Das Projekt "Der Einsatz terrestrischer Modell-Oekosysteme zur Abschaetzung von Umweltrisiken in Oekosystemen" wird vom Umweltbundesamt gefördert und von ECT Ökotoxikologie GmbH durchgeführt. The objective of the intended research project is to improve the hazard and risk assessment for chemicals by taking into account the complexity of ecosystems. To achieve this aim effects and fate of a selected chemical substance will be investigated in a terrestrial model ecosystem (TME). A TME consists of an encased intact soil-core which will be extracted from Euro-soil sites and stored under controlled environmental conditions. Euro-soils are representative for a wide range of soils found within the EU. Typical Euro-soils sites have been identified by the EU in five different countries (Greece, Italy, France, Great Britain, Germany) and will be used for the intended research project. Qualified institutions located close to the Euro-soil sites will become partners in the project. Site specific end-points as well as end-points common for all sites will be derived from field studies conducted on Euro-sites simultaneously with the TME studies. Beyond the expected scientific achievements of the intended project acceptance from supranational organizations (eg OECD) will be sought in order to implement the ring-tested and validated TME as a standardized guideline in the risk assessment procedure for chemicals.
Das Projekt "Die Nutzung terrestrischer Oekosysteme (TMEs) fuer die Bewertung von Umweltrisiken in Oekosystemen" wird vom Umweltbundesamt gefördert und von ECT Ökotoxikologie GmbH durchgeführt. The project is designed to improve hazard and risk assessment of chemical contaminants in soil at the ecosystem level using terrestrial model ecosystems (TMEs). TMEs consist of encased intact (non-homogenized) soil-cores that are extracted from field sites with the minimum of disturbance to the natural vegetation, soil microflora and fauna, and the layering of the soil inside the cores. The size of a soil-core will be between 17 and 20 cm in diameter and between 30 and 60 cm in depth. Parameters such as biological diversity and activity, cycling of essential elements, biodegradation of organic matter, biodegradation and accumulation of xenobiotic substances will be investigated to integrate structural and functional aspects of the soil environment. A key feature of the TME assemblage is that it allows determination of the potential fate and ecological effects of test substances in a replicated system of soil-cores. Four different soil types, representative of defined 'Euro-soils', will be used as terrestrial ecosystems in a ring-test performed by four participating European laboratories. Initially, the selected sites will be surveyed for species composition, and checked for homogeneity prior to soil-core extraction. After preparing the TME equipment and establishing the methods for measuring the various end-points a pre-test with a selected test substance will be performed. The test substance will be chosen after consultation and agreement with national and international competent authorities (eg Joint Research Centre, European Chemicals Bureau; Federal Environmental Agency of Germany) who are responsible for environmental risk assessments of existing and new chemicals. Based on the experience gained in the pre-test the TME main-test will be conducted in the following year in combination with a field study to validate the results from the TME test.Three treatment levels will be used, one of which is close to the predicted environmental concentration, one of which is 5 to 10 times higher and the control. After application of the test substance the test period will be at least 12 weeks and can be extended to one year. In order to minimize inter-laboratory variation, strict harmonization of equipment and experimental procedure will be rigorously applied and individual laboratories will handle certain designated tasks for all participants. The TME project firstly will provide improved effect data which help to evaluate single-species test results; secondly, experimentally gained fate data will allow significantly improved fate assessments; thirdly, the data gained on ecosystem functioning, which has been neglected so far in the environmental risk assessment of chemicals, may reveal indirect as well as synergistic or compensatory effects of a test substance at ecosystem level. The innovative step of the project will be to field-validate and ring-test the TME which is necessary before it can be integrated within ecologically relevant risk assessment