PAH levels and profiles in the suspended particulate matter in Zagreb through four seasons.

This paper presents the analysis of polycyclic aromatic hydrocarbons (PAHs) measured in all four seasons in suspended particulate matter (SPM) collected with a high-volume sampler on one measuring site in the northern part of Zagreb. About 30 samples of SPM were analysed for each season, including workdays and weekends and there were no differences amongst them. The concentrations of all PAHs were highest in winter and lowest in summer. The spring PAH concentrations were lower than the autumn ones, as the spring had more sunny and warm days. The profiles of PAH/BaP at the measurement sites showed that the main source of PAHs in spring and summer was traffic while a substantial amount of autumn and winter PAHs, besides traffic, came from heating.