In the present work, the specific activity concentrations of natural radionuclides of ²³⁸U and ²³²Th chain members, as well as ⁴⁰K were measured in phosphate samples using a gamma-ray spectrometric technique based on high-resolution hyper-pure germanium detectors (HPGe). Samples were collected from the El-Sebaiya area at the Aswan zone, Egypt. The external hazard index(Hex), the external absorbed dose rates(D), the annual effective doses (E) and the excess lifetime cancer risk (ELCR) due to gamma radiation from these samples have been calculated and compared with the corresponding average worldwide values. The evaluations of the associated radiological hazards from these materials on the workers during mining processes in the El-Sebaiya area were carried out.

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