Abstract
Polychlorinated biphenyls (PCBs) remain a global concern due to their environmental persistence and toxicity. However, their distribution in industrial and residential areas in Nigeria is insufficiently documented. This study investigated PCB concentrations in soils and commonly consumed plants from five sites around industrial areas in Koko Town, Delta State. Soil and plant samples were extracted using a Soxhlet extraction method and analyzed via GC-MS following the USEPA method 3540 C. Mean PCB concentrations were significantly higher in plants (20.75 mg kg− 1) than in soils (10.32 mg kg− 1), with both matrices exceeding the WHO recommended limits. PCB accumulation was highest in Pueraria phaseoloides, followed by Ceiba pentandra, Chromolaena odorata, Vermonia amygdalina, and Musa sapientum. The estimated daily intake (EDI) for adults and children exceeded the USEPA reference dose (0.000007 mg kg− 1) with a hazard ratio > 1, indicating a notable health risk, particularly for children. The findings underscore the need for regular monitoring and mitigative strategies for communities vulnerable to PCB pollution.
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Data availability
Data are available upon request from the corresponding author.
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Acknowledgements
The authors are grateful to the Herbarium Unit, University of Benin where identification of plant species was carried out by Amaka Michael and Akinnibosun H. Adewale.
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Amaka Michael, prepared the manuscript, interpreted the results and wrote the paper, Abraham O. Ekperusi revised the work, Ndu P. Okeke initiated the study, and Anthonia E. Gbuvboro wrote the summary. All authors read and approve the final manuscript.
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Michael, A., Ekperusi, A.O., Okeke, N.P. et al. Distribution and human health risk of polychlorinated biphenyls in soil and plants in Koko Town, Delta State, Nigeria.
Sci Rep (2025). https://doi.org/10.1038/s41598-025-33241-x
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DOI: https://doi.org/10.1038/s41598-025-33241-x
Keywords
- Polychlorinated biphenyls
- Bioaccumulation
- Niger delta
- Human exposure
- Risk assessment
Source: Ecology - nature.com
