After a series of preliminary experiments to examine the problems involved with interfacing an on-line ion exchange system with an inductively coupled plasma mass spectrometer, a sixty second sample load time was found to provide adequate sensitivity at the 0.1 ng·ml−1 level. Instrumental response was found to vary linearly with analyte concentration over the range of concentrations required for the analysis of real, environmentally important, samples. By careful optimisation of the interfaced system, detection limits of less than 0.5 ng·ml−1 were produced for Al, Cr, Mn, Co, Ni, Cu, Zn, Cd, Hg and Pb in an aqueous solution containing 3% sodium chloride as a matrix.