ANALYSIS OF HEAVY METALS IN ATMOSPHERIC PARTICULATES IN RELATION TO THEIR BIOACCUMULATION IN EXPLANTED PSEUDEVERNIA FURFURACEA THALLI ANTONELLA BARI 1 , ALESSANDRA ROSSO 1 , MARIA RITA MINCIARDI 1 , FRANCESCO TROIANI 1 and ROSANNA PIERVITTORI 2∗ 1 ENEA Centro Ricerche, Saluggia (Vercelli), Italy; 2 Dipartimento di Biologia Vegetale, Torino, Italy ( ∗ author for correspondence, e-mail: piervitt@bioveg.unito.it) (Received 25 January 1999; accepted 14 March 2000) Abstract. 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 (Piedmont, N. Italy). Thalli of the fruticose lichen Pseudevernia furfuracea were collected from an uncontaminated area and exposed for one year using two different techniques. Particulates were collected using a continuously operating partic- ulate sampler set up near the lichens explanted throughout the experiment survey. The results confirm both the importance of assessing contamination in rural areas corroborated by the analysis of the presence of the heavy metals in particulates in relation to the main wind directions and the validity of this lichen as biomonitor of airborne metal pollution, although meaningful differences were pointed out between the two different techniques of exposure. The significant correlation between most of the metals accumulated by lichens and the metal air concentrations shows a good evidence of their ability to represent atmospheric contamination. Keywords: atmospheric particulates, bioaccumulation, heavy metals, lichens, northern Italy, Pseude- vernia furfuracea, transplantation technique 1. Introduction Lichens were among the first organisms to be used as bioindicators (Grindon, 1859; Nylander, 1866; Gilbert, 1865; Skye, 1968) for assessment of changes in the environment caused by chemical pollution (Garty, 1993). Many studies have demonstrated their ability to absorb and accumulate persistent contaminants. They are therefore commonly employed to monitor radionuclides, metals, nonmetals (such as S and F) and other compounds present in the atmosphere (Goldsmith, 1991). Lichens are used as biomonitors both close to individual pollution sources and for monitoring large areas, either through examination of the spontaneous lichen flora (Nieboer et al., 1972; Garty et al., 1977; Nimis et al., 1983; Gasparo and Zappa, 1984; Bargagli et al., 1985, 1987; Olmez et al., 1985; Gasparo et al., 1989; Herzig et al., 1989; Sloof, 1995; Guidetti and Stefanetti, 1996), or by explantation from uncontaminated areas to places devoid of spontaneous colonisa- tion (Brodo, 1961; Garty and Fuchs, 1982; Caniglia and Zorer, 1992; Cardarelli Environmental Monitoring and Assessment 69: 205–220, 2001. © 2001 Kluwer Academic Publishers. Printed in the Netherlands.