TIL that Vanadium is one of the most effective spermicides discovered. Most spermicides irritate the vaginal wall. Not vanadium. It sneaks inside the sperm and snaps off the tail so it can't swim without external irritation. However, it also messes with blood sugar levels and turns the tongue green.

https://gizmodo.com/this-natural-spermicide-turns-your-tongue-green-16816…
#til #todayilearned
https://www.reddit.com/r/todayilearned/comments/1goaof4/til_that_vanadium_is_one_of_the_most_effective/