Abstract

Fifteen iron ore samples collected from Wadi Sawawin, Duba, Saudi Arabia were analysed using X-ray diffraction in order to determine mineral composition. Atomic absorption analysis was used to determine concentrations of Al, Ca, Fe, K, Mg, Bi, Pb, Th and U. Natural radioactivity concentrations were determined using gamma-ray spectrometry based on a hyper pure germanium (HPGe) detector; concentrations ranged from 1.89±0.39 to 4.50±0.53 Bq kg^-1, 1.21±0.16 to 3.60±0.56 Bq kg^-1 and detection level to 10.33±1.32 Bq kg^-1 for ²²⁶Ra, ²³²Th and ⁴⁰K, respectively. In order to assess the potential radiological risks to human health, the absorbed dose rate, radium equivalent activity, annual absorbed dose and external hazards were determined and compared to limits recommended by UNSCEAR. Results were within recommended safe ranges, meaning that the area under study is radiologically safe for habitation and that local iron ores are radiologically safe to be used as construction materials.

Key words: Atomic absorption spectrometer, natural radioactivity, radiological hazard, X-ray powder diffraction (XRD).