Genotoxic Consequences in Common Grass Carp (Ctenopharyngodon idella Valenciennes, 1844) Exposed to Selected Toxic Metals

The primary aim of the current study was to recognize the biomarker approach as the finest tool to identify the geno-toxicological effects of copper, chromium, and lead inside the blood of grass carp using micronucleus test and comet assay. The induced micronuclei frequency in response to the administered concentrations of LC50 metals was discovered in the erythrocytes of metal-exposed fish at four-time intervals. The genotoxic effect of these metals with respect to the formation of micronuclei was ranked as chromium > lead > copper. Percentages of other cellular and nuclear abnormalities were also determined in the exposed blood films. Equally, the genotoxic studies in terms of comet assay in fish blood revealed significant deviations p < 0.05 against each of the studied metal at their respective time interval as compared with the healthy fish group. However, induced frequency of micronuclei and the calculated DNA damage were not found to be duration dependent. Consequently, copper, chromium, and lead have been explored as cytotoxic elements that can be responsible for inducing genotoxic effects in fish existing aquatic habitats.