EFFECTS OF LEAD ON HISTOPATHOLOGY OF THE MUSCLES OF Clarias gariepinus JUVENILES

Abstract

The acute toxicity test of lead to Clarias gariepinus juveniles in the muscles and intestine of Clarias gariepinus juveniles was investigated using Standard Methods Bioassay APHA(2000). At the end of the 96hours the Muscles were rinsed in 10% formalin and preserved for further analysis. In this study, the LC50 values of Clarias gariepinus at 96h period was determined to be 50.12mg/ L. Results obtained from this study showed that lead (Pb(NO₃)₂) was absorbed in the muscles of the Clarias gariepinus juveniles during the 96hrsLC50 and extensive histological changes in the muscles exposed to the various lead concentrations of100mgL^-1, 75mgL^-1 and 50mgL^-1 was observed. The lead concentrations disturbed the homeostasis and led to physiological disorders in their functions and subsequently led to the death of the juvenile Clarias gariepinus. The muscles of Clarias gariepinus juveniles inhabiting the lead medium showed hemorrhage, hemosiderin, fatty degeneration and necrosis in connective tissue of hypodermal layer as well as degeneration, necrosis and edema in muscle fiber layer. The elimination of lead released into the environment through the discharge of lead-based ammunition and fishing tackle, lead as an anti-knock in petroleum, lead materials being used as water pipes for transport of municipal water, ...