TIL that Bismuth, the active ingredient in Pepto-Bismol, technically has no stable isotopes - however its most stable and common isotope has a half-life more than a billion times the age of the universe. (Some more facts in the comments)

https://en.wikipedia.org/wiki/Bismuth
#til #todayilearned
https://www.reddit.com/r/todayilearned/comments/1g0x3lq/til_that_bismuth_the_active_ingredient_in/