Spatial distribution modeling of radiometric analysis and radiation dose estimations in drinking water and soil samples from Siirt city in Türkiye

Abstract In this study, the spatial distribution model has been aimed to characterize the radiometric parameters in drinking water and soil samples of Siirt City in Türkiye using the geostatistical method. The gross α and β measurements in the water samples and radiometric measurements in the soil samples were performed using a gas proportional α/β counter (Berthold, LB 770 model) and a gamma spectroscopy system (HPGe-detector), respectively. The spatial distribution maps, covering the whole region using the ordinary kriging method, were created visually. The gross α and β activities in the water samples varied from 9 to 40 and from 21 to 252 mBq L−1. The corresponding arithmetic average of the annual effective dose of gross α and β of drinking water was estimated to be 5.3 and 52.3 μSv y−1, respectively. In soil samples, the arithmetic average values of 238U, 232Th, 40K, and 137Cs radionuclides were 17 ± 6, 20 ± 7, 445 ± 166, and 4 ± 6 Bq kg−1, respectively. The arithmetic average absorbed dose rate (D), annual effective dose (AED), and excess lifetime cancer risk (ELCR) values in soil samples were calculated as 38 nGy h−1, 0.05 mSv y−1, and 0.165 × 10−3, respectively, for soil samples. The radiometric parameters of the sample were lower than those of the guideline levels recommended in the literature. Furthermore, the interpolation maps were evaluated in terms of the soil structure of the region.