Genotoxicity of glyphosate assessed by the comet assay and cytogenetic tests

It was evaluated the genotoxicity of glyphosate which up to now has heterogeneous results. The comet assay was performed in Hep-2 cells. The level of DNA damage in the control group (5.42 +/- 1.83 arbitrary units) for tail moment (TM) measurements has shown a significant increase (p < 0.01) with glyphosate at a range concentration from 3.00 to 7.50 mM. In the chromosome aberrations (CA) test in human lymphocytes the herbicide (0.20-6.00 mM) showed no significant effects in comparison with the control group. In vivo, the micronucleus test (MNT) was evaluated in mice at three doses rendering statistical significant increases at 400 mg/kg (13.0 +/- 3.08 micronucleated erythrocytes/ 1000 cells, p < 0.01). In the present study glyphosate was genotoxic in the comet assay in Hep-2 cells and in the MNT test at 400 mg/kg in mice. Thiobarbituric acid reactive substances (TBARs) levels, superoxide dismutase (SOD) and catalase (CAT) activities were quantified in their organs. The results showed an increase in these enzyme activities. (C) 2009 Elsevier B.V. All rights reserved.