Zhukovsky M, Vasyanovich M, Onishchenko A, Vasilyev A
Institute of Industrial Ecology UB RAS, Ekaterinburg, Russia.
Institute of Industrial Ecology UB RAS, Ekaterinburg, Russia.
Appl Radiat Isot. 2019 Sep;151:1-6. doi: 10.1016/j.apradiso.2019.05.035. Epub 2019 May 25.
High levels of the unattached Pb fraction of the Rn decay products in the atmosphere of the monazite storage facility were found: f = 0.3-0.5 at the aerosol concentration of 20 000 cm and 0.1-0.16 at aerosol concentration ∼140 000 cm. It is shown that the sampling of aerosols in an atmosphere with a high concentration of thoron result in the local change of the equilibrium between the attached and unattached fractions near the sampling point. As a result, the measured value of the unattached fraction of thoron decay products may differ by several orders of magnitude from the mean value of unattached fraction the in the indoor atmosphere. A local increase of the unattached fraction Pb can take place in the worker's breathing zone in the atmosphere with a high concentration of thoron and it should be taken into account in the assessment of the inhalation intake of the thoron decay products for workers.
在独居石储存设施的大气中发现，氡衰变产物的游离铅部分含量很高：在气溶胶浓度为20000/cm³时，f = 0.3 - 0.5；在气溶胶浓度约为140000/cm³时，f = 0.1 - 0.16。结果表明，在钍射气浓度较高的大气中采集气溶胶，会导致采样点附近附着部分和游离部分之间的平衡发生局部变化。因此，钍衰变产物游离部分的测量值可能与室内大气中游离部分的平均值相差几个数量级。在钍射气浓度较高的大气中，工人呼吸区内的游离铅部分可能会局部增加，在评估工人吸入钍衰变产物的摄入量时应予以考虑。
