Person: Claßen, Daniela
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Veröffentlichung Formation, classification and identification of non-extractable residues of 14C-labelled ionic compounds in soil(2019) Claßen, Daniela; Siedt, Martin; Nguyen, Kim Thu; Ackermann, JulianeThe influence of an ionic functional group on the fate of chemicals in the environment, especially the formation of non-extractable residues (NER), has not been systematically investigated. Using 4-n-dodecylphenol[phenylring-14C(U)], 4-n-dodecylbenzenesulfonicacid[phenylring-14C(U)] sodiumsalt (14C-DS-) and 4-n-dodecylbenzyltrimethylammoniumchloride[phenylring-14C(U)] (14C-DA+) all with a high structural similarity, the formation, classification and identification of NER of negatively (14C-DS-), positively (14C-DA+) and uncharged (14C-DP) chemicals were investigated in a sterilized and non-sterilized soil. After 84 days of incubation in non-sterile soil, 40.6%, 21.7% and 33.5% of the applied radioactivity (AR) of 14C-DP, 14C-DS- and 14C-DA+, respectively, were converted to NER. In contrast, in sterile soil NER formation was markedly lower. The NER were further investigated with respect to sequestered, covalently bound and biogenic residues (i.e. NER types I, II, and III). Silylation of 14C-DP, 14C-DS- and 14C-DA+ derived NER released 3.0-23.2% AR, indicating that these were sequestered, whereas the residual NER (12.9-33.1% AR) was covalently bound to the soil. Analysis of extracts derived by silylation showed that 14C-DP, but neither 14C-DS- nor 14C-DA+, were released by silylation, suggesting that DP might be part of the sequestered NER. Acid hydrolysis of the NER containing soil and subsequent analysis of soil extracts for 14C-aminoacids indicated that 2.5-23.8% AR were biogenic residues. Most DP and DS- derived NER were biogenically or covalently bound, whereas DA+ predominantly forms sequestered NER in soil. From these results we propose that chemicals forming high amounts of NER should be investigated regarding types I-III NER because sequestered parent compounds should be considered in persistence assessments. © 2019 The Authors. Published by Elsevier Ltd.Veröffentlichung Fate of 14C-labelled ionic organic chemicals in a water-sediment system and surface water(2022) Holzmann, Hannah; Ackermann, Juliane; Claßen, DanielaThe persistence assessment of organic chemicals is based on neutral reference substances. Therefore, our study aimed at investigating the influence of a chemical charge on the degradation of organic compounds in a water-sediment system (OECD 308) and surface water (OECD 309). We used radiolabelled 4-n-dodecylbenzenesulfonic acid sodium salt (14C-DS-, anionic), 4-n-dodecylbenzyltrimethylammonium chloride (14C-DA+, cationic) and 4-n-dodecylphenol (14C-DP, non-ionic) which are structurally similar except their charges. After 120 days of incubation in a water-sediment system, 68% (14C-DS-), 6% (14C-DA+) and 63% (14C-DP) of the applied radioactivity (AR) were mineralized. The formation of non-extractable residues (NER) after 120 days was highest for 14C-DA+ (33% AR), followed by 14C-DS- (19% AR) and 14C-DP (14% AR). Dissipation half-lives (DT50) at 12 ˚C decreased as follows: 14C-DA+ (346 days) >> 14C-DS- (47 days) > 14C-DP (30 days). After 60 days of incubation in surface water with suspended sediment, mineralization of 14C-DS-, 14C-DA+ and 14C-DP accounted for 63%, 7% and 58% AR, respectively. Highest NER formation was observed for 14C-DP (21% AR), followed by 14C-DA+ (14% AR) and 14C-DS- (9% AR). DT50 (12 ˚C) decreased as follows: 14C-DA+ (45 days) > 14C-DP (3 days) > 14C-DS- (2 days). We showed that a positive charge reduces the degradability of organic chemicals in both test systems. From a scientific point of view, simulation studies following OECD 309 should always be complimented by tests with high sorption capacity, e.g. OECD 308 and OECD 307 tests in order to assess the degradation of a compound, especially in case of cationic organic compounds. © 2022 The AuthorsVeröffentlichung Bewertung persistenter, bioakkumulierender und toxischer Eigenschaften von ionischen und ionisierbaren Stoffen(2016) Ackermann, Juliane; Brendel, Stephan; Claßen, DanielaVeröffentlichung Fate and behavior of 14C-labelled ionic compounds in a soil simulation test(2021) Ackermann, Juliane; Claßen, Daniela; Schäffer, AndreasThe influence of an ionic functional group on the fate and behavior of chemicals in the environment has so far not been systematically investigated. This study, therefore, examines the following three substances with high structural similarity but differing charge: non-charged 4-n-dodecylphenol[phenylring-14C(U)] (14C-DP), negatively charged 4-n-dodecylbenzenesulfonicacid[phenylring-14C(U)] sodium salt (14C-D-) and positively charged 4-n-dodecylbenzyltrimethylammonium chloride[phenylring-14C(U)] (14C-DA+). They were investigated in a soil simulation study according to the OECD 307 test guideline by measuring the distribution of the applied radioactivity (AR) among volatile, mineralized, extractable and non-extractable residues (NER) in one soil after 0, 1, 7, 14, 49, 84 and 124 days of incubation. Extractable portions of 14C were examined by means of radio-TLC and -HPLC analyses. Microbial activity of the soil incubated with and without 14C-DP, 14C-DS- and 14C-DA+ was determined measuring the reduction of dimethylsulfoxide (DMSO) over time. After 124 days of incubation highest mineralization could be observed for 14C-DS- (64.5% AR). Except CO2, no volatile residues were formed over time. Besides the parent compounds, polar (14C-DP, 14C-DS- and 14C-DA+) and nonpolar (14C-DA+) transformation products were detected. Highest amounts of 14C were extracted using methanol and were thus potentially bioavailable for soil microorganisms. Microbial activity was markedly higher in soil incubated with 14C-DP and 14C-DS- compared to 14C-DA+ or soil without any treatment. Half-lives (DT50 k2) at 18 ËÌC were as follows: DA+ (61.8 days) > DS- (18.2 days) > DP (10.0 days). In case of the cationic compound and its transformation products we conclude that a higher sorption affinity to soil particles leads to reduced bioavailability for microorganisms and thus reduced mineralization resulting in a higher persistence compared to anionic and non-charged organic compounds in soil. The impact of our findings on the persistence assessment of chemicals when performing OECD guideline tests in soil, water-sediment and surface water is discussed. © 2021 Published by Elsevier B.V.Veröffentlichung Assessment of contaminants of emerging concern in European apex predators and their prey by LC-QToF MS wide-scope target analysis(2022) Gkotsis, Georgios; Badry, Alexander; Nika, Maria-Christina; Claßen, Daniela; Nikolopoulou, Varvara; Drost, Wiebke; Koschorreck, Jan; Treu, GabrieleApex predators are good indicators of environmental pollution since they are relatively long-lived and their high trophic position and spatiotemporal exposure to chemicals provides insights into the persistent, bioaccumulative and toxic (PBT) properties of chemicals. Although monitoring data from apex predators can considerably support chemicalsâ€Ì management, there is a lack of pan-European studies, and longer-term monitoring of chemicals in organisms from higher trophic levels. The present study investigated the occurrence of contaminants of emerging concern (CECs) in 67 freshwater, marine and terrestrial apex predators and in freshwater and marine prey, gathered from four European countries. Generic sample preparation protocols for the extraction of CECs with a broad range of physicochemical properties and the purification of the extracts were used. The analysis was performed utilizing liquid (LC) chromatography coupled to high resolution mass spectrometry (HRMS), while the acquired chromatograms were screened for the presence of more than 2,200 CECs through wide-scope target analysis. In total, 145 CECs were determined in the apex predator and their prey samples belonging in different categories, such as pharmaceuticals, plant protection products, per- and polyfluoroalkyl substances, their metabolites and transformation products. Higher concentration levels were measured in predators compared to prey, suggesting that biomagnification of chemicals through the food chain occurs. The compounds were prioritized for further regulatory risk assessment based on their frequency of detection and their concentration levels. The majority of the prioritized CECs were lipophilic, although the presence of more polar contaminants should not be neglected. This indicates that holistic analytical approaches are required to fully characterize the chemical universe of biota samples. Therefore, the present survey is an attempt to systematically investigate the presence of thousands of chemicals at a European level, aiming to use these data for better chemicals management and contribute to EU Zero Pollution Ambition. © 2022 The Authors.Veröffentlichung The importance of in-year seasonal fluctuations for biomonitoring of apex predators: A case study of 14 essential and non-essential elements in the liver of the common buzzard (Buteo buteo) in the United Kingdom(2023) Ozaki, Shinji; Badry, Alexander; Movalli, Paola; Cincinelli, Alessandra; Claßen, Daniela; Koschorreck, Jan; Treu, GabrieleTrace elements are chemical contaminants spread in the environment by anthropogenic activities and threaten wildlife and human health. Many studies have investigated this contamination in apex raptors as sentinel birds. However, there is limited data for long-term biomonitoring of multiple trace elements in raptors. In the present study, we measured the concentrations of 14 essential and non-essential trace elements in the livers of the common buzzard (Buteo buteo) collected in the United Kingdom from 2001 to 2019 and investigated whether concentrations have changed during this period. In addition, we estimated the importance of selected variables for modelling element accumulations in tissues. Except for cadmium, hepatic concentrations of harmful elements in most buzzards were lower than the biological significance level of each element. Hepatic concentrations of certain elements, including lead, cadmium, and arsenic, varied markedly seasonally within years. Their peak was in late winter and trough in late summer, except copper which showed an opposite seasonal pattern. In addition, lead in the liver consistently increased over time, whereas strontium showed a decreasing trend. Hepatic concentrations of cadmium, mercury, and chromium increased with age, whereas selenium and chromium were influenced by sex. Hepatic concentrations of arsenic and chromium also differed between different regions. Overall, our samples showed a low risk of harmful effects of most elements compared to the thresholds reported in the literature. Seasonal fluctuation was an important descriptor of exposure, which might be related to the diet of the buzzard, the ecology of their prey, and human activities such as the use of lead shot for hunting. However, elucidating reasons for these observed trends needs further examination, and biomonitoring studies exploring the effects of variables such as age, sex, and seasonality are required. © 2023 The Authors.Veröffentlichung Silylation: a reproducible method for characterization of non-extractable residues (NER) of organic chemicals in the assessment of persistence(2023) Hennecke, Dieter; Kruse, Mike; Claßen, Daniela; Bräutigam, JoanaMost, if not all, chemicals, biocides, pharmaceuticals and pesticides are known to produce non-extractable residues (NER) in solid environmental media like soil and sediment during degradation testing to various extents. Since it has been found that parent substances and relevant metabolites can be contained and potentially released from NER there is currently much debate on how to include NER in the environmental persistence assessment. Using radioactive or stable isotope labelled test substances, three types of NER can be experimentally discriminated: entrapped, sorbed or heavily sorbed (type I) having the potential to be released from the matrix. Type II NER, i.e. residues covalently bound to organic matter in soils or sediments, are being considered to have very low remobilisation potential. Type III NER (bioNER) are formed after degradation of the xenobiotic chemical and incorporation into natural biomolecules (anabolism) like amino acids and other biomass compounds, and are, thus, of no environmental concern. Silylation has been suggested as a methodology to differentiate types I and II NER but concern has been addressed that this procedure is not suitable for routine analysis, e.g. in the context of studies for authorisation and registration of chemicals. Here, we describe a readily applicable and reproducible experimental procedure to apply this method for the analysis of NER derived from bromoxynil, sulfadiazine and isoproturon, respectively. This method is able to distinguish between heavily sorbed and covalently bound residues of chemicals, biocides, pharmaceuticals and pesticides in soils and to subsequently identify residues of the parent substance entrapped in type I NER. © 2023 The Author(s). Published by the Royal Society of ChemistryVeröffentlichung Using environmental monitoring data from apex predators for chemicals management: towards better use of monitoring data from apex predators in support of prioritisation and risk assessment of chemicals in Europe(2022) Slobodnik, Jaroslav; Badry, Alexander; Alygizakis, Nikiforos A.; Claßen, Daniela; Koschorreck, Jan; Treu, GabrieleA large number of apex predator samples are available in European research collections, environmental specimen banks and natural history museums that could be used in chemical monitoring and regulation. Apex predators bioaccumulate pollutants and integrate contaminant exposure over large spatial and temporal scales, thus providing key information for risk assessments. Still, present assessment practices under the different European chemical legislations hardly use existing chemical monitoring data from top predators. Reasons include the lack of user-specific guidance and the fragmentation of data across time and space. The European LIFE APEX project used existing sample collections and applied state-of-the-art target and non-target screening methods, resulting in the detection of>4,560 pollutants including legacy compounds. We recommend establishing infrastructures that include apex predators as an early warning system in Europe. Chemical data of apex species from freshwater, marine and terrestrial compartments should become an essential component in future chemical assessment and management across regulations, with the purpose to (1) validate registration data with ââą Ìreal worldââą Ì measurements and evaluate the predictability of current models; (2) identify and prioritise hazardous chemicals for further assessment; (3) use data on food web magnification as one line of evidence to assess biomagnification; (4) determine the presence of (bio)transformations products and typical chemical mixtures, and (5) evaluate the effectiveness of risk management measures by trend analysis. We highlight the achievements of LIFE APEX with regard to novel trend and mixture analysis tools and prioritisation schemes. The proposed advancements complement current premarketing regulatory assessments and will allow the detection of contaminants of emerging concern at an early stage, trigger risk management measures and evaluations of their effects with the ultimate goal to protect humans and the environment. This is the second policy brief of the LIFE APEX project. © The Author(s) 2022Veröffentlichung Using environmental monitoring data from apex predators for chemicals management: towards harmonised sampling and processing of archived wildlife samples to increase the regulatory uptake of monitoring data in chemicals management(2022) Slobodnik, Jaroslav; Badry, Alexander; Alygizakis, Nikiforos A.; Claßen, Daniela; Koschorreck, Jan; Treu, GabrieleMonitoring data from apex predators were key drivers in the development of early chemicals legislations due to the population declines of many species during the twentieth century, which was linked to certain persistent organic pollutants (POPs). Besides triggering the development of global treaties (e.g. the Stockholm Convention), chemical monitoring data from apex predators have been particularly important for identifying compounds with bioaccumulative properties under field conditions. Many apex predators are protected species and only a few environmental specimen banks (ESBs) regularly collect samples as many ESBs were established during the 1980-1990s when apex predators were scarce. Today, many POPs have been banned, which contributed to the recovery of many apex predator populations. As a consequence, apex predator samples are now available in research collections (RCs) and natural history museums (NHMs). These samples can be used for routine analysis as well as for screening studies using novel analytical techniques and advanced data treatment workflows, such as suspect and non-target screening. The LIFE APEX project has demonstrated how these samples can be used in a cost-efficient way to generate data on legacy compounds and contaminants of emerging concern. Furthermore, it has described quality assurance/control measures to ensure high quality and comparable data, with a view to uses in chemicals risk assessment and management. To increase the visibility of available sample collections and monitoring data from apex predators we developed accessible online database systems. Additionally, the acquired high-resolution mass spectrometric data were stored in a digital sample freezing platform that allows retrospective suspect screening in previously analysed samples for substances that may be of concern/under assessment in the future. These databases provide open access to a wide range of chemical data, for use by regulators, researchers, industry and the general public, and contribute to a stronger link between science and policy. © The Author(s) 2022