Who Was Marie Curie? Two Nobel Prizes and a Notebook Still Too Radioactive to Handle

Born Maria Sklodowska in Warsaw in 1867, in a Poland under Russian rule where the language and history were suppressed in schools, she could not attend university because women were not admitted. She studied instead at the Flying University, an illegal itinerant institution that met in private homes, and worked for several years as a governess, sending money to support her sister's medical studies in Paris on the agreement that the favour would be returned. She arrived in Paris in 1891 at twenty-four, enrolled at the Sorbonne, lived in an unheated attic on very little food, and finished first in her class in physics and second in mathematics. She met Pierre Curie in 1894 through a mutual acquaintance who thought he might have laboratory space for her, and they married the following year, with her wedding outfit chosen as a dark dress she could wear in the laboratory afterwards.

Henri Becquerel had found in 1896 that uranium salts fogged a photographic plate through opaque paper, and she took this as her doctoral subject when nobody else regarded it as interesting. Her decisive contribution was methodological: instead of photographic plates she used an electrometer Pierre and his brother had built, which measured the tiny electrical conductivity the rays induced in air and therefore turned the phenomenon into a quantity. That let her establish two things. The emission was proportional to the amount of uranium present and was unaffected by temperature, chemical state or anything else she tried, from which she concluded that it was a property of the atom itself rather than of any molecular arrangement, an idea that contradicted the assumption that atoms were indivisible. And certain ores were far more active than their uranium content could explain, which meant they contained something else. She and Pierre processed tonnes of pitchblende residue in a shed with a leaking roof, and in 1898 announced two new elements, polonium, named for her occupied homeland, and radium. Isolating a tenth of a gram of radium chloride took four more years of grinding, dissolving and crystallising.

Her career is a sequence of firsts obtained against resistance:

• •The 1903 Nobel Prize in Physics, shared with Pierre and Becquerel, was initially to have gone to the two men alone, and was extended to her after Pierre insisted
• •Pierre died in 1906, run over by a horse-drawn cart in a Paris street, and she took over his professorship, becoming the first woman to teach at the Sorbonne
• •The 1911 Nobel Prize in Chemistry was hers alone, for the discovery and isolation of radium and polonium
• •The French Academy of Sciences rejected her candidacy in 1911 by two votes, and did not admit any woman until 1962
• •The 1911 prize coincided with a press campaign over her relationship with the physicist Paul Langevin, in which stolen letters were published and a crowd gathered outside her house, and she was advised not to attend the ceremony, which she ignored
• •She refused to patent the radium isolation process, on the principle that it belonged to science, which meant she never profited from an industry worth a great deal

The contribution she regarded as most immediately useful came in 1914. Recognising that X-ray equipment existed in hospitals far from the fighting and that surgeons at the front were operating without it, she raised funds, obtained vehicles, had them fitted with X-ray apparatus and a generator, learned to drive and to maintain them herself, and organised twenty mobile units and some two hundred fixed installations. She trained around a hundred and fifty women as operators, and worked at the front with her seventeen-year-old daughter Irene. The units are estimated to have examined over a million wounded men, allowing shrapnel and bullets to be located before surgery. She also promoted the use of radon collected from her radium supply to sterilise infected tissue. She received no recognition from the French state for any of this at the time.

The dangers were not understood during most of her career, and she carried tubes of radium in her pockets, kept a glowing sample by her bed because she found it beautiful, and worked for decades with no shielding. She died in 1934 of aplastic anaemia, a failure of the bone marrow almost certainly caused by prolonged radiation exposure. Her daughter Irene Joliot-Curie won the Nobel Prize in Chemistry in 1935 with her husband for the discovery of artificial radioactivity, making the family the most decorated in the history of the prizes, and died of leukaemia at fifty-eight. The institute Marie Curie founded in Paris remains a major cancer research centre, and radiotherapy descends directly from her work. She was reinterred in the Pantheon in 1995, the first woman placed there on her own merits, and the unit of radioactivity, the curie, carries the family name.

Barred from university in Russian-ruled Poland, she studied at an illegal itinerant institution, reached Paris at twenty-four and made the phenomenon of radioactivity measurable with an electrometer, establishing that it is a property of the atom itself and that unexplained activity in ores implied undiscovered elements. She and Pierre isolated polonium and radium from tonnes of residue, she won Nobel Prizes in physics and chemistry, refused to patent her process, ran mobile X-ray units in the First World War, and died of marrow failure caused by exposure.