Heavy metals are metals with a specific gravity of 5 g/cm 3 or above. 1 They have a high atomic weight and are at least 5 times denser than water. The metals are toxic and have been linked with the increasing prevalence of chronic diseases worldwide. Heavy metals of primary concern to living organisms owing to their toxicological properties include lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), barium (Ba), zinc (Zn), copper (Cu), manganese (Mn) and iron (Fe). 2 Even at minute quantities, these metals can induce hematological, biochemical, histopathological, and genetic diseases, among others. However, the severity of damage caused by these metals depends on their form, concentration, duration of exposure, route of exposure, as well as the age, gender, genetics, and diets of exposed individuals. 3 Direct human exposure to heavy metals may occur through natural sources such as weathering and volcanic eruptions. 4 It may also occur from anthropogenic activities such as mining, oil refining, use of leaded petrol, airborne dust, arbitrary discarding and burning of toxic waste, among others. 5 Indirect exposure occurs when heavy metals in the environment build up in the