A comparison of trace level concentrations for silver, arsenic, barium, cadmium, and lead in drinking waters obtained by inductively coupled plasma-mass spectrometry and electrothermal-vaporization atomic absorption spectroscopy

We compared the data obtained by inductively coupled plasma-mass spectrometry (ICP-MS) and electrothermal-vaporization atomic absorption spectroscopy (ETVAA), for concentration values of silver, arsenic, barium, cadmium, and lead in drinking water specimens, spiked analyte recoveries, and control samples. Our goal was to obtain Environmental Protection Agency approval for the ICP-MS as an alternate analytical technique. We obtained similar concentrations for those metals in the natural waters by both methods. Several of the spike recoveries and control sample recoveries, however, varied significantly. Those recoveries indicated a greater level of confidence for the arsenic and barium analytical data obtained using the ICP-MS method. In addition, ICP-MS has rapid multielement analytical technique capabilities with limits of quantification and data confidence comparable to those of ETVAA. Those multielement capabilities and the relative ease of obtaining data make ICP-MS the preferred analytical technique. 5 refs., 8 tabs.