CHARACTERIZATION OF THE AIR-POLLUTION IN THE URBAN AREA OF MADRID

An attempt is made to characterize for the first time the urban pollut ion of Madrid using the combination of conventional gas measurements a nd an ion beam analytical technique (PIXE) for aerosol monitoring. Dif ferent sets of samples were collected selecting different seasons of t he year; winter and summer 1992, and also different sampling times; 3 h and 24 h. A group of 18 elements in the mass range from Si to Pb cou ld be analyzed. Concentration of gases in the air was recorded for the following: CO, NOx) NO2, SO2 and CxHy. Four sources contributing to t he air pollution were obtained by means of absolute principal componen t analysis where automotive transport emerges as the dominating one. T he combination of aerosol (PIXE) and gas data as input to a receptor m odel proved to be fruitful for the understanding of the underlying che mical and physical processes governing the observed pollution levels. This is a preliminary study whose results will supply the trends and s trategies for a more thorough characterization.