In the early 1900s, ionizing radiation and the effects it can have on the human body were widely unknown. While Wilhelm Röntgen and Henri Becquerel discovered that rays could be created using barium and uranium, it was Marie Curie who continued their experimentation and named the phenomenon “radioactivity.” She is credited with discovering the radioactive elements thorium, radium and polonium, and she was awarded the Nobel Prize in Physics (with Henri and her husband, Pierre) for her work in radioactivity, and the Nobel Prize in Chemistry for discovering radium and polonium.

It is indisputable that Marie Curie was one of the most important contributors to the world of science and health care — but she did so at the expense of her own health. As she continued to investigate the subject with her husband, Pierre, Marie carried bottles of polonium and radium in her coat pocket. In some of her notes, she has written that she and Pierre loved visiting their workroom at night and observing the luminescent glow of the bottles containing their radioactive materials.

Marie died in 1934 of aplastic anemia, which researchers believe developed because of her continuous exposure to radioactive elements. Even now, most of Marie’s papers and books are considered to be highly radioactive and are stored in lead-lined boxes. Anyone who wishes to view these materials can only do so after donning a protective suit and signing a liability waiver.

For years after the discovery of radium, people had no idea it could be so harmful. They used radium in toothpaste, bath salts and drinking cups. The 1938 Food, Drug and Cosmetic Act banned radioactive consumer products, but it was too late for the people who had been exposed. Today, we are much more careful about our use of ionizing radiation, but we continue to enhance our level of protection, thanks to products such as digital dosimeters, which measure how much radiation an individual worker receives.