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目的 调查滇西某退役铀矿周边环境的放射性水平,评估其对居民产生的健康风险;方法 通过对退役铀矿周边环境的土壤、农作物、水体样品的采集、制备和高纯锗γ能谱仪分析,给出环境介质中的放射性核素含量;结果 土壤中238U、232Th、226Ra、40K和137Cs的比活度均值分别为83.0、85.4、71.4、524和1.27 Bq/kg;鲜茶叶中238U、232Th、226Ra、40K和137Cs的比活度均值分别为0.061、0.652、0.650、92.5和0.061Bq/kg;玉米中238U、232Th、226Ra、40K和137Cs的比活度均值分别为0.184、0.122、0.302、78.3和0.015 Bq/kg;大白菜中238U、232Th、226Ra、40K和137Cs的比活度均值分别为0.090、0.224、0.469、80.0和0.011 Bq/kg;饮用水中232Th、226Ra和40K的比活度均值分别为0.146、0.310和2.25 Bq/L,238U和137Cs的比活度低于探测下限.土壤中天然放射性核素所致居民人均外照射年有效剂量为131μSv/年;结论 退役铀矿周边环境放射性水平在正常本底范围,对居民造成的健康风险较低.“,”Objective To investigate radioactivity level in the surrounding environment ofadecommissioned uranium mine in western yunnan, and evaluate health risks to residents.Methods The crops, soil andwater samples were collectedand analyzed using HPGe gamma ray spectrometer, to get the radionuclide contents in the environmental medium.Results In the samples, the mean specific activitiesl of 238U、232Th、226Ra、40Kand 137Csin soil were83.0, 85.4, 71.4, 524 and 1.27 Bq/kg, respectively;the mean specific activities of 238U, 232Th, 226Ra, 40K and 137Csin fresh tea leaves were 0.061, 0.652, 0.650, 92.5 and 0.061 Bq/kg, respectively;the mean specific activities of 238U、232Th、226Ra、40K and 137Csin maizewere0.184, 0.122, 0.302, 78.3 and 0.015 Bq/kg, respectively; Radioactivity levels of 238U、232Th、226Ra、40K and 137Csin cabbages were 0.090, 0.224, 0.469, 80.0 and 0.011 Bq/kg, respectively;the mean specific activities of 232Th, 226Ra and 40K in drinking water were 0.146, 0.310 and 2.25 Bq/L, respectively, and the specific activities of the 238U and 137Cs in drinking water were lower than the detection lower limit respectively. The average annual effective doseof natural radionuclides in soil was 131 μSv per year. Conclusion The level of radioactivity in the environment around decommissioned uranium mines is within the normal background, which poses low health risks to the residents.