Determination of mercury compounds in water samples by liquid chromatography inductively coupled plasma mass spectrometry with an in situ nebulizer/vapor generator

A preliminary study of a cold vapor generation system as the sample introduction device for liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS) is described. Samples containing ionic mercury compounds mere subjected to chromatographic separation before injection into the cold vapor generator, The species studied include inorganic mercury (Hg-II), methylmercury and ethylmercury. The sensitivity, detection limits and repeatability of the LC-ICP-MS system with a cold vapor generator were comparable to or better than those for an LC-ICP-MS system with conventional pneumatic nebulization or other sample introduction techniques. The limits df detection for various mercury species were in the range 0.03-0.11 ng ml(-1) Hg based on peak height. The concentrations of mercury compounds in open ocean sea-water reference material NASS-4 and a tap water sample collected from National Sun Yat-Sen University were determined.