火焰原子吸收光谱法测定化妆品中铅的不确定度评定

Evaluation of The Uncertainty of Lead in Cosmetics Determined by Flame Atomic Absorption Spectrometry

目的建立并运用火焰原子吸收光谱法测定化妆品中铅的不确定度评定方法。方法根据《测量不确定度评定与表示》,并参考《化学分析中不确定度的评估指南》,对火焰原子吸收光谱法测定化妆品中的铅进行测量不确定度的分析与评定。结果合成标准不确定度为0.46mg·kg-1,扩展不确定度为0.92mg.kg-1。结论运用该不确定度评定方法对测定过程中的关键环节进行重点质量控制,严格按照操作规范,尽可能减少稀释过程影响,可有效降低引入的不确定度,保证测定结果准确。

Objective To establish the evaluation method of uncertainty for determination of lead in cosmetics by FAAS and to use the evaluation method in quality control of determination process. Methods The uncertainty of lead in cosmetics determined by FAAS was analyzed and evaluated based on ＂Evaluation and Expression of Uncertainty Measurement＂ and ＂Manual of Uncertainty Evaluation in Chemical Analysis＂. Results The combined standard uncertainty and expanded uncertainty were 0.46,0.92mg·kg^-1,respectively. Conclusion The method of uncertainty for determination of lead in cosmetics by FAAS can be used in quality control of determination process. The introduced uncertainty can be effectively reduced and the determination result can be ensured by strictly following the operation standards and trying to reduce the influence of dilution process.