Source apportionment of atmospheric urban aerosol based on weekdays/weekend variability: evaluation of road re-suspended dust contribution

During 1 year, twice per week (one working day and one sunday), 24-h averaged, separated fine and coarse atmospheric aerosol were measured, for total mass and chemical composition, in a suburban site on the outskirts of Lisbon. The relative concentration variability between working days and sundays allowed a better insight into the sources of atmospheric particulate matter. Receptor modelling based on Principal Component Analysis and Multilinear Regression applied to sunday and working day samples revealed marked differences during weekdays, in autumn/winter period. Based on the characteristics of the Principal Components it was possible to conclude that during autumn/winter, a predominant fraction of coarse and fine soil dust provides from anthropogenic activities, being presumably associated with road dust re-suspension by road traffic.