Atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs) and total suspended particulates (TSPs) were measured in Istanbul during the cold season periods in a high-traffic area. Urban atmospheric PAH and TSP sample's were collected using Hi-h Volume PS-I samplers, and measured with HPLC-UV-visible and fluorescence detectors in series. Fifty-eight daily samples were collected from September 2006 to March 2007 at the Yildiz Technical University campus sampling site (European part of the city). Sixteen USEPA PAH and TSP concentrations were quantified as 138.24 +/- 63.60 ng m(-3) and 101.49 +/- 43.29 mu g m(-3). respectively. Results for a given air sample were presented as the sum of the vapor and particle associated fraction of the compounds. Maximum PAH and TSP concentration was observed during December 2006. It was found that lighter PAHs are the most abundant species in the analyzed samples. Total concentrations of these lighter PAHs were 110.11 +/- 52.65 ng m(-3). being 80% of the total PAHs averaged in this study, whereas that of the total heavier PAHs was 28.3 +/- 15.66 ng m(-3), and higher correlated with TSP value (correlation coefficient 0.47). In order to determine PAH sources. diagnostic ratios were performed for individual PAH concentrations. and the sampling site was found to be affected by traffic-related sources. with higher contribution from diesel than gasoline emission. Benzo(a)Pyren toxic equivalency factors (TEFs) to PAH concentration values were calculated indicating that the health risk of BaP and DiBenz(a,h)Anthracene (markers of traffic emissions) have the biggest portion in all the other species in the sampling site.