[Neutral and zwitterionic detergents: dependence of biological effectiveness on critical micellar concentration]

The biological activity of various zwitterionic and nonionic detergents was studied as a function of the corresponding critical micellar concentration (CMC-values). The criteria chosen to measure biological activities were inhibition of bioluminescence, lysis and cell-killing of Vibrio fischeri, hemolysis, and inhibition of Daphnia magna. When Zwittergent-detergents were studied in three different bioassays their biological activity increased with decreasing CMC-values. However, the biological activity of various TWEEN-detergents and alkylglucopyranosides depended on CMC-values in a very different way. We therefore conclude that CMC-values, length of alkylgroups and charge are parameters not yet sufficient to predict the potential toxicity of detergents.