Distribution and Comparison of Natural and Anthropogenic Radionuclides in Sediment Below and at Surface level in Charfassion Island, Bhola, Bangladesh

Abstract

In order to assess the activity concentration of natural and anthropogenic radionuclides in the Charfassion Island, Bhola, Bangladesh, the lower level sediment samples were analyzed by using Broad Energy Germanium (BEGe) detector. Average activity concentrations of ²³⁸U, ²³²Th and ⁴⁰K were found 19.34±4.37 BqKg^-1, 31.14±5.58 BqKg^-1 and 767.96±27.71 BqKg^-1. These results were used to calculate the radiation hazard parameters like radium equivalent activities (Raeq), representative level index (Iγr) and compare mobility of natural radionuclides through the sediment. It has been found that ²³⁸U and ⁴⁰K has a little bit higher mobility than the ²³²Th. Due to natural radionuclides in sediment, the effective annual outdoor dose in the study area is 0.07 mSv; which is within the accepted range 0.07 mSv and representative level index (Igr) is also found to be 0.95 BqKg^-1. The findings from this research work would be useful to evaluate the population exposure from radionuclides in this island.