by fish consumption and wildlife by secondary poisoning of predators. The list of priority substances for which environmental quality standards (EQSs) have been derived covers also perfluorooctane sulfonic acid (PFOS). No EQSs have yet been set for other per- and polyfluoroalkyl substances (PFAS) that are frequently detected in fish and of which some have a non-negligible risk potential compared to PFOS. As a case study, burdens for a set of PFAS were investigated for different fish species from five German freshwater sites and a Baltic Sea lagoon. PFAS concentrations were determined for composite samples of both, fillet and whole fish. On average, sum concentrations of C9-C14 perfluoroalkyl carboxylic acids, which will be banned in the European Union in 2023, reached 87% and 82% of the PFOS burdens in fillet and whole fish, respectively. The potential risk of several PFAS other than PFOS was assessed using a previously suggested relative potency factor approach, which is also applied for a proposed EQS revision. Only five of 36 fillet samples (mostly perch) exceeded the current EQS for PFOS alone. By contrast, all fillet samples exceeded the newly proposed draft EQS, which considers potential effects of further PFAS but also a lower tolerable intake value. Additionally, the dataset was used to derive fillet-to-whole fish conversion factors, which can be applied to assess human health risks by consumption of fillet if only whole fish concentrations are available. © 2021 The Authors