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The present work is concerned with assessing the cancer risk contributed by the studied granite types including valuable metals, such as Cu, Au, and Ba mineralization, as well as radioactive-bearing mineralization, such as monazite and zircon, in south Monqul at Wadi Makhrag El Ebel, north Eastern Desert, Egypt. The mineralization analyses illustrated that copper mineralization containing chrysocolla and tenorite minerals were restricted to the alteration zone, especially (argillic, phyllic, and propylitic) in monzogranite. However, barite veinlets had an ENE–WSW trend, while gold mineralization was confined to quartz veins having NE–SW trends. Monazite and zircon are radioactive-bearing minerals recorded in monzogranite causing high radioactive zones in south Monqul. The radionuclide activity concentrations were detected in the studied monzogranites. The mean values of AU (103 ± 91 Bq kg−1), ATh (78 ± 19 Bq kg−1), and AK (1484 ± 334 Bq kg−1) in the monzogranite samples were higher than the recommended worldwide average. The change in radioactive-transporting minerals found inside granite faults caused the high amounts of radioactivity seen in the samples. Due to the monzogranites being applied in building materials, the radiological hazards were assessed by calculating risk indices such as annual effective dose (AED) and excess lifetime cancer risk (ELCR). The acceptable limit for the ELCR readings was surpassed. As a result, the investigated monzogranite samples are not suitable for use in infrastructure materials. [ABSTRACT FROM AUTHOR]

Different rock types (syenogranite, alkali feldspar granite and quartz syenite intruded by microgranite dikes and quartz veins) were investigated in the Nikeiba region in Egypt. The main components of the studied intrusive rocks, comprised of granites and quartz syenite, are plagioclase, amphibole, biotite, quartz and K-feldspar in different proportions. Ground gamma ray measurements show that syenogranite, quartz syenite and microgranite dikes have the highest radioactivity (K, eU, eTh and their ratios) in comparison with alkali feldspar granite. Geochemically, syenogranite, alkali feldspar granite and quartz syenite are enriched with large-ion lithophile elements (LILE; Ba, Rb, Sr) and high field-strength elements (HFSE; Y, Zr and Nb), but have decreased Ce, reflecting their alkaline affinity. These rocks reveal calc–alkaline affinity, metaluminous characteristics, A-type granites and post-collision geochemical signatures, which indicates emplacement in within-plate environments under an extensional regime. U and Th are increased in syenogranite and quartz syenite, whereas alkali feldspar granite shows a marked decrease in U and Th. The highest average values of AU (131 ± 49 Bq·kg−1), ATh (164 ± 35) and AK (1402 ± 239) in the syenogranite samples are higher than the recommended worldwide average. The radioactivity levels found in the samples are the result of the alteration of radioactive carrying minerals found inside granite faults. The public's radioactive risk from the radionuclides found in the investigated granitoid samples is estimated by calculating radiological risks. The excess lifetime cancer (ELCR) values exceed the permissible limit. Therefore, the granitoids are unsuitable for use as infrastructure materials. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The presence of heavy radioactive minerals in the studied granitoids from which the Wadi sediments leads to the study of the exposure to emitted gamma rays from the terrestrial radionuclides, such as 238U, 232Th, and 40K. The geological study revealed that the Wadi sediments derived from the surrounding granitoids, such as syenogranite, alkali feldspar granite, and quartz syenite. The mineral analysis confirmed that the granitoids were enriched with radioactive minerals, such as uranothorite as well as monazite, zircon, yttrocolumbite, and allanite. The mean activity of the 238U, 232Th, and 40K concentrations are 62.2 ± 20.8, 84.2 ± 23.3, and 949.4 ± 172.5 Bq kg−1, respectively, for the investigated Wadi sediments, exceeding the reported limit of 33, 45 and 412 Bq kg−1, respectively. Public exposure to emitted gamma radiation is detected by estimating many radiological hazard indices, such as the radium equivalent content (Raeq), external and internal hazard indices (Hex and Hin), annual effective dose (AED), annual gonadal dose equivalent (AGDE), and excess lifetime cancer (ELCR). The obtained results of the radiological hazards parameters showed that public exposure to emitted gamma radiation can induce various dangerous health effects. Thus, the application of the investigated sediments in different building materials and infrastructures fields is not safe. A multivariate statistical analysis (MSA) was applied to detect radionuclide correlations with the radiological hazard parameters estimated in the granite samples. [ABSTRACT FROM AUTHOR]

Argillic alteration and hematitization are the two extensive alterations that affected Um Safi rhyolite flow tuffs. Rare metal mineralization including radioactive minerals (thorite, uranothorite), Nb-bearing minerals (columbite, yettrocolumbite, Nb-rutile), zircon, REE-minerals (LREE-carbonate, xenotime) as well as molybdite, pyrite, fluorite, hematite and ilmenite have been identified by using Energy Dispersive Spectrometer (EDS) and are well recorded in argillic and hematitized samples. The investigated rhyolite flow tuffs show that the activity concentration of radionuclides changed from 1.2 to 453.2 Bq kg−1 for 238U, from 3.2 to 489.6 Bq kg−1 for 232Th, and from 31.3 to 88954.6 Bq kg−1 for 40K. The mean values of 238U, 232Th, and 40K activity concentrations are 90.8 ± 84.5, 122.9 ± 90.5 and 6286.7 ± 1562.2 Bq kg−1, respectively. The hazard factors are estimated. Their results exceeded the recommended limit. Thus, the investigated rhyolite flow tuffs are not safe to use in building materials and other construction industries. A multi-statistical approach is performed to show the correlation between the radioactive concentration and radiological hazard factors. This approach illustrates the positive correlation between uranium and thorium due to their contribution from the natural radioactive series—moreover, a strong correlation was obtained between potassium and all radiological parameters. Thus, the radioactive hazards impact in the present study is related to the presence of radioactive minerals such as thorite and uranothorite in addition to other accessory minerals. • Rhyolites and their tuffs represent an economic strategy to apply in various building materials. • The radioactivity is detected in the granitic rocks samples using GR-320 spectrometer. • The radioactive hazards parameters are computed, and the risk of the hazard is assessed. • The emitted radiation of Rhyolites and their tuffs at the studied area poses significant health risks. [ABSTRACT FROM AUTHOR]

Assessment of the radioactive impacts of building materials has become important before materials are employed in various infrastructure fields. The current study conducted a radiological survey on multiple granitoids in the Nikeiba area, southeastern Desert, Egypt. The petrographically studies were performed and illustrated the presence of radioactive bearing minerals in the investigated granitoids. The activity concentrations of 238U, 232Th, and 40K in these rocks, including the granitoids, are measured using a GS-256 spectrometer with a 0.35 L sodium iodide (NaI) thallium activated detector. The activity concentration of 238U, 232Th, and 40K varied from 1 ± 0.3, 4 ± 1 and 94 ± 15 Bq kg−1 to 274 ± 74, 229 ± 24, and 3537 ± 436 Bq kg−1 with the mean value of 83 ± 47, 104 ± 50 and 1140 ± 462 Bq kg−1, respectively. Multivariate statistical analysis is applied to detect the correlation and similarities of radionuclides with the radioactive hazard indices. Pearson correlation analysis depicts the distribution of 232Th controls the distribution of 238U in the granitoids. The primary radiological health hazard characteristics related to the concentrations of 238U and 232Th were determined by the variance of 89.76% derived using PCA. The cluster analysis dendrogram results indicate a good match with the correlation analysis. • Natural radioactivity characterization of granitoids in the studied area, Egypt, was performed. • Radiological hazard indices were computed, and the risk assessment was assessed. • The emitted radiation of granitoids at Neikeiba area poses significant health risks. [ABSTRACT FROM AUTHOR]

The present work aims to study gamma rays emitted by radionuclides such as 238U, 232Th and 40K from acidic Monqul volcanics. The studied volcanics are represented by a thick stratified lava flows interbanded with their pyroclastics. They are composed of thick lava flows of andesite and, to a lesser extent of basalt, and acidic volcanics including rhyolite and dacite. The average values of 238U, 232Th and 40K are (46 ± 24 Bq kg-1), (62 ± 11 Bq kg-1) and (1227 ± 318 Bq kg-1) in the rhyolite-dacite samples are greater than the worldwide average. The variation of radioactive bearing minerals observed inside granite faults produced the great amounts of radioactivity perceived in the samples. Calculating radiological risks is used to assess the public's radioactive risk from radionuclides revealed in the studied Rhyolite-dacite samples. The acceptable limit for excess lifetime cancer (ELCR) evaluations has been exceeded. As a result, Rhyolite-dacite are inappropriate for apply in building materials. • Rhyolite and dacite represent an economic strategy to apply in various building materials in Egypt. • A calibrated gamma-ray spectrometer is used to measure radioactivity in rhyolite and dacite samples. • The radioactive hazards parameters are calculated, and the hazard's risk is evaluated. • The rhyolite and dacite released radiation in the Monqul area poses a serious health concern. [ABSTRACT FROM AUTHOR]

The present study aims to assess Abu Rusheid and Um Naggat albite granite's natural radioactivity in the Central Eastern Desert, Egypt, using an HPGe laboratory spectrometer. A total of 17 albite granite samples were detected for this study. The activity concentrations were estimated for 238U (range from 204 to 1127 Bq/kg), 226Ra (range from 215 to 1300 Bq/kg), 232Th (from 130 to 1424 Bq/kg) and 40K (from 1108 to 2167 Bq/kg) for Abu Rusheid area. Furthermore 238U (range from 80 to 800 Bq/kg), 226Ra (range from 118 to 1017 Bq/kg), 232Th (from 58 to 674 Bq/kg) and 40K (from 567 to 2329 Bq/kg) for the Um Naggat area. The absorbed dose rates in the outdoor air were measured with average values of 740 nGy/h for Abu Rusheid albite granite and 429 nGy/h for Um Naggat albite granite. The activity concentration and gamma-ray exposure dose rates of the radioactive elements 238U, 226Ra, 232Th and 40K at Abu Rusheid and Um Naggat exceeded the worldwide average values that recommend the necessity of radiation protection regulation. Moreover, the corresponding outdoor annual effective dose (AEDout) was calculated to be 0.9 and 0.5 mSv y−1 for Abu Rusheid and Um Naggat albite granite, respectively, which are lower than the permissible level (1 mSv y−1). By contrast, the indoor annual effective dose (AEDin) exceeded the recommended limit (3.6 and 2.1 for Abu Rusheid and Um Naggat, respectively). Therefore, the two areas are slightly saving for development projects concerning the use of the studied rocks. The statistical analysis displays that the effects of the radiological hazard are associated with the uranium and thorium activity concentrations in Abu Rusheid and Um Naggat albite granites. [ABSTRACT FROM AUTHOR]

Stream sediment is a useful raw material used for building construction, mostly used in the desert parts of the world. Such sediment is a Naturally Occurring Radioactive Material (NORM), and, hence, it requires a radiological characterization to be used. This work aims to study the natural radioactivity in fifty points distributed in surface of stream sediments in the area of Gabal El Seila region, south-eastern desert of Egypt, since there is a lack of information about the radioactivity levels of the sediment samples from such recent growing interest area. The activity concentration of 238U, 232Th and 4 K natural radionuclides using a portable RS-230 γ-ray spectrometer were determined. Mean values are 38.51 ± 10.83, 33.35 ± 8.82, 659.18 ± 110.87 Bq/kg for 238U, 232Th, 4 K respectively. Radiological hazard indexes were computed and compared with the UNSCEAR and other worldwide ranges. All the results are statistically presented and discussed. They show that no significant radiation hazard coming from the studied area, with the most values lower than international recommended limits. The achievements of the present study fall within the measurements of natural environmental radiation in an unexplored area of great interest being a desert. The obtained results can be used as database for future research, and as tool for radiological awareness in the use of sediments as raw material. • Natural radioactivity characterization of Gabal El Seila region - Egypt, was carried out. • Radiological hazard indexes were computed to evaluate the human risk assessment. • 232Th/238U ratio showed 20% higher and 80% lower values than worldwide average value. • No significant natural radiation hazard comes from the region, lower than recommended levels. [ABSTRACT FROM AUTHOR]

One of the most well-liked energizing drinks is now tea, which is primarily used in Malaysia. The natural radioactivity in the associated soils where tea plants are cultivated plays a major role in determining the presence of radionuclides in tea leaves. The present study assesses the transfer of radionuclides from soil-to-tea leaves and then estimates the committed effective doses through tea consumption. Tea leaves and the associated soils were obtained from the largest tea plantation area, which is located in the Cameron Highlands, Malaysia. The marketed tea leaves in powdered form were obtained from the supermarkets in Kuala Lumpur. HPGe gamma-ray spectrometry was used to determine the prevailing concentrations of long-lived radioactive materials in tea leaves. Activity concentrations of 226Ra, 232Th, and 40K in tea soils ranged from 49 to 101.7 Bq kg−1, 74.5–124.1 Bq kg−1 and 79.6–423.2 Bq kg−1, respectively, while the respective values in tea leaves are 14.4–23.8 Bq kg−1, 12.9–29.5 Bq kg−1 and 297–387.5 Bq kg−1. Transfer factors of radionuclides showed typical values (<1.0) except for the 40K. The threshold tea consumption rates suggest that one should not consume more than 67 g of tea leaves per day (around 4 g of tea leaves are needed for making 1 cup of tea, so 17 cups per day) to avoid negative health effects. Committed effective doses due to tea consumption are found to be lower (5.18–6.08 μSv y−1) than the United Nations Scientific Committee on the Effects of Atomic Radiation (2000) reference dose guidance limit of 290 μSv y−1 for foodstuffs; however, it should be noted that the guidance limit is recommended for all foodstuffs collectively. Providing data on natural radioactivity in tea leaves grown in Malaysia, this study may help people manage a healthy lifestyle. • Radionuclides transfer from soil-to-tea leaves and associated doses are studied. • Tea leaves are collected from the largest tea estate in Malaysia. • Radioactivity in tea leaves are reported for the first time in Malaysia. • Committed effective dose found below the UNSCEAR guidance limit of 290 μSv y−1. • The reported data may be useful to maintain a healthy lifestyle. [ABSTRACT FROM AUTHOR]