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Veröffentlichung 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, CharlotteCyclic 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.Veröffentlichung 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, AnnetteBackground
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.comVeröffentlichung 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, JanThe 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