Estimation of Dose-Rate Effectiveness Factor for Malignant Tumor Mortality: Joint Analysis of Mouse Data Exposed to Chronic and Acute Radiation
Estimation of Dose-Rate Effectiveness Factor for Malignant Tumor Mortality: Joint Analysis of Mouse Data Exposed to Chronic and Acute Radiation
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DOI：
10.1667/rade-19-00003.1
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发表时间：
2020-11-01
影响因子：
3.4
通讯作者：
Kakinuma, Shizuko
中科院分区：
文献类型：
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作者：
Doi, Kazutaka;Kai, Michiaki;Kakinuma, Shizuko
流行病学研究中由于混杂因素造成的不确定性限制了我们对低剂量率慢性暴露对人体健康影响的了解。动物实验，其中每个受试者被认为几乎相同，可以补充流行病学研究的局限性。因此，我们对先前发表的Cs-137 γ射线慢性和急性照射B6C3F1雌性小鼠的癌症死亡率数据进行了联合分析，以估计剂量率有效因子。在环境科学研究所进行的慢性辐照动物实验中，小鼠从8周龄开始连续400天每天接受0.05、1.1或21毫戈瑞剂量率的辐照。在国家放射科学研究所进行的急性辐照动物实验中，小鼠在35、105、240或365日龄时接受1.9、3.8或5.9 Gy的辐射，剂量率为0.98 Gy / min。由于初步分析表明，风险取决于暴露时的年龄，因此应用了一个模型，该模型考虑了取决于这一因素的风险差异。模型分析显示，与急性辐射小鼠相比，每天暴露于21毫戈瑞的小鼠每戈瑞的风险显著降低了三倍。这导致了比以前报道的更大的剂量率有效性因子。(C)辐射研究学会2020
Uncertainties due to confounding factors in epidemiological studies have limited our knowledge of the effects of low-dose-rate chronic exposure on human health. Animal experiments, wherein each subject is considered to be nearly identical, can complement the limitations of epidemiological studies. Therefore, we conducted a joint analysis of previously published cancer mortality data in B6C3F1 female mice chronically and acutely irradiated with Cs-137 gamma rays to estimate the dose-rate effectiveness factor. In the chronically irradiated animal experiment conducted by the Institute for Environmental Sciences, mice received irradiation at dose rates of 0.05, 1.1 or 21 mGy per day for 400 days from 8 weeks of age. For the acutely irradiated animal experiment conducted by the National Institute of Radiological Sciences, mice received irradiation at 35, 105, 240 or 365 days of age with 1.9, 3.8 or 5.9 Gy at a dose rate of 0.98 Gy per min. Because the preliminary analyses suggested that the risk was dependent on the age at exposure, a model was applied that considered risk differences depending on this factor. The model analysis revealed a three-fold, significantly decreased risk per Gy in mice exposed to 21 mGy per day compared to that in acutely irradiated mice. This resulted in a dose-rate effectiveness factor larger than that reported previously. (C) 2020 by Radiation Research Society