Objective: Nasal mucosa toxicity of cremophor RH40 and labrafil M 1944 CS were investigated

in order to explore feasibility of their application in nasal drug delivery system. Method: Compared with span-80 and tween-80

safety of surfactant was evaluated by testing cilia movement of in situ toad palate model and hemolysis test of erythrocyte membrane in rabbits. Result: When concentrations of these four kinds of surfactants were 1%

their effect on cilia movement was in order of cremophor RH40 < labrafil M 1944 CS < tween-80 < span-80. By survey of toxic effects on cell membranes

cremophor RH40 had little cell membrane toxicity

tween-80 and span-80 had moderate cell membrane toxicity

but labrafil M 1944 CS had serious cell membrane toxicity.Dosage of cremophor RH40 that had no effect on integrity of cell membrane was 15 times the amount of tween-80 and span-80. Conclusion: Cremophor RH40 has little toxic effect on nasal mucosa under a certain range of concentration that can be applied in nasal drug delivery system.