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Information on the elemental constituents of atmospheric aerosols is of basic importance in studying atmospheric processes for a detailed understanding of the physics and chemistry of the atmosphere. Environmental pollution and its impact can be tested in the same way, too.

In the present review we survey the main research fields in aerosol analytics that can be investigated with the application of the PIXE method. The nature of emission sources, emission inventories, aerosol transport and its tracing, arctic aerosols and climatic influences are mentioned along with methodological features of the present-day PIXE technique and its combined applications with other tools of instrumental analytics.

Proton Induced X-ray Emission (PIXE) analysis has been performed to determine the longitudinal distribution of coarse- and fine-fraction as well as total aerosol concentrations at ground level in the neighbourhood of a single emission source situated in a valley in complex terrain. Average environmental impact on the quality of air can be guessed by the comparison of the total .concentration data obtained in two sampling stations with those of a reference background sampling station. Transport properties in the terrain were derived by comparing the measured distributions to the one calculated from a simplified version of the Gaussian plume formula apt for modelling short distance transport over a plane area.

Samples of atmospheric aerosol particles collected at various height over a suburban sampling site were analyzed with respect to 13 elements by PIXE method. Concentrations, enrichment factors, and fine-to-coarse concentration ratios of the fractions were obtained by averaging over height distribution. In one of the sampling experiments dry-deposition velocities were deduced for seven elements from the height distribution.

Longitudinal distribution of ground level aerosol concentrations have been measured in the neighbourhood of an emission source of mixed character by the PIXE method. The source was located in a valley in hilly terrain. The elements observed are divided into two groups according to the magnitude of the fine-to-coarse concentration ratio. The elements of small ratios are crust-related elements and the concentration of these elements show strong decrease with transport distance. The elements of large ratios are oil-related elements and the concentration are relatively stable during short-range transport.

The study of atmospheric aerosols originating from natural and anthropogenic processes is of basic importance for a detailed understanding of the physics and chemistry of the atmosphere. Particle Induced X-ray Emission (PIXE) technique has been used by the authors for studying regularly the elemental composition of rural, suburban, and urban aerosols collected at six sampling sites in Hungary. Observed data presented in terms of concentrations and regional signature values and evaluated wind sector partition and in transport modelling revealed the natural/anthropogenic contribution to the moderate air pollution here. Dry deposition velocities have been deduced for elements V, Cr, Mn, Co, Ni, Cu, Zn, Cd, and Pb. Model calculations based on annual emission data and observed elemental concentrations resulted in total dry and wet deposition masses of the above elements to the territory of the country. At the same time, deduced budget data for the emission and deposition of the constituents indicated whether the country represents a net source or a sink for the above mentioned elements in the regional aerosol transport between neighbouring countries. Evidences have been found for intrusion events of Saharan aerosol to the atmosphere of Hungary. Part of the data collected recently will be evaluated in the frame-work of an international co-ordinated research programme.