Investigating some Selected Heavy Metals and Micronutrients Levels in Herbal Preparation Marketed in Nigeria: A Pilot Study

Background: The use of herbal remedies has become a global practice. The role of several inorganic elements in the maintenance of normal body metabolism has been documented. Previous studies examining trace metals content of approved herbal preparations have focused mostly on heavy metals with little or no attention given to micronutrients. A pilot study on selected trace metal and micronutrient constituents of one of the herbal products regularly consumed by the populace was conducted to bridge this gap.
Methods: A well known herbal product Yoyo bitters (YYB) was purchased from one of the pharmaceutical shops within the Metropolis. As an inclusion criterion, the product was ascertained to have been registered with the National Agency for Food, Drug Administration and Control (NAFDAC). The manufactured and expiry dates of the products were inspected and all were confirmed to be within the acceptable time frame. In all, fifteen (15) bottles of the product, each containing a 100 ml of syrup were purchased and levels of Iron, Copper, Zinc, Lead and Iodine were determined using standard method. Data obtained were compared with United States Environmental Protection Agency (USEPA) and the World Health Organization (WHO) recommended allowable intake for these metals.
Results: Showed that the selected herbal remedy contained mean (±SD) levels of: Iron 12600 (350) µg/L); Copper 200 (0) µg/L); Zinc 300 (0) µg/L); Lead 400 (10) µg/L) and Iodine 145500 (3560) µg/L respectively.
Conclusion: While the herbal product investigated contained allowable levels of copper and lead, high levels of iodine and iron were detected. This might imply that iodine and iron toxicities could be a likely adverse effect associated with the use of this product. The need to exercise caution to avoid possible Iodine and Iron overload due to excessive consumption of this herbal product was highlighted in this work.