Abstract :
The cichlid fish Pseudetroplus maculatus was used to evaluate the sublethal toxic effects of estrogenic environmental contaminant, bisphenol A. Fish were exposed to sublethal concentration (648 μg/L) of bisphenol A for shot-term (24, 72 and 96 h) and long-term (7 and 15 days) durations along with control groups. The rate of oxygen consumption was found to be decreased as the treatment period increases and this could be due to the accumulation of mucous on gills or shrinkage of the respiratory epithelium as an outcome of contaminant toxicity. Haematological parameter such as erythrocyte count was decreased while total leukocyte count increased significantly in time-dependant manner. The significant decrease in erythrocyte count indicates destruction of RBC or reduction in erythropoietic activity as a result of bisphenol A exposure. Increase in total leukocyte count is a sign of hypersensitivity that convey immunological reactions to produce antibodies in order to overcome the stress. Histological examination revealed that bisphenol A exposure caused upliftment of gill epithelium, hyperplasia of gill arches, aneurysm and absence of secondary lamellae. Hepatic cells showed vacuolization and degeneration of cytoplasm after the exposure to bisphenol A when compared to the control tissues. Thus the results of the present study clearly demonstrate that exposure of bisphenol A at sublethal concentration to the fish may provoke adverse effects on vital organs.
Keyword :
Bisphenol A, Pseudetroplus maculatus, Oxygen consumption, Haematology, Histology, Gill, Liver