The present study was carried out on commercial types of Aswan granite used as building and decorative materials. Nearly 29 granitic rocks samples from 11 classes (black Aswan, red Aswan, dark Rosa, light Rosa, yellow Verdi, grey Shirka, Gandolla, Forsan, red Nefertiti, Royal, and white Halayeb) were collected from three stations near Aswan city for petrographical description and assessment of natural radioactivity. The petrographical study of granites was conducted by polarized-light microscope in order to determine their mineralogical composition and investigate their texture; the activity of the natural radionuclides 238U, Ra226, 232Th, and 40K was measured by gamma-ray spectrometry with a NaI(Tl) detector. The average values of the activities, 52.2 Bq kg−1, 57.8 Bq kg−1, 31.2 Bq kg−1, and 1055.7 Bq kg−1 of U-238, Th-232, Ra-226, and K-40, respectively, were higher than that the world average values of 35 Bq kg−1, 30 Bq kg−1 and 400 Bq kg−1 for 226Ra, 232Th, and 40K, respectively, according to the recommended levels from UNSCEAR reports. The minimum and maximum values obtained were compared with the value ranges from other locations in the Eastern Desert, highlighting the fact that that the maximum values obtained in this work are higher than those in other areas. According to the radiological hazards indices results, most samples lie in the permissible level ranges, suggesting their favorability for use as building materials. In contrast to that, some samples have some environmental parameters higher than the international levels, indicating their unsuitability as building materials.

The widespread usage of granite in the building sector motivated us to conduct this research and examine the material’s sustainability in terms of the investigated characteristics. The purpose of this paper is to discuss the statistical analysis results for the mineralogical impact on radiological hazards indices, such as the equivalent of radium, absorbed gamma dose rate, annual effective dose, internal and external hazard indices, as well as the gamma-ray index, that were calculated to estimate the environmental risks associated with these granites used as building materials, to protect the public from excessive radioactivity exposure. We focused primarily on statistical significance at a 95% confidence level. We employed a non-parametric test (Kruskal–Wallis Test) rather than a one-way ANOVA, to determine the statistical significance of the samples due to the lack of homogeneity or normality among them. To assess the difference between the samples, we used the Mann–Whitney Test on each pair of samples. Additionally, Pearson correlation coefficients for all the mineralogical results are computed. The presence of K-rich minerals (Kefeldspars, biotite) and accessories such as uranophane, uranothorite, allanite, xenotime, fergusonite, aeschynite, zircon, cassiterite, apatite, and sphene, which are mostly found in granitic rocks, determines the level of natural radioactivity of the investigated granites. Most of the rock samples analyzed have indicators of radioactive dangers that are within the acceptable level range, indicating that they are suitable for use as building materials. On the other hand, some samples have environmental criteria that are higher than international standards, indicating that they are unsuitable for use as construction materials.

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G. Gattar is located in the northern part of the Eastern Desert of Egypt, bounded by latitudes 26° 52´ - 27° 08´ N and longitudes 33° 13´ – 33° 26´ E and covers an area of about 178 km2. Eighteen samples, nine from uraniferous and nine from mineralized granites were measured radiometrically for 238U, 232Th, 226RaeU and 40K determination by Na-I detector and the radioactive minerals identified by alpha track method. Based on the petrography, radioactive mineral content and radioactivity, Gattarian granites were classified into uraniferous and mineralized granites. Uranium contents reach up to 229 ppm in the uraniferous granites and to 20300 ppm in the mineralized granites, which is extremely higher than the international limits. eTh/eU ratio of the studied uraniferous and mineralized granites show average ratios of 0.05 and 0.0044, respectively, which is extremely lower than the average of igneous rocks, suggesting uranium enrichment in reducing conditions. The uraniferous and mineralized granites U/Th ratios average are 62.23 and 4234.45, respectively, indicating that the studied two granitic types are considered highly productive rocks. The radioelements interrelations manifest that the distribution of radioelements not only magmatic but also related to hydrothermal redistribution of radionuclides associating with uranium deposition. The radiological hazard parameters, such as the dose rate (D), the annual effective dose equivalent (AEDE), radium equivalent activity (Raeq), external (Hex), internal (Hin) hazard indices and gamma index (Iγ) were estimated for these granites and compared with the international levels. Nearly, all the studied samples are to a great extent higher than the recommended permissible levels for all environmental parameters.