固相萃取-气相色谱质谱法测定饮用水中莠去津的不确定度评估

Evaluation of Uncertainty in Determination of Atrazine in Drinking Water by Use of GC/MS Using Solid-phase Extraction

根据《生活饮用水标准检验方法有机物指标标准》(GB/T5750.8-2006)附录B中的检测原理和方法,并结合JJF 1059-1999《测量不确定度评定与表示》和CNAS-GL06《化学分析中不确定度的评估指南》,对固相萃取-气相色谱质谱法测定饮用水中的莠去津浓度的不确定度进行了评估计算。分析了莠去津浓度测定过程中影响不确定度的各种来源,并对其引入的不确定度进行测算。合成了相对标准不确定度及相对扩展不确定度。结果表明,当水中莠去津的浓度为0.215μg/L时,检测结果表示为(0.215±0.00752)μg/L。固相萃取富集过程引入的不确定度对测量结果的影响最大。

According to the detection principles and methods given in the appendix B of the Standard Examtnation Methods of Drinking Water-Organic Parameters（ GB/T5750. 8-2006）,the description in the Guidance on Evaluating the Uncertainty in Chemical Analysis（ CNAS-GL06）,and the Evaluation and Expression of Uncertainty in Measurement（ JJF 1059-1999）,uncertainty of the determination of atrazine concentration in drinking water by Gas Chromatography-Mass Spectrometry using solid-phase extraction was evaluated. Various sources of uncertainty in the determination process of atrazine were analyzed and the uncertainty of the process was calculated. The relative standard uncertainty and the relative expanded uncertainty were synthesized. The assessment results showed that the detection result presented as 0. 215 ± 0. 00752 μg/L when the atrazine concentration in water was 0. 215 μg/L, and the solid-phase extraction had the greatest impact on the uncertainty of the measurement.