Evaluation of natural radioactivity levels and radiation hazards of some industrial Egyptian ores

The activity concentration of natural radionuclides (238U, 232Th, and 40K) in three industrial Egyptian ores including manganese ore (M), white sand (W), and dolomite ore (D) collected from Sinai area in Egypt were evaluated. The sample morphology was studied by EDS-XRD and SEM. Radiometric measurements were based on the characteristic spectral peaks of each radionuclide. The observed high activity of 238U confirmed that the natural radioactivity of the ores studied is mainly due to the uranium series. The calculated radium-equivalent activities (Ra-eq) were found to be 6553, 2848, and 431 Bq kg-1 for M, W, and D respectively. For M and W samples, the Ra-eq values are higher than the permissible level recommended in Egypt (1000 Bq kg-1). The annual effective doses were found to be 4.3 ± 0.3, 1.36 ± 0.02, and 0.66 ± 0.01 mSv year-1, respectively. The recorded data of the radioactivity background levels in the industrial samples studied can be used as reference values not only to assess the anthropogenic activities in the environment, but also to explain the metamorphic cycles of these radionuclides due to geological processes. © 2013 Pleiades Publishing, Ltd.