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Enhancing Nuclear Safety



Scientific News


Research Programs
Hydrogen risk: MITHYGENE project extended for a further three years
The MITHYGENE project, which aims to improve our understanding of how to manage the hydrogen risk – i.e. the risk that the hydrogen produced during a PWR core meltdown may explode - has been extended for a further three years, up to 2021. This industrial phase gathers researchers and engineers from IRSN, CEA-LIST and Arcys.
The project has been extended in order to move on from the lab prototype developed during the second phase (2016-2018) to producing the first industrial measurement prototype. This system will provide real-time information on the composition of the atmosphere inside the reactor containment, and particularly on the concentrations of hydrogen in the reactor containment, during severe accident conditions.
Launched by IRSN in early October 2013 and funded under France's 'Investment in the Future' program, MITHYGENE is focused on improving our understanding of the phenomena governing the hydrogen risk and on developing prototype instrumentation for measuring gas concentrations suitable for use under the conditions produced in the reactor containment during a severe accident. Advances made on the project are being used to improve severe accident management procedures and will also be used in explaining the events that occurred during the accident at Fukushima-Daiichi in 2011. The findings of the project should also help improve the practices adopted by industry operators to eliminate the risk of hydrogen explosion at their own facilities, be they nuclear or non-nuclear.
The objectives of the first two phases in the MITHYGENE project were to improve the predictability of computer codes used to assess the risk of hydrogen explosion and to develop real-time in situ instrumentation for measuring gases, qualified for severe accident conditions. That involved performing experimental research on hydrogen distribution in the containment as well as on hydrogen flame propagation and the resistance of reactor structures and systems to withstand hydrogen gas combustion. The results obtained have proven pertinent in explaining the sequence of accidents that occurred at Fukushima-Daiichi. These results are now being used to plan industrialization of the prototype, the reason for this extension, which has just recently been launched.

Find out more about MITHYGENE project


IRSN's theses days 2019


Logo-JT2019.jpgIRSN's theses days 2019 will start on Monday, April 1st until Thursday, April 4th and will take place in La Grande-Motte (France). This seminar, which takes place every year, is a unique event for the IRSN PhD students to exchange and meet.

Theses days allow 2nd and 3rd years PhD students to present their work in front of their colleagues from the institute and from different research organizations (universities, industries…). The 1st year PhD students will present their thesis work through poster sessions. During theses days, for the first time, one of these PhD students will be rewarded for its poster.


This year, the third IRSN's "3 minutes thesis" contest will be held: 12 PhD students will present their thesis projects in 3 minutes each, in the clearest and most attractive way possible. The last contest has taken place in 2017 and was won by Sabine Hoffmann, for her presentation "Incertitude d'exposition dans les études épidémiologiques" (Uncertainty of exposure in epidemiological studies).


Find out more about theses at IRSN
Find out more about IRSN's 3 minutes thesis" contest (in French)


Postdoctoral scholar Nagore Grijalba awarded at the EWCPS 2019


Nagore Grijalba, a postdoctoral scholar at IRSN’s Radiochemistry, Speciation and Imaging Laboratory (LRSI), won an award for the poster that she presented at the 18th European Winter Conference on Plasma Spectrochemistry (EWCPS 2019), which took place on February 3-8, 2019 in Pau.

Prix_Nagore_Grijalba.jpgThe postdoctoral scholar received the Poster Prize of Innovative Analytical Research for her poster on the “Development of a new methodology for mapping and quantifying uranium in the kidney using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)”. More than 300 posters were in the running.

Her postdoctoral work, which started in summer 2018 for 18 months, aims to develop a method for analyzing the distribution of uranium in the kidney using a technique that combines laser ablation with inductively coupled plasma mass spectrometry (ICP-MS) 1. Very few studies have been published to date on the use of this technique for the micro-quantification of uranium in renal tissue. The results were compared with those already obtained using secondary ion mass spectrometry (SIMS) 2 in order to evaluate the performance of each technique with regard to sensitivity and lateral resolution.

The research is carried out in the LRSI, which has been working for several years on the micro-distribution of uranium in biological tissue. The lab has developed a type of analysis based on the SIMS technique to “micro-locate” the sites where stable or radioactive elements accumulate in the tissue. This type of analysis has shown that, after chronic contamination by ingestion, uranium is most likely to accumulate in the renal cortex and in cell nuclei. The technique cannot, however, be used to quantify uranium in affected kidney substructures, such as the proximal convoluted tubules. The work of Nagore Grijalba as part of the Uranium Kidney CANcer (UKCAN) project, co-funded by Orano, should provide essential additional information on the micro-location and micro-quantification of uranium at the renal tissue level in rodents.

In cooperation with IRSN’s Experimental Radiotoxicology and Radiobiology Laboratory (LRTOX), these developments should make it possible to establish a correlation between the distribution of uranium and the biological effects observed in order to improve knowledge of the mechanisms that prefigure the renal toxicity of uranium. Furthermore, the data obtained on the location and quantification of uranium at the renal tissue level should make it possible to quantify the radiological dose as realistically as possible, not for the kidney as a whole but for the affected kidney structure, in association with IRSN’s Internal Dose Assessment Laboratory (LEDI).

  1. Inductively coupled plasma mass spectrometry, or ICP-MS, is a type of mass spectrometry capable of detecting very low concentrations of metals and several non-metals.

  2. Secondary ion mass spectrometry, or SIMS, is a surface analysis method that consists in bombarding the surface of the sample to be analyzed with an ion beam.

Photo: Nagore Grijalba during EWCPS 2019. © IRSN

​​ ​Find out more about the Rad​iochemistry, Speciation and ImagingLaboratory (LRSI)


The 18th issue of Aktis, IRSN’s scientific newsletter, is available

Aktis-18-EN.jpgThe eighteen English-language issue of Aktis, the quarterly newsletter on IRSN’s research, is available on a HTML and PDF package. Aktis is published only in a digital version and available in HTML or text format for e-mail, RSS and pageflip PDF.


In this issue, focus on aging the concrete in geological disposal of radioactive waste. Aktis n°18​ also treats of an analysis of the Fukushima Daiichi accident for IRSN's simulation tools. As well, it deals with assessment of alpha therapy doses.​


The subscription for the English and French versions is complimentary. To read this issue or subscribe, go to​​.


Read the pageflip PDF​​​​​

Read the HTML page



Research programs

Two days dedicated to post accident management as part of TERRITORIES


The IRSN has jointly organized, with the CLIN of Le Blayais and the Nuclear Protection Assessment Research Center (CEPN), a workshop on the management of regions after a nuclear accident. This event took place on December 11 and 12, 2018, at the Gironde (Bordeaux) Departmental Council as part of the European research project TERRITORIES. This aims to draw up an integrated and graduated method for reducing uncertainty during decision-making processes for the long-term management of contaminated regions, in a way which involves all stakeholders.


Atelier-TERRITORIES.jpgThis workshop is part of one of the main lines of the TERRITORIES project (work package 3) focusing on the involvement of stakeholders and taking account of their expectations in decision-making processes in the various situations regarding long-term exposure to radionuclides. It is part of a series of three events taking place in parallel in France, Spain and Belgium, with a view to comparing member states.


The first day has enabled actors in the region to talk to their counterparts from Japan and Belarus involved in the clean-up after the Fukushima-Daiichi and Chernobyl accidents. The reports mainly related to the difficulties and challenges for agriculture in how it deals with the long-term consequences of the post-accident situation. They presented their experiences of the remedial measures taken in the sector and the conditions and difficulties with regard to the resumption of agricultural activities after an accident. The second day, with a smaller committee and a panel of local stakeholders, looked into the medium- and long-term challenges and the socio-economic uncertainties facing these stakeholders, in light of their local knowledge.


The TERRITORIES European project, launched in 2017 as part of CONCERT for three years and headed by the IRSN, aims to build a method for managing risk linked to long-term exposure in contaminated areas after a nuclear accident or from old mines (increased natural radioactivity). The project aims to reduce uncertainties associated with, on the one hand, the evaluation of doses absorbed by the human population and wild animals, and on the other hand, decision-making processes, taking into account the involvement of all stakeholders (institutional structures, experts, associations, citizens, etc.). The program involves 11 partners from 8 European countries.


Various types of long-term contamination situations are looked at, including those related to increased natural levels of radioactivity and post-accident situations. The IRSN is involved in various case studies to estimate the radioactive exposure of populations (e.g. participative science approach in a Belarusian village located near the Chernobyl exclusion zone). The IRSN is also working on how stakeholders take account of uncertainties in decision-making processes. Notably, in 2019 the Institute will contribute to the technical guides and will coordinate two final guides focusing on the long-term management of radioactive regions for each of the contamination scenarios.


 Know more about the TERRITORIES project

 Workshop schedule (in French)

 Contact: Sylvie Charron or Marie Simon-Cornu


Photo: TERRITORIES workshop © IRSN




4th IRBA Symposium on Radiobiology: Best Poster Award for Frédéric Soysouvanh 


Frédéric Soysouvanh, PhD student at the Radiobiology of Medical Exposure Laboratory (LRMed) of IRSN, received a Best Poster Award from the Armed Forces Biomedical Research Institute (IRBA) during its 4th radiobiology symposium, held November 6 and 7 in Paris.


His poster, titled Ionizing radiation-induced endothelial senescence and role in normal tissue injury, covered his thesis on "radiation-induced endothelial senescence and its effects on radiation damage to healthy tissue". In the frame of exposition to ionizing radiation during radiation therapy, this research targets the vascular endothelium (monolayer of cells lining the inside of blood vessels). It aims to better understand the molecular pathways behind their senescence, i.e. when cells lose ability to proliferate. Frédéric Soysouvanh seeks to find the link between the underlying molecular pathways and the chronic pathological dysfunction of the vascular system that was damaged by ionizing radiation. He works on preclinical in vivo models.


The IRBA, which awarded him its prize, is the Armed Forces Health Service (SSA), an institute specifically dedicated to research and that conducts biomedical research focused particularly on CBRN (chemical, biological, radiological and nuclear) defense for active military personnel. For the past four years, this institute has been organizing a symposium on radiobiology, whose goal is to present the latest research in the biomedicine field addressing defense issues.


 Know more about Frédéric Soysouvanh's thesis



Radiation protection training

Five-day training about dosimetry uncertainty in April 2019


logo_concert.jpg The French Institute for Radiation Protection and Nuclear Safety (the "IRSN") is co-organizing a training course on "Uncertainty in biological, physical and internal dosimetry following a single exposure", to be held at IRSN (Fontenay-aux-Roses, France) from April 15th to April 19th, 2019.


Organized in the framework of EURADOS network and funded by the European research program CONCERT, this training course is intended to provide a detailed description of statistical methods used to deal with uncertainty in biological, physical and internal dosimetry following a single exposure to ionizing radiation.

This course is mainly open to MSc/PhD students and other young scientists who want to gain knowledge of the standard and more advanced methods (i.e. including mathematical, probabilistic and statistical concepts) used to identify, characterize, describe/model and estimate the main sources of uncertainty associated with dose estimation in retrospective dosimetry. The course is also intended for later career professionals who want to deepen their knowledge in this field.

This training program is organized in partnership between IRSN, the European EURADOS network, Public Health England (PHE, UK), the German Federal Office For Radiation Protection (BfS, Germany) and the Autonomous University of Barcelona (UAB, Spain). The course will be given in English. A maximum of 20 participants will be accepted. The application deadline has been set for February 15th, 2019.


 Flyer, including application details

 Apply by email to Sophie Ancelet

 Know more about CONCERT

 Know more about EURADOS




A formal Chancellerie prize for Marie Kerveillant



Marie Kerveillant, who defended her thesis in management sciences in April 2017, has won one of the Aguirre-Basualdo prizes in Economics and Management, awarded by the Chancellerie des universités de Paris. She received her award during an official ceremony on December 4th at the Sorbonne in Paris.


Prix-Marie-Kerveillant.jpgThe prize was awarded for work detailed in her thesis on the role of the public in the governance of nuclear risks. She was particularly interested in the ways local organizations in civil society, in particular Commissions of Local Informations (CLI), participate in the governance of nuclear risks in France. She studied the case of CLIs in the Cotentin peninsula in northern France. Her work was conducted at the ESSEC Business School under the auspices of the EM2P postgraduate school in Cergy-Pontoise, within the framework of a partnership between the ESSEC and the IRSN (Human and Social Sciences Laboratory - LSHS).


This prize is one of fifty consequential awards of 10,000 Euros awarded by the Chancellerie des universités de Paris to young doctoral graduates in the Paris region, in all disciplines (law, political science, medicine, literature, humanities, economics, etc.) for thesis work which has advanced research in their disciplines in a remarkable way. The Chancellerie also awarded six thesis prizes of € 2,000 in 2018, along with twelve honorary prizes. Distinctions are attributed by juries, each composed each of three notables, either university professors, members of one of the great state institutions, or of the Institut de France.


 Know more about Marie Kerveillant's thesis

 Know more about Chancellerie prizes


Photo: Marie Kerveillant receiving her award © IRSN




Recruitment for PhD proposals at the IRSN laboratories for the 2019 academic year has started ! 


To benefit from a thesis financing, you must hold a Master's degree or an equivalent diploma allowing enrollment in a doctoral school, before the month of October of the current year. In the case of diploma equivalence, the authorization of registration with the doctoral school associated with the subject will have to be verified before the assembly of the application file. Unless waived, you must be under 26 years old when you apply and have graduated with honors.
Additional information on the thesis (description, tutor name, research unit, etc.) are also available by clicking on the subject.The first step to apply is to contact the tutor of the thesis (mail address: by sending CV and application letter. If your profile interests him, he will tell you the rest of the process. ​
The final selection of topics and candidates will take place in May-June 2019.

​ Proposals list


Experimental facilities

Inaugural irradiations with the MIRCOM microbeam


First irradiation run for the MIRCOM system, which received the go-ahead in mid-October from French Nuclear Safety Authority (the "ASN"). These initial "shots" at cells will allow final specification of microbeam characteristics.


MIRCOM_pilotage-microfaisceau.jpgThe MIRCOM system, which recently received its operating license from the ASN, has been conducting its first cell irradiation run last week. In connection with the radiobiologists from the Radiobiology & Regenerative Medicine Department (the "SERAMED") of the French Nuclear Safety & Radiation Protection Institute (the "IRSN"), this operation will identify the microbeam characteristics, i.e. estimation of the size of the ion beam targeting the cells and measurement of the shooting accuracy of the system. Once the characteristics are determined, the microbeam will be ready for use in IRSN radiobiology experiments, such as those conducted under the ROSIRIS program to better understand the side-effects of radiation therapy. In practice, MIRCOM is capable of targeting cellular and subcellular parts with a defined number of ions and with micrometer precision.


MIRCOM uses the 2MV Tandetron accelerator, originally installed for the AMANDE system. Since 2005, it has been the national standard for metrology for neutrons in monoenergetic fields. The MIRCOM system is open to research teams from the national and international scientific communities (especially European), in the context of research programs for radiation protection.



Further informations

The MIRCOM microbeam (coming soon)



Photo: View of the end of the microbeam line, with François Vianna-Legros, engineer-researcher at the LMDN, in front of the AMANDE accelerator control station © IRSN




Jacques Dalla Torre award granted to Paul Eyméoud


Paul Eyméoud, a PhD student at IRSN's Material Physics and Thermal-Mechanics Laboratory (LPTM), received the 2018 Jacques Dalla Torre award on November 21 from the French Society for Metallurgy and Materials (SF2M) at the 2018 Materials Conference held in Strasbourg from November 19 to 23. This award has been presented each year since 2006 to a young materials physicist in the field of modeling.


Prix-Eymeoud.jpgCurrently in his third year of doctoral studies, Paul Eyméoud was recognized for his work on atomistic modeling of nuclear cladding embrittlement by hydrides in pressurized water reactors. The zirconium alloys used for fuel rod cladding oxidize on its surface. The released hydrogen migrates and is absorbed in the metal core of the cladding. When the hydrogen concentration reaches the solubility limit, the excess hydrogen forms hydride precipitates in the metal, which embrittles the material. Paul Eyméoud has developed an innovative energy calculation model revealing an unusual range of interactions between atoms in cladding: the most significant interactions do not occur between neighboring atoms but between atoms that are more distant from each other. This model will provide a better understanding of the phenomenon of hydride precipitation and its impact in terms of thermomechanical stresses generated in the cladding.


This prize will allow Paul Eyméoud to supplement his training in ab initio electronic structure calculations thanks to a one-month stay at the Institute of Condensed Matter and Nanoscience (Université catholique de Louvain, Belgium) in the nanoscopic physics department led by Xavier Gonze.


Further informations

Know more about Paul Eyméoud's thesis  

Know about ICMN

Know more about SF2M

Know more about the 2018 Materials Conference


Photo: Paul Eyméoud receiving his award © SF2M




HEIR Conference: An Award for Manon Jacquemin



Manon Jacquemin, a doctoral student at LEDI (Internal Dose Assessment Laboratory), won first place among the presentations given by young researchers at the HEIR Conference which took place from October 8 to 11 in Fontenay-aux-Roses.


Prix-HEIR-Jacquemin.jpgThe award recognized her presentation of her thesis work on dosimetry for radiolabeled cells (beta-plus emitters) to monitor their location in vivo using positron emission tomography (PET) imaging. The radiolabeled cells are used in diagnostic nuclear medicine (radiopharmaceuticals). For example, radiolabeled blood cells can detect the presence of inflammatory sites in the organism and radiolabeling can be used to monitor the migration of stem cells in the case of cellular therapy. However, radiolabeling does have limitations, some of which are related to the method of cell incubation: functional alterations in the cell or cell death. Manon Jacquemin is working to assess the precise doses received by cells during radiolabeling and to correlate them with the effects radioactivity produces in them, including viability, proliferation, clonogenicity*, etc.


The prize was awarded by a jury of six people and sponsored by The European structure MELODI, which lent financial support to the conference. Twelve young researchers were in the running and three distinctions were handed out according to three criteria: summary, abstract and quality of the oral presentation.


The International Conference on the Health Effects of Incorporated Radionuclides (HEIR) was co-organized by IRSN and the CEA to focus on the latest advances in fields relating to the study of incorporated radionuclides.


* Cell capacity for rapid growth


Further informations

 Know more about Manon Jacquemin's thesis

 Know more about LEDI


Photo: on the right, Manon Jacquemin © IRSN




SFRO conference: a Best Poster Award for Alexia Lapière


Alexia Lapière, a doctoral student at IRSN's LRMed* (Radiobiology of Medical Exposure Laboratory) won a best poster prize at the 29th conference of the French Society for Oncological Radiotherapy (SFRO) which took place October 4 to 6 at La Défense (France).


She was one of three people singled out from the 90 physicians, interns and doctoral students who presented a poster at the conference. Her poster related to her thesis work on "the effect of Faecalibacterium Prausnitzii Treatment on Radiation-induced Colonic Lesions – Application for Treating Complications after Pelvic Radiation Therapy". She is studying effects of a probiotic, called Faecalibacterium prausnitzii, on the delayed onset colonic lesions, which can occur up to 10 years after the end of a pelvic radiation therapy. This research, carried out in collaboration with INRA, aims to assess the efficiency of this probiotic administered preventively, before radiation therapy begins, to reduce lesions in healthy tissue (around the tumor). Its effectiveness has already been proved in pre-clinical studies to treat other inflammatory pathologies of the colon.


The French Society for Oncological Radiotherapy, created in 1990, includes nearly all practicing French radiation therapists, as well as doctors, physicists and biologists whose main work is oncology and radiation therapy.

* At SERAMED (Department for Research in Radiobiology and Regenerative Medicine) under the Environment health Cluster, Health Division.

Further informations

 Know more about Alexia Lapière's thesis

 Know more about LRMed

 Know more about the 2018 SFRO conference

 Contact: Alexandra Semont




12th International Conference on the Health Effects on Incorporated Radionuclides (HEIR) 



logo_HEIR_2.jpgHEIR 2018, the 12th International Conference on the Health Effects of Incorporated Radionuclides, opens Monday, October 8 at the IRSN headquarters in Fontenay-aux-Roses, France, and runs until October 11, 2018. The conference has been co-organized by the IRSN (French Institute for Radiological Protection and Nuclear Safety) and the CEA (French Alternative Energies and Atomic Energy Commission). It has been held in the IRSN's new auditorium and 120 delegates are set to attend.


The conference is an opportunity to discuss the latest advances in every field of incorporated radionuclides. Topics addressed will include biokinetics, chemistry of radionuclides, dosimetry of internal contamination, radiotoxicology, and radiobiology, as well as radionuclide applications in nuclear medicine (e.g. medical imaging and therapy). The organizing committee comprises representatives of both the IRSN and the CEA, two leading bodies in radiation toxicology and radiation biology research. The committee is co-chaired by J-M. Bertho (IRSN) and F. Menetrier (CEA).

Further informations

 HEIR 2018 website

 11th HEIR conference 



​Research applications
Skin contamination by radionuclides: the first emergency treatment is on the market
Since July 2018, Cevidra has marketed Cevidra® Calixarene, the first emergency local treatment for skin contamination by actinides (such as uranium, plutonium, americium, etc.). The treatment, a simple-to-use cleansing cream, prevents uranium from passing through the skin barrier by more than 95% if applied immediately, and was developed during two theses in IRSN's Radiochemistry, Speciation and Imaging Research Laboratory (LRSI) in partnership with the Institut Galien Paris-Sud (UMR CNRS 8612) and the Defense Procurement Agency (DGA). Presented in preview at the World Nuclear Exhibition in Paris (26-28 June 2018), an international nuclear event, this cream earned Cevidra the "Nuclear Safety" WNE Award in the SMEs category.


Previously, the only treatment available was an emergency rinsing with soapy water, which was not very effective. This cleansing cream consists of a nanoemulsion with the active ingredient calixarene carboxylic acid (1,3,5-OCH3-2,4,6-OCH2COOH-p-tertbutylcalix[6]arene), which traps actinides, notably uranium. It therefore prevents them from passing into the bloodstream, where they can become attached to the kidneys and bones, causing a risk of pathologies developing in these organs over time. The marketing of the cleansing cream is the culmination of 10 years of research by the LRSI and the Institut Galien Paris Sud.


Read more


Post-doctorate proposal at Radiobiology of medical exposure laboratory (LRMed)
The LRMed is recruiting a postdoctoral researcher for an 18 months contract starting in January 2019 to work on the "Impact of mitochondrial metabolism on tumorigenesis, tumor-derived angiogenesis and cancer cell response to radiotherapy".


Post-doctorate contracts give doctoral graduates an opportunity to develop their competence while contributing to IRSN’s research work. The recruitment procedure for this programme is similar to that established for doctoral theses, in that candidates’ proposals for research projects are reviewed by researchers from universities or other research institutes.


See the post-doctorate proposals page
The 17th issue of Aktis, IRSN’s scientific newsletter, is available

The seventeenth English-language issue of Aktis, the quarterly newsletter on IRSN’s research, is available on a HTML and PDF package. Aktis is published only in a digital version and available in HTML or text format for e-mail, RSS and pageflip PDF.


In this issue, focus on simulating the early effects of alpha or proton radiation on DNA. Aktis n°17​ also treats of an epidemiological study on a population of Russian children on the possible link between cardiac arrhythmias and low doses of cesium-137. As well, it deals with P²REMICS, state-of-the-art models and original numerical schemes to simulate deflagration.​


The subscription for the English and French versions is complimentary. To read this issue or subscribe, go to​​.


Read the pageflip PDF​​​​​

Read the HTML page

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