Evaluation of natural radioactivity level in Delanta-Dawunt, Wollo District, Ethiopia
Mekuanint Lemlem Legasu, A. K. Chaubey
Abstract
In the Delanta-Dawunt district of Ethiopia’s northern eastern Amhara region, twenty-one different environmental samples (gemstones) were gathered. This is one of the opal-mining (gemstone) locations in Ethiopia. We divided the 21 obtained samples into seven groups. The study’s major goals were to quantify the activity concentration of gemstones (opals) and examine the health implications. For 226Ra, the activity concentration ranged from 11.97 ± 2.46 to 62.44 ± 14.99 Bq kg−1, 25.69 ± 3.69 to 137.84 ± 13.23 Bq kg−1 for 232Th, and 184.84 ± 3.59 to 968.56 ± 18.16 Bq kg−1 for 40K. 226Ra, 232Th, and 40K were found to have mean radioactivity concentrations of 29.84 ± 6.53, 68.44 ± 18.94, and 390.87 ± 6.09 Bq kg−1, respectively. Radium equivalent activity (Raeq), absorbed dose, annual effective dose equivalent, external and internal radiation hazard (Hex and Hin) index, and activity utilisation index have mean values of 151.68 19.46 Bq kg−1, 72.19 8.48 nGy h−1, 0.07 0.01mSv y−1, 0.43, 0.51, 0.57 0.08, and 0.29 0.03. 232Th has higher specific activity than the global average, while 40K has the same. Meanwhile, the absorbed dose is higher than the world’s means value. The average value of excess life cancer risk found in this study is the same as the world’s average value.