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The chemistry of ground level atmospheric ozone formation is highly complex and nonlinear and has many uncertainties. As a result no chemical model can be relied upon to give accurate predictions unless it has been evaluated by comparison with experimental data. There are essentially two ways in which a photochemical oxidant model can be evaluated. One compares the predictions of the complete model against field data taken during a historic ozone pollution episode. Another approach relies on the evaluation of individual pollutant compounds, separately. In the case of gas-phase chemical mechanisms, this means evaluating the predictions of the mechanism against results of environmental chamber experiments (Carter ., 1995a).

Atmospheric chemistry has not yet been fully understood. One of the main reasons is the complex interaction between components of the gas phase and of the condensed phases. In this contribution we would like to consider, by example of the reaction between aqueous SO and molecular oxygen, occurring in the presence of nitrate, some aspects of such aninteraction which may be of interest both to the researchers and modellers of cloud chemistry.

Isoprene is a conjugated diene (2-methyl-buta-1,3-diene), volatile and hardly soluble in water; under normal pressure it boils at 34 °C (Merck, 1999) and dissolves up to 1.47x10 M at 21.5 °C, with a Henry’s constant of 0.027 mole kg atm at 25 °C (NIST, 2001). Isoprene is a metabolite in plants, microbes, animals and humans, and a major biogenic trace compound emitted to the atmosphere. It is very reactive towards atmospheric gas-phase oxidants such as hydroxyl and nitrate radicals or ozone. At higher concentrations, 220 – 7000 ppm, it is carcinogenic to rodents and possibly carcinogenic to humans (Melnick and Sills, 2001).

Once released into the atmosphere, primary diesel emissions (or any other direct emissions) are subject to dispersion and transport and, at the same time, to various physical and chemical processes, which determine their ultimate environmental fate. To elucidate potential health effects of diesel exhaust, it is insufficient to characterize only the primary pollutants that are directly emitted from diesel vehicles. Secondary compounds, formed during the transport of emissions through the atmosphere, may also affect human health.

Emissions from the combustion of fossil fuels, especially road traffic emissions, are major contributors to air pollution. Though exhaust-cleaning techniques for vehicles have been significantly improved during the last years and the averaged fuel consumption per single vehicle has significantly decreased, the contribution of road traffic emissions to tropospheric photosmog formation is still high, due to the increasing total number of vehicles.

The ability of Europe’s research teams to remain at the forefront of all fields of science and technology depends on their being supported by state-of-the-art infrastructures. The term “research infrastructures” refers to facilities and resources that provide essential services to the research community in both academic and/or industrial domains.

Historically, some of the new EU Member States and the Candidate Countries have experienced high levels of pollution in the past. Enhanced management measures were and are needed to improve their air quality. A survey was recently conducted (Batchvarova ., 2005) to list the current research activities on atmospheric chemistry in these counties, as well as the groups and institutions involved in it. Air chemistry is an essential element of air quality, climate change modelling, industrial energy planning, and health risk assessments. Atmospheric chemistry research is also related to air quality monitoring. Therefore, the survey has also retrieved information on air quality monitoring networks and their management of those countries involved. Some information on air pollution modelling research is also discussed.

Non-methane volatile organic compounds (NMVOC) were measured at various sites representing different areas and different emission sources in the city of Wuppertal, Germany. The measurements covered volatile hydrocarbons in the range of C-C and oxygenated hydrocarbons such as alcohols, ketones and esters. Samples were collected using Carbotrap and Carbosieve SIII solid adsorption tubes and analysed off-line by thermal desorption and GC-FID analysis. Measurement results were used to create the input data for the source apportionment analysis with the Chemical Mass Balance Modelling technique. Emission profiles for traffic and solvent use were calculated.

The ozone problems (stratospheric, tropospheric and surface O) are an important part of atmospheric air pollution problems. One of the goals, outlined in the Recommendations of the meetings of the Ozone Research Managers (under World Meteorological Organization – WMO) was: the conducting of systematic measurements, which provide the basis for understanding the ozone regime and its trends.

The “heavy metal in the environment” collocation refers to any metallic chemical element and some metalloids (e.g. arsenic) that are toxic or poisonous for living organisms even at low concentration, e.g. Pb, Cd, Hg, As, Tl, Cr. They originate in the Earth’s crust as well as in the majority of wastes resulting from anthropogenic activities. Toxic effects of other heavy metals (Cr, Mo, Ni, As, Se etc.) have to be considered separately from the effects of biologic doses in which they exert their vital role.