Description
The current study is interested in investigating the radiological behavior and mineralogical controls of natural radioisotopes (²³⁸U, ²²⁶Ra, ²³²Th, and ⁴⁰K) in granitic pegmatites from the Abu Zawal Area (AZA), Eastern Desert, Egypt. The pegmatites, enriched with thorite, zircon, monazite, ferrocolumbite, and fergusonite, display abnormally high activity concentrations up to 1272 Bq/kg for ²³⁸U, 723 Bq/kg for ²³²Th, and 570 Bq/kg for ²²⁶Ra far exceeding international safety limits. Radiological assessments revealed elevated radium equivalent activity (Raeq ≤ 1984 Bq/kg), hazard indices (Hex ≤ 5.36), and excess lifetime cancer risk (ELCR ≤ 20.9 × 10⁻³), all surpassing recommended thresholds by UNSCEAR and ICRP. Absorbed dose rates ranged from 182 to 978 μSv/year, with annual effective dose equivalents showing wide spatial variability linked to Th-rich mineral zones. Mineralogical analysis identified phase-specific controls on radiological behavior: thorite and monazite drive thorium-related gamma emission and radon/thoron release, while zircon and fergusonite are responsible for uranium enrichment and decay chain disequilibrium. Even low-activity minerals like ferrocolumbite can contribute to localized radiation hotspots through co-enrichment in U and Th. These results highlight critical relationships between specific mineral phases and their associated radiological risks, offering a threefold contribution: i) Establishing a baseline for regional radioactivity mapping and U/Th enrichment; ii) Supporting the safe industrial use of pegmatitic materials by identifying high-risk phases; iii) Informing mining operations and processing strategies through mineralogically targeted radiation protection, including ventilation and shielding protocols. The study underscores the need for integrated radiological and mineralogical assessments in evaluating natural radiation hazards in granitic pegmatites and contributes to safer practices in resource utilization and environmental health protection.
| Technical Track | Nuclear Materials |
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