Natural radionuclides in flood-affected rice agroecosystems: distribution patterns, transfer dynamics, and radiological implications

Authors

  • J. K. Simon
    National Open University of Nigeria, Plot 91, Cadastral Zone, Nnamdi Azikiwe Express Way, Jabi, Abuja, P.M.B 581, Nigeria
  • E. P. Inyang
    National Open University of Nigeria, Plot 91, Cadastral Zone, Nnamdi Azikiwe Express Way, Jabi, Abuja, P.M.B 581, Nigeria
  • H. G. Kama
    National Open University of Nigeria, Plot 91, Cadastral Zone, Nnamdi Azikiwe Express Way, Jabi, Abuja, P.M.B 581, Nigeria
  • S. Bello
    Umaru Musa Yar’adua University, Dutsin-ma Road, Katsina, Katsina State, P.M.B. 2218, Nigeria
  • A. G. Yisa
    National Open University of Nigeria, Plot 91, Cadastral Zone, Nnamdi Azikiwe Express Way, Jabi, Abuja, P.M.B 581, Nigeria
  • J. A. Yusuf
    Centre for Energy Research and Training, Ahmadu Bello University, Sokoto Road, Samaru, Zaria, Kaduna State, P.M.B. 1045, Nigeria

Keywords:

Flooding, Natural radionuclides, Rice agroecosystems, Soil-rice transfer factor, Radiological risk

Abstract

This study assessed the redistribution of natural radionuclides and associated radiological risks in flood-affected rice agroecosystems of Hadejia, Jigawa State, Nigeria. Radiation surveys and sample collection were conducted shortly after floodwater recession. A total of 50 soil and rice samples were analyzed using gamma spectrometry. The mean activity concentrations of 226Ra, 232Th, and 40K were 11.58 ± 0.41, 16.32 ± 1.28, and 470.24 ± 25.13 Bq/kg in soil, and 2.01 ± 0.15, 2.24 ± 0.17, and 130.22 ± 2.19 Bq/kg in rice, respectively. The corresponding radiological indices due to soil exposure were below world averages and recommended safety limits. Soil-to-rice transfer factors followed the order 40K (0.30) > 226Ra (0.18) > 232Th (0.17), consistent with the existing literature. The annual effective dose from rice consumption (0.06 ± 0.01 mSv/y) was below the public dose constraint of 0.3 mSv/y. Regression analysis showed strong dependence of 226Ra uptake on soil concentration (R2 = 0.815), weak correlation for 232Th (R2 = 0.304), and no significant relationship for 40K (R2 = 0.006). Spatial and normalized analyses revealed localized hotspots linked to flood-induced sediment deposition. The radiological risk was low, although continued monitoring is recommended.

Dimensions

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fig 4

Published

2026-07-22

How to Cite

Natural radionuclides in flood-affected rice agroecosystems: distribution patterns, transfer dynamics, and radiological implications. (2026). African Scientific Reports, 5(2), 539. https://doi.org/10.46481/asr.2026.5.2.539

Issue

Volume 5, Issue 2, August 2026

Section

PHYSICS SECTION
Copyright & Licensing

Copyright (c) 2026 J. K. Simon, E. P. Inyang, H. G. Kama, S. Bello, A. G. Yisa, J. A. Yusuf

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

Natural radionuclides in flood-affected rice agroecosystems: distribution patterns, transfer dynamics, and radiological implications. (2026). African Scientific Reports, 5(2), 539. https://doi.org/10.46481/asr.2026.5.2.539

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