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Found 36 results.

Effect of diffusive/dispersive processes on stable isotope ratios of organic contaminants in aquifer systems

Groundwater contamination by organic compounds represents a widespread environmental problem. The heterogeneity of geological formations and the complexity of physical and biogeochemical subsurface processes, often hamper a quantitative characterization of contaminated aquifers. Compound specific stable isotope analysis (CSIA) has emerged as a novel approach to investigate contaminant transformation and to relate contaminant sources to downgradient contamination. This method generally assumes that only (bio)chemical transformations are associated with isotope effects. However, recent studies have revealed isotope fractionation of organic contaminants by physical processes, therefore pointing to the need of further research to determine the influence of both transport and reactive processes on the observed overall isotope fractionation. While the effect of gasphase diffusion on isotope ratios has been studied in detail, possible effects of aqueous phase diffusion and dispersion have received little attention so far.The goals of this study are to quantify carbon (13C/12C) and, for chlorinated compounds, chlorine (37Cl/35Cl) isotope fractionation during diffusive/dispersive transport of organic contaminants in groundwater and to determine its consequences for source allocation and assessment of reactive processes using isotopes. The proposed research is based on the combination of high-resolution experimental studies, both at the laboratory (i.e. zero-, one- and two-dimensional systems) and at the field scales, and solute transport modeling. The project combines the expertise in the field of contaminant transport with the expertise on isotope methods in contaminant hydrogeology.

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

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.

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

Mercury threat in industrially impacted surface water bodies in Romania - integrated approach (MERCURO)

Mercury (Hg) is a persistent micropollutant presenting a substantial risk to the environment and an important threat to the human health. Past and present Hg contaminations of surface waters are thus of major concern due to the potential of Hg to accumulate in biota and magnify in the food chain. Therefore, the improved understanding of the relationship between Hg dispersion, distribution among sediments, particles, colloids and dissolved fractions, as well as accumulation and impact to biota is a prerequisite to fully assess the Hg threat to the aquatic systems and human health. By applying an integrated approach including a combination of field studies, laboratory analyses and numerical simulations, the present proposal aims to assess the impact of the Hg in the industrially impacted surface water bodies in Romania and to identify the possible threat on these resources The project focuses on River Olt basin, as one of the most impacted surface water body in Romania, altered by the cascade dam construction and under extensive past and present industrial activity. The Rm Valcea region comprises a high number of industrial companies including a large chlor-alkali plant (Oltchim), which is recognized as important point sources of Hg. A large array of hydro(geo)logical, physical, chemical, and ecotoxicological tools will be used to address the following key issues: - Performance of Hg survey and estimation the pollution extent in water and sediments; - Determination of the transport and dispersion of Hg in water column and sediments; - Improvement of the understanding on the behaviour of Hg associated to colloids, inorganic particles and organic matter; - Assessment of the bioaccumulation and effect of Hg to different organisms with emphasis on the primary producers in particular microalgae and macrophytes; - Evaluation of the food chain transfer and possible risks for the human health. The project will largely contribute to the understanding of mercury fate and impact in the contaminated systems and improved knowledge on complex processes governing the transfer and impact of Hg from the contaminated surface waters to humans. The project is also expected to contribute broadly to solving societal problems in Romania and to provide a scientific base for a sound definition of the existing problem and understand the causal chain, as well as it will help to develop efficient and cost-effective measures for protection. Strengthening the capacity, improving integration of scientists in the international network as well as developing 'best practices' for impact assessment of pollutants are other major outcomes of the project. They will be a significant step forward contaminant assessment in the entire Danube - Black Sea - Caspian Sea region, as it is a commonly accepted that historical industrial pollution from former communist times represents a significant threat for public health.

LEAD-ERA Ecomanindustry: Fostering industrial ecology and eco-efficiency in the manufacturing industry

Present concepts of industrial management are based on a linear value chain of products and services. Input materials such as raw materials, water and energy are transformed into products and by-products but cogenerating significant amount of wastes and polluting emissions. Cleaner production approach, focusing on single process efficiency within companies, and industrial symbiosis approach, focusing on systemic spatial resource efficiency among different companies, are both contributing to reduce the environmental impact of the industrial production. In this context, different tools to optimize industrial management have been developed, but none of them include both approaches. The aim of the present project is to combine both approaches in order to increase the overall resource efficiency of industrial processes within a system of different factories. Overall goal of the program Ecomanindustry: Development of a universal reproducible software based tool called CPIS for decision support integrating the existing experiences and methodologies of Cleaner Production (CP) and Industrial Symbiosis (IS). The CPIS-tool will facilitate inter-industrial assessment and communication for waste avoidance and reuse of materials based on the Software as a Service (SaaS) principles. Specific goals of the swiss partners: FHNW: FHNW will be the coordinator of the overall Project and lead field tests and case studies. FHNW will collect customer feedback on existing software and test user friendly and failure free functionality of a beta version of the developed CPIS-tool in a field test, and proof customer acceptance of the CPIS-tool application in two case studies. UNIL: UNIL will gather and valorize previous research and experiences of existing GIS-based decision support tools for the development of eco-industrial parks, design the concept, functionalities and boundaries of the software-based CPIS-tool, and choose the appropriate technologies to be implemented in the CPIS-tool. SOFIES: SOFIES will build a community of users and service provider, ensure the long term development of the CPIS-tool, promote the dissemination to other countries and elaborate adequate user guide and training to facilitate dissemination.

CAPAC (Climate And Pollution Analysis of Cairo)

The proposed project is the follow-up project of our present SNF-project CAPAC (Climate And Pol-lution Analysis of Cairo) phase one. Its main purpose is the finishing of the work begun in phase one in terms of methodology and data analysis. CAPAC is conducted by a doctorand, Miss Corinne Frey. CAPAC aims to combine in situ measurements of the energy balance with remote sensing tech-niques to parameterise urban and non-urban heat fluxes of the mega-city Cairo, Egypt and its surroundings. Cairo is located within a green north-south oriented strip of agricultural land and on the other hand between two desserts in the west and east. This makes the location of Cairo unique and very interesting for an urban climate study like this. Scientific objectives are the computation of very high resolution radiation and heat fluxes in urban areas under the conditions of spatial homogeneity/ heterogeneity of urban land cover. Very interesting is the analysis of how urban greens influence the urban heat fluxes and how the new suburbs of Cairo, which are expanding into the dessert explosively, will modify the local climate. The population of Cairo is growing several hundred thousand people per year. During the first phase of CAPAC a field campaign was conducted in Cairo. This data serve as calibration and validation of the remote sensing analysis. Following this campaign, algorithm development and data analysis will be the main task of the following months. This includes the analysis of the in situ measured flux data, as well as the evaluation of the estimated radiation and energy balance terms using ASTER and LANDSAT remotely sensed data. Main tasks in the determination of the radiation and energy balance terms using satellite data will be (1) the completion of the haze-removal-algorithm for the haze contaminated scenes, (2) the completion of the algorithm for estimation of the aerosol optical depth from satellite data and (3) to improve the S-Sebi method for the estimation of the Bowen-ratio or to find a better suited method for the estimation of heat fluxes. Another task, which is primarily related to quality control is the determination of the Bi-directional reflectance function (BRF) over Cairo using satellite data from CHRIS/PROBA, which are already acquired by the European Space Agency (ESA) on our demand. To substantiate the findings from Cairo another area of interest was chosen, namely Beer Sheva, Israel. Beer Sheva is located in the middle of the desert, offering a pure desert climate. There a small follow-up field campaign is planed together with Dr. Oded Potcher from Ben Gurion University in Beer Sheva.

European approach to nuclear and radiological emergency management and rehabilitation strategies (EURANOS)

Objective: The Integrated Project EURANOS, through the commitment of fifty operational emergency management organisations, 'stakeholder groups' and competent RTD institutes of many European countries who actively contribute to the following objectives, will build a fully interactive framework for initiating and promoting practical improvements of emergency management and rehabilitation strategies in Europe never reached before: (A) creating better communication links between those responsible for nuclear and radiological emergency management in European countries with the perspective of fast notifications, information exchange and interaction through more direct channels; (B) providing better coherence and transparency in decision processes on local, national and border crossing interventions as one input to improving public understanding and acceptance of off-site measures; (C) supporting decisions on effective and timely emergency actions and countermeasures in case of nuclear or radiological emergencies by access to reliable, consistent and comprehensive information, and in this way mitigating radiological and economic consequences; (D) developing a coherent framework for the sustainable rehabilitation of living conditions in contaminated areas by implementing integrated and decentralised approaches involving key stakeholders and the public. A common approach and an European perspective of a more harmonised emergency management and rehabilitation strategy on the local, national and supra-national levels will be created and promoted through common emergency exercises and their thorough evaluation together with all stakeholders involved and through 'stakeholder panels' on the key issues of rehabilitation. The common views on improved technical tools; methods, strategies and guidance will also create initiatives on the administrative and political levels to improve the efficacy of European emergency management and rehabilitation strategies.

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

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.

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

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.

Untersuchungen zur biologischen Funktion des Mykotoxins Zearalenon

Zearalenon ist ein nichtsteroides Mykotoxin mit östrogener Wirkung, das vorwiegend vom pflanzenpathogenen Pilzen wie Fusarium graminearum (Gibberella zea) und Fusarium culmorum gebildet wird. Infolge der von diesen Pilzen hervorgerufenen Krankeiten von wichtigen Kulturpflanzen, wie z.B. Ährenfusariose von Weizen und Kolbenfäule von Mais, kann es zur Kontamination von Lebensmitteln und Futtermitteln mit gesundheitsrelevanten Mengen des Mykotoxins kommen. Gegenwärtig ist völlig ungeklärt, ob die Fähigkeit zur Produktion von Zearalenon die Fähigkeit des Pilzes beeinflußt, als Pflanzenpathogen zu wirken. Es ist auch unbekannt, ob Zearalenon imstande ist, in bestimmte pflanzenphysiologische Vorgänge einzugreifen und es dadurch dem Pilz erleichtert, die Pflanze zu kolonisieren. Im Rahmen dieser Arbeit soll versucht werden, Voraussetzungen zur Beantwortung dieser Fragen zu schaffen: Durch die Einbringung des Reportergens GFP (Green Fluorescent Protein) in den pflanzenpathogenen Pilz Fusarium culmorum sollte es möglich werden, den Infektionsprozeß zu verfolgen und die Rolle von Zearalenon zu untersuchen. Durch Etablierung der REMI-Methode (Restriction Enzyme Mediated Integration) soll die Grundlage geschaffen werden, Insertionsmutanten von F. culmorum zu identifizieren, die nicht mehr imstande sind das Mykotoxin Zearalenon zu bilden.

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