Trace element determination in water samples by on-line isotope dilution and inductively coupled plasma with mass spectrometry detection

This article describes the application of on-line isotope dilution mass spectrometry with inductively coupled plasma (OID-ICP-MS) to the field of trace metal analysis (B, Cd, Cr, Fe, Ni, Pb and Zn) in water samples by the certified reference material (CRM) characterization. Drinking, natural and waste water certified reference materials were analyzed. Emphasis is placed on OID-ICP-MS measurements of highest analytical quality and their validation against direct external calibration mass spectrometry with inductively coupled plasma analysis (ICP-MS). Differences in the calibration strategies such as single OID-ICP-MS versus direct external calibration ICP-MS were discussed. In general, it can be stated that OID-ICP-MS offers high accurate and precise results with small measurement uncertainties, when properly applied, compared to external calibration. Thus, OID-ICP-MS proved to be an ideal solution for routine water sample analysis, increasing sample throughput without any previous sample handling and improving the quality and reliability of the analytical results. (C) 2013 Elsevier B.V. All rights reserved.