[Sequential injection vapor generation atomic absorption spectrometric determination of mercury and arsenic]

A sequential injection vapor generation atomic absorption spectrometric (SI-VGAAS) method for the determination of mercury and arsenic was developed, characterized by reagent merging using a double-syringe pump and a multi-position selector valve. A sample throughput of 120 h-1 was achieved with 500 microL sample with a precision of 2.2% for mercury at 8.0 micrograms.L-1 (n = 11) and 1.4% for arsenic at 6.0 micrograms.L-1 (n = 11) levels and a detection limit of 0.15 microgram.L-1 for mercury and 0.07 microgram.L-1 for arsenic. The method was applied to the analysis of geochemical standard reference material GSS-5, and good agreement with the certified values were obtained.