Biomonitoring of Environmental Pollution Using Dielectric Properties of Tree Leaves V. Saltas & D. Triantis & T. Manios & F. Vallianatos Received: 7 June 2006 / Accepted: 26 October 2006 / Published online: 14 December 2006 # Springer Science + Business Media B.V. 2006 Abstract In the present work, dielectric measure- ments were performed in plane-tree leaves collected from a polluted urban site and a natural unpolluted one, in order to investigate the sensitivity of dielectric relaxation spectroscopy to the detection of heavy metals pollution. Although heavy metal concentra- tions at the urban site are not found considerable higher than those at the natural site, the two samples exhibit different features in the recorded dielectric spectra. Evaluation of experimental data suggests that the dielectric modulus (M*(ω)) representation is the most suitable for accenting the different dielectric relaxation processes of each sample. The imaginary part of dielectric modulus M 00 (ω) was fitted using a three-term Havriliak–Negami relaxation function, with fitting parameters, which depend on the concen- trations of heavy metals. The lower frequency relaxation process is attributed to the ionic conduc- tivity of the samples, while the two others are due to different charge transport mechanisms of α-response. The investigation of plane-tree leaves in terms of their dielectric properties can be considered as a promising biomonitoring for environmental pollution. Keywords Biomonitoring . Dielectric spectroscopy . Heavy metals . Leaves . Pollution 1 Introduction In recent years, analysis of trace elements in tree leaves has been used as a potential biomonitoring method for identifying spreading of pollution from industrial, domestic and vehicle emissions (Alfani, Baldantoni, Maistro, Bartoli, & Virzo De Santo, 1997, 2000; Alfani, Bartoli, Rutigliano, Maistro, & Virzo De Santo, 1996; Alfani, Maistro, Iovieno, Rutigliano, & Bartoli, 1996; Maisto, Baldantoni, De Marco, Alfani, & Virzo De Santo, 2003; Swaileh, Hussein, & Abu-Elhaj, 2004). However, the above chemical analyses are expensive and time consuming processes and alternative methods such as magnetic surveys of tree leaves have been proposed to identify and delineate high polluted areas, in addition to the clas- sical air quality monitoring systems (Georgeaud, Environ Monit Assess (2007) 133:69–78 DOI 10.1007/s10661-006-9560-7 V. Saltas (*) : F. Vallianatos Department of Natural Resources and Environment, Technological Educational Institute of Crete, 3 Romanou St, Chalepa, 73 133 Chania, Crete, Greece e-mail: vsaltas@chania.teicrete.gr D. Triantis Materials Research Laboratory, Department of Electronics, Technological Educational Institute of Athens, Athens, Greece T. Manios School of Agricultural Technology, Technological Educational Institute of Crete, Chania, Crete, Greece