Determination of 210Po and 210Pb depositions in lichen and soil samples collected from Köprübaşı-Manisa, Turkey

Abstract

In this study, we aimed to determine the accumulations of 210Po and 210Pb in soil and lichen samples in Koprubasi. The Koprubasi district is home to the largest uranium deposits in Turkey. To date, there has been no study recorded in the literature related to 210Po and 210Pb depositions in lichens in Koprubasi. Six different lichen species (Cladonia convoluta, Parmelina tiliacea, Physcia stellaris, Pleurosticta acetabulum, Xanthoparmelia conspersa, and Xanthoria parietina) as well as soil samples were collected from seven sampling locations around Koprubasi. Lichens were used as biomonitors for 210Po and 210Pb deposition. The 210Po and 210Pb activity concentrations were measured in all the samples by alpha spectrometry. The activity concentrations in the lichen samples ranged from 64 to 577 Bq kg−1 with an average of 266 Bq kg−1 for 210Po and from 78 to 565 Bq kg−1 with an average of 333 Bq kg−1 for 210Pb. The activity ratios of 210Po/210Pb ranged from 0.80 to 1.99. In the lichen species, the mean 210Po activity values varied from 154 Bq kg−1 in Pleurosticta acetabulum to 390 Bq kg−1 in Xanthoparmelia conspersa. The range of the mean 210Pb activity was between 153 Bq kg−1 in Cladonia convoluta and 378 Bq kg−1 in Parmelina tiliacea. In the soil samples, 210Po and 210Pb activity concentrations were ranged from 14 to 1268 Bq kg−1 and from 19 to 1113 Bq kg−1, respectively. While the values of 210Po and 210Pb measured in the lichen samples are comparable with those of the literature, the results of 210Po and 210Pb in the soil taken from the uranium mine are higher than the results of the literature studies.