Rapid bioassay is very important for immediate and near-term consequence management, which includes identifying contaminated individuals and providing necessary medical intervention during a radiological or nuclear emergency. This paper reports the application of a newly developed bioassay technique for (90)Sr in urine on a field deployable instrument, the Triathler. Performance of this field technique for sensitivity, accuracy and repeatability is evaluated against bioassay criteria (ANSI N13.30). This field technique offers the following analytical merits: (1) minimum detectable activity of 121 Bq l(-1) when 20 ml of urine is used; (2) relative bias of 11.1 % and relative precision of 3.2 % at the level of 45 Bq per 20 ml of urine and (3) sample turnaround time of less than 1 h. The technique meets the requirements for emergency bioassay when a committed effective dose of 0.5 Sv is used as the action dose threshold for medical intervention. Sample throughput can be significantly improved if this technique is automated.

The Global Health Security Initiative (GHSI) established a laboratory network within the GHSI community to develop collective surge capacity for radionuclide bioassay in response to a radiological or nuclear emergency. A recent exercise was conducted to test the participating laboratories for their capabilities in screening and in vitro assay of biological samples, performing internal dose assessment, and providing advice on medical intervention, if necessary, using a urine sample spiked with a single radionuclide, 241Am. Laboratories were required to submit their reports according to the exercise schedule and using pre-formatted templates. Generally, the participating laboratories were found to be capable with respect to rapidly screening samples for radionuclide contamination, measuring the radionuclide in the samples, assessing the intake and radiation dose, and providing advice on medical intervention. However, gaps in bioassay measurement and dose assessment have been identified. The network may take steps to ensure that procedures and practices within this network be harmonized and a follow-up exercise be organized on a larger scale, with potential participation of laboratories from the networks coordinated by the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO).