RADIOMETRIC ASSESSMENT OF RADON-222 CONCENTRATION IN WATER SOURCES AROUND COAL MINING AREAS IN BENUE STATE, NIGERIA

Abstract

This research evaluated radon-222 levels in water sources around coal mining sites in Benue State, Nigeria. Nineteen water samples were collected and sent for analysis at the Centre for Energy Research and Training, Zaria, Nigeria. The result indicated an average concentration of 1428.416Bq/L, which significantly surpasses the World Health Organization’s guideline of 100Bq/L for safe drinking water. The elevated levels are likely due to the area's uranium-rich geological formations. Although the estimated annual effective doses from ingestion (0.001247mSv/y) and inhalation (0.010427mSv/y) are within the International Commission on Radiological Protection’s recommended limit of 1mSv/year for the general population, the lung-specific dose (7.535749mSv/y) and lung AEDE (62.85028mSv/y) indicate a notable risk, particularly from radon gas released during routine household activities. The excess lifetime cancer risk (3.6496 × 10⁻⁵), though relatively low, reflects a potential health concern over long-term exposure. In comparison to global findings, such as those from India and other parts of the world where radon levels are generally lower, the results of this study highlight a pressing need for intervention. Measures like water aeration or the use of granular activated carbon (GAC) filters are recommended to reduce radon content and safeguard public health.