Trace elements determination in lichens and in the airborne particulate matter for the evaluation of the atmospheric pollution in a region of northern Italy

Lichens as biomonitors and neutron activation analysis as analytical techni que have been employed to study the distribution of trace elements (TE) in a mountain region of north Italy (Biella) characterized by settlements of w ool industry. Samples of airborne particulate matter collected onto filters , different species of lichens and samples of soils have been analyzed for the calculation of the enrichment factors (EFs) of more than 25 TE. By comp arison of the corresponding EFs, the most suitable lichen species (Parmelia caperata) was selected as specific TE biomonitor of the area investigated. Samples of this lichen were collected and analyzed for the evaluation of t he TE distribution in four different locations. The results obtained from t he analysis of the lichens gave information about the predominant direction of pollutants transportation, while those related to the concentrations fo und in the air particulate allowed the evaluation of the degree of the loca l TE atmospheric pollution. (C) 2001 Elsevier Science Ltd. All rights reser ved.