Assessment of heavy metals air pollution in urban and industrial environments using oak leaves as bioindicators

In recent investigation the leaves of Quercus cecciliflora are applied as bioindicator for evaluation of heavy metal air pollution (Cd, Pb, and Zn) in urban and industrial districts of Sofia and Sofia Field (Bulgaria). Except dry oak leaves, the rainwater was collected to survey the heavy metals deposition. The dependency between the mean heavy metal fallout and the metal concentration in oak leaves have been investigated. The results were compared with corresponding results from an incineration plant situated in the vicinity of Geneva, which were also collected for a similar study. A heavy metal fallout maps indicating the sites which are most exposed to pollution have been drawn.