Control and Fate of Atmospheric Trace Metals

The increasing production of industrial goods, heat, and energy, as well as traffic, has led to the release of considerable amounts of toxic trace metals to the atmosphere. The result is elevated concentrations of toxic metals in local populations and eco- systems. Recently the problem of atmospheric long-range transport of trace metals has also been recognized. Significant amounts of these pollutants are disposed and deposited both on regional and global scales. In the atmosphere they may influence the chemical reactions. Of particular interest is their catalytic effect on the oxidation prosesses taking place in water droplets or on the surface of wet particles (e. g. the oxidation of sulphur dioxide to sulphate), however, the main environmental impact starts when the atmospheric trace metals are deposited on ground and vegetation and subsequently brought into the water circulation. During the later years significant progress has been made in the development of equipment to reduce and control the atmospheric emissions of toxic trace metals. This particularly applies to electrostatic precipitators and wet scrubbers for the collection of fine particles. The main objective of the workshop was to survey present knowledge concerning the sources, atmospheric fluxes, sinks and chemical impact of the atmospheric trace metals, and to review the developments of emission control equipment and the perspectives to reduce the potential risks from toxic metals. During the first two days of the meeting, 15 invited review papers were presented.