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Found 36 results.

Handling of radium and uranium contaminated waste piles and other wastes from phosphate ore processing

Das Projekt "Handling of radium and uranium contaminated waste piles and other wastes from phosphate ore processing" wird vom Umweltbundesamt gefördert und von Öko-Institut. Institut für angewandte Ökologie e.V. durchgeführt.

Bees in Europe and Sustainable Honey Production (BEE SHOP)

Das Projekt "Bees in Europe and Sustainable Honey Production (BEE SHOP)" wird vom Umweltbundesamt gefördert und von Universität Halle-Wittenberg, Fachbereich Biologie, Institut für Zoologie, Arbeitsgruppe Molekulare Ökologie durchgeführt. Honey is among the oldest food products of mankind and beekeeping is deeply rooted in every European culture. Numerous European and national regulations control honey quality, which reflects both the high nutritional and societal value of the product. Yet in an environment with increasing chemical pollution and the wide use of agrochemicals, honey runs high risks of becoming chemically polluted. In addition a broad spectrum of chemicals is used to treat honeybee diseases, further contaminating honey with sometimes highly toxic compounds. The BEE SHOP is a network of ten leading European honeybee research groups in honey quality, pathology, genetics and behaviour as well as selected beekeeping industries, which all share a common interest in promoting Europe's high honey quality standards. The prime goal is to reduce potential sources of honey contamination due to both foraging contaminated nectar and chemotherapy of honeybee diseases. The BEE SHOP will therefore deal with the development of biological resistance to pests and pathogens to avoid chemotherapy. Various European honeybee races and populations will be screened for their disease resistance potential to the main pressing pathogens. Differences in foraging patterns among European honeybees and their underlying mechanisms will be studied to identify behavioural traits reducing contamination. Differences in disease susceptibility will be genetically analysed by QTL mapping. Major loci in the genome will be identified with the aid of the published honeybee genome. SNPs will be developed to allow for selection of specific target genes in both drones and queens before insemination. This will greatly accelerate the selection progress in honeybee breeding allowing for the swift establishment of resistant but efficient stock. New tools for testing honey quality and authenticity will be developed to allow inspections of honey according to the current EC directives on honey quality and organic beekeeping.

Immobilisation of arsenic in paddy soil by iron(II)-oxidizing bacteria

Das Projekt "Immobilisation of arsenic in paddy soil by iron(II)-oxidizing bacteria" wird vom Umweltbundesamt gefördert und von Universität Tübingen, Institut für Geowissenschaften, Zentrum für Angewandte Geowissenschaften durchgeführt. Arsenic-contaminated ground- and drinking water is a global environmental problem with about 1-2Prozent of the world's population being affected. The upper drinking water limit for arsenic (10 Micro g/l) recommended by the WHO is often exceeded, even in industrial nations in Europe and the USA. Chronic intake of arsenic causes severe health problems like skin diseases (e.g. blackfoot disease) and cancer. In addition to drinking water, seafood and rice are the main reservoirs for arsenic uptake. Arsenic is oftentimes of geogenic origin and in the environment it is mainly bound to iron(III) minerals. Iron(III)-reducing bacteria are able to dissolve these iron minerals and therefore release the arsenic to the environment. In turn, iron(II)-oxidizing bacteria have the potential to co-precipitate or sorb arsenic during iron(II)- oxidation at neutral pH followed by iron(III) mineral precipitation. This process may reduce arsenic concentrations in the environment drastically, lowering the potential risk for humans dramatically.The main goal of this study therefore is to quantify, identify and isolate anaerobic and aerobic Fe(II)-oxidizing microorganisms in arsenic-containing paddy soil. The co-precipitation and thus removal of arsenic by iron mineral producing bacteria will be determined in batch and microcosm experiments. Finally the influence of rhizosphere redox status on microbial Fe oxidation and arsenic uptake into rice plants will be evaluated in microcosm experiments. The long-term goal of this research is to better understand arsenic-co-precipitation and thus arsenic-immobilization by iron(II)-oxidizing bacteria in rice paddy soil. Potentially these results can lead to an improvement of living conditions in affected countries, e.g. in China or Bangladesh.

SAFIRA - Abstracts of the Workshop of November 17-18, 1999 at Bitterfeld / Germany

Das Projekt "SAFIRA - Abstracts of the Workshop of November 17-18, 1999 at Bitterfeld / Germany" wird vom Umweltbundesamt gefördert und von Umweltforschungszentrum Leipzig-Halle, Projektbereich Industrie- und Bergbaufolgelandschaften durchgeführt. The SAFIRA project (Sanierungsforschung in regional kontaminierten Aquiferen) focuses an the development of reactive walls for the treatment of regional contaminated aquifers. The project is managed by UFZ (Umweltforschungszentrum Leipzig-Halle) and the University of Tübingen. Within the SAFIRA project, different research groups are investigating a number of different technologies at an underground test site in Bitterfeld. Among them is a consortium from the Netherlands, lead by TNO (Netherlands Organisation for Applied Scientific Research), with Tebodin, HBG/HWZ and Shell as partners. The Dutch research project is supported by NOBIS (Netherlands Research Programme for Biological in situ Remediation). Fall 1999, the SAFIRA programme at Bitterfeld had come at an interesting point. The test site had been officially opened, most results of the on-site mobile test unit had been obtained and the in-situ reactors had been started up. On November 17-18, 1999, UFZ and TNO jointly organised a workshop at the test site in Bitterfeld. The Workshop was attended by about 50 representatives from the different research groups involved in SAFIRA, NOBIS representatives and members of the Knowledge Exchange Group related to the Dutch research project. The workshop focused on: - the methods applied; - the results obtained so far; - practical, large scale solutions for the regional groundwater problem. This report presents the workshop programme, the abstracts of the presentations and a selection of the slides that were used within the brainstorm session. We do hope that the workshop and this report will be followed-up by a further and fruitful knowledge exchange between all parties involved and that this may contribute to finding innovative, optimal solutions for the regional groundwater problems in Bitterfeld and other areas.

Effectiveness of low emission zones: Large scale analysis of changes in environmental NO2, NO and NOx concentrations in 17 German cities

Das Projekt "Effectiveness of low emission zones: Large scale analysis of changes in environmental NO2, NO and NOx concentrations in 17 German cities" wird vom Umweltbundesamt gefördert und von Evonik Industries AG durchgeführt. Background: Low Emission Zones (LEZs) are areas or roads where the most polluting vehicles are restricted from entering. The effectiveness of LEZs to lower ambient exposures is under debate. This study focused on LEZs that restricted cars of Euro 1 standard without appropriate retrofitting systems from entering and estimated LEZ effects on NO2, NO, and NOx (=NO2+NO) concentrations. Methods: Continuous half-hour and diffuse sampler 4-week average NO2, NO, and NOx concentrations measured inside and outside LEZs in 17 German cities of 6 federal states (2005-2009) were analysed as matched quadruplets (two pairs of simultaneously measured index values inside LEZ and reference values outside LEZ, one pair measured before and one after introducing LEZs with time differences that equal multiples of 364 days) by multiple linear and log-linear fixed-effects regression modelling (covariables: e.g., wind velocity, amount of precipitation, height of inversion base, school holidays, truck-free periods). Additionally, the continuous half-hour data was collapsed into 4-week averages and pooled with the diffuse sampler data to perform joint analysis. Results: More than 3,000,000 quadruplets of continuous measurements (half-hour averages) were identified at 38 index and 45 reference stations. Pooling with diffuse sampler data from 15 index and 10 reference stations lead to more than 4,000 quadruplets for joint analyses of 4-week averages. Mean LEZ effects on NO2, NO, and NOx concentrations (reductions) were estimated to be at most - 2 microgram/m3 (or - 4 percent). The 4-week averages of NO2 concentrations at index stations after LEZ introduction were 55 microgram/m3 (median and mean values) or 82 microgram/m3 (95th percentile). Conclusion: This is the first study investigating comprehensively the effectiveness of LEZs to reduce NO2, NO, and NOx concentrations controlling for most relevant potential confounders. Our analyses indicate that there is a significant, but rather small reduction of NO2, NO, and NOx concentrations associated with LEZs. Key words: air quality, low emission zone, NO2, NO and NOx, air pollution

Microbial processes and iron-mineral formation in household sand filters used to remove arsenic from drinking water in Vietnam

Das Projekt "Microbial processes and iron-mineral formation in household sand filters used to remove arsenic from drinking water in Vietnam" wird vom Umweltbundesamt gefördert und von Universität Tübingen, Zentrum für Angewandte Geowissenschaften (ZAG), Arbeitsgruppe Geomikrobiologie durchgeführt. Arsenic-contaminated ground- and drinking water is a global environmental problem with about 1-2Prozent of the worlds population being affected. The upper drinking water limit for arsenic (10 ìg/L) is often exceeded, especially in Asian countries, such as Vietnam. Household sand filters are already used as one very simple and cost-efficient treatment to remove arsenic from water. Oxidation of dissolved iron (Fe(II)) present in the groundwater leads to the formation of sparsely soluble iron(hydr)oxide particles (Fe(III)OOH) in the sand filter, which bind negatively charged arsenic species and reduce arsenic concentrations in the water. Arsenite (As(III); H3AsO3) binds generally less strong to metal oxides than arsenate (As(V); H2AsO4 -/HAsO4 2-), therefore As(V) is removed much more effectively than As(III). This is why As(III) oxidation to As(V) is of special interest for arsenic removal from drinking water. Whether and how the activity of iron- and arsenite-oxidizing bacteria contributes to effective arsenic removal in household sand filters is currently not known. One of the goals of this study therefore is to isolate, identify, and quantify Fe(II)- and As(III)-oxidizing microorganisms from filters and to study their iron and arsenic redox activities. Cultivation-based work will be complemented by molecular, cultivation-independent techniques to characterize and quantify the microbial communities in samples from different filter locations taken at various time points during filter operation (both at field sites and in artificial laboratory filter systems). The isolated iron- and arsenite-oxidizing bacteria will be studied with respect to their abilities to precipitate iron minerals (in the presence or absence of arsenic) and oxidize arsenite. Biogenic and abiogenic iron minerals formed by the isolated strains in the lab, on the sand filter material in Vietnam and in artificial laboratory filter systems will be identified and characterized, also with respect to arsenic sorption. And we will determine how biotic and abiotic processes that contribute to arsenic mobilization from arsenic-loaded iron mineral phases affect filter performance over time. The long-term goal of this research is to better understand the microbial redox transformation processes that drive arsenic/iron mineral interactions in natural and engineered systems, such as household sand filters and to give recommendations for improved filter use and filter material disposal.

Einfluss der Klärschlamm Prozessierung auf das Schicksal von Nonylphenol in klärschlammbehandelten Böden

Das Projekt "Einfluss der Klärschlamm Prozessierung auf das Schicksal von Nonylphenol in klärschlammbehandelten Böden" wird vom Umweltbundesamt gefördert und von RWTH Aachen University, Institut für Umweltforschung, Biologie V, Lehrstuhl für Umweltbiologie und -chemodynamik durchgeführt. Lipophile endokrin wirksame Chemikalien, z.B. synthetische Kontrazeptiva, reichern sich im bei der Abwasserbehandlung entstehenden Klärschlamm an. Wird dieser Klärschlamm als Dünger landwirtschaftlich genutzter Flächen verwendet, besteht die Gefahr, dass die Fremdstoffe aus dem Boden durch Run-off ausgetragen oder von Pflanzen aufgenommen wird. Aufgrund der verschiedenen Aufarbeitungsschritte des Klärschlamms - Stabilisierung, Konditionierung, Entwässerung, Entpathogenisierung - entstehen Klärschlämme, die sich in ihren physikochemischen Eigenschaften (Mineralgehalt, pH, Fein- und Grobstruktur) und in ihrem Gehalt an Kontaminanten unterscheiden können. Bei der Verwendung dieser Schlämme als Dünger können sich die darin enthaltenen Kontaminanten bezüglich ihres Abbau- und Transpoirtverhaltens sowie der Bioverfügbarkeit unterschiedlich verhalten. In diesem Projekt wird das Umweltverhalten ausgewählter Umweltchemikalien in Klärschlämmen in Abhängigkeit von deren Prozessierung und Aufarbeitung untersucht.

FOR566: Tierarzneimittel in Böden: Grundlagenforschung für die Risikoanalyse, Teilprojekt 'Modellierung der Interaktionen von Dynamik und Wirkung'

Das Projekt "FOR566: Tierarzneimittel in Böden: Grundlagenforschung für die Risikoanalyse, Teilprojekt 'Modellierung der Interaktionen von Dynamik und Wirkung'" wird vom Umweltbundesamt gefördert und von Universität Osnabrück, Institut für Umweltsystemforschung durchgeführt. The simulation models developed in the 1st phase integrate the chemical fate of the veterinary medicines sulfadiazine (SDZ) and difloxacin (DIF) in bulk soil and their subsequent effects on soil microorganisms and on soil functions after single-dose application with manure. In the 2nd project phase, this approach is extended to the rhizosphere, which represents the hotspot of microbial growth in soil and a continuous source of organic compounds released from active roots. The processes of fast and slow sorption, transformation and formation of bound residues of the antibiotics and their main metabolites are adapted to the rhizosphere. The developed effect models for soil functions, structural diversity, and resistance dynamics are extended by relevant plant-soil interactions in close collaboration with the experimental subprojects. The integrated fate-effect model is coupled with a transport model taking heterogeneities of the rhizosphere and plant uptake into account. Processes are parameterized for the two antibiotics SDZ and DIF in rhizosphere and bulk soil with data from the central mesocosm experiment and several planned satellite experiments. The resulting integrated fate-effect models will be evaluated with data from the field experiments. The model is further used to develop indicators such as structural resilience and functional redundancy for antibiotic induced effects, evaluate their applicability for risk assessment and to generate new hypotheses to corroborate the conclusions.

Depletion of algal toxin-contaminated water using selective biofilters based on plant-produced antibodies (plantibodies)

Das Projekt "Depletion of algal toxin-contaminated water using selective biofilters based on plant-produced antibodies (plantibodies)" wird vom Umweltbundesamt gefördert und von Technische Universität München, Institut für Wasserchemie und Chemische Balneologie, Lehrstuhl für Analytische Chemie und Wasserchemie durchgeführt. Although the use of genetically modified plants for bioremediation, or the in situ cleaning of contaminated sites, has been known for quite some time, little attention has so far been paid to the production of antibodies in plants and their ex vivo application in selective depletion. Therefore, highly affine and specific antibodies against algal toxins using microcystin as an example will be produced in plants at low cost within this research project. The basis is a monoclonal antibody (Mab 10E7, species: mouse) generated in a former research project. The sequence of the variable domains will be determined, optimized for plants and sub cloned into suitable plant transformation vectors, which already contain constant antibody sequences. In addition, a scFv fragment containing different tag sequences and fusion proteins will be constructed. Leaf-based (tobacco) as well as seed-based (barley) systems will be used.Affinity-purified plant-produced antibodies (plantibodies) will be characterized in detail for their binding properties using microtitre plate-ELISA and surface plasmon resonance (SPR). The monoclonal mouse antibody will be used as reference. To assure cost-efficiency for future applications, roughly purified fractions (sequential pH and temperature treatment followed by filtration) will be tested for the upscaling. Following immobilization of the plantibody fractions on suitable substrates, for instance membranes, porous polymer monoliths or in porous glasses, their application for depletion will be defined using model water samples spiked fortified with microcystins.

Steady-State Dilution and Mixing-Controlled Reactions in Three-Dimensional Heterogeneous Porous

Das Projekt "Steady-State Dilution and Mixing-Controlled Reactions in Three-Dimensional Heterogeneous Porous" wird vom Umweltbundesamt gefördert und von Eberhard Karls Universität Tübingen, Zentrum für Angewandte Geowissenschaften (ZAG), Arbeitsgruppe Hydrogeology durchgeführt. Understanding transport of contaminants is fundamental for the management of groundwater re-sources and the implementation of remedial strategies. In particular, mixing processes in saturated porous media play a pivotal role in determining the fate and transport of chemicals released in the subsurface. In fact, many abiotic and biological reactions in contaminated aquifers are limited by the availability of reaction partners. Under steady-state flow and transport conditions, dissolved reactants come into contact only through transverse mixing. In homogeneous porous media, transverse mixing is determined by diffusion and pore-scale dispersion, while in heterogeneous formations these local mixing processes are enhanced. Recent studies investigated the enhancement of transverse mixing due to the presence of heterogeneities in two-dimensional systems. Here, mixing enhancement can solely be attributed to flow focusing within high-permeability inclusions. In the proposed work, we will investigate mixing processes in three dimensions using high-resolution laboratory bench-scale experiments and advanced modeling techniques. The objective of the proposed research is to quantitatively assess how 3-D heterogeneity and anisotropy of hydraulic conductivity affect mixing processes via (i) flow focusing and de-focusing, (ii) increase of the plume surface, (iii) twisting and intertwining of streamlines and (iv) compound-specific diffusive/dispersive properties of the solute species undergoing transport. The results of the experimental and modeling investigation will allow us to identify effective large-scale parameters useful for a correct description of conservative and reactive mixing at field scales allowing to explain discrepancies between field observations, bench-scale experiments and current stochastic theory.

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