Methodology for determination of 89Sr and 90Sr in radiological emergency : scenario dependent evaluation of potentially interfering nuclides

Determination of 89Sr and 90Sr in radiological emergency, e.g. a nuclear power plant (NPP) accident or nuclear weapons fall-out, is hampered by the presence of short-lived fission products that may interfere in the measurement. The 89,90Sr radioanalytical procedures most extensively used today were, in this report, compiled and evaluated with respect to their suitability in different emergency scenarios. Calculation were performed on the relative acitivities of short-lived strontium and yttrium isotopes and other elements known to be difficult to fully separate from strontium and yttrium, e.g. barium and the lanthanides. The effects of chemical separations at different times after an initial release were calculated. A summary of how soon different analytical strategies can provide useful determinations after the initial release is supplied. An analytical strategy based on an initial separation of strontium and determination of 89Sr, followed by an additional yttrium separation and counting of 90Y was found to be the most successful approach for determination of both 89Sr and 90Sr. Using this approach, 89,90Sr can be determined 5 and 9 days after a nuclear weapons detonation, respectively, or approximately 2 and 3 days after a NPP accident. Calculations also show that a separation of barium to prevent interference from 140Ba and 140La most likely will be necessary.