Genotoxicity evaluation of 1,2 dichlorobenzene in the Indian major carp, Catla catla L. using alkaline comet assay

The genotoxic effect of 1,2 dichlorobenzene (1,2 DCB), a volatile organic compound in the Indian Major Carp, Catla catla L. was assessed using the alkaline comet assay in the gills and blood. Fish were exposed to various sub-lethal concentrations of 1,2 DCB in vivo. At 24 h, DNA damage scores (expressed as arbitrary units) increased at 0.35 and 0.7 mg/L whereas at 28 days, there was a statistically significant increase in the DNA damage score at all the doses tested (0.175, 0.23, 0.35 and 0.7 mg/L). When the DNA damage scores were considered in the blood samples, the trend was similar to that observed in the gills - significant increase at 0.35 and 0.7 mg/L at 24 h and at all doses at 28 days. The results indicate that 1,2 DCB induces genotoxicity in the form of strand breaks in the DNA of fish as evidenced by the alkaline comet assay.