I have a couple of the little suckers. In my ear, they start to hurt after about 30 minutes. Nose / mouth - no pain because there's more in between the two magnets. I still don't see how you could leave them on for so long that you'd have dead tissue on your ear / lip / groin.

Now, how someone could swallow both halves of the magnet, let alone at slightly different times, to clamp together portions of their interior is beyond me.