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Ökologische Bewertungskriterien für Desinfektionsmittel und deren Adaptierung in der Desinfektionsmittel-Datenbank der Stadt Wien

Das Projekt ÖkoKauf der Stadt Wien hat es sich zum Ziel gesetzt, durch die Erstellung von ökologischen Kriterien, Pilotprojekte und durch Bewusstseinsarbeit das Beschaffungswesen im Magistrat Wien weiter zu ökologisieren. In diesem Rahmen widmete sich der Arbeitskreis 'Desinfektionsmittel unter der Leitung der Wiener Umweltanwaltschaft (WUA) der Aufgabe, für Hygienefachleute ein Instrument zur Beurteilung der Auswirkungen von Desinfektionsmitteln auf Gesundheit und Umwelt zu erstellen. Das Österreichische Ökologie-Institut führte eine Daten- und Literaturrecherche durch, das Umweltbundesamt nahm ergän-zende ökotoxikologische Tests an Wirkstoffen und -produkten vor und 'die umweltberatung ermittelte stationsbezogene Desinfektionsmittelverbräuche in Wiener Krankenanstalten. Die Recherche- und Testergebnisse zu Desinfektionsmittelwirkstoffen und -produkten wurden in einer vom IFZ konzipierten und von der Magistratsabteilung 14 realisierten Datenbank zusammengefasst. Um die ökotoxikologischen Produkteigenschaften vergleichbar zu machen, wurde vom IFZ ein Bewertungsraster entwickelt und in die Datenbank integriert. Dabei werden nachteilige Wirkungen auf die Gesundheit anhand von vier Wirkungskategorien erfasst: Akute Giftigkeit; Reizwirkung auf die Haut; Sensibilisierung, allergenes Potenzial sowie Erbgutschädigende, krebserzeugende und fruchtschädigende Eigenschaften. Zusammen mit der Berücksichtigung des Verhaltens in Oberflächengewässern (Abbauverhalten, Bioakkumulationspotenzial, Toxizität für Wasserorganismen) sowie dem Verhalten in Kläranlagen werden insgesamt sechs Bewertungszahlen generiert, die auf einer Skala von 1 (vernachlässigbar) bis 5 (sehr hoch) das gesamte Gefährdungsprofil des Stoffes beschreiben sollen. Das Gefährdungsprofil eines Handelsproduktes errechnet sich aus den Gefährdungsprofilen der darin enthaltenen Wirkstoffe anhand eines Algorithmus: Dabei wird die Annahme getroffen, dass die Produkteigenschaften von der Konzentration der darin enthaltenen Wirkstoffe abhängen. Bei der Bewertung ist außerdem zu gewährleisten, dass ein Wirkstoff mit einem hohen Gefährdungspotenzial angemessen berücksichtigt wird, auch und gerade wenn seine Konzentration im Produkt gering ist. In der Literatur wird dazu eine logarithmische Skalierung vorgeschlagen. Die Bewertung berücksichtigt derzeit die Wirkstoffe sowie Anwendungsverdünnungen. Die Zusammenfassung der Produkte in Verwendungs- bzw. Expositionskategorien ermöglicht letztlich eine vergleichende Bewertung. Da das Bewertungsraster gerade auf eine vergleichende Bewertung von Produkten abzielt, unterliegt er einer ständigen kritischen Diskussion, die auch häufig von den Herstellern geführt wird. Dieser Umstand sowie das Faktum von Produktlebenszyklen erfordern ein ständiges Update der in der Datenbank enthaltenen Informationen und eine Anpassung des Bewertungsmodells an den aktuellen Stand von Forschung sowie Standards der Stoff- und Produktpolitik.

High Elevation Treeline Research

If one considers the high elevation treeline as a global phenomenon, many local drivers, which dominated the debate in the past, become less significant, they become modulators of a more fundamental, common cause. Our working hypothesis is that the major driver of treeline formation is the ability to form new structures, rather than the provision of raw materials for these structures. In other words, we suggest that the treeline is a sink (growth) rather then a source (photosynthesis) driven phenomenon, with temperature representing the single most important determinant. We do not question the influence of other factors, but we consider them to represent a suite of regional peculiarities, which may affect the actual position by not more then 100 m in elevation. A detailed discussion of the treeline issue can be found in: Our activities go in several directions. They include treering studies across the treeline ecotone (see ref. below), microclimate measurements at various latitudes and an assessment of the carbohydrate supply status at the tree limit. The worldwide treeline temperature assessment nears its end by 2001, when year-round data from ca. 30 different treeline sites around the globe will be available. As a standard procedure we measure root-zone temperature at 10 cm depth in the shade of tree crowns at the treeline using Tidbit (Onset Corp.) data loggers. Currently available data from 90 % of the stations average at seasonal mean ground temperatures of ca 6.5 C, with very little site to site variation, irrespective of latitude (minimum of 5.5 C on Mexican volcanos at 4000 m and maximum at some maritime temperate zone treelines of ca 7.5 C). The seasonal mean proved to be a better predictor of treeline position than warmest month temperatures or a suite of thermal sums tested. There are regions with no suitable treeline taxa where natural treelines occure at lower elevations (higher temperatures; e.g. Hawaii). In a work on carbohydrate pools we compare treelines in Mexico, the central Alps and in N-Sweden (Abisko). We see no decline of reserves as one approaches the existential limit of trees, in fact, carbohydrate and lipid stores reach a maximum at tree limit. Thus, it seems unlikely that carbon limitation is a cause of treeline formation.

Patterns of evolution in the species complex of the tree-root endophyte Phialocephala fortinii

Populations of P. fortinii from allover Europe are examined using microsatellites to construct gene genealogies and infer evolutionary history. The tree-root endophyte Phialocephala fortinii s.l. (mitosporic Ascomycota) is the dominant colonizer of conifer root systems in forests in the northern hemisphere. P. fortinii s.l. is genetically highly diverse and forms a complex of several cryptic species. Recombination occurs or has occurred within cryptic species and to some extent also among them (introgression). Cryptic species occur sympatrically and they can form large thalli, but it remains unclear whether the observed patterns of spatial distribution reflect local climax situations or are the results of recent gene and genotype flow. One of the key objectives will be to estimate population genetic parameters (eg. migration rates, genotype flow, recombination) within and among populations of cryptic species in forests where man-mediated genotype flow can be excluded. Other key objectives are the determination of the number, frequency, distribution and evolutionary history of the cryptic species in Europe and to identify the driving forces for speciation. The approach will be multidisciplinary and will include standard mycological and microbiological methods as well as molecular genetic techniques such as microsatellite fingerprinting and DNA sequencing. The evolutionary history of haplotypes at both the population and species level will be reconstructed and the results will be compared with known patterns of pleistocenic glaciations and postglacial recolonization of host trees. The project will be a significant contribution to the understanding of the population and evolutionary genetics of a versatile and ecologically extremely successful fungal genus and it will shed light on the effects of pleistocenic and postglacial climatic changes on fungal speciation.

Competence network for genome research on bacteria for the environment, agriculture, and biotechnology, Cluster C. glutamicum (at Bielefeld University); the regulation of phosphate metabolism in C. glutamicum and lipid synthesis: The identification of regulators and regulatory metabolites

Phosphorous (P) is an essential component of all cells. P assimilation occurs mainly in the form of phosphate via the reactions of the energy and carbon metabolism. Therefore, the P metabolism is closely intertwined with the energy and the central carbon metabolism: only with sufficient P supply an optimal energy and carbon metabolism is possible. As the latter generates precursor metabolites for the biosynthesis of amino acids, the interplay of P and C metabolism is of particular importance in amino acid producing Corynebacterium glutamicum. The Institute of Biotechnology 1 at the Research Center Jülich successfully worked on the biochemical and genetic characterisation of the main amino acid biosynthesis pathways in C. glutamicum as well as on the central carbon metabolism. Moreover, using nuclear magnetic resonance (NMR) studies and stable isotope labeling techniques, in vivo activities of single enzymes and pathways were quantified. These informations were used to optimize amino acid production with C. glutamicum (metabolic design, Sahm et al. 2000). Within the project, the P metabolism and its regulation shall be characterized in depth using the genome sequence of C. glutamicum. The phosphate stimulon of C. glutamicum will be defined using DNA microarray technology. Among this group of genes showing differential expression in dependence of phosphate availability, genes of the energy and central carbon metabolism will be of particular interest. In Jülich, the equipment for the generation and application of DNA microarrays is available as well as expertise to use this key technology for genome-wide expression analyses in E. coli (Zimmer et al. 2000). A parallel approach will focus on unraveling the molecular mechanism(s) of phosphate regulation with particular emphasis on two-component regulatory sytems, which in E. coli and B. subtilis play central roles in this regulation. Regarding the analysis of genetic regulatory mechanisms, extensive experience has been gained for the genetic and biochemical characterization of two-component sytems in enterobacteria (Kaspar et al. 1999).

Pre-normative work on sampling and testing of solid biofuels for the development of quality assurance systems ('BioNorm')

The goal of the EU funded BioNorm project is the development of an integrated quality assurance system for the overall provision chain of solid biofuels. Therefore, methods for sampling and sample reduction as well as for the determination of physical/mechanical (e.g. moisture content, ash melting behaviour, particle size distribution) and chemical properties (elemental concentration) of solid biofuels will be investigated and improved. The project work is divided into 6 work packages where 39 partner institutions (together with 15 subcontractors) from 20 European countries (also partners from the Newly Associated States - 'NAS' participate) co-operate. Work package III of the project is concerned with chemical tests and is subdivided into two tasks which are Task III.1 'Determination of sulphur, chlorine and nitrogen and Task III.2 'Determination of major and minor elements. Correct sulphur, chlorine and nitrogen measurements for a wide scope of solid biofuels are needed for secure operation and high availability of biomass combustion and gasification plants (deposition and corrosion aspects) as well as regarding emission reduction and emission regulations (SOx, HCl, PCDD/F, NOx emissions). The correct determination of major and minor elements in biofuels is also of great importance. Major ash forming elements (Al, Si, K, Na, Ca, Mg, Fe, P, Ti) are of key relevance regarding ash melting, deposit formation and corrosion during thermal biomass conversation. Minor elements (As, Ba, Cd, Co, Cu, Cr, Hg, Mo, Mn, Ni, Pb, V, Zn) are of key relevance in respect to particulate emissions as well as the environmental evaluation of the ashes formed and their further utilisation. No quality assurance standards for the determination of these elements in biofuels exist so far. Available test procedures are derived primarily from analyses of coal and are partly not applicable for solid biofuels. Therefore, the objectives of this work package are to test, evaluate and validate determination methods for these elements. For this purpose different promising digestion and measurement methods, applied on several biofuels (among others a wood-bark mixture and straw), will be tested. The most promising method(s) will be optimised and validated on an element by element basis. Based on the outcome of the investigations best practise guidelines for the correct measurement of S, Cl, N as well as of major and minor elements in solid biofuels will be developed. This guidelines will form the basis for the compilation of draft CEN standards.

Ice2sea - estimating the future contribution of continental ice to sea-level rise (ICE2SEA)

Objective: The melting of continental ice (glaciers, ice caps and ice sheets) is a substantial source of current sea-level rise, and one that is accelerating more rapidly than was predicted even a few years ago. Indeed, the most recent report from Intergovernmental Panel on Climate Change highlighted that the uncertainty in projections of future sea-level rise is dominated by uncertainty concerning continental ice, and that understanding of the key processes that will lead to loss of continental ice must be improved before reliable projections of sea-level rise can be produced. The ice2sea programme will draw together European and international partners, to reduce these uncertainties. We will undertake targeted studies of key processes in mountain glacier systems and ice caps (e.g. Svalbard), and in ice sheets in both polar regions (Greenland and Antarctica) to improve understanding of how these systems will respond to future climate change. We will improve satellite determinations of continental ice mass, and provide much-needed datasets for testing glacier-response models. Using newly developed ice-sheet/glacier models, we will generate detailed projections of the contribution of continental ice to sea-level rise over the next 200 years, and identify thresholds that commit the planet to long-term sea-level rise. We will deliver these results in forms accessible to scientists, policy-makers and the general public, which will include clear presentations of the sources of uncertainty. The ice2sea programme will directly inform the ongoing international debate on climate-change mitigation, and European debates surrounding coastal adaptation and sea-defence planning. It will leave a legacy of improved understanding of key cryospheric processes affecting development of the Earth System and the predictive tools for glacier-response modelling, and it will train a new generation of young European researchers who can use those tools for the future benefit of society.

Health effects of indoor pollutants: integrating microbial, toxicological and epidemiological approaches (HITEA)

Objective: Healthy housing and good indoor air quality are important goals of public health. However, biological indoor pollution due to dampness, moisture and mold is an emerging environmental health issue, as recognized in EU indoor air policy documents. Prevalence of dampness is remarkable, and may still increase due to demands of energy savings and extreme weather periods and floods associated with climate change. The exposure may lead to long-term impacts such as asthma. The documentation is strong on association between building mold and health, but the causative agents and disease mechanisms are largely unknown, which impedes recognition of a mold-affected patient in health care. Efficient control and regulation are hampered by the insufficient understanding of these causalities. Understanding of the links between building practices and health is lacking. There is an urgent need for European-wide knowledge to form a basis for establishing building-associated criteria for healthy indoor environments. The aim of this proposal is to clarify the health impacts of indoor exposures on children and adults by providing comprehensive exposure data on biological and chemical factors in European indoor environments.

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Neogene Paleoenvironmental changes in the McMurdo Sound region: High resolution chemical and sedimentological analysis of Miocene (ca17 Ma) to Pleistocene sediments from ANDRILL Site SMS

At ANDRILL site SMS (Southern McMurdo Sound) an longer than 1000m sediment core will be drilled from a sea-ice platform covering Early/Middle Miocene (ca17 Ma) to Pleistocene strata of McMurdo Sound, Ross Sea, Antarctica. The target sediments were deposited on the western flank of the Victoria Land Basin (VLB), a structural half-graben that forms part of the West Antarctic Rift system, and experienced subsidence since late Eocene times. On this sediment core we propose to combine high-resolution on-ice measurement of chemical element concentrations using XRF core-scanner with off-ice high-precision chemical and sedimentological analysis on bulk samples (XRF, XRD, ICP-MS, biogenic components) and individual lithoclasts (LA-ICP-MS, electron microprobe, microscopy). The resulting multiple dataset will provide detailed information on sediment composition and, thus, contribute to several scientific objectives of ANDRILL such as the history of Ross/West Antarctic ice shelf expansion and retreat since ca17 million years, sea-ice presence/absence in the McMurdo region, and the history of Neogene sediment provenance and accumulation rates in the VLB. Our major goal is to improve our understanding of the Neogene paleoenvironmental evolution of Antarctica with a special focus on the Mid-Miocene climatic optimum (ca17-15 Ma) and the subsequent onset of major cooling (ca14 Ma) along with the key question on the stability of cold-polar climate conditions during the last 14 million years

Optimized Strategies for Risk Assessment of Chemicals based on Intelligent Testing (OSIRIS)

The proposed regulation concerning the registration, evaluation, authorisation and restriction of chemicals (REACH) requires demonstration of the safe manufacture of chemicals and their safe use throughout the supply chain. There is therefore a strong need to strengthen and advance human and environmental risk assessment knowledge and practices with regard to chemicals, in accord with the precautionary principle. The goal of the project OSIRIS is to develop integrated testing strategies (ITS) fit for REACH that enable to significantly increase the use of non-testing information for regulatory decision making, and thus minimise the need for animal testing. To this end, operational procedures will be developed, tested and disseminated that guide a transparent and scientifically sound evaluation of chemical substances in a risk-driven, context-specific and substance-tailored (RCS) manner. The envisaged decision theory framework includes alternative methods such as chemical and biological read-across, in vitro results, in vivo information on analogues, qualitative and quantitative structure-activity relationships, thresholds of toxicological concern and exposure-based waiving, and takes into account cost-benefit analyses as well as societal risk perception. It is based on the new REACH paradigm to move away from extensive standard testing to a more intelligent, substance-tailored approach. The work will be organised in five interlinked research pillars (chemical domain, biological domain, exposure, integration strategies and tools, case studies), with a particular focus on more complex, long-term and high-cost endpoints. Case studies will demonstrate the feasibility and effectiveness of the new ITS methodologies, and provide guidance in concrete form. To ensure optimal uptake of the results obtained in this project, end-users in industry and regulatory authorities will be closely involved in monitoring and in providing specific technical contributions to this project.

Coexistence of different functional types of indigenous trees of the Munessa Forest, Ethiopia: Carbon, water and nutrient relations

Ecophysiological traits (carbon, water and nutrient relations) allowing for the coexistence of different functional types (life-forms) of indigenous trees in Munessa Forest, Ethiopia is proposed. Above and below ground resource acquisition and utilization by Croton macrostachys (facultative deciduous), Podocarpus falcatus (evergreen gymnosperm) and Prunus africana (broad-leafed evergreen) will be investigated as influenced by site conditions and season. In addition to tree growth and canopy characteristics, photosynthesis, respiration and transpiration at different zones of tree crowns will be recorded. Whole-tree transpiration will be followed using the Granier stem-flux system. Partitioning of soil water among the trees will be assessed using 18O/16/O-signatures of xylem sap and of soil water collected from different depths. Seasonal water use of juvenile and adult trees will be compared and the seasonal patterns of fine root biomass production shall be analyzed. Data on nutrient relations, mycorrhizal networks and silvicultural characteristics of the trees, produced by the other collaborating groups will be integrated to explain the coexistence of the three functional types of trees. It is expected that species-specific requirements and strategies of survival and growth of the investigated tree species can be used for an ecologically sound reforestation program of a mixed forest.

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