Ishikawa Y, Mori T, Kato Y, Machinami R, Priest N D, Kitagawa T
Department of Pathology, Cancer Institute, Tokyo, Japan.
Radiat Res. 1993 Aug;135(2):244-8.
It is well established that injected Thorotrast is deposited in the liver, spleen, bone marrow, and lymph nodes, but accumulations in organs with lower macrophage activity have previously been given little attention. In this work, neutron activation analysis has been used to investigate concentrations of thorium in autopsy samples taken at sites of major and minor deposition in 24 Thorotrast patients. In the latter category, the highest values were found in the testis [40 x 10(-6) g/g(wet)], followed by those in the adrenal gland, gallbladder, lung, and pancreas. The resulting alpha-particle dose rates (mGy/year) are tentatively estimated to be 8.5 to the testis, 5.5 to the gallbladder, and 5.3 to the lung. These results may be relevant to the residual excess mortality among Thorotrast patients after diseases of the principal organs of deposition have been excluded; they also support previous indications that thorium deposited in pulmonary tissues is responsible for an important component of the total dose to the lung. In another context, our data may bear on the connection, postulated elsewhere, between exposure to alpha-particle emitters and elevated incidence of leukemia in the children of workers engaged in the reprocessing of nuclear fuel.
众所周知，注入的钍造影剂会沉积在肝脏、脾脏、骨髓和淋巴结中，但此前很少有人关注巨噬细胞活性较低的器官中的积累情况。在这项研究中，中子活化分析被用于调查24名钍造影剂患者主要和次要沉积部位尸检样本中的钍浓度。在后者中，睾丸中的钍浓度最高[40×10(-6)克/克（湿重）]，其次是肾上腺、胆囊、肺和胰腺。初步估计，由此产生的α粒子剂量率（毫戈瑞/年）分别为：睾丸8.5、胆囊5.5、肺5.3。这些结果可能与排除主要沉积器官疾病后钍造影剂患者中剩余的额外死亡率有关；它们还支持了先前的观点，即沉积在肺组织中的钍是肺部总剂量的重要组成部分。在另一种情况下，我们的数据可能与其他地方假设的α粒子发射体暴露与从事核燃料后处理的工人子女白血病发病率升高之间的联系有关。
