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

Abstract

This study investigates groundwater uranium contamination and radiological risks in the 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 mining regions, providing insights into radiological health risks and geogenic contamination processes.