Determination of Hg and Bi by electrothermal vaporization inductively coupled plasma mass spectrometry using vapor generation with in situ preconcentration in a platinum-coated graphite furnace

Vapor generation electrothermal vaporization inductively coupled plasma mass spectrometry (VG-ETV-ICP-MS) has been applied to the determination of Hg and Bi in several water reference samples. Hg and Bi in the samples were converted into vapors before being transported to the graphite tube of the electrothermal vaporization sample introduction system. Graphite tubes were pretreated with platinum for the adsorption of the vaporized analytes. After a period of trapping, the vapor adsorbed on the graphite tube was desorbed and transported to the ICP-MS for the quantification of Hg and Bi. With this sample introduction system, a detection limit of 15 and 3 pg ml(-1) was obtained for Hg and Bi, respectively. Repeatability of the signal was better than 7% for Hg and Bi in various sample matrices. Since the recoveries were slightly less than 100%, the concentrations of Hg and Bi in the reference materials were quantified by the standard addition method. VG-ETV-ICP-MS method has been applied to the determination of Hg and Bi in open ocean seawater reference material NASS-3, nearshore seawater reference material CASS-3 and riverine water reference material SLRS-2. (C) 1997 Elsevier Science B.V.