I hesitate to share this, but... *MATURE CONTENT ALERT*
In the 20's to early 30's there was a famous case of Eben Byers, a guy who dabbled in radioactive salts dissolved in water. At the time he more or less had it all, being a wealthy guy, successful in his endeavors, as well as an accomplished sportsman. Then a fake doctor and quack recommended his unregulated patent medicine "Radithor" for a sports injury.
At first Byers really did experience some benefits, but then started to feel... not so good. So he doubled down and increased his consumption, being absolutely confident in the stuff. Well, that process repeated until his lower jaw started rotting away, until eventually the lower part of his face was just... gone.
The late stage-pics are absolutely wild to me. It's hard to understand how someone could survive like that, but it seems he somehow lasted five years while on Radithor, dying of cancer in the end.