Objective: To observe the actute toxicity of volatile oil from Bupleurum chinense in mice and rats and evaluate its safety. Method: Ig volatile oil from B. chinense of different dosages to mice and rats; the acute toxical symptoms

signs

death time and accumulated death rate were observed and the LD50 was calculated by Bliss method. Result: Restlessness

abnormal walking

accelerated heart rate

breathlessness

consecutive convulsion were the main acute toxical symptoms and signs caused by volatile oil from B. chinense ;the LD50 and its 95% confident limit of volatile oil of B. chinense to rats and mice are 2.081(1.759 9-2.461 3)mL·kg-1 and 3.118(2.872 4-3.391 2)mL·kg-1 differently. Conclusion: Ig volatile oil from B. chinense to rats and mice can cause acute toxical injury to them.The further study on toxical components

toxical cheminisms and toxical targets of volatile oil from B. chinense are need to do

so as to offer experimental basement for the safe and effective application of B. chinense and its preparation.