The notebooks Marie Curie used in her research remain radioactively contaminated more than a hundred years later. Some Curie papers have been found contaminated with radium-226, an isotope with a half-life of about 1,600 years, and original volumes are kept under strict radiation-protection controls before anyone can handle them.

Marie Curie's notebooks are still radioactive, contaminated mainly with radium-226 (half-life about 1,600 years). Stored at the Bibliotheque nationale de France in lead-lined boxes, they require a waiver and protective gear to handle, and will stay hazardous until around the year 3500. The post The notebooks Marie Curie used in her research remain radioactively contaminated more than a hundred years later. Some Curie papers have been found contaminated with radium-226, an isotope with a half-lif