Marie Curie

Marie Skłodowska Curie (7 November 1867 – 4 July 1934) was a Polish-French physicist and chemist who pioneered the study of radioactivity. She shared the 1903 Nobel Prize in Physics and won the 1911 Nobel Prize in Chemistry, becoming the first woman to receive a Nobel Prize and the first person to receive one in two sciences 1.

Her work with her husband Pierre Curie identified polonium and radium, and her insistence on measuring radiation quantitatively turned a puzzling phenomenon into a research programme. During the First World War she organised mobile radiography units for field hospitals, and she spent the 1920s raising money for research institutes in Paris and Warsaw 2.

She died of a blood disease caused by prolonged exposure to radiation, at a time when its hazards were poorly understood.

Maria Skłodowska was born in Warsaw on 7 November 1867, the youngest of five children in a family of teachers. Her mother died of tuberculosis when she was ten, and her father, a teacher of physics and mathematics, kept the household together on a modest salary. Because Polish higher education was restricted under Russian rule, she attended an underground institution known as the Flying University and worked for years as a governess to fund her sister's studies 1.

In 1891 she moved to Paris and enrolled at the Sorbonne, living on very little while she completed degrees in physics in 1893 and mathematics in 1894. She met Pierre Curie, a physicist at the School of Industrial Physics and Chemistry, in 1894, and they married in 1895 2.

Henri Becquerel had shown in 1896 that uranium salts emit penetrating rays without any apparent source of energy. Curie took up the problem with a sensitive quartz electrometer, which measured the ionisation the rays produced, and found that the effect depended only on the amount of uranium present, not on its chemical form. She concluded that the radiation came from the atom itself 2.

Testing other elements, she found that thorium was also active, and she coined the term radioactivity. In 1898 she and Pierre announced two new elements in pitchblende residues from Joachimsthal: polonium, named for her native Poland, and radium. Four years of processing tonnes of ore produced a fraction of a gram of radium chloride, and by 1902 she had determined radium's atomic weight as about 226 3.

The 1903 Nobel Prize in Physics went to Becquerel and to Pierre and Marie Curie for their work on radioactivity. The original nomination named only the two men; Pierre insisted that Marie be included, and the award recognised her contribution to the measurement and theory of the phenomenon 4.

Pierre was killed by a horse-drawn wagon in 1906. Marie took over his chair at the Sorbonne, becoming the first woman to teach there, and continued the research. In 1911 she received the Nobel Prize in Chemistry for the discovery of radium and polonium and for the isolation of radium, a second award that recognised work done largely on her own 5.

When war broke out in 1914, Curie helped equip mobile radiography units, nicknamed the little Curies, and trained women to operate them near the front. Estimates of the number of installations she equipped run to about twenty vehicles and two hundred radiology rooms 2.

After the war she campaigned for radium supplies for the Radium Institute in Paris and for a sister institute in Warsaw, touring the United States in 1921 and again in 1929 to raise funds. The Paris institute opened in 1914 and the Warsaw institute in 1932; both trained generations of physicists and physicians 1.

Curie's long exposure to radium and other radioactive materials damaged her health. She suffered from cataracts and chronic fatigue, and in 1934 she died at Sancellemoz in the French Alps of aplastic anaemia, a failure of the bone marrow that was attributed to radiation exposure 1.

Her notebooks and papers remain radioactive and are stored in lead-lined boxes; visitors who consult them must wear protective clothing. The unit of radioactivity, the curie, was named in her honour in 1910, and the element curium, discovered in 1944, was named for both Curies. Her daughter Irène and son-in-law Frédéric Joliot-Curie shared the 1935 Nobel Prize in Chemistry 3.

Curie's standing rests on more than the prizes. She established radioactivity as a laboratory science, trained a generation of researchers, and insisted that radium be produced and measured with precision, which made it available for medical use. Radium therapy became a standard treatment for some cancers in the early twentieth century, though the risks to patients and workers were recognised only gradually 3.

Her life has been used as a model of scientific perseverance and as a case study in the costs of working with hazardous materials before safety standards existed. The Curie Institute in Paris remains a major cancer research centre, and the Maria Skłodowska-Curie Museum in Warsaw occupies the house where she was born. In 1995 her remains were moved to the Panthéon, the first woman honoured there for her own achievements 2.