High spatial resolution monitoring of benzene and toluene in the Urban Area of Taranto (Italy)

Atmospheric concentrations of benzene and toluene were assessed during three different seasons in the city of Taranto, using Radiello® diffusive samplers, in order to detect the most critical areas and to point out the sources contributing to pollution (vehicular traffic or industrial activities). High spatial resolution maps were built using a grid of 30 meshes drawn on the urban area of the city. For each mesh a monitoring site as representative as possible was chosen. Besides, in order to describe the highest levels of pollutants to which people is exposed, other 10 sampling sites were detected near high vehicular traffic crossroads or in particular critical zones of the city. The measurements of the concentration of these pollutants were carried out with Radiello® diffusive samplers for thermal desorption. The analysis of the results and the comparison between the map of vehicular traffic flows and the map of the concentrations of benzene suggested that in urban area the main benzene source is the traffic and the most significant pollution phenomena happens in zones characterized by narrow roads. Moreover it was possible to observe that high concentrations of benzene found in the NE zone of Taranto could be assigned to the industrial activities. This hypothesis was confirmed considering the diagnostic ratio between the toluene and benzene concentrations.