Bioaccumulation of Heavy Metals in Liver of Albino Wistar Rats Exposed to Single and Heavy Metal Mixture

Heavy metals such as cadmium, lead and arsenic pose health hazards to animals and humans globally. These tend to bio-accumulate in body tissues andorgans and interfere with the functioning of vital cellular components. This study was conducted to evaluate the bioaccumulation of these metals in the liver of albino Wistar rats following a sub-chronic exposure to single and heavy metal mixture.Twenty mature male Albino Wistar rats weighing 192 -200g were randomly assigned into five groups of four rats each. Groups 1, 2, 3 and 4 were treated for 12 weeks with 60mg/kg bodyweight of lead acetate, 22.5 mg/kg bodyweight of cadmium dichloride, 18.8mg/kg bodyweight of arsenic trioxide, and group 4 treated with a mixture of lead acetate (60mg/kg bodyweight) cadmium dichloride (22.5 mg/kg body weight) and arsenic trioxide (18.8 mg/kg bodyweight) while group 5 served as the control. Both treated groups of animals and the control group were fed with rat chow and water throughout the experimental period. At termination, there was significant accumulation of metals in the liver of animals in the intoxicated groups when compared with the control group. Lead accumulation in the liver was found to be (41.41 + 33.72 kg/mg) in lead only group. Cadmium (Cd) accumulation in the liver was found to be 40.16 + 21.41 kg/mg in the Cadmium alone group. Arsenic (As) accumulation in the liver was found to be 26.59 + 10.12 kg/mg. The co-metal exposure group had Arsenic (As) concentration of 51.89 + 11.12kg/mg which was significantly (P < 0.05) á higher than that of As alone group and even other metals in the co-metal exposure group. There was a decrease in liver weight especially in As exposed groups and a greater decrease in the co-exposure group. Similarly, change in body weight was higher in the mixed heavy metal group followed by the arsenic exposed group.The elevated levels of these metals in the liver of experimental suggests potential toxic effects. A greater bioaccumulation of the metals in the co-exposure group suggests a synergistic interaction which implies increased toxicity. There is need to limit human exposure to these heavy metals.