Das Projekt "Handling of radium and uranium contaminated waste piles and other wastes from phosphate ore processing" wird/wurde gefördert durch: Euratom European Atomic Energy Community , Europäische Atomgemeinschaft. Es wird/wurde ausgeführt durch: Öko-Institut. Institut für angewandte Ökologie e.V..
Das Projekt "Immobilisation of arsenic in paddy soil by iron(II)-oxidizing bacteria" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Tübingen, Institut für Geowissenschaften, Zentrum für Angewandte Geowissenschaften.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.
Das Projekt "Effect of diffusive/dispersive processes on stable isotope ratios of organic contaminants in aquifer systems" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Technical University of Denmark, Department of Environmental Engineering.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.
Das Projekt "Steady-State Dilution and Mixing-Controlled Reactions in Three-Dimensional Heterogeneous Porous" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Eberhard Karls Universität Tübingen, Zentrum für Angewandte Geowissenschaften (ZAG), Arbeitsgruppe Hydrogeology.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.
Das Projekt "Microbial processes and iron-mineral formation in household sand filters used to remove arsenic from drinking water in Vietnam" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Tübingen, Zentrum für Angewandte Geowissenschaften (ZAG), Arbeitsgruppe Geomikrobiologie.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.
Das Projekt "LEAD-ERA Ecomanindustry: Fostering industrial ecology and eco-efficiency in the manufacturing industry" wird/wurde gefördert durch: Bundesamt für Umwelt. Es wird/wurde ausgeführt durch: Fachhochschule Nordwestschweiz, Hochschule für Life Sciences, Institut für Ecopreneurship.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.
Das Projekt "Effectiveness of low emission zones: Large scale analysis of changes in environmental NO2, NO and NOx concentrations in 17 German cities" wird/wurde gefördert durch: Europäische Forschungsvereinigung für Umwelt und Gesundheit im Transportsektor EUGT e.V.. Es wird/wurde ausgeführt durch: Evonik Industries AG.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
Das Projekt "Integrated air quality sensor for energy efficient environment control (INTASENSE)" wird/wurde gefördert durch: Kommission der Europäischen Gemeinschaften Brüssel. Es wird/wurde ausgeführt durch: C-Tech Innovation Ltd..Objective: Space heating accounts for more than 50Prozent of the energy consumption of public & residential buildings, and reduction of this energy demand is a key strategy in the move to low energy/low carbon buildings. The careful management of air flow within a building forms part of this strategy through the control of inlet fresh air and exhaust air, maximising air re-circulation, and minimising the amount of fresh air which is often drawn in through a heat exchanger. However, there is a high risk that the air quality is reduced. Continued exposure to environments with poor air quality is a major public health concern in developed and developing countries. It is estimated that the pollutants responsible for poor air quality cause nearly 2.5 million premature deaths per year world-wide. Significantly, around 1.5 million of these deaths are due to polluted indoor air, and it is suggested that poor indoor air quality may pose a significant health risk to more than half of the world's population. Perhaps surprisingly, remedial action to improve air quality is often easy to implement. Relatively simple measures such as increased air flow through ventilation systems, or a greater proportion of fresh air to re-circulating air are sufficient to improve air quality. Low-energy air purification and detoxification technologies are available which will reduce the concentration of specific pollutants. Similarly, filtration systems (e.g. electrostatic filters) can be switched in to reduce the level of the particulate matter in the air (the principle pollutant responsible for poor health). The INTASENSE concept is to integrate a number of micro- and nano-sensing technologies onto a common detection platform with shared air-handling and pre-conditioning infrastructure to produce a low-cost miniaturised system that can comprehensively measure air quality, and identify the nature and form of pollutants. INTASENSE is a 3-year project which brings together 8 organisations from 5 countries.
Das Projekt "Antimony leaching from contaminated soil under different water regimes" wird/wurde gefördert durch: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Es wird/wurde ausgeführt durch: Eidgenössische Technische Hochschule Zürich, Institut für terrestrische Ökosysteme, Ökosystemmanagement.Antimony (Sb) is a rather rare element in the earth's crust, but in the recent past, human activities have led to highly elevated Sb concentrations in soils and sediments at many locations and, as a consequence, to increased exposure of biota to this toxic element. Soil contamination by Sb has recently become an urgent issue in particular on shooting ranges. In Switzerland, all shooting ranges are currently examined and will be remediated within the next decade. This implies the removal of large quantities of contaminated soil. Large fractions of these soils are not heavily contaminated but have to be treated because they are located in pollution-sensitive areas such as groundwater protection zones. This soil can potentially be reused for less sensitive types of land-use, saving high treatment costs and precious hazardous waste disposal space. Knowledge about the risks of Sb leaching from such soils is very limited, however. One key factor regarding solute leaching is the water regime, particularly in soils subject to permanent or periodic water-logging. Water-logging strongly inhibits soil aeration, and this can have a strong influence on the entirety of chemical and biological conditions affecting solute transport in soil. This holds all the more for elements that are sensitive to changes in their oxidation state under environmental conditions such as Sb. Given that there is very little information available on the transport behavior of Sb in soils, particularly under dynamic water regimes, this project has the aim to investigate the influence of water-logging on Sb leaching from contaminated soil. For this purpose, we carry out experiments with a relocated shooting range soil as well as with a comparable synthetic soil in order to identify and model the role of sorption and redox processes on Sb mobilization and leaching. Special attention will be given to the speciation of Sb in the soil solution. The results will be relevant beyond providing a scientific basis for the risk assessment of Sb leaching from contaminated soil, as it will also further the mechanistic understanding of how water-logging affects the transport of redox-sensitive solutes in soils in general.
Das Projekt "Implications of the biogenic character on aquatic food chain accumulation of elemental selenium" wird/wurde gefördert durch: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Es wird/wurde ausgeführt durch: Fachhochschule beider Basel - Nordwestschweiz.Selenium is a double edged chemical element, since it is both essential yet highly toxic. Besides its high acute toxicity, selenium is characterized to be strongly bioconcentrated from dissolved selenium species (selenite, selenate, selenoaminoacids) in aquatic primary producers and further biomagnified during food chain transfer. In consequence, water borne selenium concentrations of as little as 2 myg / L have been documented to cause severely adverse effects on top predators such as water birds and fish. Although the ecotoxic impact was first noticed in the early 1980s, to date no definitive solution has been found to remediate selenium contaminated drainage and waste waters. Due to the water insolubility of elemental selenium, the dogma that 'elemental selenium is not bioavailable and not toxic' dominates current scientific literature and forms the basis for various remediation approaches using microorganisms to convert selenium oxyanions to elemental selenium. However, a number of considerations and recent studies suggest that the dogma might only be true for 'bulk' elemental selenium, yet not for microbially formed, so called biogenic selenium. Biogenic differs from bulk elemental selenium considerably regarding its physico-chemical properties. Biogenic elemental selenium consists of nanometer sized spheres, which do not crystallize to larger particles of trigonal elemental selenium, the thermodynamically stable allotrope. The latter is due to stabilization by proteins associated with the particles. As a consequence, biogenic elemental selenium does not settle yet remains in waters as a colloidal suspension, thus being subject to uptake by biota. Although the general bioavailability of biogenic elemental selenium has been proven, it has not been studied in detail, in particular not in aquatic environments. We aim at quantifying acute and chronic toxicity in the model organism Daphnia magna, elucidating the underlying mechanism of toxicity. Furthermore, we will quantify biogenic elemental selenium uptake, depuration and biotransformation to proteinous forms (the species most relevant for trophic transfer). Thus we will be able to deliver an improved model of selenium food chain transfer in aquatic environments, the basis for appropriate selenium risk assessment. During the course of the proposed research, such questions as the following will be answered: - Is biogenic elemental selenium bioavailable and / or toxic to Daphnia magna? Which are the mechanisms underlying toxicity? - To which extent is biogenic selenium biotransformed to proteinous (highly bioaccumulative) species? Does biogenic elemental selenium represent a significant entrance port for selenium at base of aquatic food chain?
