People used to eat and drink this toxic substance

Radium is, quite famously, not good for you. Its effects on the body are deleterious, not that anyone realized this when Marie Curie discovered the alkaline earth metal in 1898 — a scientific breakthrough that led to her winning the 1911 Nobel Prize in chemistry. Before long, the dangerously false belief that radium had health benefits began to spread: It was added to everything from toothpaste and hair gel to food and drinks, with glow-in-the-dark paints made from radium still sold into the 1970s.

It was marketed as being good for any “common ailment,” with radioactive water sold in small jars that shops claimed would “aid nature” and act as a natural “vitalizer.”Of course, none of this was true — exposure to even a small amount of radium can eventually prove fatal. Curie had no way of knowing this at the time, just as she didn’t have the slightest inkling that her notebooks would remain radioactive for more than 1,500 years after her death. She was known to store such elements out in the open and even walk around her lab with them in her pockets, as she enjoyed how they “looked like faint, fairy lights.”