Assessment of Dose and Spatial Distribution of Natural Gamma Radiation in Nizamabad Municipality, Telangana, India

Abstract

Natural background gamma radiation constitutes a major component of environmental radiation exposure to the public. The present study aims to evaluate the absorbed dose rate, annual effective dose (AED), and spatial distribution of natural gamma radiation in Nizamabad Municipality, Telangana, India. Measurements were carried out at multiple locations using a portable survey meter at 1 m above ground level. The recorded dose rates were analyzed to estimate radiological hazard indices and mapped using GIS techniques to understand spatial variability. The measured gamma dose rates are expected to vary due to geological formations and soil composition, primarily influenced by radionuclides such as 238U, 232Th, and 40K. Similar studies in Telangana reported dose rates ranging from about 104–258 nGy h⁻¹ with an average AED of 0.24 mSv y⁻¹ , while other regions showed values up to 235 ± 47 nGy h⁻¹ . The results of the present study will help in assessing radiation exposure levels and identifying high background radiation zones, contributing to environmental safety and public health awareness.