Das Projekt "Optimized Strategies for Risk Assessment of Chemicals based on Intelligent Testing (OSIRIS)" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum für Umweltforschung GmbH - UFZ, Department Ökologische Chemie durchgeführt. 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.