Comparison of cytotoxicity of various surfactants tested on normal human fibroblast cultures using the neutral red test, MTT assay and LDH release.

We used the neutral red test, MTT assay and lactate dehydrogenase (LDH) release to compare the potential cytotoxicity of six surfactants belonging to different classes--three non-ionic surfactants (Triton x100, octylphenoxypolyethoxy alcohol, from Orion; Tween 60, polyoxyethylene (20) sorbitan monostearate, from ICI Speciality Chemicals; Tween 80, polyoxyethylene (20) sorbitan monolaurate, from Labosi), two anionic surfactants (Texapon K1298, sodium lauryl sulphate, from Henkel; Texapon N40, sodium laurylether sulphate, from Henkel) and one cationic surfactant (benzethonium chloride, from Siber Hegner)--on human fibroblast cultures. According to the LC50 (microg ml(-1)), the tested surfactants can be classified in the following order of increasing cytotoxicity: Tween 80 < Texapon N40 < Tween 60 < Texapon K1298 < Triton x100 < benzethonium chloride.