Assessment of health risk associated with radon concentration in well water samples from Katagum, Bauchi, Nigeria

Abstract

Radon is a radioactive gas that can build up in groundwater, especially in geologically active areas. Long term exposure through drinking or inhaling radon contaminated water can increase cancer risk, making its monitoring vital for public health and safety. To evaluate the presence of radon (²²²Rn) in groundwater sources within a defined region of Katagum, Bauchi State, Nigeria, in order to identify areas that may require further environmental health monitoring and intervention. A Radon concentration in well water was analyzed using liquid scintillation counting (Model: Tri CarbLSA1000). Fifteen samples were collected across all administrative wards of the study area. The study also estimated the annual effective radiation dose for different age groups; adults, children, and infants, based on ingestion and inhalation exposure pathways. Measured ²²²Rn concentrations ranged from 26.26 to 45.98 Bq/L, with a mean value of 36.22 Bq/L. While these values are below the recommended limits set by WHO, USEPA, and UNSCEAR, the estimated annual effective doses for adults (0.09 mSv/yr), children (0.26 mSv/yr), and infants (0.40 mSv/yr) exceed the reference levels advised by WHO and UNSCEAR, indicating potential radiological health risks despite compliant water concentrations. Although radon concentration in water samples was within acceptable international limits, the associated annual effective doses, particularly for children and infants, surpassed recommended thresholds. This suggests a need for ongoing monitoring and targeted mitigation strategies, such as aeration of drinking water and public health education, to reduce long-term health risks in the affected communities.