3. Radium Girls

Throughout history, humans have discovered new elements and substances that are lauded as huge scientific advancements. Sometimes, these discoveries end up being more harmful than useful, but we don’t discover their negative impact until more research is done decades later. That’s the case with radium. The radioactive element was discovered in 1898 by Marie Curie, and a radium craze followed soon thereafter. 

Radium was celebrated for its health benefits and its ability to glow in the dark was seen as a miracle for watchmakers. The U.S. Radium Corp hired whole crews of female factory workers to paint tiny numbers with radium paint. It was thought to be a well-paying job, but these women started getting sick within a few years. The “Radium Girls,” as they’re collectively called, are the unfortunate reason we discovered how toxic radium is to the human body.