浅谈石墨炉原子吸收光谱法检测白酒中铅含量的不确定度

Discussion on Uncertainty in Determination of Lead in Liquor by Graphite Furnace Atomic Absorption Spectrometry

按照《食品安全国家标准食品中铅的测定》GB5009.12—2017,采用石墨炉原子吸收光谱法检测白酒中铅含量,对整个测量过程的不确定度来源进行分析评定,影响白酒中铅含量测量结果的不确定度来源主要有标准使用液引起的相对标准不确定度、试样消化液定容体积引起的相对标准不确定度、试样移取体积引起的相对标准不确定度、原子吸收光谱仪引起的相对标准不确定度等引入的不确定度,经计算得白酒中铅含量测量的合成不确定度为ur(X)=0.0344,最终得出白酒中重金属铅的含量表示为8.0076±0.0344(μg/L)[k=2]。

According to national standard GB 5009.12-2017, using graphite furnace atomic absorption spectrometry to detect lead content in liquor, the uncertainty source of the whole measurement process is analyzed and evaluated, and the uncertainty of the result of determination of lead content in liquor is mainly the relative standard uncertainty caused by standard use liquid, The relative standard uncertainty caused by the volumetric volume of the sample＇s digestive fluid the uncertainty of the relative standard uncertainty caused by the sample removal volume, the relative standard uncertainty caused by the Atomic absorptionspectrometer, and so on, have been calculated as the synthesis uncertainty of the total ester is ur（X） = 0.0151, Finally, the content of heavy metal lead in liquor was expressed as 8.4784±0.0302（UG/L） [k=2].