Document Type : Original Article


1 Department of Pharmacology and Toxicology, Faculty of Pharmacy, Federal University, Oye_Ekiti, Nigeria

2 ManProject Foundation, PortHarcourt, Nigeria

3 Department of Pharmacology and Toxicology, Faculty of Pharmacy, Bingham University, Karu, Nigeria

4 Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Uyo, Nigeria

5 Department of Human Physiology, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, Nigeria

6 Department of Pharmacology, Therapeutics, and Toxicology, Lagos State University College of Medicine, Ikeja, Lagos, Nigeria



Background: Heavy metal contaminations of herbal formulations have constituted a public health challenge in the sub-Saharan Africa region and even in some developed nations. The study aimed to evaluate the public health concerns of chronic exposure to a polyherbal drug suspected to contain heavy metals. Methods: This is an experimental study. Heavy metals were measured using Solaar-Thermo-Elemental Atomic Absorption Spectrophotometer. Human health risk assessment was estimated by calculating the estimated daily intake, target, hazard quotient (THQ), health index (HI), carcinogenic risk (CR) of exposure to the polyherbal drug.
Results: The results showed the presence of metals in this order: Cd<Hg<As<Pb<Zn<Mn<Cu<Ni<Cr 1; HI for adolescents, adults, and geriatrics were >1. Ni and Cr had the highest cancer risk; total cancer risk was above the safe limit.

Conclusion: Since herbal medicines/dietary supplements are not under compulsory regulation by international, national, and local health regulatory authorities, these products must be manufactured using the highest manufacturing standards to ensure their safety among the end-users. Our findings suggest the likelihood of significant non-carcinogenic adverse health effects among adolescents, adults, and the geriatric population due to exposure to a mix of toxic metals, necessitating utmost caution on its chronic use. If policy formulations and implementations regarding the safety of herbal medicines and associated products prior to their circulation are ensured, public health will be protected and significantly improved.


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