Miller G, Guilmette R, Bertelli L, Waters T, Romanov S A, Zaytseva Y V
Los Alamos National Laboratory, Los Alamos, NM, USA.
Radiat Prot Dosimetry. 2008;131(3):316-30. doi: 10.1093/rpd/ncn181. Epub 2008 Aug 8.
This study makes use of 63 cases of Mayak workers exposed to Pu-239 with autopsy data and some late-time urine bioassay data. In addition, air-concentration data--used to construct monthly average values--are available for each case, which provide the time dependence and potential magnitudes of normal inhalation intakes for each case. The purpose of the study is to develop and test Bayesian methods of dose calculation for the Mayak workers. The first part of the study was to quantitatively characterise the uncertainties of the bioassay data. Then, starting with three different published biokinetic models, the data are fit by varying intake and model perturbation parameters, e.g., parameters influencing the lung, thoracic lymph nodes, liver and bone retention. Statistical self-consistency arguments are used to check the measurement uncertainty parameters within the Poisson-lognormal model. The second part of the study is to set up and test Bayesian dose calculations, which use the point determinations of biokinetic parameters from the study cases within a discrete, empirical Bayes approximation. The main conclusion of the study is that these methods are now ready to be applied to the entire Mayak worker population.
本研究利用了63例接触钚-239的玛雅克工人的尸检数据以及一些后期的尿液生物测定数据。此外，可获取用于构建月平均值的空气浓度数据，这些数据针对每个案例提供了正常吸入摄入量的时间依赖性和潜在量级。该研究的目的是开发并测试针对玛雅克工人的贝叶斯剂量计算方法。研究的第一部分是定量表征生物测定数据的不确定性。然后，从三个不同的已发表生物动力学模型开始，通过改变摄入量和模型扰动参数（例如影响肺部、胸段淋巴结、肝脏和骨骼滞留的参数）来拟合数据。使用统计自洽性论据来检验泊松对数正态模型内的测量不确定度参数。研究的第二部分是建立并测试贝叶斯剂量计算，其在离散的经验贝叶斯近似内使用来自研究案例的生物动力学参数的点测定值。该研究的主要结论是，这些方法现在已准备好应用于整个玛雅克工人群体。
