Abstract
This study investigated the spatio-temporal variations of soil radionuclides in Chongqing (2016–2023) and assessed their associated health risks. Using descriptive, correlation, and mixed-effects model analyses, the activity concentrations and distribution of soil radionuclides (137Cs, 238U, ²³²Th, 226Ra and40 K) were examined. AEDE, Raeq, ELCR, ADR were calculated. Spatially, after controlling for temporal variation, the Urban New Area showed higher 226Ra and 238U than the Urban Core Area, while the Southeast Wuling Mountain Area had higher 226Ra, 137Cs and 238U. Temporally, after controlling for regional variation, 40K (2023, 2021), ²³²Th (2018–2023) and 238U (2021) all exhibited higher activity concentrations than in 2016. The calculated health risk indices (AEDE, Raeq, ELCR, ADR) were above global averages, indicating a need for targeted soil management. Specifically, levels of 226Ra and 238U in the Urban New Area, and of 226Ra, 137Cs, 232Th and 238U in the Southeast Wuling Mountain Area, require prioritization.
Data availability
The data that support the findings of this study are openly available from Annual Report of Chongqing’s Radiation Environment. Data are located in controlled access data storage at Chongqing Radiation Environment Supervision and Management Station, Chongqing, China. The data supporting the findings of this study are available from the corresponding author upon reasonable request.
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Acknowledgements
We would like to thank all staff who collected and detected samples and recorded and managed the data in the Chongqing Radiation Environment Supervision and Management Station, as well as all staff of subordinate institutions who provided assistance in this study.
Funding
This research was supported by the Chongqing Science and Health Joint medical research Project (No. 2025MSXM056). This research was also supported by the Chongqing Center for Disease Control, Prevention and Chongqing Jiulongpo District Center for Disease Control and Prevention, Chongqing Radiation Environment Supervision and Management Station and Chongqing Medical University.
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Qiang Huang and Xue Zhao cleaned and analyzed the data and wrote the initial draft. Jun Diao made significant contributions to conceive the study, revised the manuscript and submitted. Hengyan Du, Bo Fang, Qiang Tan, Qiuhao Zhang, Li Chen and Cuilan Fang reviewed the draft and provided critical suggestions, which helped improve the manuscript. All authors reviewed the manuscript and agreed on the final version of the manuscript to be submitted for publication.
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Huang, Q., Zhao, X., Fang, B. et al. Assessment of levels spatiotemporal differences and health risks of environmental radioactivity in the soil of Chongqing China. Sci Rep (2026). https://doi.org/10.1038/s41598-026-45598-8
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DOI: https://doi.org/10.1038/s41598-026-45598-8
