State of the Practice Worldwide: Identification of Radiogenic Element Sources and Evaluation of Water Quality in Tuban Delta, Yemen

ABSTRACT

This study presents an accurate assessment of natural radioactivity levels of ²²⁶ Ra, ²³² Th, and ⁴⁰ K in 49 groundwater samples collected from the Tuban Delta in Yemen. Gamma ray spectroscopy was employed to quantify the radioactivity concentrations in the analyzed samples. In addition to radionuclide assessment, heavy metal concentrations were also measured. The results revealed average activity concentrations ranging from 0.83 to 6.5 Bq/L for ²²⁶ Ra, 1.2 to 3.7 Bq/L for ²³² Th, and 110 to 172.3 Bq/L for ⁴⁰ K. To evaluate potential health risks, effective doses were calculated based on measured radionuclide concentrations and typical water consumption patterns, yielding ranges of 0.3–1.29 mSv/year for infants, 0.04–2.20 mSv/year for children, and 0.02–1.34 mSv/year for adults. Pearson's correlation analysis revealed strong positive relationships among major ions (Ca ²⁺ , Mg ²⁺ , Na ⁺ ) and natural radionuclides ( ²²⁶ Ra, ²³² Th), indicating geogenic influences on groundwater chemistry. Principal Component Analysis identified two main components explaining 83.7% of the variability, highlighting mineral dissolution and geochemical processes as key factors controlling water quality and radionuclide distribution in the Tuban Delta.