Genotoxicity evaluation of Bifenthrin pyrethroid insecticide to freshwater fish Danio rerio using the alkaline comet assay in gill tissue

E.G. Sreenivasula Reddy; T. Nageswara Rao; and Kappari. Sharadha Devi

Volume : III, Issue : XII, December - 2013

Genotoxicity evaluation of Bifenthrin pyrethroid insecticide to freshwater fish Danio rerio using the alkaline comet assay in gill tissue

E. G. Sreenivasula Reddy, T. Nageswara Rao, And Kappari. Sharadha Devi

Abstract :

The DNA damaging potential of pyrethroid insecticide bifenthrin (technical grade– purity 95%) to the fresh water fish, Danio rerio, was assessed using the alkaline comet assay. Bifenthrin technical being insoluble in water was dissolved in DiMethylSulfOxide and tested at a maximum concentration of 3.18ug/L. Two fish from each group were sacrificed at the end of weeks 1, 2 and 3 following exposure and the gill tissues were processed for comet assay. A reversal group was maintained for period of 10 days without treatment and later sacrificed and processed similarly. Comets were scored visually based on their tail intensity (0 –Undamaged, 1–mild, 2–moderate, 3– severe and 4–extensive). Cells were categorized into various degrees of damage according to the extent of DNA migration. DNA damage was observed from the first week of exposure, which increased with duration of exposure. However, in the reversal group, the percentage of DNA damage was statistically lower suggesting effect on DNA repair. The study clearly demonstrated an elevated DNA damage in cells from gills of Danio rerio due to bifenthrin, which is reversible. Further, the results presented here show that gills can be used as a tissue to explore chemical induced DNA damage in fish. /* Style Definitions */ table.MsoNormalTable {mso–style–name:"Table Normal"; mso–tstyle–rowband–size:0; mso–tstyle–colband–size:0; mso–style–noshow:yes; mso–style–priority:99; mso–style–qformat:yes; mso–style–parent:""; mso–padding–alt:0in 5.4pt 0in 5.4pt; mso–para–margin:0in; mso–para–margin–bottom:.0001pt; mso–pagination:widow–orphan; font–size:10.0pt; font–family:"Times New Roman","serif";}