Determination of Cadmium in Sea Water by ICP-MS with Chelating Resin Preconcentration

An analytical method for the detection of cadmium in sea water samples by using Inductively Coupled Plasma Mass Spectrometry with a chelating resin solid-phase extraction (SPE) method was developed. The MCM resin in a syringe-driven chelating column was investigated in the present experiment. Using this resin, Cd and Mo were preconcentrated at pH 3.5; further, matrix elements such as Na, K, Mg and Ca were removed under the same conditions. In other words, under pH conditions over 10, Mo is eluted though Cd is maintained. It was shown that the separation of Cd and Mo could be obtained. Using this method, it was possible to analyze under ng L-1 Cd without interferences from Mo. The present method was validated by analyzing five certified reference materials, and then the vertical distribution of Cd concentration in the sea water around Japan Island was obtained.