OPTIMIZATION AND USE OF FLOW-INJECTION VAPOR GENERATION INDUCTIVELY COUPLED PLASMA MASS-SPECTROMETRY FOR THE DETERMINATION OF ARSENIC, ANTIMONY AND MERCURY IN WATER AND SEA-WATER AT ULTRATRACE LEVELS

Vapour generation flow injection inductively coupled plasma mass spectrometry (FI-ICP-MS) was used for the determination of As, Sb and Hg in four international water reference materials (National Research Council of Canada). A commercially available FI device was easily connected to the ICP-MS system. Flow injection parameters such as sample volume, purge gas flow rate and concentration of reductant were investigated and optimized (univariate) as were different sample pre-reduction techniques. The precision and accuracy of the results obtained show the applicability of this method to the determination of vapour-forming elements at ultratrace levels in environmental samples. Detection limits are in the range 0.5-7 ng l-1 for Bi, Sb, Se-82, Te, Hg and As (with pre-reduction).