The eldest child of scientists Marie and Pierre Curie, Irène grew up showing talent in mathematics and received a rigorous education from her mother and other prominent French scholars as part of a private cooperative of students. She served as a nurse radiographer at battlefield hospitals during World War I, supervising mobile X-ray units and teaching doctors how to locate shrapnel in wounds using radiology. In 1918, she joined her mother at the Radium Institute in Paris, conducting research on the alpha decay of polonium for her doctorate in 1925.
Irène Joliot-Curie died in Paris on 17 March 1956 from acute leukemia linked to her long-term exposure to polonium and X-rays. The annual Prix Joliot-Curie and Irène Joliot-Curie Prize are named in her honour. In 2026, Irène Joliot-Curie was announced as one of 72 historical women in STEM whose names were proposed to be added to the 72 men already celebrated on the Eiffel Tower.
Biography
Early life and education
Irène Curie was born in Paris, France, on 12 September 1897.:141 The first of Marie and Pierre's two daughters, her sister Ève was born in 1904.:68 After they lost their father in April 1906 in a horse-drawn wagon accident,:70 Marie was left to raise them with the help of her father-in-law, Eugene Curie, who had played an active role in their lives since the girls were born. Irène had a close relationship with her grandfather until his death in 1910.:13
As education was important to Marie. she enrolled Irène's education in a school near the Paris Observatory, . as it had a more demanding curriculum than the school close to the family home. In 1906, when Irène showed she was talented in mathematics, her mother chose to change her focus rather than following the normal public school curriculum. Marie therefore joined forces with a number of eminent scholars, including the prominent French physicists Paul Langevin and Jean Perrin, to form "The Cooperative", a private gathering of 10 students — Irène included — who were children of the most distinguished academics in France. Each contributed to educating the children in their respective homes. The curriculum of The Cooperative was diverse and wide-ranging; alongside science the students also studied subjects such as sculpture and Chinese language. They were also granted sufficient time and opportunities to enjoy sports and outdoor activities.:21
Irène and her sister Ève were sent to Poland to spend the summer with their Aunt Bronia (Marie's sister) in 1911. Irène's education was so rigorous that she still had daily German and trigonometry lessons throughout the break.:5–6 In 1912, Marie's health was poor; she spent most of the next year and a half in sanitoriums, entrusting the care of her daughters to a Polish governess.:12 Irène re-entered a more orthodox learning environment, attending high school at the Collège Sévigné in central Paris. From 1914, she attended the Faculty of Science at the Sorbonne to complete a baccalaureate in mathematics and physics but was forced to pause her studies in 1916 as the events of World War I led to new responsibilities for the Curie family.
During the war, Irène took a nursing course and went to work as a nurse radiographer at battlefield hospitals alongside her mother. They supervised 20 mobile X-ray units and set up approximately 200 X-ray centres for injured soldiers.:133After a few months, Irène was left to work alone at a radiological facility in Belgium. She taught doctors how to locate shrapnel in wounds using radiology and became skilled in repairing the equipment herself. She also trained another 150 women in technical skills for X-ray use in the field.:117–118 She moved throughout facilities and battlegrounds including two bombsites, Furnes and Ypres, and Amiens. In 1918, she received the Médaille militaire for her assistance in X-ray facilities in France and Belgium.:89
Irène's radiography work was not without risks. The tuberculosis she suffered during the course of her wartime efforts,:97 remained a health concern over the next two decades. Her heavy exposure to doses of radiation also left her open to the eventual development of other illnesses, such as leukemia, which later contributed to her death.:118
After the war, Irène returned to the Sorbonne in Paris to complete her baccalaureate degree.
In 1921, Irène published her first physics paper.:171 That year, she accompanied her mother and her sister Ève on a trip to the United States during which Marie hoped to obtain a gram of radium to continue her research. In view of her mother's poor health following a heart attack, Irène stepped in to cover some of her assignments, for example by delivering a lecture at Bryn Mawr College, Pennsylvania. On 23 May 1921, on behalf of her mother, she accepted an honorary degree from the University of Pennsylvania.
In early 1925, as she neared the end of her doctorate, Irène Curie was asked to teach the precision laboratory techniques required for radiochemical research to the young chemical engineer Frédéric Joliot (whom she eventually married on 9 October 1926).:89,96 She became a Doctor of Science in March 1925 with a thesis addressing the alpha decay of polonium, an element discovered by her parents and named after Marie's country of birth, Poland.
Irène Curie in May 1921 on accepting an honorary degree at the University of Pennsylvania on behalf of her mother
Atomic research & Nobel Prize: 1930–1937
During the early 1930s, Joliot-Curie and her husband, Frédéric, combined their research efforts on the study of atomic nuclei. In 1932, thanks to their full access to Marie's polonium, they conducted experiments with gamma rays to identify the positron. Though their experiments identified both the positron and the neutron, they failed to interpret the significance of the results and the discoveries were later claimed by Carl David Anderson and James Chadwick respectively.:132–133 That year, Irène took over the title of chef de travaux (head of operations) at the Radium Institute from her mother.:173
In 1933, Joliot-Curie and her husband were the first to calculate accurately the mass of the neutron. The couple continued trying to make a name in the scientific community; in doing so, they developed a new theory based on an experiment in which aluminium was bombarded with alpha rays, leading to their discovery that only protons were detected. Based on the undetectable electron and positron pair, they proposed that the protons changed into neutrons and positrons. Later in October 1933, this new theory was presented to the Seventh Solvay Conference. The Solvay Conferences consisted of prominent scientists in the physics and chemistry community. Irène and her husband presented their theory and results to their fellow scientists, but received criticism of their findings from most of the 45 scientists attending. Fellow scientist Lise Meitner and her colleagues had attempted similar experiments to that of the Joliot-Curies but had not achieved results that would support their findings. Many in the group believed that the Joliot-Curies had rushed or otherwise formed mistaken conclusions.:112–113
In 1934, the couple made a discovery that sealed their place in scientific history. Building on the work of Marie and Pierre Curie, who had isolated naturally occurring radioactive elements, the Joliot-Curies succeeded in transforming one element into another by creating radioactive nitrogen from boron, radioactive isotopes of phosphorus from aluminium, and silicon from magnesium. Irradiating the natural stable isotope of aluminium with alpha particles (i.e. helium nuclei) resulted in an unstable isotope of phosphorus: 27Al + 4He → 30P + 1n. This phosphorus isotope is not found in nature and decays emitting a positron. The discovery is formally known as positron emission or beta decay, where a proton in the radioactive nucleus changes to a neutron and releases a positron and an electron neutrino. As the application of radioactive materials for use in medicine was growing at the time, the discovery allowed radioactive materials to be created quickly, cheaply, and plentifully. The Nobel Prize for chemistry in 1935 brought with it fame and recognition from the scientific community and Joliot-Curie was awarded a professorship at the Faculty of Science at the Sorbonne.
The importance of these scientific successes was somewhat diminished by the death of Marie Curie on 4 July 1934. As a result, Irène took on many of her mother's former responsibilities at the Radium Institute. The Joliot-Curies began pursuing more separate projects: while Frédéric received a posting at the Collège de France, Irène continued working at the Radium Institute and was a professor at the University of Paris.:137 After 1934, Irène suffered increasingly from tuberculosis and often had to take weeks or months of extended rest, although she continued working whenever possible.:138
Irène and Frederic Joliot-Curie in 1935
Nuclear fission contributions: 1938–1955
In 1938, Irène's laboratory research into radium nuclei helped another group of physicists — but she narrowly missed her chance at a second Nobel Prize. As the international scientific community tried to understand what happened when uranium was bombarded with neutrons, Irène read about experiments conducted by Meitner and Otto Hahn, disagreed with them, and decided to conduct continue her own research. Working with the physicist Paul Savitch, she determined that bombarding uranium with neutrons created a lighter element strongly resembling lanthanum, but they stopped short of declaring it lanthanum, as the widely held assumption was that uranium atoms were too heavy for this kind of transformation. As Meitner and Hahn were skeptical of this result, Irène repeated her research, publishing exactly the same results. The German chemist Fritz Strassmann urged Hahn to take Irène's work seriously, and when they repeated their own experiments using Irène's methods, they finally saw what she had seen. Hahn and Strassmann asked Meitner to help explain the mysterious results, and Meitner determined that the uranium had split in two, allowing for the presence of lighter atoms. Hahn ended up receiving a Nobel Prize for the discovery of nuclear fission. When Irène realized how close she had come to fully discovering fission herself, she and Frédéric expressed regret that they had not worked jointly on the experiments. Their former closer research partnership would perhaps have untangled the problem the same way as Meitner, Hahn and Strassmann.:138–139
In 1948, using work on nuclear fission, the Joliot-Curies, along with other scientists, created the first French nuclear reactor. The couple were active in the organization behind the project, the Commissariat à l'énergie atomique (CEA), the French Atomic Energy Commission. Irène was a CEA commissioner while her husband, Frédéric, was its high commissioner. The reactor, Zoé (Zéro énergie Oxyde et Eau lourde) used nuclear fission to generate five kilowatts of power.:120 This was the beginning of nuclear energy as a source of power for France.
In 1949 she officially became director of her mother's Institut Curie which she had supported for many years.:187
Years of working so closely with radioactive materials finally caught up with Joliot-Curie, and she was diagnosed with leukemia. Treatment with antibiotics and a series of operations relieved her suffering temporarily, but her condition deteriorated. She nevertheless continued to work. In 1955, she prepared plans for new physics laboratories at the Orsay Faculty of Sciences, later completed by her husband.
Political views
Anti-fascism, socialism, and communism
The Joliot-Curies were increasingly aware of the growth of the fascist movement during the 1930s and opposed it.:137–138 Frédéric joined the Socialist Party in 1934,:174 and both he and Irène joined the Comité de vigilance des intellectuels antifascistes a year later.:161 In 1936 they actively supported the Republican faction in the Spanish Civil War.:138 While Irène sympathized with socialist and communist movements — which both had a strong history of supporting feminism in Europe — she felt that her responsibility to the Curie family name meant that she could not declare allegiance to any single political party.:141
The Joliot-Curies had continued Pierre and Marie's policy of publishing all their work for the benefit of the global scientific community; however, afraid of the danger that might result should it be developed for military use as Nazi Germany gained power in the late 1930s, they discontinued doing so. On 30 October 1939, they placed all their documentation on nuclear fission in the vaults of the French Academy of Sciences, where it remained until 1949.:156–157
For the 220th anniversary of the Russian Academy of Science, Frédéric and Irène visited Moscow. On their return, they sympathized with their Russian colleagues. Frédéric maintained a close connection with the Communist Party. As a result of his political views, Irène was later detained on Ellis Island during a trip to the United States. She had been invited by the Joint Antifascist Refugee Committee to speak in support of refugees from Spain.:120 In 1953, Irène applied for membership in the American Chemical Society but was denied. While the society provided no explanation for her rejection, it was believed by members of the scientific community that American anti-Communist sentiment was responsible.:193 The Bulletin of Atomic Scientists published a statement of support for Irène the following year, denouncing political interference in scientific inquiry and collaboration.
Feminism
Irène was a passionate member of the feminist movement, especially in regard to science. She continually applied to the French Academy of Sciences, an elite scientific organization, knowing that she would be denied membership. She did so to draw attention to the fact they did not accept women. She was involved in many speaking functions, such as International Women's Day conferences in Europe.:121–122 An active promoter of women's education, she served on the National Committee of the Union of French Women (Comité National de l'Union des Femmes Françaises).
In 1936, Irène, Cécile Brunschvicg and Suzanne Lacore became the first three women to be appointed French ministers by the French prime minister Léon Blum who belonged to the Popular front.:141 Irène was appointed undersecretary of state for scientific research, in which capacity she helped to found the French National Centre for Scientific Research (CNRS).:153 Although she was not particularly keen on a political posting, she accepted the job as "a sacrifice for the feminist cause in France" in order to support women's rights and set an example. She arranged beforehand that she would remain in the position for three months, and then resigned in order to continue her scientific research.:137
Post-World War II advocacy
Irène Joliot-Curie's political advocacy continued after the war. Together with her sister Ève, in 1946 she attended the trial of the Spanish chemist María Teresa Toral who was accused by Franco of supporting the Republicans. Thanks to their support, her sentence was set at two years imprisonment rather the death sentence or a 30-year prison sentence originally called for. In 1948, during a long strike involving coal miners, French newspapers called on families to assist the strikers by temporarily adopting the children of coal miners until the strike was over. The Joliot-Curies responded by adopting and caring for two young girls.:122
Irène Joliot-Curie was a member of the World Peace Council. She advocated for peace and played a major role for the French contingent at the 1948 World Congress of Intellectuals for Peace, which promoted the World Peace movement,:122 and in 1950 she added her signature to the Stockholm Appeal in protest against the use of atomic bombs.:144
Personal life
The Joliot-Curies in the 1940s
Accompanying her mother, sister and husband, Irène spent several summers in Brittany at L'Arcouest near Ploubazlanec, a resort which attracted scientists who discussed the issues of the times. As a result, in the 1930s, it became known as "Sorbonne plage" (Sorbonne Beach). The Joliot-Curie couple were also keen on sports. Together with their colleagues, they took part in everything from swimming to hiking, tennis and gymnastics.
After their marriage, Irène and Frédéric used variations of their surnames for different purposes. For social events, they both used "Joliot", but when Irène signed her scientific papers she continued to sign them as "Irène Curie". When publishing political statements or popular articles, the couple went by "Joliot-Curie". While Frédéric sometimes fretted about which name to use, Irène was largely indifferent to the question and was comfortable with both surnames.:130–131 They had two children, Hélène, born in 1927, and Pierre, born in 1932.:131
During World War II, Frédéric participated in the French Resistance. Although he made plans to help Irène and their children escape to safety in another country, Irène was firm that they would not leave until Hélène had finished final exams for her baccalaureate degree; after the exam was held in a small village in secret, Irène and both children crossed into Switzerland on foot via the Jura mountains on 6 June 1944. Their journey had the good fortune of coinciding with the date of the D Day invasion, meaning that German soldiers were preoccupied elsewhere that day and did not have as much security along the Swiss border.:140–141
In February 1956, during a brief visit to the family's ski chalet in the French Alps, Joliot-Curie began feeling severely ill and returned to Paris, where she was admitted into the hospital at the Radium Institute.:142–143 She was given a diagnosis of leukemia, a cancer largely suspected to have developed from her years working directly with X-rays and radioactive substances. She died on 17 March 1956 at the age of 58. Frédéric's health was also declining, and he died in 1958 from liver disease, which too was said to be the result of overexposure to radiation.:196–197
Joliot-Curie was an atheist and a pacifict. When the French government arranged for a national funeral to be held in her honour, Irène's family asked for the exclusion of religious and military content. Frédéric was also given a national funeral by the French government.:142–143
Irène Joliot-Curie received the 1935 Nobel Prize in Chemistry together with her husband, Frédéric Joliot-Curie, for their discovery of induced radioactivity.:136 They were the second married couple, after her parents, to win the prize, adding to the Curie family's unbeaten legacy of four Nobel Prizes shared among five individuals. (In addition to the three prizes in physics and chemistry held by the Curies and Joliot-Curies, Ève Curie's husband Henry Labouisse went on to receive a Nobel Peace Prize.):405
As of 2026, she and her mother Marie Curie form the only mother–daughter pair to become Nobel laureates, while Pierre and Irène Curie are the only father-daughter pair to have won Nobel Prizes, compared to seven father-son pairs.
Other awards
Irène Curie received the French Médaille militaire (military medal) in 1918 for her work with radiography in World War I.:89
In 1932, she and Frédéric Joliot-Curie were jointly awarded the Italian Matteucci Medal for physicists.
The Prix Joliot-Curie, an annual award recognizing achievements in nuclear physics and particle physics, was named in honour of Joliot-Curie by the Société Française de Physique in 1956. The French government launched the Irène Joliot-Curie Prize, which recognizes women in science, in 2001.
In 2026, Joliot-Curie was announced as one of the 72 historical women in STEM whose names were proposed to be added to the 72 men already celebrated on the Eiffel Tower. Her mother was also on the list. The plan was announced by the Mayor of Paris, Anne Hidalgo following the recommendations of a committee led by Isabelle Vauglin of Femmes & Sciences and Jean-François Martins, representing the operating company which runs the Eiffel Tower.
Selected publications
In 1928, Irène and her husband Frédéric began to conduct research on atomic nuclei. From 1934, they published papers on important new discoveries, including the creation of radioactive isotopes. This led to the Nobel Prize in 1935 and paved the way for further research covering the fission of heavy metals. In 1954, on the occasion of the 20th anniversary of her mother's death, Joliot-Curie was invited by the journal Europe to document her memories and impressions of her mother. It was not published at the time but in 2022 it appeared as a book titled Marie Curie, ma mère.
Curie, I. (1925) Primary thesis: Recherches sur les rayons α du polonium. Oscillation de parcours, vitesse d'émission, pouvoir ionisant. Secondary thesis suggested by the university: La sursaturation des vapeurs
Joliot-Curie, I.; Joliot-Curie, J.F. (1932) La projection de noyaux atomiques par un rayonnement très pénétrant
123456789101112131415161718McGrayne, Sharon Bertsch (1998). Nobel Prize Women in Science: Their Lives, Struggles, and Momentous Discoveries. Washington, DC: Joseph Henry Press. pp.117–143. ISBN978-0-309-07270-0.
12Pigeard-Micault, Natalie (2026). "Irène Curie, épouse Joliot (1897-1956)". Les femmes du laboratoire de Marie Curie[The women of Marie Curie's laboratory] (in French) (2nded.). Paris: Éditions Glyphe. pp.80–88. ISBN978-2-35815-358-4.
↑Pigeard-Micault, Natalie (2013). Les femmes du laboratoire de Marie Curie[The women of Marie Curie's laboratory] (in French) (1sted.). Paris: Éditions Glyphe. pp.201, 212, 220, 232, 252, 257. ISBN978-2-35815-111-5.
↑Bécoulet, Alain (17 February 2022). "The Saga of Nuclear Energy". MIT Press. Archived from the original on 30 April 2026. Retrieved 20 September 2026.
↑"It was to her grandfather, a convinced freethinker, that Irène owed her atheism, later politically expressed as anticlericalism." Joliot-Curie, Irène. Complete Dictionary of Scientific Biography. 2008. Encyclopedia.com. 17 March 2012.
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