eli5 How come if highly radioactive radium was on watches that the wearers didn’t succumb to radiation poisoning at the wrist?

Question

eli5 How come if highly radioactive radium was on watches that the wearers didn’t succumb to radiation poisoning at the wrist?

In: 186

Answer 1

Radium is what we call an Alpha Emiter. It sends off large destructive alpha particles but those are easily blocked. Your outer skin is covered by old dead or dying skin cells that block virtually all of it.

The danger is if it gets inside your body like your lungs or stomach. Inside it will start tearing up the living cells of your organs.