Abstract: BACKGROUND AND AIM: To study the estrogenic effects of common used organophosphrus pesticides, by the observation of the height of endometrium epidemic cells and the height of endometrium stroma cells of immature mice uterus treated with rganophosphrus pesticides. MATERIAL AND METHODS: Six kinds of organophosphrus pesticides dimethoate 19 mg/kg, acephate 47 mg/kg, paraoxon 0.056 mg/kg, malation 87 mg/kg, parathion 0.4 mg/kg and moncrotophos 3.54 mg/kg were given intraperitoneal for 3 days consecutively to mice respectively. All mice were sacrificed after three days, then the uterus wet weight, the ratio of uterus to body weight , the height of endometrium epidemic cells and the height of endometrium stroma cells were measured. RESULTS: All these six organophosphrus pesticides couldn't proliferate the immature mice' uterus wet weight and the ratio of uterus to body weight, but dimethoate and malation could induce increment of the height of endometrium epidemic cells and the height of endometrium stroma cells,compared with the control group(P<0.05). CONCLUSION: Dimethoate and malation maybe have the potential estrogenicity.

Key words: organophosphrus pesticides, uterotrophic assay, uterus endometrium epidemic cells, uterus endometrium stroma cells