The present work deals with radon pollution arising from granitic rocks using an Alpha Guard radon monitor. Forty-four granitic samples were collected from five sites located in the Central part of the Eastern Desert of Egypt. The minimum to maximum concentration of radon for the rocks of Gebel (mountain) El-Missikat MS, El-Gidamy GD, RieEl-Garra RG, El-Aradiya AR, and Kab-Amira KA were 49,597 ± 8773 to 236,029 ± 22,397 Bq m⁻³, 39,658 ± 8341 to 188,666 ± 20,545 Bq m⁻³, 39,854 ± 7645 to 91,393 ± 13,429 Bq m⁻³, 45,951 ± 9488 to 121,935 ± 14,869 Bq m⁻³, and 33,209 ± 6989 to 251,398 ± 25,759 Bq m⁻³, respectively. The surface and mass exhalation rates, the emanation coefficient, and annual effective dose (indoors) were calculated for all the studied samples. The average value of radon concentration in the collected samples was higher than the national reference level of 300 Bq m⁻³ recommended by ICRP corresponding to an annual effective dose of 4 mSv at work and 14 mSv at home. The measured values for the rock samples studied in the five sites surpassed the world average of soil in areas with normal levels of radioactivity. The MS granitic samples showed a potential radiological risk for human beings, therefore, it is important to carry out a detailed monitoring program for dose assessment.

This study provides an integrated geochemical, petrographic, and radiological assessment of the El Gara El Hamra and El Gara El Soda granitoids in Egypt’s Southwestern Desert. Whole-rock major, trace, and REE geochemistry, combined with tectonic discrimination diagrams, reveals that the granitoids belong to ferroan A-type suites and comprise both peraluminous and peralkaline varieties. These contrasting chemistries reflect heterogenous crustal sources and within-plate magmatic processes associated with late Neoproterozoic post-collisional extension. Elemental ratios (e.g., Nb/Yb, Ga/Al) and HFSE enrichments support an anhydrous, oxidized, high-temperature melt regime consistent with the regional evolution of the Arabian–Nubian Shield. High-resolution gamma spectrometry was used to quantify primordial radionuclides ( ²³⁸ U, ²³² Th, ⁴⁰ K). Thorium and potassium show pronounced enrichment in the peralkaline samples, whereas uranium displays moderate variability across the granitoid suites. Calculated radiological parameters—including absorbed dose rate (D _γ ), annual effective dose (E_annual), radium equivalent activity (Ra _eq ), and hazard indices—exceed global crustal averages but remain within ranges typical of A-type granites worldwide. Radiogenic heat production (RHP) varies significantly between the peraluminous and peralkaline groups, reaching up to 9.99 µW/m ³ , indicating favorable potential for shallow-crust geothermal exploration. Organ-specific dose modeling (ICRP-based) identifies the bone marrow and lungs as the most impacted tissues under hypothetical prolonged exposure scenarios. Although some samples exceed recommended limits for unrestricted building use, actual public exposure would depend on rock utilization and exposure geometry rather than intrinsic radionuclide concentrations alone. Overall, the El Gara granitoids represent a compositionally diverse A-type system with elevated heat-producing elements and moderate radiological significance. These findings highlight the need for site-specific radiological evaluation before large-scale quarrying or use as construction materials, and underscore their potential relevance for geothermal energy assessments.

This study describes a comparative assessment of the structural properties, mechanical properties and gamma-ray shielding effectiveness of monzogranite to determine whether or not they can be used for sustainable shielding construction materials. The results of the petrographic, X-ray fluorescence (XRF), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS) analyses reveal that the monzogranite is composed essentially of quartz, K-feldspar, plagioclase and biotite. The SiO₂ contents of all the monzogranite studied also indicated that they are highly crystalline (70.77% to 73.34% SiO₂ by weight) and chemically stable (therefore, monzogranite); other properties such as density (2.70 to 3.06 g/cm³), porosity (19 to 23%) and water absorption (12 to 15%) demonstrated the structural compactness and durability of the samples studied. Additionally, the mechanical properties of all of the samples were extremely high, and included: (a) the unconfined compressive strength ranged from 89.28 to 240.20 MPa; (b) the engineering modulus ranged from 40.6 to 66.5 GPa; (c) the Brazilian tensile strength ranged from 7.4 to 15.2 MPa; and (d) the flexural strength ranged from 9.3 to 16.4 MPa. The shielding effectiveness against gamma rays was rated over a wide range of photon energies (0.015–15 MeV) via Phy-X/PSD and experimentally using NaI (Tl) spectroscopy at specific gamma photon energies 0.662 MeV, 1.173 MeV and 1.332 MeV. The experimental measurements of gamma-ray attenuation were validated with Phy-X/PSD calculations, with the average variation being 5.8% and no single variation over 10%, and therefore, reliability has been successfully demonstrated. The linear attenuation coefficients (LACs) were measured from 24.674 cm⁻¹ at 0.015 MeV to 0.065 cm⁻¹ at 15 MeV, which illustrates the dependence of gamma-ray interactions’ mechanisms on the energy of the incoming radiation. The half value layer (HVL) went from 0.028 cm to 10.621 cm and the mean free path (MFP) increased from 0.041 cm to 15.323 cm. The best measured performance properties were attributed to specimen MB3, as it had the highest radiation protective efficiency (88.58% at 0.15 MeV) and the lowest radiation transmission (72.16% at 0.09 MeV) in comparison to all of the experimental conditions considered. The high attenuation properties of MB3 were attributed to its high density and high levels of iron oxide, Fe₂O₃. The present work demonstrates that monzogranite, specifically sample MB3, provides excellent mechanical strength, as well as effective shielding from gamma radiation. Therefore, monzogranite, and particularly MB3, is a creative alternative for sustainable construction, as it provides materials that will be used for radiation shielding in nuclear, medical and industrial applications.