One fell out of my ear when I looked in the bathroom mirror, bounced on the counter and dropped into the toilet. It was in there for a few seconds as it was slippery as hell. I wiped it down with a paper towel, wiped around it with a Q-Tip and then cleaned/sterilized it with another Q-Tip with isopropyl alcohol.
Even though they're water/sweat resistant you can't obviously submerge them.