Department of Zoology, Faculty of Science, University of Lagos, Akoka, Lagos, Nigeria
Otitoloju, A., Department of Zoology, Faculty of Science, University of Lagos, Akoka, Lagos, Nigeria; Olagoke, O., Department of Zoology, Faculty of Science, University of Lagos, Akoka, Lagos, Nigeria
The toxicological evaluations of crude oil, xylene, toluene and benzene were carried out against juvenile stages of Clarias gariepinus. On the basis of LC 50 value, benzene (0.017 ml/l) was found to be the most toxic followed by xylene (0.086 ml/l), toluene (0.398 ml/l) and crude oil (2.219 ml/l) was the least toxic. The results of the lipid peroxidation assay showed that the level of malonaldehyde (MDA) in liver and gills of fish exposed to all the test chemicals increased significantly (P < 0.05) when compared to control. Measurement of activities of antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) in liver and gill of fishes exposed to sublethal concentration of the test chemicals over a 28-day period was found to decrease significantly (P < 0.05) when compared to control. The observed reduction in the activities of antioxidant defense enzymes such as SOD, CAT and GST in conjunction with an increase in MDA levels in the gill and liver tissues of test animals exposed to aromatic hydrocarbon compounds were recommended as a good battery of biomarkers for early detection of pollution during biomonitoring programmes. © 2011 Springer Science+Business Media B.V.
Antioxidant defense; Antioxidant enzyme; Biomonitoring; Clarias gariepinus; Early detection; Glutathione-S-transferase; Hydrocarbon compounds; Lipid peroxidation; Liver tissue; Malonaldehyde; Superoxide dismutases; Toxicological evaluation; Aldehydes; Animals; Aromatic compounds; Aromatization; Benzene; Computer system firewalls; Crude oil; Enzymes; Hydrocarbons; Oxidation; Oxidative stress; Oxygen; Pollution detection; Polycyclic aromatic hydrocarbons; Tissue; Toluene; Toxic materials; Xylene; Catalysts; benzene; biological marker; catalase; glutathione transferase; malonaldehyde; petroleum; polycyclic aromatic hydrocarbon; superoxide dismutase; toluene; xylene; bioassay; biomarker; biomonitoring; enzyme activity; fish; lipid; oxidation; PAH; pollution exposure; toxicity test; toxicology; acclimatization; animal experiment; animal tissue; article; biological monitoring; Clarias gariepinus; concentration (parameters); controlled study; environmental exposure; environmental monitoring; enzyme activity; enzyme inhibition; fingerling; gill; LC 50; lipid peroxidation; liver toxicity; nonhuman; oxidative stress; physical chemistry; signal transduction; Siluriformes; toxicity testing; Animals; Biological Markers; Catalase; Catfishes; Environmental Monitoring; Gills; Glutathione Transferase; Lipid Peroxidation; Liver; Nigeria; Petroleum Pollution; Polycyclic Hydrocarbons, Aromatic; Superoxide Dismutase; Water Pollutants, Chemical; Animalia; Clarias gariepinus; Pisces