Assessment of genotoxicity induced by helminthes parasites in freshwater fishes of river Ganges

Several parasites have been shown to induce genotoxicity in humans and fish are important intermediate hosts for completing the life cycle of many parasites, posing a huge economic loss worldwide through the ecosystem food chain. In the present study, we assessed the genotoxic potential of helminth Rostellascaris sp. through a benchmark of comet assay and micronucleus (MNi) tests on the hepatocytes, muscle, and whole blood of infected fish Bagarius bagarius (Hamilton) collected from different sites of the river Ganges. The percentage of the mean tail length of the comet was 10.28±0.36 in the reticulocytes of the infected fish which was significantly (P ?0.05) longer compared to the control (2.86±0.12). Similarly, a significantly (P ?0.05) higher DNA damage was observed in hepatocytes of parasite-infected fish (12.15±0.24) when compared to the control (3.024±0.013). A comparatively higher DNA damage was observed in the hepatocytes than the reticulocytes, indicative of tissue-specific DNA damage as hepatocytes are the biomarkers of metabolic functions prone toward biotic stress. A higher induction of MN was observed in infested fish (0.18±0.07) as compared to the control. Our results suggest that parasites contribute to the induction of cellular and DNA damage in fish during the progression of the host-parasite interaction.

Assessment of pollution of river Ganges by tannery effluents using genotoxicity biomarkers in murrel fish, Channa punctatus (Bloch).

River pollution due to rapid industrialization and anthropogenic activities adversely affects the aquatic organisms, especially fish. Here, we assessed the genotoxicity, mutagenicity and bioaccumulative aspects of tannery effluents in freshwater murrel, Channa punctatus, an inhabitant of river Gange. Test specimens were collected from three different polluted sites of the river within and nearby Kanpur area during different seasons and blood samples of these specimens were processed for comet assay and micronucleus test as genotoxicity biomarkers. A significantly (P <0.05) higher micronuclei induction, nuclear abnormalities and % tail DNA was observed in the specimens collected from the polluted sites. Bioaccumulation studies in the muscle (1.202 µg/g) and gill tissues (<0.300 µg/g) of the specimens revealed the concentration of chromium (core component of tanning industry) above the maximum permissible limits as prescribed by World Health Organization (WHO). The findings of the present analysis indicated contamination of river Ganges with tannery effluents which induce genotoxicity in fish with seasonal variation.