The following is a summary of information that was provided by the licensee via phone and follow-up email:
On 8/4/2023 at 1000 CDT, at SSM St. Clare Hospital in Fenton, MO, an oncologist implanted an I-125 prostate seed. After completion of the implant, a radiation oncology physicist went to the hot lab to return the backup seeds that had not been used. The first four unused needles had a single seed, which was expected. The next two had two seeds, which was expected. The last needle, was expected to have three seeds. However, when the physicist pushed the "stylette," the bone wax came out, followed by just one seed. The physicist surveyed the package, but there were no seeds in it. The final needle was still sealed in its sterile package, thus the physicist believed the seed could not have fallen out anywhere but into the sealed package itself. The physicist surveyed the hot packaging with a Geiger-MÂller counter and found no radioactivity. The physicist surveyed the entire hot lab, and found no activity. An investigation is ongoing with the vendor. Unaccounted for activity was 0.504 mCi of I-125 on the date of the event.
THIS MATERIAL EVENT CONTAINS A 'Less than Cat 3' LEVEL OF RADIOACTIVE MATERIAL
Sources that are "Less than
IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as
moisture density gauges or thickness
gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to
http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf