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Medical use

Radium (usually in the form of radium chloride or radium bromide) was used in medicine to produce radon gas, which in turn was used as a cancer treatment; for example, several of these radon sources were used in Canada in the 1920s and 1930s. However, many treatments that were used in the early 1900s are not used anymore because of the harmful effects radium bromide exposure caused. Some examples of these effects are anaemia, cancer, and genetic mutations. As of 2011, safer gamma emitters such as Co, which is less costly and available in larger quantities, were usually used to replace the historical use of radium in this application, but factors including increasing costs of cobalt and risks of keeping radioactive sources on site have led to an increase in the use of linear particle accelerators for the same applications.

Early in the 1900s, biologists used radium to induce mutations and study genetics. As early as 1904, Daniel MacDougal used radium in an attempt to determine whether it could provoke sudden large mutations and cause major evolutionary shifts. Thomas Hunt Morgan used radium to induce changes resulting in white-eyed fruit flies.Nobel-winning biologist Hermann Muller briefly studied the effects of radium on fruit fly mutations before turning to more affordable x-ray experiments.

Howard Atwood Kelly, one of the founding physicians of Johns Hopkins Hospital, was a major pioneer in the medical use of radium to treat cancer. His first patient was his own aunt in 1904, who died shortly after surgery. Kelly was known to use excessive amounts of radium to treat various cancers and tumors. As a result, some of his patients died from radium exposure. His method of radium application was inserting a radium capsule near the affected area, then sewing the radium "points" directly to the tumor. This was the same method used to treat Henrietta Lacks, the host of the original HeLa cells, for cervical cancer. As of 2015, safer and more available radioisotopes are used instead.