Health Hazards Assessment and Geochemistry of ElSibai-Abu ElTiyur Granites, Central Eastern Desert, Egypt

Abstract

In this paper, a thorough radio- and chem-ecological evaluation of ElSibai-Abu ElTiyur granites located within Egypt’s crystalline basement rocks was conducted for risk and dose assessments. Twenty granitic samples from the study area’s various lithological units were analyzed using high-resolution γ-ray spectrometry to determine the natural radioisotopes (U-238, Th-232, and K-40) concentrations. The average concentrations of U-238, Th-232, and K-40 were 38.72, 38.23, and 860.71 Bq/kg, respectively, exceeding the GAV (global average value) documented by UNSCEAR (Scientific Committee on the Effects of Atomic Radiation, Vienna, Austria). The radiological parameters and indices judging the usage of ElSibai-Abu ElTiyur granites in homes were computed. The obtained results showed that ElSibai-Abu ElTiyur granites are safe to be used by inhabitants as superficial building materials, as per the globally accepted values and the recommended safety limits approved by UNSEAR, WHO (World Health Organization, Geneva, Switzerland), ICRP (International Commission on Radiological Protection, Ottawa, ON, Canada), and EC (European Commission, Luxembourg). Further, the samples were subjected to ICP-MS (inductively coupled plasma mass spectrometry) analysis for quantifying radionuclide variations with chemical composition. Geochemically based on the ICP-MS results, the studied granites proved to be highly evolved A-type granites. They span the metaluminous to peralkaline fields. The REE patterns are characterized by the enrichment of the light rare earths (LREE) over the heavy ones (HREE) where (La/Yb)n = 5.2, (Gd/Yb)n = 1.63 with pronounced negative Eu-anomalies (Eu/Eu*)n = 0.49. The albite granite exhibits the highest concentrations of Ga, Nb, Ta, U, and Y, and REE (Gd, Dy, Ho, Yb) than the Na-metasomatic granites. Finally, the obtained data serve as a valuable future database for finding out the compatibility of the geochemical data with the natural radioactivity levels of granites.

Geochemical characteristics, hazards impact assessment and radiogenic heat production of the alkaline rocks

“…( 7a ), ( 7b ), and ( 7c ): where MLE and RF are the factors determining the mean life expectancy (66 years) 54 and the risk of fatal stochastic impact (0.05 Sv -1 for the overall population), respectively 55 . Considering the estimated ELCR (Table 4 ), all the values of ELCR in were found to be below the recommended threshold of 1.16 × 10 –3 (Sidique, et al 38 and Qureshi, et al 56 ) (Fig. 10 a).…”

“…As per Eq. ( 2 ) below, the activity concentration (AC) of the aforementioned radionuclides in every sample was calculated from the corresponding gamma lines of energy E while taking into account the mass of the sample (M s ), net peak count (N c,E ) at energy E, gamma decay transition probabilities I γ,E , and detector efficiencies (ε E ), as reported by Sidique, et al 38 and El-Gamal, et al 34 . …”

Natural Radioactivity Measurements and Radiological Hazards Evaluation for Some Egyptian Granites and Ceramic Tiles

“…On the other hand, Th-232 was identified via its daughters Ac-228 (968.9, 911.2, and 338.3 keV), Tl-208 (2614.5 and 583.2 keV), and Pb-212 (238.6 keV). The activity concentration (AC) and the uncertainty in activity concentration (U AC ) of the previously mentioned radionuclides in each sample were calculated from their corresponding gamma line intensities taking into account the sample mass, counting time, gamma decay transition probabilities, and detector efficiencies [41][42][43].…”

“…The activity concentration (AC) in the granites and ceramic tiles samples under investigation was estimated as follows [41]:…”

“…In fact, the Ra eq reflects the weighted total of the abovementioned three radioisotopes' concentrations within materials under the premise that gamma dose rates from 4810 Bq/kg of K-40, 259 Bq/kg of Th-232, and 370 Bq/kg of U-238 (Ra-226) are almost equal. From a radiation protection perspective, the ceramic and granite tiles studied herein are safe provided that their Ra eq levels are not above 370 Bq/kg [44] (permissible limit) corresponding to a yearly effective dosage of 1.5 mSv [41,45].…”