Jožef Stefan International Postgraduate School, 1000 Ljubljana, Slovenia.
J Environ Radioact. 2013 Dec;126:147-55. doi: 10.1016/j.jenvrad.2013.07.019. Epub 2013 Sep 4.
An assessment of the radiological situation due to exposure to gamma radiation, radon ((222)Rn) and thoron ((220)Rn) was carried out at former uranium (U) mining and processing sites in Taboshar and at Digmai in Tajikistan. Gamma dose rate measurements were made using various field instruments. (222)Rn/(220)Rn measurements were carried out with field instruments for instantaneous measurements and then discriminative (222)Rn/(220)Rn solid state nuclear track detectors (SSNTD) were used for longer representative measurements. The detectors were exposed for an extended period of time in different outdoor and indoor public and residential environments at the selected U legacy sites. The results showed that gamma, (222)Rn and (220)Rn doses were in general low, which consequently implies a low to relatively low radiological risk. The radiation doses deriving from external radiation (gamma dose rate), indoor (222)Rn and (220)Rn with their short-lived progenies did not exceed national or international standards. At none of the sites investigated did the average individual annual effective doses exceed 10 mSv, the recommended threshold value for the general public. A radiation hazard could be associated with exceptional situations, such as elevated exposures to ionizing radiation at the Digmai tailings site and/or in industrial facilities, where gamma and (222)Rn/(220)Rn dose rates could reach values of several 10 mSv/a. Current doses of ionizing radiation do not represent a hazard to the health of the resident public, with the exception of some specific situations. These issues should be adequately addressed to further reduce needless exposure of the resident public to ionizing radiation.
在塔吉克斯坦的塔博沙尔和迪格迈，对前铀（U）矿和加工厂进行了因接触伽马辐射、氡（（222）Rn）和钍（（220）Rn）而导致的辐射情况评估。使用各种现场仪器进行了伽马剂量率测量。使用现场仪器进行了（222）Rn/（220）Rn 的即时测量，然后使用具有区分能力的（222）Rn/（220）Rn 固体核径迹探测器（SSNTD）进行更长时间的代表性测量。探测器在选定的 U 遗留场址的不同户外和室内公共和住宅环境中进行了长时间的暴露。结果表明，伽马、（222）Rn 和（220）Rn 剂量普遍较低，这意味着辐射风险较低或相对较低。来自外部辐射（伽马剂量率）、室内（222）Rn 和（220）Rn 及其短寿命产物的辐射剂量并未超过国家或国际标准。在所调查的任何一个地点，个体年平均有效剂量均未超过 10 mSv，这是普通公众的建议阈值。在迪格迈尾矿场和/或工业设施等特殊情况下，电离辐射的照射量可能会增加，此时的伽马和（222）Rn/（220）Rn 剂量率可能会达到数 10 mSv/a，与这种情况相关的辐射危害会超过上述推荐阈值。除了一些特殊情况，目前的电离辐射剂量不会对居住人群的健康构成危害。需要适当解决这些问题，以进一步减少居住人群不必要的电离辐射暴露。
