在食品样本中同时测定Ra226和Ra228的含量,使用液体闪计数
Qishan Zheng1, Yao Zhang2, Liangliang Yin1
1China CDC Key Laboratory of Radiological Protection and Nuclear Emergency, National Institute for Radiological Protection, China CDC, Beijing 100088, China.
Food chemistry
|November 23, 2023
概括
这项研究提出了一种新的,具有成本效益的方法,用于测量食物中的放射性同位素 (Ra和Ra). 开发的液体闪计数技术提供了准确的检测,解决了人们对消费食品中放射性毒性的公共卫生问题.
科学领域:
- 环境科学 环境科学
- 分析化学 分析化学
- 食品安全 食品安全
背景情况:
- 同位素 (Ra226和Ra228) 是重要的食品污染物,具有放射性毒性风险.
- 现有的分析方法主要应用于水和环境样本,而不是食品.
- 准确确定食物中的对于公共健康和安全至关重要.
研究的目的:
- 开发一种具有成本效益的方法,用于在食品样本中同时确定Ra和Ra.
- 用经过认证的参考材料验证开发的方法,并与现有技术进行比较.
- 为评估食物链中的污染提供可靠的分析工具.
主要方法:
- 开发一种液体闪计数 (LSC) 方法,用于同时进行226Ra和228Ra分析.
- 优化食品矩阵的样本制备,包括灰化.
- 使用国际原子能机构 (IAEA) 认证的参考材料进行验证.
主要成果:
- 在Ra226的总效率达到69.4-78.4%,在Ra228的总效率达到30.1-35.8%.
- 确定最小可检测活动 (MDA) 为Ra226的11.3 mBq/g和Ra.228的33.4 mBq/g.
- 该方法根据国际原子能机构的标准进行了验证,并且与真实食品样本 (茶,海藻,) 的玛光谱数据有很好的一致性.
结论:
- 开发的LSC方法是有效和经济高效的,用于同时确定食品中的Ra和Ra.
- 该方法为食品安全监测和与污染相关的风险评估提供了宝贵的工具.
- 该研究解决了食品矩阵中同位素分析能力的差距.
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