Natural Radionuclide Concentrations by γ-Ray Spectrometry in Granitic Rocks of the Sol Hamed Area, Southeastern Desert of Egypt, and Their Radiological Implications

Abstract

The occurrence of heavy radioactive minerals in construction supplies such as granite has drawn attention to the extraction of heavy radioactive minerals. Granitic rocks were identified to serve an essential economic role in the study area’s surrounding locations. As a result, the current study attempted to detect the activity concentrations of 238U, 232Th, and 40K in the granitic rock samples tested and estimate the radiological dangers associated with these rocks. The obtained data on activity concentrations for 238U (610 ± 1730 Bq kg−1), 232Th (110 ± 69 Bq kg−1) and 40K (1157 ± 467 Bq kg−1) in the granitic samples (GR) were higher than the recommended worldwide average. The radioactive levels found in the samples were caused by radioactive materials being altered and trapped inside granite faults. The exposure to gamma radiation from the granitic rocks were assessed via various radiological parameters, such as radium equivalent content (856 Bq kg−1), absorbed dose rate (Dair) in the air (396 nGy/h), and annual effective dose for either outdoor (0.48 mSv y−1) or indoor (1.9 mSv y−1). Statistical analysis was performed to detect the correlations between radioactive concentrations and radiological parameters. The radioactive effects contributed by the uranium minerals were associated with the granitic rocks. Based on the analysis, the radioactive levels in the examined granitic surpassed the acceptable limits; therefore, they are not safe to use in building and infrastructure applications and may cause adverse health effects.