Tritium Research Center, Institute for Environmental Sciences, Rokkasho-Mura, Aomori-Ken, Japan.
Nuclear Science and Engineering Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki-ken, Japan.
J Radiol Prot. 2024 Sep 23;44(3). doi: 10.1088/1361-6498/ad7a04.
In 2016, the International Commission on Radiological Protection (ICRP) has revised the biokinetic models for carbon and tritium in Publication 134 to calculate the dose coefficients of these radionuclides for workers. The following publication for members of the public is now in the process of revising by the ICRP. According to the draft manuscript published for consultation in 2023, the same models will be adopted for members of the public, although the parameters in these models are not corroborated by the metabolic data of radionuclides in foods. Dose coefficients for adult were estimated using modified models developed in this study to validate the application of the revised ICRP models to members of the public. In the modified models, several parameters were replaced based on the metabolic data of these nuclides in foods and compartments of radio-insensitive tissues were introduced. For these estimations, we utilised an inhouse program for internal-dose calculation developed by the Japan Atomic Energy Agency. The estimated dose coefficient values for ingestion of organicC and organically bound tritium (OBT) ranged from 3.2 × 10-7.6 × 10Sv Bqand from 3.5 × 10-5.4 × 10Sv Bq, respectively. We concluded that the dose coefficient value of 1.6 × 10Sv Bqobtained by the revised ICRP's carbon model was conservative for members of the public, while the value of 5.1 × 10Sv Bqfor OBT was appropriate.
2016 年,国际辐射防护委员会(ICRP)在出版物 134 中修订了碳和氚的生物动力学模型,以计算这些放射性核素的工作人员剂量系数。目前,ICRP 正在修订针对公众的相关出版物。根据 2023 年公布的征求意见草案,同样的模型将适用于公众,尽管这些模型中的参数未经食物中放射性核素的代谢数据证实。本研究采用修正模型对成人剂量系数进行了估算,以验证修订后的 ICRP 模型在公众中的应用。在修正模型中,根据食物中这些核素的代谢数据和对放射性不敏感组织的隔室替换了几个参数。对于这些估算,我们使用了由日本原子能机构开发的内部剂量计算内部程序。摄入有机碳和有机结合氚(OBT)的估计剂量系数值分别为 3.2×10-7 至 6.0×10-7Sv Bq 和 3.5×10-5 至 5.4×10-5Sv Bq。我们得出结论,修订后的 ICRP 碳模型的 1.6×10Sv Bq 剂量系数值对公众是保守的,而 OBT 的 5.1×10Sv Bq 值是合适的。