Distribution of radionuclides in soil samples in and around Dhaka City

The concentrations of the natural radionuclides of the uranium and thorium series and of 40K and a fission product 137Cs have been determined by gamma-ray spectrometry in soil samples collected from Dhaka city and its neighbouring environs. Values of the radionuclides present in the samples were greatly influenced by the geomorphological conditions in the area. The results have been compared with other global radioactivity measurements and evaluations. The typical concentration of 137Cs found in near-surface samples ranged from 5 ± 1 to 10 ± 1 Bq kg−1, this being greater than for samples taken at greater depths, i.e. from 12.5−17.5 cm and 27.5−32.5 cm.