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.

Inhalt

I Presentations.- Natural Versus Anthropogenic Emissions of Trace Metals to the Atmosphere.- Technological Parameters Affecting Atmospheric Emissions if Trace Elements from Major Anthropogenic Sources.- Control of Heavy Metal Emissions from Waste Incinerators.- A Tiered-Profile Approach to a Global Trace Metal Emission Inventory.- Modelling the Atmospheric Transport of Trace Metals from Europe to the North Sea and the Baltic Sea.- Elemental Source-Receptor Techniques for Precipitation and Aerosol: Recent Experiences from Narragansett, Rhode Island.- On the Spatial Representativeness of Trace Element Ratios.- Statistical Methods to Apportion Heavy Metals.- Dry Deposition of Trace Elements.- Wet Deposition of Heavy Metals.- Behavior of Cd, Mn, and Pb in Forest - Canopy Throughfall.- Analytical Techniques for Atmospheric Trace Elements.- Cycling of Mercury in the Environment with Enphasis on the Importance of the Element in Acid Rain Studies.- Atmospheric Transformations of Trace Metals: Evidence for Aerosol Sulfur Association with Metals from Soil Minerals in Eastern North America and the Potential for Solubilization of Aluminium and Iron Before Deposition from the Atmosphere.- Biomonitors of Air Pollution by Heavy Metals.- II Working Group Summaries.- Technology Related to Sources of Heavy Metals and the Abatement Thereof.- Modelling Trace Element Transport.- Research Needs in Understanding Processes of Transformation, and Dry and Wet Deposition of Atmospheric Metals.- Special Topics Concerning Interactions of Heavy Metals with the Environment.