Physicochemical and spatial distribution patterns of radon and its parent radionuclides in the uranium-mineralized Singhbhum Region, India

Abstract This study examined the distributions of radon and its parent radionuclides 226 Ra and 238 U in groundwater samples from the Singhbhum region, Jharkhand, India. Radon showed a heterogeneous spatial distribution pattern, with a lognormal distribution. A good correlation between radon bubbler-Lucas cells and liquid scintillation counting techniques was observed for radon monitoring. 222 Rn and 226 Ra were negatively correlated with pH, suggesting the mobilization of radionuclides at low pH. Uranium was positively correlated with common ions (e.g., Ca, Mg, and SO 4 2− ). The activity ratios among the radionuclides indicated disequilibrium, with 222 Rn origin controlled by parent radionuclide activity in bedrock. The 226 Ra and 238 U concentrations in groundwater were lower than the limits recommended by the WHO.