Natural and artificial radionuclides distribution in some lichens, mosses, and trees in the vicinity of lignite power plants from West Macedonia, Greece

The distribution of natural K-40, Ra-226 and Ra-228 and artificial Cs-137 has been investigated in nonvascular mosses (9 species) and lichens (10 species) and vascular gymnosperm (1 species), angiosperm trees and shrubs (3 species) over the Kozani-Ptolemaida-Amynteon lignite basin in West Macedonia, Greece. Four lignite power plants producing about 70% of the electric energy of the country are to be found in this region. Both specific activity and transfer factors of these radionuclides have been determined by means of experiments. This study indicates that with regard to Ra-226 and Cs-137, nonvascular lichens and mosses have a much higher transfer factor (2.27 for Ra-226 and 43.77 Cs-137) compared with vascular plants (0.17 for Ra-226 and 0.03 Cs-137), but a lower one for natural K-40 (0.493 for lichens and mosses and respectively 1.190 for vascular plants).