Monitoring of traffic-related pollution in a province of central Italy with transplanted lichen Pseudovernia furfuracea.

The ability of transplanted lichen Pseudevernia furfuracea to biomonitor specific airborne pollutants (heavy metals and polycyclic aromatic hydrocarbons­PAHs) was investigated at five stations with different traffic densities in Viterbo, Italy. Exposed lichen showed high levels of all analysed pollutants; greatest values were for Zn (147­252 µg/g dw), Pb (24.9­34.6 µg/g dw), fluoranthene (37­107 ng/g dw), pyrene (23­124 ng/g dw). Comparison between contaminants concentration in lichens before and after exposure showed "accumulation" or "severe accumulation" rates in more than 90% of each substance. Besides, Pseudevernia furfuracea accumulated airborne PAHs in a manner that was proportional to traffic density.