Monthly ambient air and surface soil samples were taken for analysis in the outskirts of Madrid in an open urban area from November 1998 to October 1999. Thirty-one polychlorinated biphenyl congeners were analysed, selection being done according to their abundance in environmental samples. The present work shows the results obtained when factor analysis (FA) and cluster analysis were applied to concentration data of seventy-one ambient air samples (polyurethane foam plugs and filters). Both chemical parameters (concentrations and total suspended particulate) and two meteorological parameters (temperature and wind velocity) were determined weekly during the sampling period. A bivariate correlation analysis was previously performed to estimate relationships between PCBs and, also between soil and filter medium.