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Yellow ochre is the basic material used in the manufacture of yellow oxide (a commercial product). Yellow ochre samples were taken from three different formations in southwestern Sinai: Abu Hamata, Um Bogma, and Abu Zarab. Yellow ochre occasionally exists in Abu Hamata Formation particularly in El Ferah area, associated with Fe–Mn ore in Wadi El Sahu (Um Bogma Formation) and in Himayer area (Abu Zarab Formation). The XRD analysis of the raw material reveals that they are mainly composed of goethite, which is associated with quartz and kaolinite in El Ferah area, hematite, kaolinite and quartz in Himayer area, and kaolinite, gypsum and quartz in Wadi El Sahu. The commercial product is mainly composed of goethite, quartz, and calcite. The heavy mineral investigation shows that some yellow ochre samples contain zircon and rare earth sulfate which may be responsible for the radioactivity of ochre due to their thorium and uranium content. The average values of specific radio-activities of most radionuclides in the samples of Himayer area I and II, and El Sahu I are higher than the respective world averages, while their activities are lower in El Ferah and El Sahu II. Th/U and Ra/U ratios exhibit vigorous changes in physico-chemical conditions during uranium leaching and deposition. Most of the radiological parameters in the ferruginous sediment and commercial product samples from El Ferah, El Sahu II, and Himayer II are lower than the recommended international values but higher than those from Himayer I and El Sahu I samples. The plotted hierarchical cluster analysis (HCA) exhibits that the main contributors for the hazards of these sediments and their commercial product are 238U, 232Th and 226Ra in Himayer I &II, commercial products, and El Ferah area, 232Th and 226Ra in El Sahu II , 232Th, 40K and 226Ra in El Sahu I. [ABSTRACT FROM AUTHOR]

The scale material in TENORM waste from petroleum industry was characterized using nuclear and non-nuclear techniques. The scale TENORM samples were collected from the Ras Shukeir area on the west bank of the Suez Gulf in Egypt during gas and oil production. These scales represent the TENORM deposits formed in the pipelines and removed during the periodical maintenance. X-ray fluorescence analysis showed that the main elements in all investigated fractions were Si, Fe, Mg, Ca, Sr, and Ba in addition to traces of some heavy elements, e.g. Pb, Cr, and Zn. The radioactivity concentrations of natural radionuclides 226Ra, 232Th, and 40K in seven particle size fractions were found to be in the range from 14.1 ± 0.4 to 28.9 ± 0.9, from 5.0 ± 0.2 to 9.5 ± 0.4, and from 0.25 ± 0.02 to 0.43 ± 0.02 kBq kg-1, respectively. The radiation hazard parameters were calculated. The values obtained are much greater than the accepted values. The results were compared to the values reported for other countries. [ABSTRACT FROM AUTHOR]

The present work aims to obtain adequate knowledge about the natural radioactivity levels and the related radiation hazard at the northwestern coastal zone of Egypt as part of the Egyptian regulations and nuclear law. Thirty-eight soil samples of different geologic formations were collected and analyzed using gamma spectrometer equipped with hyper-pure germanium (HPGe) detector. The mean activity concentrations of 238U, 226Ra, 232Th and 40K in all soil samples are 29.40, 25.18, 11.22 and 159.16 Bq kg−1, respectively. Those activity concentrations are below the soil world average. The activity concentrations of 238U are found to be higher than that of 226Ra and 232Th. The spatial patterns of the activity concentrations of these radionuclides were also presented using the geographical information system (GIS). Radiation hazard indices were assessed through the calculation of radium equivalent activity (Raeq) Bq kg−1, external and internal hazards (Hex, Hin), absorbed dose rate (ADR) nGy h−1 and annual effective dose (AED) mSv year−1. The average values of ADR and AED are 25.41 nGy h−1 and 20 μSv year−1, respectively. These values are below the soil world average of 59 nGy h−1 and the effective dose limit of the public radiation exposure of 1 mSv year−1. [ABSTRACT FROM AUTHOR]