Research Article

TOXICOLOGICAL RISKS AND FOOD SAFETY COMPLIANCE: PROTECTING PUBLIC HEALTH FROM HEAVY METAL CONTAMINATION IN THE OYO STATE VEGETABLE SUPPLY CHAIN

Gbenga Tosin Adedeji1*, Taofik Olatunji Bankole1, Ayodeji Bidemi Bakare2, Bamidele Adegbola Alabi3, Folakemi Helen Olagoke4, Nafisat Olaitan Adebayo1, Sarah D. ADEDEJI5
1 Department of Public Health, Osun State University, Osogbo
2 Department of Environmental Health, Federal University of Health Sciences, Ila-orangun
3 Department of Science Technology and Mathematics Education, Osun State University, Osogbo
4 Institute of Ecology, Obafemi Awolowo University, Ile-Ife
5 Department of Nursing Science, Obafemi Awolowo University, Ile-Ife
* Corresponding author: adedejitosin708@gmail.com
Published: Jun, 2026
DOI: 10.66884/kesj.2026.y1vev6i0
Pages: 216-229
Views: 85
Downloads: 42

Abstract

Purpose: The consumption of vegetables, particularly leafy greens like Amaranthus hybridus (efo-tete), is a significant aspect of dietary habits in many regions, including Southwest, Nigeria. Meanwhile, the prevalence of environmental contaminants (mercury, cadmium, lead) in agricultural soils poses a serious health risk to consumers.

Design/methodology/approach: To achieve this aim, evaluations were carried out on the levels and translocation of three heavy metals in soil and plant samples from the two local government areas (Oluyole and Akinyele) in Oyo State, Nigeria. The study design was purely experimental; sample size was six (6) different farm locations in Oluyole and Akinyele Local Government Area. The apparatus and instruments that was used include, Distilled water, weighing balance, and Atomic Absorption Spectrophotometer (AAS) for measuring heavy metal concentrations in the vegetable’s compartments. Data was analyzed using IBM Statistical Product and Service Solutions (SPSS), version 27.0.

Findings: Mercury showed the highest bioaccumulation levels in Amaranthus hybridus roots from Oluyole (0.027 mg/kg), significantly higher than in Akinyele (0.005 mg/kg). Cadmium concentrations were relatively similar across both study sites, averaging around 0.020 mg/kg in roots. There was higher concentration of Lead in Akinyele leaf samples (0.009 mg/kg) than Oluyole (0.006 mg/kg) showing differences across the study sites.

Research limitations/Implications: The major limitation of the study was time constraint to explore the research to phytoremediation experiments. The contribution to knowledge is that this study established the potential health risk of bioaccumulation of heavy metals in the consumption of leafy vegetables (Amaranthus hybridus).

Practical implications: Based on the findings, the study recommended across relevant stakeholders: Government-should promote awareness campaign about the risks associated with heavy metals consumption and the importance of food safety. Furthermore, to the farmers- they should adopt sustainable practices that reduce heavy metal accumulation through phytoremediation to clean up pollutants from the soil.

Originality/value: The study confirms the presence of bioaccumulated heavy metals in Amaranthus hybridus, raising significant public health concerns, particularly for communities reliant on locally grown vegetables.

Keywords

Bioaccumulation; Heavy metals; Amaranthus hybridus Transfer factor Health risk

References

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How to Cite

Adedeji, G. T., Bankole, T. O., Bakare, A. B., Alabi, B. A., Olagoke, F. H., Adebayo, N. O., & ADEDEJI, S. D. (2026). TOXICOLOGICAL RISKS AND FOOD SAFETY COMPLIANCE: PROTECTING PUBLIC HEALTH FROM HEAVY METAL CONTAMINATION IN THE OYO STATE VEGETABLE SUPPLY CHAIN. Kaduna State University Environmental Sciences Journal, 6(1), 216-229. https://doi.org/10.66884/kesj.2026.y1vev6i0

G. T. Adedeji, T. O. Bankole, A. B. Bakare, B. A. Alabi, F. H. Olagoke, N. O. Adebayo, and S. D. ADEDEJI, "TOXICOLOGICAL RISKS AND FOOD SAFETY COMPLIANCE: PROTECTING PUBLIC HEALTH FROM HEAVY METAL CONTAMINATION IN THE OYO STATE VEGETABLE SUPPLY CHAIN," Kaduna State University Environmental Sciences Journal, vol. 6, no. 1, pp. 216-229, June 2026. doi: 10.66884/kesj.2026.y1vev6i0

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