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Abstract

The present study was assessed to determine the acute toxicity and changes in oxidative stress enzymes of Tubifex tubifex and to evaluate the acute toxicity and changes in oxidative stress enzymes, hematological and biochemical parameters, growth parameters of freshwater fish Oreochromis mossambicus during chronic exposure to Quinalphos. The study reveals that the 96h LC50 value of Quinalphos to T. tubifex and O. mossumbicus were 6.28 μg/l and 5.35 μg/l respectively. Besides, the exposed worms and fish also exhibited erratic behavioral responses at the acute level. Acute exposure of Quinalphos to T. tubifex induces alterations in oxidative stress enzymes including catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), malondialdehyde (MDA), reduced glutathione (GSH), and glutathione peroxidase (GPx). Additionally, chronic exposure of Quinalphos to O. mossumbicus showed increasing the levels of liver CAT, SOD, GST, MDA, aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Sublethal levels of Quinalphos elicited substantial changes in protein, glucose, albumin and creatinine of fish in compare to control. Quinalphos also effects different growth (GSI, SGR, FCR) and hematological parameters (the red blood cell, haemoglobin and haematocrit) of treated fish. Moreover, by using integrated biomarker response (IBR) and biomarker response index (BRI) the change in the health status of pesticide exposed fish was determined. These results indicate that Quinalphos alters the survivability and behavioral responses of T. tubifex and O. mossambicus at the acute level and changes the oxidative stress biomarkers, biochemical and hematological parameters of the fish during chronic exposure.