Abstract:

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).

Key words: cadmium, inductively coupled plasma-mass spectrometry (ICP-MS), graphite furnace atomic absorption spectrometry, measurement uncertainty