 Discovery Information
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| Who: Pierre and Marie Curie |
| When: 1898 |
| Where: France |
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| Name Origin
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| Latin: radius (ray). |
| "Radium" in different languages. |
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| Sources
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| Found in uranium ores at 1 part per 3 million parts uranium.
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| Abundance
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| Earth's Crust: 1 x 10-7 ppm
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| Seawater: 2 x 10-11 ppm
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| Human: |
| 1 x 10-6 ppb by weight
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| 3 x 10-8 ppb by atoms
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| Uses
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| Used in treating cancer because of the gamma rays it gives off. |
| Formerly used in self-luminous paints for watches, clocks and instrument dials. More than 100 former watch dial painters who
used their lips to shape the paintbrush died from the radiation. Soon afterward, the adverse effects of radioactivity became
widely known. Radium was still used in dials as late as the 1950's. Objects painted with this paint may still be dangerous,
and must be handled properly. Currently, tritium is used instead of radium. Although tritium still carries some risks, it is considered by many to be safer than radium.
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| History
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| Radium was discovered by Maria (Sklodowska) Curie and her husband Pierre in 1898 in pitchblende/uraninite from North Bohemia (area around Jachymov). While studying pitchblende the Curies removed
uranium from it and found that the remaining material was still radioactive. They then separated out a radioactive mixture consisting
mostly of barium which gave a brilliant red flame colour and spectral lines which had never been documented before. In 1902 radium was isolated
into its pure metal by Curie and Andre-Louis Debierne through the electrolysis of a pure radium chloride solution by using
a mercury cathode and distilling in an atmosphere of hydrogen gas.
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| During the 1930s it was found that workers exposure to radium by handling luminescent paints caused serious health effects
which included sores, anemia and bone cancer. This use of radium was stopped soon afterward. This is because radium is treated
as calcium by the body, and deposited in the bones, where radioactivity degrades marrow, and can mutate bone cells. The litigation
and ultimate deaths of five "Radium Girl" employees who had used radium-based luminous paints on the dials of watches and
clocks had a significant impact on the formulation of occupational disease labour law.
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| Notes
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| At the turn of the 20th century radium was a popular additive in products like toothpaste, hair creams, and even food items
due to its supposed curative powers. Such products soon fell out of vogue, and were prohibited by authorities in many countries,
after it was discovered they could have real and serious adverse health effects.
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| Hazards
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| Radium is highly radioactive and its decay product, radon gas is also radioactive. Since radium is chemically similar to calcium, it has the potential to cause great harm by replacing it in the bone.
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| Radium is over a million times more reactive than an equivalent mass of Uranium.
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| Handling of radium has been blamed for Marie Curie's premature death.
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