ICP-MS法和石墨炉原子吸收法测定大米中镉含量不确定度评估的比较

采用电感耦合等离子体质谱法和石墨炉原子吸收法分别测定大米中的镉含量。比较全面地考虑了整个测定过程的不确定度来源，对影响结果不确定度的各个因素作了系统分析，建立了结果不确定度评估数学模型，探讨了其测定结果不确定度，并对评估结果进行比较。当镉的测定结果为限量值附近（0.20 mg/kg）时，2 种方法的扩展不确定度分别为0.020、0.034 mg/kg，k=2。

Comparative Study of Uncertainty Evaluation for the Determination of Cadmium Content in Rice by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Graphite Furnace Atomic Absorption Spectrometry

The content of cadmium in rice was determined by inductively coupled plasma-mass spectrometry (ICP-MS) and
graphite furnace atomic absorption spectrometry, respectively. The sources of uncertainty in the measurement process were
comprehensively considered. The various factors that affect the uncertainty were systematically analyzed. A mathematical
model for uncertainty evaluation was established and used to comparatively evaluate the uncertainties of the two analytical
methods. The expanded uncertainties of these two methods were 0.020 and 0.034 mg/kg (k = 2), respectively, when the
determination results of cadmium were close to the maximum allowable limit (0.20 mg/kg).