Assessment of Gross Alpha Radioactivity and Derived ²²²Rn Activity Concentrations in Groundwater Sources in Mubi-North Metropolis, Adamawa State, Nigeria

Abstract

Groundwater abstracted from boreholes serves as the primary drinking water supply for many communities in Mubi-North Metropolis, Adamawa State, Nigeria, yet the radiological quality of these sources has received little systematic attention. This study quantified gross alpha radioactivity and derived radon (²²²Rn) activity concentrations in water samples drawn from five boreholes distributed across the metropolis. Samples were processed by evaporative concentration and the resulting residues were counted using a gas-flow proportional counting system (MPC 2000-DP) at the Centre for Energy Research and Training (CERT), Ahmadu Bello University, Zaria. Radon activity was subsequently calculated from gross alpha measurements in units of Becquerels per litre (Bq/L). Recorded radon values ranged from 0.0082 Bq/L at Site B (Adamawa State University) to 0.1518 Bq/L at Site D (Lokuwa Community Borehole). Every site returned a concentration well beneath the 0.5 Bq/L screening guideline prescribed by the World Health Organization and allied radiation protection authorities, confirming that the examined groundwater sources are radiologically acceptable for potable and domestic application under present conditions.