RESUMEN
Argon-supported inductively coupled plasmas operated at atmospheric pressures are excellent vaporization-atomization-excitation-ionization sources for analytical atomic emission spectroscopy. When a polychromator is used for observing the emitted spectra, the metals and metalloids can be determined simultaneously at the ultratrace, trace, minor, and major concentration levels under one set of experimental parameters. Alternatively, programmable scanning spectrometers may be utilized for sequential determinations. The atomization-excitation process is remarkably free of interelement interactions, the powers of detection are in the part per billion range for most elements, and sample manipulation requirements prior to analyses are often minimal. The technique meets the requirements of an analytical system for the simultaneous or sequential determination of the elements at all concentration levels to an unusual high degree.
RESUMEN
Methods are presented for the determination of methylmercury in fish, water, urine, and sediments, and diorganomercury compounds in water. Two significant differences from previous methods are the use of methylene chloride extracting solvent which permits sample extracts to be concentrated to volumes as low as 0.1 mL, and use of a gas chromatograph interfaced to an atmospheric pressure active nitrogen (APAN) afterflow detector. Such a detector is very sensitive and selective for Hg at picogram levels. Thus, limits of detection were significantly enhanced.