Analysis of heavy metals in atmospheric particulates in relation to their bioaccumulation in explanted Pseudevernia furfuracea thalli

Lichens explants and airborne particulates were analysed for Cr, Zn, Cd, Pb , Ni, Fe, Mn and Cu content in a rural site in the province of Vercelli (Pi edmont, N. Italy). Thalli of the fruticose lichen Pseudevernia furfuracea w ere collected from an uncontaminated area and exposed for one year using tw o different techniques. Particulates were collected using a continuously op erating particulate sampler set up near the lichens explanted throughout th e experiment survey. The results confirm both the importance of assessing c ontamination in rural areas corroborated by the analysis of the presence of the heavy metals in particulates in relation to the main wind directions a nd the validity of this lichen as biomonitor of airborne metal pollution, a lthough meaningful differences were pointed out between the two different t echniques of exposure. The significant correlation between most of the meta ls accumulated by lichens and the metal air concentrations shows a good evi dence of their ability to represent atmospheric contamination.