Scientific African (Jul 2023)
Baseline assessment of naturally occurring radionuclides in borehole water of Asikam-gold mining community in Ghana
Abstract
The main source of drinking water and domestic usage for the population of Asikam in the Fanteakwa South Municipality is from hand-dug wells and mechanized boreholes. This study assessed naturally occurring radionuclides Radium-226(Ra-226), Thorium-232(Th-232) and Patassium-40(K-40) in the water from these sources. A random sample of 20 sampling points made up of 7 manually dug wells and 13 mechanically drilled boreholes were taken from Asikam Communities. The radioactive contents of the selected water sources were characterized and analysed using gamma spectrometry system with High Pure Germanium Detector. This assessment was carried out to determine the level of natural radioactivity that the processing of gold ore at the Asikam illegal mining site in Ghana exposes the public to. The mean activity concentrations of Ra-226, Th-232, and K-40 were obtained as 0.30 Bq/L, 0.49 Bq/L, and 2.44 Bq/L in the water samples respectively. The results from this study were found to be lower than the Guidance levels recommended by the World Health Organization (WHO, 2011; IAEA,2014) of 1 Bq/l for Ra-226 and Th-232. The estimated average committed annual effective dose for water samples was 0.17 mSv/yr which is lower than the 1 mSv/yr recommended limits for public exposure by the WHO. The cancer fatality risk and hereditary consequences from exposure to naturally occurring radionuclides which may result from the Asikam community's mining and mineral processing operations were evaluated and found to be insignificant. The findings of this study demonstrate radioactivity levels are within the range of natural background radiation levels as reported in the literature, and they compare favorably with findings from comparable studies conducted nationally and internationally. This study provides important baseline information for future research in the study area.
