Study And Evaluationof Environmental Radioactivity Level In Baotou City

With the acceleration of the process of modern industry development,more and moreenvironmental problems have become increasingly apparent.People not only care about thetraditional environmental problems,such as water,air,soil,solid waste and other,but alsonatural radioactivity begin entering the field of vision of ordinary people.As a newindustrial city,the existing resident population of Baotou is more than2million,having thecountry top associated rare earth-Bayan Obo ore.This Topic is to explicit wheth the processof using rare earth mine will cause the increase of urban natural radioactive and providedata support for is the area of the study of radioactivity and radiation protection workprovide.The survey which combining the situ measuring instruments and laboratory sampleanalysis is to measure the living radioactive environment of Baotou city,monitor andanalysis of district which engaged in radioactive production activities.According to the results of the survey,the Baotou city instantaneous gamma radiationair absorbed dose rate mean value is62.5nGy/h,which is close to the numerical value of airborne gamma of Baotou in2006and the published national average level.This value isstable in contrast to years of previous data.In the past few years,the irradiation of theBaotou city has not changed significantly,so the external irradiation environment is safeand reliable.The radioactive detection of aerosol and sediment is in the range of lowlimit.We have test radionuclides and total α and total β of Surface water and drinking waterat the same time,the result conformed meet to the standard.So we may easily draw aconclusion that water radioactive environment of Baotou City will not caused badinfluence on the daily life of the public.The estimation results of effective dose of external irradiation show that the effectivedose of adult in Baotou was0.58mSv,which is Slightly higher than the national averageand the world average of the Inner Mongolia Autonomous Region. The internal irradiationestimation of the Radon, Thorium gas and its progeny induced the effective adult dose was1.87mSv. It is higher than the national average and the world average.The results of theestimation vaule is high.It is probably because the concentration of indoor Radon, Thorium gas and its progeny are high.In addition,the contribution of Thorium gas and its progeny ofBaotou city to internal irradiation account for48%for overall, far higher than the nationallevel of25%,and is6times of the world level8%.The contents of the Thorium gas and itsprogeny is obviously higher than other regions,which belongs to the characteristicpollutant.From the above results,it can be concluded that the public annual effective dose ofBaotou city is higher than the world average,and it is equivalent to the average level of ourcountry.The natural radioactive environment of Baotou city is safe and reliable,and do notcaused bad influence on the daily life of the public.Radioactive environment of BaotouSteel and blast furnace slag dam results is significantly higher than that in urban areas ofBaotou city environment,which indicating that the using process of associated mineral mayresulting in increase of environmental radioactivity in only small scope of the productionarea,but not produce significantly affect of Baotou city radioactive environment.