Fig. 3.

Comparison of toxicity with respect to membrane integrity (A), metabolic activity (B), mitochondrial activity (C), and total protein synthesis rate (D). Note that PEG 300 (an antifreeze), PG, and MEG (solvents) exhibited no toxicity even at a high concentration of 100 mM. Three out of 4 nonionic surfactants (PE-61, TN-20, and LN-10) exhibited severe toxicity in a similar dose-dependent manner between 3.125 µM and 100 mM. The toxicity graph derived from the concentrations of PE-61, TN-20, and LN-10 has a point of inflection at 25 µM. The slope increases slowly up to 25 µM and decreases rapidly thereafter.