Lack of genotoxicity of the herbicide atrazine in cultured human lymphocytes.

The widely used herbicide atrazine was evaluated for genotoxicity in cultured human peripheral blood lymphocytes. Sister-chromatid exchanges (SCE), chromosome aberrations (CA) and micronuclei (MN) were scored as genetic endpoints. To detect eventual metabolic modification in the genotoxicity of this herbicide, the cultures of SCE and MN demonstration were also treated with S9 microsomal fraction. From our results we can conclude that atrazine was able to exert a weak cytotoxic effect. However, the overall evaluation of the genotoxicity data indicate that this herbicide is not effective in the three assays conducted, irrespective of the presence of metabolic activation, which would mean a general lack of effectiveness of atrazine to induce clastogenic and aneugenic damage in cultured human lymphocytes.