Abstract
Chemical separation processes are adapted to increase the concentration of the analyte while removing interferences prior to instrumental analysis. In the case of radioactive strontium (Sr-90) analysis in environmental samples, chemical separation is crucial. Yttrium-90, the decay product of Sr-90, can be efficiently purified using solid phase extraction (SPE) with DGA extraction chromatography resin1). This method was employed to analyze seawater samples collected near the Fukushima Daiichi Nuclear Power Plant in 2013. Elevated concentrations of Sr-90 in coastal seawater were observed, suggesting continuous leakage of contaminated water from the reactor building as of May 20132). The DGA SPE method is also applicable for all rare earth elements (REEs). We utilized this technique to analyze neodymium isotopic ratio (143Nd/144Nd atomic ratio), which is useful chemical tracer in geochemistry and marine chemistry3). In addition, we started exploring the application of Nd isotopic ratio to fisheries and archaeology. The Nd isotopic ratio in marine organisms reflects the geographic origin, enabling clear distinction between regions with different geological histories, such as Japan and China.
