Characterization of selected speciated organic compounds associated with particulate matter in ambient air of the outskirts of Rome

The organic fraction of airborne particulate matter includes a wide variety of organic compounds, but the present research focus is on Polycyclic Aromatic Hydrocarbons (PAHs) and their nitrated derivatives (nitro-PAHs) because of the well-known health risk associated with these organics. In order to identify and assess the sources of hydrocarbon inputs into the environment n-alkanes content and the relative carbon preference index were utilized. Special consideration was given to nitro-PAHs. The aim of this work was to demonstrate the presence in atmosphere of nitro-PAHs not usually studied, which may be responsible for part of the high direct-acting mutagenic activity of unknown origin observed for the airborne particulate material. Of the 38 particulate-associated nitro-PAH compounds measured, 21 were described for the first time and 17 were detected in real samples, although those 21 nitro-PAHs were reported as positional isomers of corresponding PAHs, with the position of the NO2 group not determined.