preliminary study of lead deposition on plant leaves in Tehran

Fifty-nine samples of washed and unwashed leaves of 4 species of plants in Tehran and 24 similar samples of the suburb [as control] were analyzed for Pb content. A significant difference was seen between Pb contents of washed and unwashed urban samples, while no significant difference was observed between the control samples. The mean Pb contents of the urban suburb samples were also significantly different. Washing removed 40% of lead from the surface of urban samples. Lead content was highest in fall and lowest at spring time. Results of this study showed that contamination of plant leaves with Pb aerosol in the city of Tehran is mainly a surface deposition and is due to the exhausts of the motor vehicles and low rainfall