陈 飞 尹亮亮 孔祥银 邵宪章 申宝鸣 吉艳琴（中国疾病预防控制中心辐射防护与核安全医学所 辐射防护与核应急中国疾病预防控制中心重点实验室 北京 100088）



生物样品中锶-90分析的不确定度评定

陈 飞 尹亮亮 孔祥银 邵宪章 申宝鸣 吉艳琴
（中国疾病预防控制中心辐射防护与核安全医学所 辐射防护与核应急中国疾病预防控制中心重点实验室 北京 100088）

摘要以茶叶样品锶-90分析为例，详细介绍了生物样品中锶-90分析不确定度的来源，数学模型的建立，标准不确定度的合成，不确定度分量以及扩展不确定度的计算。深入讨论了各不确定度分量对总不确定度的贡献。结果显示：该茶叶样品锶-90活度的分析结果为(68.8±2.6) Bq/kg，该样品的不确定度主要来自β计数的测量、仪器探测效率和样品化学回收率。

关键词锶-90，不确定度，生物样品，萃取色层法

Supported by the Basic Work Project of Chinese Ministry of Science and Technology (No. 2014FY211000)

First author: CHEN Fei, male, was born in January 1983 and graduated with a doctor’s degree from Institute of High Energy Physics (CAS) in July 2014. Now he is an assistant researcher engaging in the analysis of radiation chemistry

Received 22 September 2015, accepted 04 December 2015

Uncertainty evaluation of strontium-90 analysis in biological samples

CHEN Fei YIN Liangliang KONG Xiangyin SHAO Xianzhang SHEN Baoming JI Yanqin
(China CDC Key Laboratory of Radiological Protection and Nuclear Emergency, National Institute for Radiological Protection, China CDC, Beijing 100088, China)

ABSTRACT In order to completely express the results of Sr-90 analysis, this paper presents the uncertainty evaluation of Sr-90 analysis in biological samples. Determination of Sr-90 in tea ash was taken as an example, the origins of uncertainty were discussed in detail and the mathematical model was established. Uncertainty components, standard uncertainty and expanded uncertainty were respectively calculated as well. Contributions of uncertainty components were also compared. The results showed that the radioactivity of Sr-90 in the tea ash was (68.8±2.6) Bq/kg (k=2), and the uncertainty mainly originated from Y-90 beta-counting, detection efficiency of equipment and chemical recovery of the method.

KEYWORDS Sr-90, Uncertainty, Biological samples, Extraction chromatography

CLC TL84

锶-90是核监测活动中备受关注的信号核素。切尔诺贝利核事故后，高毒性锶-90被认为是影响健康评价的主要放射性核素之一[1]，也是日本福岛核事故后对环境、食品饮用水等样品监测的主要核素[2-3]。我国现行有效的生物、食品和水样品中锶-90的分析方法标准均制定于80年代末到90年代初[4]，结果表示均未涉及不确定度。根据国际标准化组织定义，不确定度是表征合理地赋予被测量值的分散性、与测量结果相联系的参数，它是分析结果可信程度的最重要的依据[5]。国际原子能机构明确规定放射性测量结果不仅要给出量值，还应给出以数量表示的该值的分散程度，即不确定度[6-7]。……