Determination of As, Bi and Se in acidified slurries of marine sediment, soil and coal samples by hydride generation electrothermal atomic absorption spectrometry

Ir-treated graphite tubes were used for preconcentration and atomisation of the As, Bi and Se hydrides generated from acidified slurries of marine sediment, soil and coal samples. A batch mode generation system was used for the hydride generation. The variables affecting the acidified slurry preparation procedure (assisted by ultrasonic energy) and the hydride generation/trapping/atomisation processes were studied by using a Plackett-Burman design. The sensitivity (characteristic masses of 65, 75 and 100 pg, for As, Bi and Se, respectively) and precision (RSD% lower than 10%) obtained were adequate for As, Bi and Se determination in slurry samples. The accuracy of the method was verified by analysing PACS-1 (Marine Sediment), GBW-07401 (Soil) and NIST SRM 1632c (Coal) certified reference materials.