Uncertainty Evaluation of Measurement Results for the Determination of Cadmium in Soil Samples by Graphite Furnace Atomic Absorption Spectrometry

Based on The Guide of Uncertainty Evaluation and Denotation for Measurements, uncertainty evaluation of measurement results for the determination of cadmium in soil samples by graphite furnace atomic Absorption spectrometry (GFAAS) was carried out with some examples. The results show that the main sources of the total uncertainty comes from the fraction uncertainties of sample weighting, preparation of various chemical solutions, the certified values of standard reference materials, the instrument stability and etc.. The total uncertainty for the determinations of cadmium by GFAAS was combined and the expanding uncertainty was calculated with value of 0.04×10~ -6 for the soil sample with cadmium content of 0.42×10~ -6 .