I remember doing that test with you, scary but no worries on wrist >
The histoical Panerai watches that were so radioactive, have been destroyed long time ago. As for those of the 50's my understanding is that they cannot endanger one's life, the amount of radioactivity is a few 1000s of time lesser that what we breath daily.
Anyway if you are worried about it, send it to me... :-)
YvesOdier TTT