Genotoxicity of the herbicide formulation Roundup® (glyphosate) in Caiman latirostris evidenced by the Comet assay and the Micronucleus test

POLETTA, G.; A. LARRIERA; E. KLEINSORGE AND M.D. MUDRY.

Santa Cruz de la Sierra, Bolivia

Congreso; 19th Working Meeting of the Crocodile Specialist Group, IUCN-SSC; 2008

CSG/IUCN/SSC

The genotoxicity of pesticides is an issue of worldwide concern. Any damage induced in essential portions of the DNA can become particularly pronounced when the lesions are produced during embryogenesis, when rapid organogenesis is taking place. The present study was undertaken to evaluate the genotoxic potential of a widely used herbicide formulation, Roundup® (glyphosate), in erythrocytes of broad-snoated caiman after in ovo exposure. Caiman embryos were exposed at early embryonic stage to different sub-lethal concentrations of Roundup® (50, 100, 200, 300, 400, 500, 750, 1000, 1250 and 1750 µg/egg). At time of hatching, blood samples were obtained from each animal and two short-term tests, the Comet assay (CA) and the Micronucleus (MN) test, were performed on erythrocytes to assess DNA damage. A significant increase in DNA damage was observed, at concentration of 200 µg/egg or higher, compared to untreated control eggs (p < 0.05). Results from the CA revealed a dose-dependent effect. This study demonstrated adverse effects of Roundup® on DNA of C. latirostris and confirmed that the comet assay and the MN test applied on caiman erythrocytes are useful tools in determining potential genotoxicity of chemical agents.