North Rhine Westphalian State Agency for Nature

Essen, Germany

North Rhine Westphalian State Agency for Nature

Essen, Germany
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Euler T.,North Rhine Westphalian State Agency for Nature | Herget J.,University of Bonn | Schlomer O.,University of Bonn | Benito G.,CSIC - National Museum of Natural Sciences
Catena | Year: 2017

A series of 51 experiments was conducted in a laboratory flume to investigate hydromorphological processes at submerged solitary boulder-like obstacles. As part of a programme to validate the experimental results, five sites with obstacle marks at large boulders were surveyed in two gravel-bed ephemeral streams located in eastern Spain. Three hydromorphological system states (I–III) were observed, each exhibiting characteristic dynamic interactions between hydraulic and sedimentary processes: (I) wake-vortex domination and absent scouring; (II) wake-vortex domination and downstream scouring; (III) horseshoe-vortex domination, frontal scouring and ridge-like sediment accumulation at the lee-side. The latter system state (III) comprises ‘typical’ fluvial obstacle marks. In mobile alluvial beds, obstacles may tilt upstream into the scour hole when frontal scour depths exceed 0.6 times obstacle length, favouring the rapid achievement of steady state conditions (state III). Field and experimentally modelled obstacle marks are related to each other when frontal scour depth, -width and -length as well as ridge width are used as morphometric variables. An analytical model was adapted and successfully applied for determination of these variables at the steady state condition. The model was also used to assess the critical threshold for the formation of obstacle marks. It integrates mean flow velocity, water depth, obstacle height and width, obstacle shape, median grain size relative to obstacle width and grain size distribution. Dynamic interactions between hydraulic processes and sediment exchange around obstacles, together with well-defined boundaries between evolutionary states (critical thresholds), suggest a self-organised, scale-invariant mechanism driving the generation of obstacle marks. © 2017 Elsevier B.V.


Klees M.,North Rhine Westphalian State Agency for Nature | Hombrecher K.,North Rhine Westphalian State Agency for Nature | Gladtke D.,North Rhine Westphalian State Agency for Nature
Science of the Total Environment | Year: 2017

During this study the occurrence of polychlorinated biphenyls (PCBs) in the surrounding of an e-waste recycling facility in North-Rhine Westphalia was analysed. PCB levels were analysed in curly kale, spruce needles, street dusts and dusts. Conspicuously high PCB concentrations in curly kale and spruce needles were found directly northwards of the industrial premises. Furthermore a concentration gradient originating from the industrial premises to the residential areas in direction southwest to northeast was evident. Homologue patterns of highly PCB contaminated dusts and street dusts were comparable to the homologue patterns of PCB in curly kale and spruce needles. This corroborates the suspicion that the activities at the e-waste recycling facility were responsible for the elevated PCB levels in curly kale and spruce needles. The utilization of multiple linear regression of wind direction data and analysed PCB concentrations in spruce needles proved that the e-waste recycling facility caused the PCB emissions to the surrounding. Additionally, this evaluation enabled the calculation of source specific accumulation constants for certain parts of the facility. Consequently the different facility parts contribute with different impacts to the PCB levels in bioindicators. © 2017 Elsevier B.V.


Klees M.,North Rhine Westphalian State Agency for Nature | Klees M.,University of Duisburg - Essen | Hiester E.,North Rhine Westphalian State Agency for Nature | Bruckmann P.,North Rhine Westphalian State Agency for Nature | And 2 more authors.
Science of the Total Environment | Year: 2015

In this study the occurrence of polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/PCDFs) in street dust samples was investigated using pressurized liquid extraction and gas chromatography coupled to mass spectrometry. Street dust samples were taken from rural, urban, industrial and industrially influenced urban areas. PCB6 concentrations ranged from 5090±2200μg/kg (average±standard error of mean) in dusts from industrial premises to 29±8.7μg/kg in rural areas. Concentration ranges were for dioxin-like PCB toxicity equivalents (dl-PCB TEQ) from 362±164ng/kg (industrial premises) to 6.5±1.8ng/kg (rural areas), and for PCDD/PCDF TEQ from 503±448ng/kg to 2.4±0.13ng/kg, respectively. Area concentrations of PCB6 (0.040μg/m2-22μg/m2), dl-PCB TEQ (0.0038ng/m2-2.6ng/m2) and PCDD/PCDF TEQs (14pg/m2-1980pg/m2) were estimated. Furthermore, particle size related concentrations of PCBs and PCDD/PCDFs in street dusts were analysed showing throughout almost all samples a distinctive trend of increasing concentrations with decreasing particle sizes. Characterization of homologue patterns of PCBs and PCDDs/PCDFs in street dusts was performed showing a dependence of homologue patterns on different area types, especially for PCBs. It could be demonstrated that the analysis of concentrations in combination with specific homologue patterns of PCBs and PCDDs/PCDFs in street dust samples enables allocation of potential emission sources. © 2014 Elsevier B.V.


Klees M.,North Rhine Westphalian State Agency for Nature | Klees M.,University of Duisburg - Essen | Hiester E.,North Rhine Westphalian State Agency for Nature | Schmidt T.C.,University of Duisburg - Essen
Science of the Total Environment | Year: 2015

During this study wipe sampling was applied to various impervious surfaces for the determination of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFs) area concentrations. To that end, a wipe sampling method based on solvent wetted cotton wipes was evaluated and transfer efficiencies of PCBs and PCDD/PCDFs in particulate films (PFs) and oily liquid films (OFs) during sampling were investigated. For PFs sufficient transfer efficiencies of low concentrated PCB and PCDD/PCDF congeners in 1g/m2 spiking surrogate were achieved after the first wipe using n-hexane as wetting solvent. Transfer efficiencies for OFs were the highest in the first wipe if n-hexane or n-heptane were used rather than toluene. The spiking experiments of OFs showed a log-linear correlation between the number of wiping procedures and transfer efficiency which indicates that transfer efficiencies were constant in subsequent wipes. Furthermore, it was successfully demonstrated that pressurized liquid extraction is a suitable tool for the extraction of wipe samples. Finally, the feasibility of this wipe sampling method was demonstrated on various impervious surfaces of different origin, and concentration levels of PCBs and PCDD/PCDFs in wipe samples are discussed. Hereby, remarkably high ∑CB6 concentrations of up to 1400μg/m2 (taken at a transformer recycling site) were detected. © 2015.


Klees M.,North Rhine Westphalian State Agency for Nature | Klees M.,University of Duisburg - Essen | Hiester E.,North Rhine Westphalian State Agency for Nature | Bruckmann P.,North Rhine Westphalian State Agency for Nature | Schmidt T.C.,University of Duisburg - Essen
Journal of Chromatography A | Year: 2013

Owing to massive pollution with polychlorinated biphenyls in the harbour area of Dortmund (Germany), several dust samples were taken from surfaces at industrial sites and analyzed by the North-Rhine Westphalian State Agency for Nature, Environment, and Consumer Protection (LANUV NRW). This report describes and validates a rapid approach to screening for the presence of polychlorinated biphenyls (PCBs) in street dust. Samples were collected by using a natural bristle brush and stainless steel scoops. Mass recovery of fine-particle sea sand (a dust surrogate) on asphalt and concrete surfaces was used as a criterion for the effectiveness of sampling. Better recoveries of sea sand were achieved on concrete than on asphalt surfaces. Furthermore, temperature optimization for a pressurized liquid extraction (PLE) method used to extract PCBs and polychlorinated dibenzodioxins and polychlorinated furans (PCDD/Fs) from street dust samples was developed and compared with Soxhlet extraction for the analysis of PCBs in real street dust samples. Toluene was used as the extraction solvent in both cases. During this study, a combination of toluene and PLE achieved better extraction efficiencies than Soxhlet extraction. Finally, the performance of the PLE method was evaluated by analysing NIST Standard Reference Material 1649a for PCB and PCDD/F concentrations. This demonstrated that the accuracy of the PLE method for the determination of both substance classes was satisfactory. In addition, concentrations of PCBs and PCDD/Fs in street dust samples from industrial sites are reported. © 2013.


PubMed | North Rhine Westphalian State Agency for Nature and University of Duisburg - Essen
Type: | Journal: The Science of the total environment | Year: 2015

During this study wipe sampling was applied to various impervious surfaces for the determination of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFs) area concentrations. To that end, a wipe sampling method based on solvent wetted cotton wipes was evaluated and transfer efficiencies of PCBs and PCDD/PCDFs in particulate films (PFs) and oily liquid films (OFs) during sampling were investigated. For PFs sufficient transfer efficiencies of low concentrated PCB and PCDD/PCDF congeners in 1g/m(2) spiking surrogate were achieved after the first wipe using n-hexane as wetting solvent. Transfer efficiencies for OFs were the highest in the first wipe if n-hexane or n-heptane were used rather than toluene. The spiking experiments of OFs showed a log-linear correlation between the number of wiping procedures and transfer efficiency which indicates that transfer efficiencies were constant in subsequent wipes. Furthermore, it was successfully demonstrated that pressurized liquid extraction is a suitable tool for the extraction of wipe samples. Finally, the feasibility of this wipe sampling method was demonstrated on various impervious surfaces of different origin, and concentration levels of PCBs and PCDD/PCDFs in wipe samples are discussed. Hereby, remarkably high CB6 concentrations of up to 1400g/m(2) (taken at a transformer recycling site) were detected.


Fliedner A.,Fraunhofer Institute for Molecular Biology and Applied Ecology | Rudel H.,Fraunhofer Institute for Molecular Biology and Applied Ecology | Teubner D.,University of Trier | Buchmeier G.,Bavarian Environmental Agency LfU | And 4 more authors.
Environmental Science and Pollution Research | Year: 2016

We compare the results of different monitoring programs regarding spatial and temporal trends of priority hazardous substances of the European Water Framework Directive (WFD). Fish monitoring data for hexachlorobenzene (HCB), mercury (Hg), and perfluorooctane sulfonic acid (PFOS) sampled in German freshwaters between the mid-1990s and 2014 were evaluated according to the recommendations of the 2014 adopted WFD guidance document on biota monitoring, i.e., normalization to 5 % lipid content (HCB) or 26 % dry mass (Hg, PFOS) and adjustment to trophic level (TL) 4. Data of the German Environmental Specimen Bank (ESB) (annual pooled samples of bream) were compared to monitoring data of the German federal states (FS), which refer to individual fish of different species. Significant decreasing trends (p < 0.01) were detected for Hg in bream (Abramis brama) sampled by both, the ESB and the FS between 1993 and 2013 but not for FS samples comprising different fish species. Data for HCB and PFOS were more heterogeneous due to a smaller database and gave no consistent results. Obviously, normalization could not compensate differences in sampling strategies. The results suggest that the data treatment procedure proposed in the guidance document has shortcomings and emphasize the importance of highly standardized sampling programs in trend monitoring or whenever results between sites have to be compared. © 2016 The Author(s)


Guhl B.,North Rhine Westphalian State Agency for Nature | Sturenberg F.-J.,North Rhine Westphalian State Agency for Nature | Santora G.,North Rhine Westphalian State Agency for Nature
Environmental Sciences Europe | Year: 2014

Background: Populations of the European eel (Anguilla anguilla) are declining rapidly and are now considered below safe biological limits. High pollution levels are one of the possible reasons for this decline. Contaminant levels are also of concern with regard to human consumption. This study examined the contamination levels of eels from the North Rhine-Westphalian catchment area of the Rhine and from adjacent rivers. A total of 119 eels from 13 sampling sites were analysed for polychlorinated dibenzo-p-dioxins and furans (PCDD/PCDFs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), mercury, perfluorooctane sulfonate (PFOS) and hexachlorobenzene (HCB).Results: North Rhine-Westphalian eels had very high levels of contaminants comparable to eels from other European water bodies which are strongly influenced by anthropogenic activities. Mean values for PCDD/PCDFs ranged between 0.5 and 5.4 pg WHO2005 toxicity equivalents (TEQ)/g, for PCDD/PCDF + dl-PCBs between 6.3 and 44.7 pg WHO2005 TEQ/g, for indicator PCBs between 165 and 1,630 ng/g wet weight (ww), for 6 PBDEs between 9.2 and 242 μg/kg ww, for mercury between 0.069 and 0.314 mg/kg ww, for PFOS between 8.3 and 49 μg/kg ww and for HCB between 3.4 and 50 μg/kg ww. For certain sampling sites, high contamination contents of the eels could be attributed to local sources. Congener patterns for PCBs and PBDEs were described, and biota to suspended matter ratios were calculated.Conclusions: Pollution levels in eels from North Rhine-Westphalia are declining with regard to some contaminants but are still very high. Due to the high contaminant contents, eels from the rivers investigated are not suitable for human consumption. Furthermore, the concentrations of endocrine disrupting contaminants such as PCBs, PCDD/PCDFs and PBDEs in the eels are in a range which might have deleterious effects on the eel populations. © 2014, Guhl et al.; licensee Springer.


Bruckmann P.,North Rhine Westphalian State Agency for Nature | Hiester E.,North Rhine Westphalian State Agency for Nature | Klees M.,North Rhine Westphalian State Agency for Nature | Zetzsch C.,University of Bayreuth
Chemosphere | Year: 2013

Time series of polychlorinated dioxins and furans (PCDD/F) and polychlorinated biphenyls (PCB) in ambient air of a large conurbation in North-Western Germany are presented and analyzed. The trend of PCDD/F concentrations, starting from as early as 1988, shows a pronounced decrease by at least one order of magnitude, demonstrating that the emission reductions were effective. The PCDD/F depositions also have decreased by a factor of 5 since 1992. However, both trends have leveled out since 2005. Time series of PCB concentrations and depositions starting in 1994 show only slight decreases for the concentrations and almost no decrease for the depositions. From the decay rates following first order kinetics, half-lives in the order of 5-15. years for the PCDD/F and 15-31. years for the sum of the six indicator PCB could be calculated, which are much longer than the half-lives estimated from their reactivity towards the OH radical. Apparently, small fresh emissions (PCDD/F), considerable secondary emissions and evaporation from contaminated soils slow down their decay in the atmosphere of big conurbations. Analyzing the decay rates of individual PCB congeners shows that the lower chlorinated and more volatile ones are removed faster than the higher chlorinated congeners, probably via gas phase reactions with the OH radical. It can be concluded from the present study that the input of PCDD/F and PCB into the food chain via the air path will continue for another one or two decades in big conurbations. © 2013 Elsevier Ltd.


PubMed | North Rhine Westphalian State Agency for Nature
Type: | Journal: Journal of chromatography. A | Year: 2016

During this study a high throughout selective pressurized liquid extraction (SPLE) method was developed and validated for the simultaneous extraction of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/PCDFs) and polychlorinated biphenyls (PCBs) from soil. To that end, extraction rates of PCBs from soil utilizing different extraction solvents and different extraction temperatures were investigated whereas extraction rates were comparable for toluene, n-hexane and dichloromethane (extraction conditions for all utilized solvents: 33mL PLE extraction cell, extraction temperature: 110C, static extraction time: 5min, flush volume: 60%, purge 90s). Ratios of native PCBs and PCDD/PCDFs congener concentrations after Soxhlet and selective pressurized liquid extraction (SPLE) showed that SPLE is an alternative sample preparation step for the simultaneous determination of PCDD/PCDFs and PCBs in soil. Additional clean-up steps for the separation of PCBs and PCDD/PCDFs utilizing alumina were performed in order to avoid interferences between the component classes.

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