Answer to Question #535 Submitted to "Ask the Experts"

Q

I've read that Marie Curie died from overexposure of radiation. I was wondering what type of experiments she was doing at the time and what type of (physical) problems she developed because of it?

A

Marie Curie's main claim to fame was her discovery and characterization of the highly radioactive element radium. Much of this work involved a tedious chemical separation of the radium from uranium ore. As a result, her body received an external exposure from the gamma rays emitted by the radium and its decay products, her fingers received substantial exposures from the beta particles and gamma rays emitted by the radium, her lungs received an exposure due to the inhalation of the radioactive gas radon produced by the radium, and her skeleton (and bone marrow) received an exposure from the radium that she accidentally ingested. In addition to these exposures from radium, she also received a significant exposure from x rays when she operated mobile x-ray units near the front lines during the first world war. Throughout her adult life she was in a constant state of ill health. In fact she was sometimes accused by other scientists of using her ill health as a tactic to get her way. This ill health manifested itself in several ways; for example, she continually rubbed her fingertips together because of the radiation damage to them from handling sources, she developed cataracts (the lens of the eye is particularly sensitive to radiation), and she was constantly fatigued. Marie Curie died in 1934 of what her doctor, Dr. Tobe, described as "an aplastic pernicious anemia of rapid, feverish development" (Curie 1937). This is almost identical to the diagnosis given for the first reported radiation-related death of a radium dial painter: "rapidly progressing anemia of the pernicious type" (Martland 1925). It has been argued that her death could not have been due to radium because pernicious anemia is not now believed to be caused by radiation exposures. The problem with this argument is that what her doctor was referring to was probably not what we now call pernicious anemia. Indeed, her daughter, Eve Curie, wrote (1937): "the abnormal symptoms, the blood tests, differing from those in any known case of pernicious anemia, accused the true criminal: radium." Marie's eldest daughter and collaborator, Irene Curie, died in her mid-50s of leukemia. Reference: Curie, E. Madame Curie. Doubleday; Garden City, NY; 1937. Paul Frame, CHP, Ph.D.