Cellular toxicity of surfactants used as herbicide additives

Abstract

The cellular toxicities of surfactants, a solvent, and an antifreeze that are included in herbicide formulations were assessed by measuring their effects on membrane integrity, metabolic activity, mitochondrial activity, and total protein synthesis rate in a cell culture. Polyethylene glycol, propylene glycol, and monoethylene glycol exhibited no cellular toxicity even at a high concentration of 100 mM. Sodium lauryl ether sulfate and polyoxyethylene lauryl ether significantly damaged the membrane, disturbed cellular metabolic activity, and decreased mitochondrial activity and the protein synthesis rate; however, their toxicity was far below those of the severely toxic chemicals at comparable concentrations. The severely toxic category included polyoxypropylene glycol block copolymer, polyoxyethylene tallow amine, and polyoxyethylene lauryl amine ether. These surfactants were cytotoxic between 3.125 µM and 100 µM in a dose-dependent manner. However, the toxicity graph of concentration vs toxicity had a point of inflection at 25 µM. The slope of the toxicity graph was gentle when the concentration was below 25 µM and steep when the concentration was greater than 25 µM. In conclusion, our results suggest that the toxicity of surfactants be taken care of pertinent treatment of acute herbicide intoxication.