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Veröffentlichung Suitable test substances for proof of concept regarding infochemical effects in surface waters(2013) Nendza, Monika; Berghahn, Rüdiger; Klaschka, UrsulaBackground
Infochemical effects have been defined as the manipulation of the odour perception of organisms by anthropogenic substances which may result in ecologically relevant behavioural disorder. However, the environmental relevance of infochemical effects has not yet been confirmed by experimental observations. This project aims to test for infochemical effects on chemical communication in water bodies with systematic experimental investigations. The first crucial step is to select suitable test substances. Repellents (PT 19 biocides) and odourants may be assumed to affect the response of aquatic populations and communities. These mostly polar and stable compounds may disturb chemical communication between organisms and may cause organismic effects like drift (downstream dislocation of e.g. crustacean and insect larvae in streams). Repellents enter surface waters mainly indirectly via wastewater discharges from sewage treatment plants or directly by being washed off from the skin and clothes of bathers.Results
In this literature study, suitable chemicals were selected for confirmatory assessments of suspected infochemical effects by laboratory tests in a subsequent second part of the project. The use pattern and physico-chemical properties of the substances selected, in combination with their limited biological degradability, indicate potential aquatic relevance with possible chronic impact caused by disturbed communication. After due consideration of advantages and limitations, three PT 19 repellents appear suitable test compounds for proof of concept in the subsequent experimental part of the project:
DEET (CAS 134-62-3)
Icaridine (CAS 119515-38-7)
EBAAP (CAS 52304-36-6)
Another promising candidate for infochemical effects is isophorone (CAS 78-59-1), a natural attractant and an anthropogenic high production volume solvent.
Conclusions
Four chemicals were selected with the expectation that they may be suitable test substances for experimental proof of concept of infochemical effects in the subsequent part of the project. The experimental results may then help to answer the question of whether PT 19 biocides and other odourants entering aquatic ecosystems give rise for concern about potential infochemical effects.
Quelle: http://www.enveurope.comVeröffentlichung Determination of tributyltin in whole water matrices under the European Water Framework Directive(2016) Richter, Janine; Fettig, Ina; Philipp, Rosemarie; Jakubowskia, Norbert; Panne, Ulrich; Fisicaro, Paola; Alasonati, EnricaMonitoring of water quality is important to control water pollution. Contamination of the aquatic system has a large effect on human health and the environment. Under the European Water Framework Directive (WFD) 2000/60/EC and the related directive on environmental quality standards (EQS) in the field of water policy 2008/105/EC, the need for sensitive reference methods was highlighted. Since tributyltin (TBT) is one of the WFD listed priority substances a method was developed which is capable to qualify and quantify the pollutant at the required low WFD EQS of 0.2 ng L-1 in whole water bodies, i.e. in non-filtered water samples with dissolved organic carbon and suspended particulate matter. Therefore special attention was paid on the interaction of TBT with the suspended particulate matter and humic substances to obtain a complete representation of the pollution in surface waters. Different water samples were investigated varying the content of organic dissolved and suspended matter. Quantification was performed using species-specific isotope dilution (SSID) and gas chromatography with inductively coupled plasma mass spectrometry (GC-ICP-MS). Different sample treatment strategies were evaluated and compared. The process of internal standard addition was investigated and optimized, hence the equilibrium between internal standards and matrix is of primary importance to perform accurate SSID. Samples spiked at EQS level were analyzed with a recovery between 95 and 105 %. Additionally real surface water samples were investigated and the TBT concentration for the whole water body was determined and compared with conventional routine analysis method.Quelle: http://www.sciencedirect.comVeröffentlichung Evaluation of the impact of construction products on the environment by leaching of possibly hazardous substances(2018) Bandow, Nicole; Gartiser, Stefan; Ilvonen, OutiConstruction products are in contact with water (e.g., rain, seepage water) during their service lifetime and may release potentially harmful compounds by leaching processes. Monitoring studies showed that compounds attributed to construction products are found in storm water and the receiving bodies of water and that the release of biocides in urban areas can be comparable to the input of pesticides from agricultural uses. Therefore, a prospective risk assessment of such products is necessary. Laboratory leaching tests have been developed by the Technical Committee CEN/TC 351 and are ready to use. One major task in the future will be the evaluation of the leaching test results, as concentrations found in laboratory experiments are not directly comparable to the field situations. Another task will be the selection of compounds to be considered for construction products, which are often a complex mixture and contain additives, pigments, stabilization agents, etc. The formulations of the products may serve as a starting point, but total content is a poor predictor for leachability, and analysis of the eluates is necessary. In some cases, non-targeted approaches might be required to identify compounds in the eluates. In the identification process, plausibility checks referring to available information should be included. Ecotoxicological tests are a complementary method to test eluates, and the combined effects of all compounds-including degradation products-are included. A bio test battery has been applied in a round robin test and was published in a guidance document. Published studies on the ecotoxicity of construction products show the tests' suitability to distinguish between products with small and larger effects on the environment. Quelle: https://link.springer.comVeröffentlichung Transport and retention of differently coated CeO2 nanoparticles in saturated sediment columns under laboratory and near-natural conditions(2019) Degenkolb, Laura; Dippon-Deissler, Urs; Klitzke, Sondra; Pabst, SilkeWhere surface-functionalized engineered nanoparticles (NP) occur in drinking water catchments, understanding their transport within and between environmental compartments such as surface water and groundwater is crucial for risk assessment of drinking water resources. The transport of NP is mainly controlled by (i) their surface properties, (ii) water chemistry, and (iii) surface properties of the stationary phase. Therefore, functionalization of NP surfaces by organic coatings may change their fate in the environment. In laboratory columns, we compared the mobility of CeO2 NP coated by the synthetic polymer polyacrylic acid (PAA) with CeO2 NP coated by natural organic matter (NOM) and humic acid (HA), respectively. The effect of ionic strength on transport in sand columns was investigated using deionized (DI) water and natural surface water with 2.2 mM Ca2+ (soft) and 4.5 mM Ca2+ (hard), respectively. Furthermore, the relevance of these findings was validated in a near-natural bank filtration experiment using HA-CeO2 NP. PAA-CeO2 NP were mobile under all tested water conditions, showing a breakthrough of 60% irrespective of the Ca2+ concentration. In contrast, NOM-CeO2 NP showed a lower mobility with a breakthrough of 27% in DI and < 10% in soft surface water. In hard surface water, NOM-CeO2 NP were completely retained in the first 2 cm of the column. The transport of HA-CeO2 NP in laboratory columns in soft surface water was lower compared to NOM-CeO2 NP with a strong accumulation of CeO2 NP in the first few centimeters of the column. Natural coatings were generally less stabilizing and more susceptible to increasing Ca2+ concentrations than the synthetic coating. The outdoor column experiment confirmed the low mobility of HA-CeO2 NP under more complex environmental conditions. From our experiments, we conclude that the synthetic polymer is more efficient in facilitating NP transport than natural coatings and hence, CeO2 NP mobility may vary significantly depending on the surface coating. © The Author(s) 2019Veröffentlichung Detection and characterization of hepatitis E virus genotype 3 in wastewater and urban surface waters in Germany(2020) Beyer, Sophia; Gnirrs, Regina; Selinka, Hans-Christoph; Szewzyk, RegineIn highly populated areas, environmental surveillance of wastewater and surface waters is a key factor to control the circulation of viruses and risks for public health. Hepatitis E virus (HEV) genotype 3 is considered as an emerging pathogen in industrialized countries. Therefore, this study was carried out to determine the prevalence of HEV in environmental waters in urban and suburban regions in Germany. HEV was monitored in water samples using quantitative RT-PCR (RT-qPCR) and nested RT-PCR without or with virus concentration via polyethylene glycol precipitation or ultracentrifugation. By RT-qPCR, 84-100% of influent samples of wastewater treatment plants were positive for HEV RNA. Genotypes HEV-3c and 3f were identified in wastewater, with HEV-3c being the most prevalent genotype. These data correlate with subtypes identified earlier in patients from the same area. Comparison of wastewater influent and effluent samples revealed a reduction of HEV RNA of about 1 log10 during passage through wastewater treatment plants. In addition, combined sewer overflows (CSOs) after heavy rainfalls were shown to release HEV RNA into surface waters. About 75% of urban river samples taken during these CSO events were positive for HEV RNA by RT-qPCR. In contrast, under normal weather conditions, only around 30% of river samples and 15% of samples from a bathing water located at an urban river were positive for HEV. Median concentrations of HEV RNA of all tested samples at this bathing water were below the limit of detection. Source: https://link.springer.comVeröffentlichung 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 Exploring surface water as a transmission medium of avian influenza viruses - systematic infection studies in mallards(2022) Ahrens, Ann Kathrin; Mettenleiter, Thomas C.; Selinka, Hans-ChristophMallards (Anas platyrhynchos) are an abundant anseriform migratory wild bird species worldwide and an important reservoir for the maintenance of low pathogenicity (LP) avian influenza viruses (AIV). They have also been implicated in the spread of high pathogenicity (HP) AIV after spill-over events from HPAIV-infected poultry. The spread of HPAIV within wild water bird populations may lead to viral contamination of natural habitats. The role of small shallow water bodies as a transmission medium of AIV among mallards is investigated here in three experimental settings. (i) Delayed onset but rapid progression of infection seeded by two mallards inoculated with either LP or HP AIV to each eight sentinel mallards was observed in groups with access to a small 100 L water pool. In contrast, groups with a bell drinker as the sole source of drinking water showed a rapid onset but lengthened course of infection. (ii) HPAIV infection also set off when virus was dispersed in the water pool; titres as low as 102 TCID50 L-1 (translating to 0.1 TCID50 mL-1) proved to be sufficient. (iii) Substantial loads of viral RNA (and infectivity) were also found on the surface of the birds' breast plumage. "Unloading" of virus infectivity from contaminated plumage into water bodies may be an efficient mechanism of virus spread by infected mallards. However, transposure of HPAIV via the plumage of an uninfected mallard failed. We conclude, surface water in small shallow water bodies may play an important role as a mediator of AIV infection of aquatic wild birds. © 2022 The Author(s)Veröffentlichung The fate of nitrification and urease inhibitors in simulated bank filtration(2023) Förster, Christina; Scheurer, Marco; Klitzke, Sondra; Ruhl, Aki Sebastian; Zeeshan, MuhammadThe application of nitrification and urease inhibitors (NUI) in conjunction with nitrogen (N) fertilizers improves the efficiency of N fertilizers. However, NUI are frequently found in surface waters through leaching or surface runoff. Bank filtration (BF) is considered as a low-cost water treatment system providing high quality water by efficiently removing large amounts of organic micropollutants from surface water. The fate of NUI in managed aquifer recharge systems such as BF is poorly known. The aim of this work was to investigate sorption and degradation of NUI in simulated BF under near-natural conditions. Besides, the effect of NUI on the microbial biomass of slowly growing microorganisms and the role of microbial biomass on NUI removal was investigated. Duplicate sand columns (length 1.7 m) fed with surface water were spiked with a pulse consisting of four nitrification (1,2,4-triazole, dicyanodiamide, 3,4-dimethylpyrazole and 3-methylpyrazole) and two urease inhibitors (n-butyl-thiophosphoric acid triamide and n-(2-nitrophenyl) phosphoric triamide). The average spiking concentration of each NUI was 5 ÎÌg/L. Experimental and modeled breakthrough curves of NUI indicated no retardation for any of the inhibitors. Therefore, biodegradation was identified as the main elimination pathway for all substances and was highest in zones of high microbial biomass. Removal of 1,2,4-triazole was 50% and n-butyl-thiophosphoric acid triamide proved to be highly degradable and was completely removed after a hydraulic retention time (HRT) of 24 h. 50% of the mass recovery for nitrification inhibitors except for 3,4-dimethylpyrazole was observed at the effluent (4 days HRT). In addition, a mild effect of NUI on microbial biomass was noted. This study highlights that the degradation of NUI in BF depends on HRT and microbial biomass. © 2023 ElsevierVeröffentlichung Investigating environmental matrices for use in avian influenza virus surveillance - surface water, sediments, and avian fecal samples(2023) Ahrens, Ann Kathrin; Selinka, Hans-Christoph; Wylezich, ClaudiaSurveillance of avian influenza viruses (AIV) in wild water bird populations is important for early warning to protect poultry from incursions of high-pathogenicity (HP) AIV. Access to individual water birds is difficult and restricted and limits sampling depth. Here, we focused on environmental samples such as surface water, sediments, and environmentally deposited fresh avian feces as matrices for AIV detection. Enrichment of viral particles by ultrafiltration of 10-L surface water samples using Rexeed-25-A devices was validated using a bacteriophage Phi 6 internal control system, and AIV detection was attempted using real-time RT-PCR and virus isolation. While validation runs suggested an average enrichment of about 60-fold, lower values of 10 to 15 were observed for field water samples. In total 25/36 (60%) of water samples and 18/36 (50%) of corresponding sediment samples tested AIV positive. Samples were obtained from shallow water bodies in habitats with large numbers of waterfowl during an HPAIV epizootic. Although AIV RNA was detected in a substantial percentage of samples virus isolation failed. Virus loads in samples often were too low to allow further sub- and pathotyping. Similar results were obtained with environmentally deposited avian feces. Moreover, the spectrum of viruses detected by these active surveillance methods did not fully mirror an ongoing HPAIV epizootic among waterfowl as detected by passive surveillance, which, in terms of sensitivity, remains unsurpassed. © 2023 Ahrens et al.Veröffentlichung Application of High-Resolution Near-Infrared Imaging Spectroscopy to Detect Microplastic Particles in Different Environmental Compartments(2023) Munz, Matthias; Bannick, Claus Gerhard; Kreiß, Jasper; Bednarz, Marius; Krüger, LisaMicroplastic particles (MPP) occur in various environmental compartments all over the world. They have been frequently investigated in oceans, freshwaters, and sediments, but studying their distribution in space and time is somewhat limited by the time-consuming nature of the available accurate detection strategies. Here, we present an enhanced application of lab-based near-infrared imaging (NIR) spectroscopy to identify the total number of MPP, classify polymer types, and determine particle sizes while maintaining short measuring times. By adding a microscopic lens to the hyperspectral camera and a cross slide table to the setup, the overall detectable particle size has been decreased to 100 Ìm in diameter. To verify and highlight the capabilities of this enhanced, semi-automated detection strategy, it was applied to key areas of microplastic research, such as a lowland river, the adjacent groundwater wells, and marine beach sediments. Results showed mean microplastic concentrations of 0.65 MPP/L in the Havel River close to Berlin and 0.004 MPP/L in the adjacent groundwater. The majority of MPP detected in the river were PP and PE. In 8 out of 15 groundwater samples, no MPP was found. Considering only the samples with quantifiable MPP, then on average 0.01 MPP/L was present in the groundwater (98.5% removal during bank filtration). The most abundant polymers in groundwater were PE, followed by PVC, PET, and PS. Mean MPP concentrations at two beaches on the German Baltic Sea coast were 5.5~MPP/kg at the natural reserve Heiligensee and Hüttelmoor and 47.5 MPP/kg at the highly frequented Warnemünde beach. Quelle: link.springer.com