
Unexpected Tc-99m detection on a coworker
Hi,
I had an unexpected Radiacode detection today at work and thought it might be interesting for this community.
My Radiacode first started alarming while I was walking to the restroom. On my way back, I tried to locate the source and eventually found that the signal was coming from one of my coworkers.
He told me he had received some kind of medical “cocktail” for a nuclear medicine procedure / contrast-like examination. I measured up to around 4****k cps close to his chest pocket area.
I recorded a spectrum for about 6–7 minutes and attached the screenshot. The main peak appears to be around 140 keV, so my first guess is Tc-99m. There is also a visible feature around 88–90 keV, which I assume is probably backscatter from the 140 keV gamma line rather than a second isotope.
Additional context: he mentioned that the tracer was supposed to accumulate in organs, and he is scheduled for dialysis tomorrow. I am not asking for a medical diagnosis, just curious about the spectrum and isotope identification.
Does this look like a typical Tc-99m medical spectrum to you? And would you also interpret the ~90 keV peak as backscatter?