Radiometric Characterization of Coastal Sediments Using HPGe Gamma Spectroscopy: Distribution and Activity Levels of Key Radionuclides in Cox’s Bazar, Bangladesh

Abstract

Soil radioactivity studies are essential for environmental monitoring and radiation safety. In Bangladesh, particularly in coastal regions, little research has been conducted on the detection and quantification of radionuclides in soils. This study applied High-Purity Germanium (HPGe) gamma spectroscopy to measure natural and artificial radionuclides in selected soil samples from Cox’s Bazar, Bangladesh. Three representative samples were collected from different depths (surface,1ft,2ft), prepared, and analyzed following standard gamma spectrometric procedures.

The HPGe detector, enclosed in a 95 mm thick lead shield and cooled with liquid nitrogen, provided high resolution for accurate detection. Acquired
spectra were processed with Genie2000 software, and activity concentrations of Ra-226, Th-232, K-40, and Cs-137 were calculated. Results showed measurable concentrations of natural radionuclides within international baseline levels, with traces of Cs-137 detected, reflecting possible fallout contamination.

This work demonstrates the detection process, calculation methodology, and comparative analysis against UNSCEAR and IAEA standards. It also establishes a methodological framework for future baseline environmental monitoring in Bangladesh.