Toxicity and Histopathological Effects of Portland Cement Powder in Solution on the Structure of the Gill and Liver Tissues of the Nile Tilapia, Oreochromis niloticu
The toxicity and histopathological effects of Portland cement powder in solution on the gill and liver tissues of the Nile tilapia, Oreochromis niloticu were determined in this study. The fish were exposed to four (4) acute concentrations (312.50, 156.80, 78.20 and 19.60mg/L) for 96 hours. The 96 hours LC50 of the toxicant to the test fish was 41.21mg/L while the upper and lower 95% confidence limit were 48.63 and 34.92mg/L respectively There was very strong and positive correlation (r= 0.94) between logarithm concentration of Portland cement powder in solution and Probit mortality. Similarly, the determined 96 hours LT50 was 11.40, 18.30 and 58.20 hours for 312.5, 156.3 and 78.2mg/L of Portland cement powder in solution on the test fish Oreochromis niloticus respectively. The most common gill changes at all doses of Portland cement powder in solution were destruction of gill lamella, epithelial hyperplasia and epithelial hypertrophy. Hepatic lesions in the liver tissues of fish exposed to Portland cement powder in solution were characterized by degeneration of hepatocyte, vascuolization of cell cytoplasm, fatty degeneration and hypertrophy of hepatocytes. Histological comparison of tissues indicated that most damage occurred in the gill rather than in the liver.
Keywords: Portland cement powder, Oreochromis niloticu, Toxicity, Histopathology, gill, liver
Tropical Freshwater Biology Vol. 17 (1) 2008: pp. 25-36