An Analysis for Distribution of Natural Radionuclides in Soil, Sand and Sediment of Potenga Sea Beach Area of Chittagong, Bangladesh

Abstract

A HPGe (High Purity Germanium) detector based, low background gamma-ray counting system was used for activity measurement in soil, sand and sediment samples collected from Potenga sea beach area of Chittagong, Bangladesh. The specific radioactivities of Radium ( 226 Ra), Thorium ( 232 Th) and Potassium ( 40 K) were measured in the above samples. The investigation reflects the lower deposition of minerals exist in the collected samples. From the measured specific radioactivities of the above three natural radionuclides, the radium equivalent activity (Ra eq ), the external hazard index ( H ex ), the external gamma absorbed dose rate and the annual effective dose were calculated. The obtained mean values of gamma absorbed dose rate in soil and sand samples and annual effective dose in soil, sand and sediment samples were found higher than the worldwide average as reported by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2000). The Ra eq values were in the range of 47.86 to 293.76 Bq · kg -1 and the H ex varied from 0.13 - 0.81, which indicated that the study area was radiologically safe for human being.