A rapid fecal bioassay method for Pu/Am

Fecal radiobioassay is a sensitive tool to estimate intake of radionuclides , especially for insoluble or poorly absorbed actinides. To increase effici ency and reduce turnaround time, improvements were introduced in the sample digestion step of a fecal bioassay method to rapidly detect Pu and Am. The acid- and microwave-digestion of the spiked fecal samples (5-10 g) were ef fectively completed in 1 h. The turnaround time for the sample analysis was minimized to 6 h. The average recoveries for Fu and Am were 35% and 60% fo r artificial fecal samples, respectively. Much better recoveries for Pit an d An were obtained for natural fecal samples. Observed relative biases for Pu and Am were marginally in the range of -0.25 to +0.50. The relative prec ision values for both radionuclides were, however, within the performance i ndex of 0.4. This rapid fecal method is a potential candidate for an accept able quantitative radiobioassay and screening method for the suspected Pu/A m exposures.