HEAVY METAL CONCENTRATION

Vegetables are consumed in both the developing and developed countries of the world due to their high nutritive values, however they also contain some high levels of toxic substances including metals.This study assessed the comparative concentrations of selected heavy metals:cadmium (Cd), lead (Pb), nickel (Ni), zinc (Zn), and copper (Cu) in four commonly consumed leafy vegetables: fluted pumpkin (Telfairia occidentalis), bitter leaf (Vernonia amygdalina), water leaf (Talinum triangulare), and scent leaf (Ocimum gratissimum) cultivated in polluted (Oluku) and unpolluted (Iyowa) sites in Benin City, Edo State, Nigeria. Samples were analysed using Atomic Absorption Spectrophotometry (AAS), and results were compared with FAO/WHO permissible limits. The concentrations of all heavy metals were below recommended safety thresholds, with the general trend of accumulation being polluted site > unpolluted site. Statistical analysis (p < 0.05) revealed significant variations for some metals, particularly Zn, Cd, and Cu, across the two locations. Bitter leaf and scent leaf exhibited higher tendencies for metal accumulation compared to other vegetables. Although all concentrations were within safe limits, continuous cultivation near polluted areas may lead to long-term contamination risks. The findings highlight the influence of anthropogenic activities such as waste disposal and vehicular emissions on metal uptake in vegetables and underscore the need for regular environmental monitoring, improved waste management, and public awareness to ensure food safety