My Radioactive Student

Note from Dr. about Tc-99m

Note from Dr. about Tc-99m

Yesterday a student came up to me and explained that she had been injected with a radioactive isotope for a medical scan.  She then asked if she was still radioactive.

Expecting the isotope to be mostly decayed or simply too small to notice, I wanted to calm her fears with a Geiger counter check.

The results surprised me, and she allowed me to take a video (her face is not shown for privacy) shown below.  You can listen carefully to the ‘clicks’, which rapidly increase as I approach her.

It turns out that her doctor gave her a note (right) explaining that the isotope was Technetium-99m – commonly used for medical scans (more information about Tc-99m can be found from the Brookhaven National Laboratories).  Tc-99m has a half-life of 6 hours (she had the scan 4 hours earlier), so she still had a significant amount present in her body.

Leave it to a science teacher to find this interesting.


My Radioactive Student from Brian Bartel on Vimeo.

One comment

  • Techy Nana

    As a science teacher you just happened to have a geiger counter in your classroom?! I’m impressed. This is a really cool example of a teachable moment but did it allay her fears after all?

Leave a Reply