Appraisal of age-dependent geogenic radiation exposure and carcinogenic risks in the groundwater of Sevathur mine region, Pambar River basin, South India

Abstract

This study investigates groundwater uranium contamination and radiological risks in a part of Pambar River basin, South India, a region with significant geogenic radiation influenced by carbonatite rock formations. Uranium concentrations ranged from 5.8 to 240.8 μg L⁻¹ , with 35 % of samples exceeding the WHO limit of 30 μg L⁻¹ . Annual effective doses varied from 7.22 to 604.36 μSv y⁻¹ , posing higher risks to infants. Despite these findings, cancer mortality and morbidity risks remained below the permissible thresholds, with values of 6.29 × 10⁻⁵ and 9.15 × 10⁻⁵, respectively. A strong correlation between uranium and total dissolved solids (TDS) highlights the influence of geogenic and anthropogenic factors. Petrological and geochemical analyses revealed uranium-rich pyrochlore minerals in carbonatite rocks, with an average uranium concentration of 14.08 mg kg⁻¹ . This study emphasizes the need for proactive groundwater monitoring and management in uranium-affected regions, providing insights into radiological health risks and geogenic contamination processes.