Das Projekt "Verringerung der Ozonbildung in der Troposphaere in Europa durch die Verwendung alternativer industrieller Loesungsmittel" wird vom Umweltbundesamt gefördert und von Universität-Gesamthochschule Wuppertal, Fachbereich 9 Naturwissenschaften II, Physikalische Chemie durchgeführt. General Information: Photochemical air pollution is a serious environmental problem for many regions of Europe during the summer months. The atmospheric degradation of volatile organic compounds (VOCs) in the presence of nitrogen oxides (NOX) leads to the production of a range of harmful secondary pollutants such as ozone and peroxy acylnitrates (PAN). Ozone formation is of particular concern since it is known to have adverse effects on human health, vegetation, a variety of materials and is also a greenhouse gas Solvents constitute around 35 per cent of the total VOC emissions in Europe and hence are a major contributory factor to oxidant formation. Chemical industries in the United States and Europe have now recognised that a switch from traditional solvents (aromatic and unsubstituted hydrocarbons and chlorocarbons) to oxygenated compounds is inevitable, both in terms of toxicity problems and to reduce the levels of oxidant formation in the troposphere. Indeed it has been estimated that if it were possible to replace all existing solvents by acetone, a reduction in ozone formation potential of around 75 per cent would result. Hence, the potential importance of switching from traditional solvents to oxygenated compounds in control strategies for VOC emissions is clearly apparent. Thus it seems that replacement of many existing solvents will occur in the near future and that esters, glycol ethers and di-ethers will form a significant proportion of these future solvents. The purpose of this programme is to provide a scientific evaluation of oxidant formation arising from the use of these new solvent types. In particular, it is believed that scientifically based evaluations of the ozone formation potentials of these species will contribute to a cost-effective ozone control programme in Europe. It is proposed to organise an extensive research programme in which basic mechanistic studies on the atmospheric behaviour of generic esters, glycol ethers and di-ethers in real air mixtures under a variety of different VOC compositions and NOx concentrations will be carried out. The aim of this project is to set up a general mechanism using all available kinetic and product distribution data for incorporation into a photochemical trajectory model specifically designed for European conditions. The results should provide answers to the following key questions must be addressed prior to selection and deployment of new solvent types: - Does the use of an alternative solvent lead to a reduction in tropospheric ozone formation? - How does the solvent affect the chemistry and transport of NOy in the troposphere? - Are there any products arising from the atmospheric degradation of the solvent that have other potential environmental impacts? Prime Contractor: University College Dublin, Department of Chemistry; Dublin/Ireland.