GENOTOXIC EFFECTS OF EXPOSURE TO VERY LOW CONCENTRATIONS OF THE GLYPHOSATE-BASED HERBICIDE, “ROUNDUP” ON THE GILLS, GONADS AND LIVER OF JUVENILE CLARIAS GARIENPINUS

ABSTRACT

Glyphosate is the most popular herbicide used in the world today and has increased in usage as weed resistance developed. Due to its effectiveness and affordability, “Roundup”, a commercialized formulation of glyphosate, is today the second most widely used herbicide in urban areas and in agriculture. The increased use of glyphosate and glyphosate-based herbicides has led to adverse toxic effects on the environment, animals, and humans even at low concentrations. In this study, we assessed the genotoxic effects of very low concentrations of the glyphosate-based herbicide (“Roundup”), on the gills, gonads, and liver of juvenile Clarias gariepinus. The different concentrations of “Roundup” used in this study were 0.03 mL/L, 0.06 ml/L, 0.10 mL/L and 0.13 mL/L respectively. The acute toxicity study carried out revealed mortality in some of the treated groups especially in the group administered with the highest concentration of “Roundup” where one hundred percent (100%) mortality was observed after 96 hours. Behavioural changes such as erratic movements, bringing bubbles from their mouths, discoloration, restlessness, and gasping for air was also observed in the various “Roundup” concentrations. Probit analysis carried out revealed that the LC50 of “Roundup”, for this study was 0.04ml/L. Genotoxicity assessment using the comet assay revealed significant (p<0.001) damage to the genetic material (DNA) in the gills, gonads and liver of juvenile Clarias gariepinus when treatments were compared with control. The findings from this study indicated that even at very low concentrations, significant genotoxic damages were seen in the gills, gonads and liver of clarias garienpinus.