A COLLABORATIVE STUDY USING SOLID SAMPLING GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY

A first collaborative study was carried out to test the precision and accuracy of solid sampling graphite furnace atomic absorption spectrometry (SS-ZAAS). Seven test materials, i.e. red cabbage, two bovine liver materials, milk powder (BCR 150), kale, industry dust, and fish homogenate were sent to 11 participants. These test materials were analyzed for cadmium, lead, copper and mercury. Precision was calculated as the repeatability (r) and the reproducibility limits (R). Accuracy was calculated with respect to the Certified Reference Material BCR 150, milk powder. Results showed that the accuracy for milk powder was excellent, and that most results regarding repeatability and reproducibility limits were satisfying. However, some problems were met especially with copper in bovine liver and cadmium and copper in industry dust. It was not clear what caused the problems: the method SS-ZAAS or the inhomogeneity of the material. Especially the industry dust test material has to be studied further in order to locate the origin of the problems.