Assessment of the risk of urban exposure to polyaromatic hydrocarbons in cities of Transylvania, Romania

The goal of this study is to estimate the urban environmental risk of exposure to polyaromatic hydrocarbons (PAHs) in the atmosphere of six cities of Transylvania region using moss as biomonitor and GC-MS analysis. The carcinogenic potential of the measured atmospheric PAHs was estimated by the benzo[a]pyrene toxicity equivalent (BaPeq) and the toxic equivalence factor (TEF), respectively. The PAHs concentration found in the analysed dried moss ranged from 45.27 ng g(-1) in Targu Mures (S5) to 393.98 ng g(-1) in Cluj-Napoca (S6) with a median of 217.18 ng g(-1). Regarding the toxicity results of s(16BaPeq), these had the minimum value of 5.69 ng g(-1) in Bistri?a (S4), while the maximum value of 48.65 ng g(-1) was reached in Cluj-Napoca (S6). The median of the investigated urban areas was 19.75 ng g(-1) being comparable to other studies conducted worldwide. The contribution of the dibenz[a]anthracene (DahA) and benzo[a]pyrene (BaP) to the results of BaP equivalency is significant, the median exceeding 56.33%. Thus, for a better understanding of the possible effects of PAHs on human health, simply measuring the concentration of the 16 priority PAHs would not be sufficient.