Nuclear Physics Laboratory. Faculty of Science. University of Yaoundé I. P.O. Box 812 Yaoundé. Cameroon.
J Radiat Res. 2021 Mar 10;62(2):226-235. doi: 10.1093/jrr/rraa140.
During prostate cancer treatment with 223Ra. 219Rn (actinon) occurs and may be exhaled by the patient. Nurses and other hospital employees may inhale this radionuclide and its decay products. The alpha-emitting decay products of actinon deposited within a body will irradiate tissues and organs. Therefore. it is necessary to evaluate organ doses of actinon progeny. The purpose of this study is to set up a dosimetric method to assess dose coefficients for actinon progeny. The effective dose coefficients were calculated separately for three modes. The unattached mode which concerned the activity median thermodynamic diameter (AMTD) of 1 nm. and the nucleation and accumulation modes which are represented by activity median aerodynamic diameters (AMAD) of 60 and 500 nm respectively. The recent biokinetic models of actinon progeny developed in the Occupational Intakes of Radionuclides (OIR) publications series of the International Commission of Radiological Protection (ICRP) were implemented on BIOKMOD (Biokinetic Modeling) to calculate the number of nuclear transformations per activity intake of actinon progeny. The organ equivalent and effective dose coefficients were determined using the dosimetric approach of the ICRP. The inhalation dose coefficients of actinon progeny are dominated by the contribution of lung dose. The calculated dose coefficients of 211Pb and 211Bi are 5.78 × 10-8 and 4.84 × 10-9 Sv.Bq-1 for unattached particles (AMTD = 1 nm). and 1.4 × 10-8 and 3.55 × 10-9 Sv.Bq-1 for attached particles (AMAD = 60 nm). and 7.37 × 10-9 and 1.91 × 10-9 Sv.Bq-1 for attached particles (AMAD = 500 nm). These values are much closer to those of the recently published ICRP 137.
在使用 223Ra 治疗前列腺癌期间，会产生 219Rn（锕射气），患者可能会将其呼出。护士和其他医院员工可能会吸入这种放射性核素及其衰变产物。锕射气在体内沉积的α发射衰变产物会辐射组织和器官。因此，有必要评估锕射气后代的器官剂量。本研究的目的是建立一种剂量学方法来评估锕射气后代的剂量系数。分别为三种模式计算有效剂量系数。非附着模式关注的是 1nm 的活动中值热力学直径（AMTD），成核和积累模式分别代表 60nm 和 500nm 的活动中值空气动力学直径（AMAD）。国际放射防护委员会（ICRP）职业放射性核素摄入量（OIR）系列出版物中最近开发的锕射气后代生物动力学模型已在 BIOKMOD（生物动力学建模）上实施，以计算每单位锕射气后代摄入量的核转化数。器官当量和有效剂量系数是使用 ICRP 的剂量学方法确定的。锕射气后代的吸入剂量系数主要由肺剂量贡献决定。未附着粒子（AMTD=1nm）的 211Pb 和 211Bi 计算剂量系数分别为 5.78×10-8和 4.84×10-9Sv.Bq-1，附着粒子（AMAD=60nm）分别为 1.4×10-8和 3.55×10-9Sv.Bq-1，附着粒子（AMAD=500nm）分别为 7.37×10-9和 1.91×10-9Sv.Bq-1。这些值与最近发表的 ICRP 137 更接近。
