百草枯对小鼠的急性毒性试验

The acute toxicity of Paraquat in mice

目的 观察百草枯（Paraquat，PQ）对小鼠的急性毒性，计算其半数致死量（LD50）。方法 给小鼠灌服不同浓度的PQ溶液，通过观察小鼠的活动和毒性反应，记录小鼠的死亡数，用概率单位法计算LD50。结果 给药后不同时间内，小鼠出现自由活动减少，濒死时呼吸频率加快、张口呼吸、鼻翼扇动等中毒症状，死亡高峰在2h内，死亡原因为多脏器损伤。6小鼠LD50=106．99mg·kg^-1，95％可信限范围为97．01～118．03mg·kg^-1早小鼠LD50=86．40mg·kg^-1，95％可信限范围74．54～100．14mg·kg^-1。结论 PQ属于中等毒农药，早小鼠更敏感。

OBJECTIVE To explore the acute toxicity of Paraquat（PQ） in mice and calculate its 50% lethal dose （ LD50 ）. METHODS Different doses of PQ were orally given to mice. The movement and the toxic symptoms were observed, and the number of death of mice was recorded. The LD50 was calculated with probability units method. RESULTS The times of movement of mice were reduced after PQ was given. Before death, the respiratory rate of mice increased, accompanied with gasping breath and flapping of masal alae. The death peak time was within 2 h and the cause of death was multiple organ failure syndrome （MOFS）. The values of PQ LD50 in male and female mice were 106.99 mg·kg ^-1 （ 97.01 - 118.03 mg·kg ^-1 ） and 86.40 mg·kg^-1 （ 74.54 - 100. 14 mg·kg ^-1）, respectively. CONCLUSION PQ is a pesticide with moderate toxicity. The female mice are more sensitive to the toxicity of PQ.