Abstract
The distribution of natural 40K, 226Ra and 228Ra and artificial 137Cs 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-Ptolemaïda-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 226Ra and 137Cs, nonvascular lichens and mosses have a much higher transfer factor (2.27 for 226Ra and 43.77 137Cs) compared with vascular plants (0.17 for 226Ra and 0.03 137Cs), but a lower one for natural 40K (0.493 for lichens and mosses and respectively 1.190 for vascular plants). Compared with unpolluted areas (0.25 Bq/kg), the 226Ra specific activity in lichens and mosses was systematically higher (26.43 and 56.74 Bq/kg respectively).