Assessment of Radiological Hazards of Natural Radionuclides 226Ra, 232Th, and 40K for Valley Sediments, Wadi Al-Maia, Eastern Desert, Egypt

This study investigates the natural radioactivity of 40K, 226Ra, and 232Th in valley sediments from Wadi Al-Maia located in Egypt’s Eastern Desert. Radiation monitoring was conducted using high-resolution gamma-ray spectrometry with a NaI(Tl) detector. The activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K were measured. Based on these measurements, several radiological hazard parameters were calculated, including the absorbed dose rate (ADR), radium equivalent activity (Raeq), gamma index (Iγ), annual gonadal dose equivalent (AGDE), annual effective dose equivalent (AEDEout and AEDEin), and the external and internal hazard indices (Hₑₓ and Hᵢn).The average values of these parameters were 347 nGy/h (ADR), 724 Bq/kg (Raeq), 2.73 (Iγ), 2471 μSv/year (AGDE), 425 μSv/year (AEDEout), 1700 μSv/year (AEDEin), 1.96 (Hex), and 2.47 (Hin), all of which exceed the worldwide recommended limits. These results indicate that the study area exhibits elevated natural radioactivity levels and potential radiological health risks. The findings can serve as a baseline for future monitoring of natural radionuclide contamination and radiological risk assessment in the Eastern Desert of Egypt.