A global meta-analysis of radiological contamination in soils and Monte Carlo simulation-oriented hazards evaluation.

Soil pollution caused by radionuclides has become a global concern. However, previous research has mostly focused on specific sites or limited locations, which may not provide a comprehensive understanding of the overall soil pollution situation worldwide. To address this gap, this study collected and examined data from published articles between 2010 and 2023. The research examined levels of ²²⁶Ra, ^{232 T}h, ⁴⁰K, ²³⁸U, and ¹³⁷Cs in soils globally and used meta-analysis to assess the radiological hazards and health risks associated with radionuclide contamination. The average content of ²²⁶Ra, ²³²Th, ⁴⁰K, and ²³⁸U was significantly higher than the permissible values, by approximately 4.21, 3.80, 1.20, and 9.78 times, respectively. The studied soils were found to have moderate to heavy contamination levels of ²²⁶Ra, ²³²Th, and ²³⁸U based on the geoaccumulation index. Additionally, they exhibited heavy contamination with ⁴⁰K. Several radiological hazard indices, such as the internal hazard index (H in), absorbed gamma dose rates (D out and D in), annual effective dose rates (E aed out and E aed in), activity utilization index (AUI), and excess lifetime cancer risk (ELCR out and ELCR in), were higher than recommended limits. Monte Carlo simulation-based analysis revealed elevated radiological risks, with the 95th percentile values for Ra eq , D out , D in , ELCR out , and ELCR in exceeding respective threshold values. These findings provide valuable insights for policymakers to develop effective strategies for minimizing global exposure to radionuclides in soil. [Display omitted] • Total levels of five radionuclides in soils were reviewed by a global meta-analysis. • Approximately 88.02% of soil sampling sites exhibited significant contamination with ²³²Th. • Radionuclide contamination in global soils posed possible lifetime cancer risks. • Monte Carlo simulation-oriented D out , D in , ELCR out , and ELCR in showed radiological hazards. [ABSTRACT FROM AUTHOR]