Induction of Genetic Alterations and Oxidative Stress in Giant African Land Snail (Limicolaria aurora) Exposed to Municipal Waste Leachate

Videla C.G., Las Heras M., Ayala Y., San Román E.

Abstract: Uncontrolled waste disposal has continuously threatened the health of the surrounding environment through the leaching of hazardous xenobiotics. Systemic toxicity and genotoxicity potential of waste leachates from Onitsha municipal dumpsite were investigated in giant African land snail (Limicolaria aurora) through oxidative stress biomarker and micronucleus test assessment respectively. Physicochemical indices were evaluated in the leachate following standard protocols. Snails were exposed to different concentrations (0, 6.25, 12.5, 25.0 and 50.0%) of waste leachate for 21 days; oxidative stress biomarkers and micronucleus  analysis performed on snail digestive gland and hemocyte respectively. The leachate induced dose-duration dependent increase (P< 0.05) in Superoxide dismutase, Catalase, malondialdehyde and Glutathione peroxidase levels with associated decrease in total protein concentrations in the exposed snails compared to the control. Similarly, the frequency of micronucleus and other nuclear abnormalities shows concentration dependent increase (P< 0.05) in treated groups. This observed genotoxic effect might be induced by the oxidative stress, via the production of reactive oxygen species. This shows that waste leachate contains hazardous and genotoxic compounds capable of inducing oxidative stress and DNA damage. Therefore, continuous exposure of waste leachate into the environment could pose a grave health risk to the surrounding biota, humans included.

Keywords: Biochemical, Giant African Land Snail, Micronucleus, Nigeria, Waste Pollution.