Abstract
The genotoxic effects of commonly used agricultural pesticides viz., carbosulfan, glyphosate, and atrazine, were evaluated in Channa punctatus (Pisces, Perciformes) using micronucleus (MN) test and induction of nuclear lesions (NL). The 96 h LC50 value were estimated by probit analysis as 0.27, 32.0 and 42.0 mg L−1, respectively, for carbosulfan, glyphosate, and atrazine using semi-static bioassays. Based on these values, three sublethal test concentrations of carbosulfan (0.07, 0.13, 0.20 mg L−1), glyphosate (8.1, 16.3, 24.4 mg L−1) and atrazine (10.6, 21.2, 31.8 mg L−1) corresponding to ¼, ½ and ¾ of the LC50 of the pesticides respectively, were selected for exposure for 96 h. Peripheral blood samplings were taken at intervals of 24 h for assessment of MN and NL frequencies. Considerably higher genotoxic damage was induced by carbosulfan as compared to glyphosate and atrazine. There were significant effects (p < 0.01) of concentrations in all the treated groups. The induction of MN and NL was highest at 96 h pesticide exposure at all test concentrations. The nuclear abnormalities recorded in this study, such as blebbed-, lobed-, notched- and bi-nuclei, other than micronuclei, are indicators of genotoxic damage.
Acknowledgements
The authors wish to thank the Academy of Science for Developing World (TWAS) and the Department of Biotechnology, the Ministry of Science and Technology, Government of India (DBT) for the post-doctoral fellowship (PDF) granted to the first author and the financial assistance received. We also thank the Director, National Bureau of Fish Genetic Resources, Lucknow (India) for providing support, materials and equipment for the work.