This study assesses naturally occurring radioactive materials and radon gas contamination in drinking water sources across the artisanal mining-dominated Wamba area, North-Central Nigeria, with the primary objective of evaluating radiological safety by accurately estimating radiation hazard indicators. Lithology-based analysis of radioelement concentrations (elemental and activity) alongside radiological parameters identified the key lithological contributors to radiation exposure. The recorded radiogenic hazards in the study area’s lithological units are highest in the migmatite, and the medium- to coarse-grained granites record the lowest. The estimated mean annual absorbed dose rate of 66. 33 \: nGyh^-1 slightly exceeds the average, while the average radium equivalent activity of 142. 69\: Bqkg^-1 and the indoor and outdoor annual effective dose equivalents, internal and external hazard indices, and gamma and alpha indices were all below the recommended safety thresholds. However, direct health risk indicators, the mean annual gonadal dose equivalent of 458. 59 µ \: Svy^-1 and mean excess lifetime cancer risk of 1. 139 \: \: 10^-3 surpass the standard safe limits. In drinking water sample evaluation, radon gas levels ranged from 0. 047 to 5. 64 \: BqL^-1, with an average of 1. 396 \: BqL^-1. The average annual effective dose (AEDE) from ingestion was 0. 010 \: mSvy^-1 for adults and 0. 020 \: mSvy^-1 for children, while AEDE from inhalation was 3. 51 \: mSvy^-1. Given the anomalous radiological parameter ranges exceeding the recommended thresholds in the study area, it can be inferred that the study area is not radiologically safe, despite no widespread cases of disease, such as cancer, having been reported. However, a further health evaluation study (spatial radiation epidemiology) is needed to assess the impact of the radiological hazard on the local population within the study area.
Adewumi et al. (Fri,) studied this question.