Thank you. This is interesting, and it’s absolutely the radon issue that I was more concerned about. Lots of people tend to focus only on the alpha particles and how you would need to breath in or ingest the radium dust itself to cause an issue, when it’s actually much more complicated than that. As I mentioned I literally tested this on a shelf with a Geiger counter a while ago, and I’ve just rerun some tests. Now I remember why I was concerned…
I attach the photos, but as you can see, immediately in front of the dial (where you are unlikely to be, unless you fall asleep with your watch on?), it goes off the scale and records something over 9.99 micro Sieverts per hour. Measured from behind the watch case (ie your wrist), the dose is 2.18 micro Sieverts per hour. Finally, six inches in front of the face, it’s 1.55 micro Sieverts per hour.
As can be seen from the final image “How much is dangerous” which came with the Geiger counter, it states that 1.25 micro Sieverts per hour gives you a real risk of cancer if exposed for a year. That’s much below what your wrist would experience, and who knows how long you’d have to be near the face for it to be a concern.
Anyway, hopefully someone will find this helpful, and from real-world data.