Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
Radiat Res. 2010 Oct;174(4):496-516. doi: 10.1667/RR2243.1.
This paper summarizes the biokinetic database for iodine in the human body and proposes a biokinetic model for systemic iodine for use in dose assessments for internally deposited radioiodine. The model consolidates and extends existing physiological systems models describing three subsystems of the iodine cycle in the body: circulating inorganic iodide, thyroidal iodine (trapping and organic binding of iodide and synthesis, storage and secretion of thyroid hormones), and extrathyroidal organic iodine. Thyroidal uptake of inorganic iodide is described as a function of stable iodine intake (Y, µg day(-1)) and thyroidal secretion of hormonal iodine (S, µg day(-1)). Baseline parameter values are developed for reference adults with typical iodine intake. Compared with the current systemic biokinetic model of the International Commission on Radiological Protection (ICRP) for occupational intake of radioiodine, the proposed model predicts higher absorbed doses to the thyroid per unit uptake to blood for very short-lived iodine isotopes, similar absorbed doses to thyroid for iodine isotopes with half-life of at least a few hours, and substantially higher estimates of absorbed dose to stomach wall, salivary gland and kidneys for most iodine isotopes. Absorbed dose estimates for intravenous administration of radioiodine-labeled thyroid hormones based on the proposed model differ substantially in some cases from current ICRP values.
本文总结了人体碘的生物动力学数据库，并提出了一个用于评估内照射放射性碘的全身碘生物动力学模型。该模型整合和扩展了现有的描述体内碘循环三个子系统的生理系统模型：循环无机碘、甲状腺碘（碘的捕获和有机结合以及甲状腺激素的合成、储存和分泌）和甲状腺外有机碘。无机碘的甲状腺摄取被描述为稳定碘摄入量（Y，µg/天）和甲状腺激素碘分泌（S，µg/天）的函数。为具有典型碘摄入量的参考成年人制定了基线参数值。与国际放射防护委员会（ICRP）目前用于职业性摄入放射性碘的全身生物动力学模型相比，所提出的模型预测对于极短寿命碘同位素，每单位摄取到血液中的甲状腺吸收剂量更高，对于半衰期至少几个小时的碘同位素，甲状腺吸收剂量相似，对于大多数碘同位素，胃壁、唾液腺和肾脏的吸收剂量估计值要高得多。基于所提出的模型，静脉内给予放射性碘标记的甲状腺激素的吸收剂量估计值在某些情况下与当前的 ICRP 值有很大差异。
