Unwholesome Herbal Medicines Marketed in Enugu Metropolis, Enugu State, South Eastern Nigeria: Public Health Implications

Abstract

Background: The public health implications associated with consumption of unwholesome herbal medicines, food substances and water are well documented. This study brought forth the case of heavy metal and microbial contamination as well as phyto-chemical composition of some herbal medicines marketed in Enugu Metropolis, Enugu State, Nigeria.   Methods: Ten herbal medicines were randomly purchased from herbal medicine vendors in the streets and markets in Enugu, Nigeria. The samples were labeled A-J, and were in triplicates. The heavy metal contents (Pb, Cu, Cd, Zn, Ni, Cr, Fe, Hg, As, Se) were determined using Atomic Absorption Spectrophotometer. The bacterial load was determined by the agar dilution technique and the phyto-chemical constituents of the medicines were determined following standard methods.   Results: Lead and cadmium were present in all the medicine samples at concentrations significantly higher (p<0.05) than the recommended standards of American Herbal Products Association, AHPA/WHO standards. The Cr, Fe, and Ni concentrations in 70%, 50% and 40% of the samples respectively, were significantly higher (p<0.05) than the AHPA/WHO standards. Bacteria and fungi were present in the herbal medicines in varying concentrations. The phyto-chemical constituents of the herbal medicines were carbohydrates, alkaloids, tannins, flavonoids, saponnins, steroids, terpernoids, proteins, and glycosides in varying quantitative compositions across the herbal medicines.   Interpretation: The phyto-constituents identified have medicinal values to justify for the ethno-medicinal uses claimed by the manufacturers. However, the heavy metals and microbial contaminants of all the medicines pose serious public health challenges and require the attention of the national drug regulatory authorities.