Assessment of DNA damage due to water pollution in selected fish species Chana punctatus & Shizothorax pelageostomus"

Assessment of physico-chemical and heavy metals pollution was analyzed in River Kabul and their impact was studied on DNA damage in different tissues of selected fish species from the river. The water samples collected from low, medium and high polluted sites of River Kabul were analyzed for physico-chemical parameters and presence of heavy metals (Zn, Ni, Cl, Cr, Cu, Cd, pb, Mn, Fe and Hg), while fish samples were collected from highly polluted belt of the river Kabul, KPK, Pakistan at different times. The collected fishes (Shizothorax pelageostomus, Chana punctatus) were dissected and five different tissues like intestine, gills, skin and liver were taken out. Alkaline comet assay was performed to monitor any mutation in the genomic DNA. Comet tail lengths (consisting of nuclear region and tail) were scored visually into 5 Comet Classes. The overall order of DNA damage in different organs of fishes was in the sequence of blood, skin, gills, intestine. Liver was more affected in Shizothorax pelageostomus than Chana punctatus. This shows that highest level of the DNA damage was found in the intestine followed by the blood, skin, and liver followed by gills. Similarly the highest level of the DNA damage was observed in Shizothorax pelageostomus followed by Chana punctatus. At the organs level, DNA damage in Chana punctatus was most in intestine followed by blood, skin, liver and gills. Similarly in Shizothorax pelageostomus it was is most in intestine followed by skin, blood, liver and gills. This study indicated the genotoxicological effects of heavy metals like Zn, Ni, Cr, Cu, Cd, Pb, Fe, Mn and Hg in blood, intestine, skin, liver and gills of two selected fish species.