In Vitro Cytotoxic Effect of Glyphosate Mixture Containing Surfactants

We investigated whether glyphosate influences the cellular toxicity of the surfactants TN-20 and LN-10 on the mouse fibroblast-like cells, alveolar epithelial cells, and a heart cell line. The cytotoxicity of TN-20 and LN-10 (0.4-100 mu M), in the presence or absence of glyphosate was determined by assessing membrane integrity. TN-20 toxicity was significantly lower in the presence of 50 mu M glyphosate for the fibroblast-like cell (6.25 mu M; 3.9% +/- 3.4% vs -4.8% +/- 0.7%), for the alveolar cells (0.78 mu M; 5.7% +/- 0.9% vs 0.1% +/- 0.6%), and for the heart cell line (25.0 mu M; 7.9% +/- 3.0% vs 19.4% +/- 0.7%) compared to that of TN-20 alone. The cellular toxicity of LN-10 towards the fibroblast-like cells was found to be increased in the presence of 50 mu M glyphosate when LN-10 concentrations of 50 mu M (31.3% +/- 3.9% vs 19.2% +/- 0.9%) and 100 mu M (62.1% +/- 3.4% vs 39.0% +/- 0.7%) were compared to that of LN-10 alone. These results suggest that the mixture toxicity may be a factor in glyphosate-surfactant toxicity in patients with acute glyphosate herbicide intoxication.