Effect of Raw Leachate on Gills and Liver of Juvenile African catfish (Clarias gariepinus)

Abstract

The effect of toxicity of raw leachate obtained from dumpsites on Clarias gariepinus (C. gariepinus) (n = 6) was studied under laboratory conditions with the aim of establishing its effect on the gills and liver of C. gariepinus. The physico-parameters (pH, conductivity, total dissolved solid, salinity, temperature, dissolved oxygen, chemical oxygen demand, biological oxygen demand) and heavy metals (lead, cadmium, chromium, copper and nickel) were also analyzed using standard methods. The results of physico-chemical analyses of leachate showed contamination of organics, salts and heavy metals. Furthermore, lethal concentration (LC₅₀) of leachate effluent on C. gariepinus was determined using probit method to ascertain fish mortality.  Result revealed that C. gariepinus exposed to different concentration of raw leachate recorded increasing mortality of 0, 0, 1, 4 and 5 at 0%, 5%, 10%, 25% and 75% concentration respectively for a period of 96 hours. The colour and behavioral responses were normal in the control experiment. But there were abnormal behavior including erratic swimming and quick sudden movements in concentrated samples. Also, results of the histopathological analysis showed alterations in the gills and liver. The study concluded that raw leachate is toxic to C. gariepinus, and therefore recommends for adjusting factors enhancing anaerobic biodegradation that lead to leachate stabilization as well as treatment and monitoring of effluent released into water bodies.