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This paper describes a method for speciation of Hg associated with airborne particulate matter. This method uses a mini-sampler for sample collection and analysis, thermal desorption for separating Hg species, and inductively coupled plasma mass spectrometry (ICP-MS) for identification and quantification of Hg. Coal fly ash spiked with different Hg compounds (e.g. Hg0, HgCl2, HgO, and HgS) was used for qualitative calibration. A standard reference material with a certified value for Hg concentration was used to evaluate the method. When the temperature of the furnace was programmed at a linear rate of increase of 50 degrees min(-1), different Hg compounds could clearly be separated. Three airborne particulate matter samples were collected in parallel in Toronto, ON, Canada and analyzed using this method. Reproducible results were obtained and Hg0, HgCl2, HgO, and HgS species from these samples were detected.

A method for the determination of B isotope ratios In a variety of geological materials Is described. Boron isotope ratios are determined with a precision of 0.7 % In materials containing as little as 0.5 ppm B. Sample material Is leached with HCI In sealed pressure tubes or fused with sodium carbonate. Separation and/or preconcentration of B from matrix elements Is accomplished by using AmberlHe XE-243, Dowex 50W-X8, or Chetex-100 resins. The use of NASS-1 reference seawater Is suggested as a reference material for calculating and comparing isotope shifts for different geological materials. Nonspectroscoplc Interferences due to the presence of concomitant elements In solution are shown to cause 11B Ion count rate suppression at concentrations of Na above 2000 ppm. The presence of excess amounts of concomitant elements causes a matrix-induced mass discrimination effect. Boron Isotope ratios (11B/10B) for the materials studied ranged from 3.91 to 4.18 for basalt and seawater samples, respectively.