title: Natural radioactivity and dose assessment for phosphate rocks from Wadi El-Mashash and El-Mahamid Mines, Egypt.
abstract: The activity concentrations of (226)Ra, (232)Th and (40)K have been measured by gamma spectroscopy (sodium iodide NaI(Tl) detector) in phosphate rock samples, collected from the Wadi El-Mashash, a site located in the central eastern desert, and El-Mahamid in the Nile valley, Egypt. The average activity concentrations of (226)Ra, (232)Th and (40)K (Bq kg(-1)) in phosphate rocks were 665.8+/-33.4, 329.4+/-17 and 587.6+/-29.4 for Wadi El-Mashash and 566.8+/-28.6, 217.3+/-11.8 and 560.1+/-28 for El-Mahamid, respectively. The corresponding values for shale rocks were 85.2+/-5.7, 93.3+/-5.6 and 303.1+/-15.2 Bq kg(-1), respectively. As a measure of radiation hazard to the occupational workers and public, the Ra equivalent activities, representative level index and dose rates due to natural radionuclides at 1 m above the ground surface were estimated. The calculated external gamma-radiation dose received by the workers of the phosphate mine are 538 and 418 microSv/y, which is far below the permitted dose of 20 mSv/y recommended by the International Commission of Radiation Protection [ICRP-60, 1990. Radiation Protection: 1990 Recommendation of the International Commission on Radiological Protection, Oxford, Pergamon Preis.] for workers.
authors.affiliation: Physics Department, South Valley University, Faculty of science, Qena, Egypt.
authors.forename: Adel G E
authors.initials: AG
authors.lastname: Abbady
authors.forename: M A M
authors.initials: MA
authors.lastname: Uosif
authors.forename: A
authors.initials: A
authors.lastname: El-Taher
mesh_terms: D004534:Egypt; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D008906:Mining; D011197:Potassium Radioisotopes / Q000032:analysis*; D011874:Radiometry; D011883:Radium / Q000032:analysis*; D013051:Spectrometry, Gamma; D013910:Thorium / Q000032:analysis*
chemical_list: D011197:Potassium Radioisotopes; D013910:Thorium; D011883:Radium