Apparent high tritium intake by a radiation worker at the University of Rochester

On 20 September 1999, a urine sample submitted by a University of Rochester radiation worker was noted to have a count rate of about 759,500 disintegrations per minute (dpm) per milliliter as analyzed on the Radiation Safety Unit (RSU) Packard liquid sintillation counter. The sample was recounted that day with variable results but each time indicating several hundred thousand dpm of activity present. Calculations indicated this corresponded to a whole-body uptake of about 518 MBq (14 nmCi) and a whole-body dose of about 10 msv (1 rem). An investigation indicated it was unlikely for these analytical results to indicate an actual uptake of tritium and suggested the results were most likely due to chemical luminescence in the sample. Accordingly, no dose was assigned to this worker from the exposure.