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In the present paper, the health risks to astronauts due to space radiation exposure and the excess cancer risk (ECR) caused by high-level natural radiation exposure area residents were estimated manes on the National Aeronautics and Space Administration (NASA) Space Cancer Risk (NSCR)-2012 model and RESRAD code, respectively. The total risk of exposure-induced cancer (REIC) and total risk of exposure-induced death (REID) were calculated for different ages and genders. In contrast, the mortality and morbidity due to High Natural Background Radiation Exposure areas (HNBRAs) were simulated for different genders and ages. The results showed that the morbidity of the HNBRAs area for males and females was less than the REIC value of the 6-month mission at the International Space Station (ISS). Also, the results indicated that the mortality of the HNBRAs area was equal to the REIC 6-month mission for males. The mortality rate in the HNBRA area was higher than the average rate for females in the REIC 6-month mission. Graphical abstract

Erbium (III)- and terbium (III)-containing (1, 3 and 5 wt%) silicate-based bioactive glass powders were synthesized using sol–gel method. Their structural and physical properties were investigated. Radiation attenuation properties of the prepared glass samples were examined using Monte Carlo simulations. The photon transmission properties of the prepared bioactive specimens were obtained via Phy-X PSD program and FLUKA simulation. Results showed that all of the glasses synthesized in the study were amorphous. The true density values were measured in the range of 2.57–2.68 g/cm 3 . Simulation studies revealed that the lowest neutron cross section was observed for the pure 13–93 bioactive glass sample and the maximum neutron cross section was noted for the prepared bioactive specimens of 5% Er and 5% Tb. Bioactive glass powders synthesized in the study have potential to be used as radiation shielding material in tissue engineering applications.

Nanoferrites of Ni 0.1 Cu 0.2 Mg x Zn (0.7− x ) Fe 2 O 4 ( x  = 0.0, 0.15, 0.25, 0.35, 0.45, 0.55 and 0.70 wt%) system fabricated using flash auto combustion technique. All investigated samples annealed for 2 h at 600 °C. XRD, FTIR and TEM were utilized to evaluate the structural characterization of as-prepared samples. The electrical DC resistivity of the investigated samples is evaluated as a function of frequency and temperature. The initial magnetic permeability ( μ i ) is dependent on the temperature and was measured at constant frequency 1 kHz and 10 kHz of the sinusoidal wave. A single-phase of spinel structure was formed and with increasing Mg content the peak (311) of 100% intensity decreases, which demonstrates the presence of Mg, which slows down the growth of the crystal as X-ray result. The FTIR spectra of the prepared ferrite samples are distinguished by the presence of two strong absorption bands ( ν 1  = 554 cm −1 ) and ( ν 2  = 449 cm −1 ). The morphological observation is determined by the transmission electron microscopy (TEM) and shows that the particles size ranged between 26 and 39 nm. It can notice shifted Curie temperature ( T c ) to a higher temperature by increasing Mg content. Mass attenuation coefficient ( μ m ), mean free path ( λ ), half value layer ( X 1/2 ), tenth value layer ( X 1/10 ) and effective atomic numbers ( Z eff ) for the studied samples, have been simulated using FLUKA (2020.0beta.2), while energy change from 15 × 10 –3 to 15 3+  keV with increasing Mg concentration, both μm and Zeff decrease. The largest value of μm and Zeff when x  = 0% while sample x  = 0.35% has a minimum value of λ , X 1/10 and X 1/2 .

Composition of (50 − x ) B 2 O 3 –30PbO–20ZnO– x La 2 O 3 ( x  = 0, 1.5, 3, 4.5, and 6) wt% glass system were synthesized using quench melt technique and simulated for their nuclear radiation shielding properties. Moreover, UV–visible absorption spectrum among 190–1100 nm and the glass optical parameters were measured. The optical energy gap ( E g ), the single-oscillator energy ( E o ), the dispersion energy parameter ( E d ), refractive index ( n ), and refractive dispersion index (no) were estimated. The obtained results indicated that ( E g ) was decreased with increasing La 2 O 3 content, but the refractive index ( n ) was increased. The addition of La 2 O 3 to glass network could provide preferable shielding features. The chosen amount of La and another metal oxide has been added to the glass. Shielding parameters such as half-value layer (HVL), mean free path (MFP), mass attenuation coefficient (MAC), and exposure rate in the photon energy range 15–300 keV have been simulated by MicroShield software. These results illustrate that the La5 glass sample has the best radiation shielding properties, among other investigated glasses. This type of glass sample can utilize for the construction of the monitoring screening windows in radiation areas, plats, or screening windows in X-ray diagnostic and for the walls of CT-scanner rooms.

The purpose of this research was to investigate the shielding characteristics of high-amount heavy metal oxide and Eu3+-activated borate glasses based on 10La2O3–50HMO–(40–x) B2O3–xEu2O3 (x = 0, 0.5, 1, 2, and HMO = PbO, Bi2O3). Critical gamma radiation attenuation characteristics, particularly mass attenuation coefficients of investigated heavy metal oxide glass samples, were determined using Monte Carlo simulations and the Phy-x/PSD software. Following that, we looked at the half-value layer, mean free path, effective atomic number, and build-up factors across a broad energy range (0.015–15 MeV). According to the study’s results, the addition of Eu2O3 enhanced the mass attenuation coefficient and effective atomic number, while reducing the half-value layer, mean free path, and accumulation factors. In terms of gamma radiation attenuation, the LBi50BEu glass system surpassed the LPb50BEu glass system in terms of overall shielding properties against nuclear radiation. Additionally, the heavy metal oxide glass’ efficacy as a neutron shield was determined using fast neutron removal cross-sections (ΣR). LBi50BEu2 glass was shown to be more effective in preventing the penetration of charged particle radiation.

High-level natural radioactivity, geochemical, geological, and radiological hazard assessment of the poorly investigated Wadi Gebeiy Dokhan volcanics rocks are discussed. Wadi Gebeiy Dokhan volcanics are located in Southwestern Sinai, Egypt, covering an area of ~1.3 km2. Dokhan volcanics rocks are represented by porphyritic dacite. Geochemically, they have medium-k characters and originate from calc-alkaline magma within a volcanics arc environment. Along the fault plane striking NNE-SSW, and at its intersection with the NW-SE fault plane, altered Dokhan volcanics occur with high radioactive anomalies. Radiological parameters (absorbed dose rate, radium equivalent, activity annual effective dose, external and internal hazard indices) are used to evaluate their suitability as an ornamental stone. Except for the absorbed dose rate, all the radiological hazard indices show that unaltered Dokhan volcanics can be used as an ornamental stone. Controversially, the applied radiological indices reveal that altered Dokhan volcanics have a higher content than the recommended values of UNSCEAR, reflecting their risk on human organs.

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.

This article investigates the impact of PtO 2 on the elastic, physical, and radiation protective properties of B 2 O 3 -based glasses in the composition of 25ZnO-25BaO-(50-x)B 2 O 3 -xPtO 2 , where x ranges from 0.0 (Pt0.0) to 1.0 (Pt1.0) mol%. The density (ρ) increased from 3.05 to 4.10 g.cm-3 but the oxygen-molar volume (OMV) decreased from 15.40 to 12.40 cm3/mol as the mol% of [Pt 4+ ] increased. The elastic moduli exhibited a positive correlation with the concentration of PtO 2 in the glass network. The linear-absorption coefficient (LAC) values in the energy spectrum being studied were arranged in the following sequence: (LAC)Pt0.0 < (LAC)Pt0.1 < (LAC)Pt0.2 < (LAC)Pt0.3 < (LAC)Pt0.5 < (LAC)Pt0.75 < (LAC)Pt1.0. Furthermore, there was an increase in the mass-absorption (MAC) coefficient. As the quantity of PtO 2 grew, the studied glasses exhibited a drop in their half-value (HVL) layer. By comparing the HVL values of the current samples with standard glasses, it was determined that the PtO 2 -based samples possess a photon protection capacity similar to that of RS-360 and RS-520 glasses. The effective removal cross section (ΣR) of Pt-x glasses was determined and observed to exhibit a similar pattern as the oxygen packing density (OPD).

For the Nb 2 O 5 -Li 2 O-Bi 2 O 3 -B 2 O 3 glass system, optical, structure, mechanical gamma, and neutron radiation shielding aspects were examined comprehensively. The two probabilities of the bandgaps, direct and indirect transition, were evaluated. The absorbance of the recent glasses was increased as Nb 2 O 5 increased. Moreover, the peak shifted to a longer wavelength as Nb 2 O 5 increased. Our results show a decreasing behavior of both kinds of the bandgap. Adopting XCOM within 0.04–15 MeV, LAC and MAC were evaluated for all samples and calculated MAC values are in excellent compliance with deduced FLUKA code respective MAC outcomes. Z eff , HVL, and MFP values were estimated. MAC, Z eff , HVL, and MFP values depended on glass components and energy. Moreover, using equivalent atomic numbers ( Z eq ) and the geometric progression fitting procedure, EABF values were calculated up to 40 mfp, within 0.015–15 MeV. Comparatively higher density (4.9454 g/cm 3 ), greater LAC, MAC, Z eff , Z eq , and lower HVL, MFP, EABF values achieved for 10Nb 2 O 5 -10Li 2 O-30Bi 2 O 3 -50B 2 O 3 glass indicated it as a better gamma shield. Furthermore, the calculated Σ R shows that the 10Nb 2 O 5 -10Li 2 O-30Bi 2 O 3 -50B 2 O 3 sample has commensurately greater Σ R (= 0.1744 cm −1 ).

The utilization of phosphorite deposits as an industrial resource is of paramount importance, and its sustainability largely depends on ensuring safe and responsible practices. This study aims to evaluate the suitability of phosphorite deposits for industrial applications such as the production of phosphoric acid and phosphatic fertilizers. To achieve this goal, the study meticulously examines the geochemical characteristics of the deposits, investigates the distribution of natural Radioactivity within them, and assesses the potential radiological risk associated with their use. The phosphorites are massive and collected from different beds within the Duwi Formation at the Hamadat mining area. They are grain-supported and composed of phosphatic pellets, bioclasts (bones), non-phosphatic minerals, and cement. Geochemically, phosphorites contain high concentrations of P 2 O 5 (23.59–28.36 wt.%) and CaO (40.85–44.35 wt.%), with low amounts of Al 2 O 3 (0.23–0.51 wt.%), TiO 2 (0.01–0.03 wt.%), Fe 2 O 3 (1.14–2.28 wt.%), Na 2 O (0.37–1.19 wt.%), K 2 O (0.03–0.12 wt.%), and MnO (0.08–0.18 wt.%), suggesting the low contribution of the detrital material during their deposition. Moreover, they belong to contain enhanced U concentration (55–128 ppm). They are also enriched with Sr, Ba, Cr, V, and Zn and depleted in Th, Zr, and Rb, which strongly supports the low detrital input during the formation of the Hamadat phosphorites. The high Radioactivity of the studied phosphorites is probably due to the widespread occurrence of phosphatic components (e.g., apatite) that accommodate U in high concentrations. Gamma spectrometry based on NaI (Tl) crystal 3×3 has been used to measure occurring radionuclides in the phosphorite samples. The results indicate that the radioactive concentrations’ average values of 226 Ra, 232 Th, and 40 K are 184.18±9.19, 125.82±6.29, and 63.82±3.19 Bq Kg -1 , respectively. Additionally, evaluations have been made of the radiological hazards. The calculated risk indicators exceeded the recommended national and world averages. The data obtained will serve as a reference for follow-up studies to evaluate the effectiveness of the Radioactivity of phosphatic materials collected from the Hamdat mine area.