ASSESSMENT OF HEAVY METALS ACCUMULATION AND ASSOCIATED HEALTH RISKS ON MORINGA OLEIFERA FROM SOUTHERN KADUNA, NIGERIA

Abstract

Minerals, proteins, vitamins and phytocompounds abound in Moringa oleifera. A significant species of medicinal tree belonging to the Moringaceae family. Moringa oleifera leaves obtained from Ambam (Jama'a LGA) and Maro (Kajuru LGA) in Kaduna State, Nigeria, were subjected to an AAS analysis to determine the content of specific heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) and associated health risk. Fe 7.627 mg/kg, Pb 0.598 mg/kg, Ni 0.454 mg/kg, Mn 0.451 mg/kg, Zn 0.333 mg/kg, Cu 0.286 mg/kg, and Cr 0.191 mg/kg were the metal concentrations in Moringa oleifera at Ambam. The concentration followed the order Fe ˃ Pb ˃ Ni ˃ Mn ˃ Zn ˃ Cu, ˃ Cr ˃ Cd.  Nonetheless, Maro metal concentration trend follows a different order: Cd has the lowest concentration at 0.035 mg/kg, followed by Fe (3.453 mg/kg), Mn (0.601 mg/kg), Pb (0.505 mg/kg), Ni (0.327 mg/kg), Zn (0.262 mg/kg), Cu (0.221 mg/kg), and Cr (0.155 mg/kg). Ambam and Maro have Cd, Ni, and Mn concentrations below the WHO recommended acceptable range. While Pb is over the WHO established permitted limit, the concentration of Cr in both Ambam and Maro was found to be within the limit. Consuming Moringa oleifera from this area may provide a risk of cancer because the THQ values of Cd, Cu, Fe, Ni, and Pb were found to be greater than 1. The use of Moringa oleifera in the study regions may have a negative impact on the health of the adult population, as indicated by the health index (HI) values of 43.7222 and 35.2028 at Ambam and Maro, respectively.