DETERMINATION OF TRACE-METALS (AS, CD, HG, PB AND SN) IN MARINE SEDIMENT SLURRY SAMPLES BY ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRY USING PALLADIUM AS A CHEMICAL MODIFIER

Methods for the determination of As, Cd, Pb, Hg and Sn by electrotherm al atomic absorption spectrometry in marine sediment slurry samples we re developed. Triton X-100 was used as surfactant to stabilize the mar ine sediment slurry. Palladium or a mixture of palladium and magnesium nitrates was used as a chemical modifier. With the use of these modif iers it was possible to stabilize As, Cd, Pb, Hg and Sn to temperature s of 1200, 700, 900, 200 and 1300 degrees C respectively, and the opti mum atomization temperatures were 2300, 2500, 2500, 1450 and 1900 degr ees C. Precision and accuracy of the method were investigated using th e marine sediment reference material PACS-1 (National Research Council Canada). The detection limits were 44, 0.08, 60, 70 and 57 mu g kg(-1 ) for As, Cd, Pb, Hg and Sn respectively.