Distribution of Pb, Cu, Ni and Zn in urban soils in Rome city (Italy): effect of vehicles

In this work the concentrations of Pb, Cu, Ni and Zn in soils of several public parks in Rome city (Italy) are studied in order to investigate if vehicle traffic could be one of the main sources of heavy metals in city soil. All the parks investigated are located near roads in which vehicle traffic is high. The results show that vehicle traffic contributes in a significant way to metal pollution in city soils. Consequently public parks can be considered areas at high risk, especially when they are located near important roads. Because soil pollution attributable to vehicle traffic is prevalently bound to a diffusion process, it is possible to reduce the heavy metal accumulation in soils of public parks with the presence of barriers such as walls and trees. It is also advisable to locate areas for children in the internal part of parks distant from roads.