Rare Earths ESCo: towards responsible use of rare earths throughout their life cycle: what are the future prospects in terms of sobriety, recycling and production methods?

05 juin 2026

Rare earths are metals that are of crucial interest for France. Their supply is a vital issue on many levels - industrial, technological, geopolitical, economic, environmental and health-related. The Rare Earths Collective Scientific Expertise (ESCo) is a CNRS initiative that aims to establish the state of scientific knowledge on the use of rare earths throughout their life cycle through study of sobriety and recycling practices along with changes to extraction and production methods.

Particular attention is being paid to rare earth elements (REEs) in the current international context of industrial supply being under pressure. Such metals possess unique properties that make them key assets in many fields, including renewable energies, e-mobility, medical imaging or chemical catalysis, to name just a few. Government and industry are currently calling for a new REE strategy for several reasons. On one hand, strong annual growth in demand is leading to increased dependence on primary deposits while on the other, there are of course issues linked to the environmental impact and strong negative externalities associated with their extraction and processing and, finally, to the inherent geopolitical risks of the current situation featuring almost exclusive Chinese production and processing.

The expertise report on rare earths carried out by the CNRS's Mission for Scientific Expertise (MPES) aims to establish the state of current scientific literature on the issues and opportunities linked to more responsible usage of rare earths. The report eschews taking the question of reserves as its starting point and instead will provide a comprehensive multidisciplinary overview of the current and future uses of REEs. It also surveys scientific knowledge in three main areas: 

  1. reducing use, including discussions of possible substitutions of REEs and their usages;
  2. recycling, particularly through 'urban mining';
  3. producing REEs differently by exploring more environmentally-friendly approaches and alternative supply sources like waste from mining of other minerals. 

The ESCo advises whether knowledge of uses of other strategic and critical metals can be transposed to REEs and in which conditions. 

The CNRS ensures the relevant principles of competence, independence, impartiality and transparency are respected in this collective expert scientific review. 

The expertise concluded in the last quarter of 2025 and was carried out by a multidisciplinary collective of scientific experts based on a documentary corpus of several thousand references.

Assessment report

The experts and authors who contributed to this document

Scientific leads

  • Pascale RICARD is a lawyer specialising in international, maritime and environmental law, and a research fellow at the CNRS at the laboratory Droits international, comparé et européen – DICE (Aix-Marseille Université – CNRS).
  • Clément LEVARD is a physical chemist and specialist in environmental geoscience, and a research director at the CNRS at the Centre de Recherche et d'Enseignement des Géosciences de l'Environnement – CEREGE (Aix-Marseille Université – CNRS – INRAE – IRD).
  • Romain GARCIER is a geographer, a specialist in geographical approaches to critical materials and rare earths, and a senior lecturer at the ENS de Lyon, affiliated with the laboratory Environnement Ville Société – EVS (CNRS – ENTPE – ENS de Lyon – ENSA Lyon – Université Jean Monnet – Université Lumière Lyon 2 – Université Lyon 3 Jean Moulin).

Principal experts

  • Kevin BERNOT is a chemist, professor at the Institut National des Sciences Appliquées (INSA) in Rennes at the Institut des sciences chimiques de Rennes – ISCR (CNRS – ENSC Rennes – Université de Rennes).
  • Bénédicte CENKI is a geologist and professor at the Université de Montpellier at the laboratory Géosciences Montpellier (CNRS – Université de Montpellier).
  • Marie FORGET is a geographer and senior lecturer at the Université Savoie Mont Blanc at the laboratory Environnement, Dynamique et Territoires de la Montagne – Edytem (CNRS – Université de Savoie Mont Blanc).
  • Olga FUENTES is a specialist in life cycle analysis with a background in electronic engineering, a junior researcher at the Université de Bordeaux at the Institut des Sciences Moléculaires – ISM (Bordeaux INP – CNRS – Université de Bordeaux), working in partnership with Guido Sonnemann.
  • Laure GIAMBERINI is an ecotoxicologist, professor of exceptional rank at the Université de Lorraine and director of the Laboratoire interdisciplinaire des environnements continentaux – LIEC (CNRS – Université de Lorraine).
  • Émilie JANOTS is a geologist and senior lecturer at the Université Grenoble-Alpes at the Institut des Sciences de la Terre – ISTerre (CNRS – IRD – Université Grenoble Alpes – Université Savoie Montblanc).
  • Brice LAURENT is a sociologist and researcher at Mines Paris-PSL at the Institut interdisciplinaire de l’innovation-I3 (CNRS – École Polytechnique – Mines Paris-PSL – Télécom Paris). He is also director of the Direction Sciences Sociales, Économie et Société de l’Anses.
  • Gilles LHUILIER is a lawyer, professor of private law at the ENS de Rennes, and a senior member of the Institut Universitaire de France.
  • Frédéric MAZALEYRAT is a physicist and professor at the ENS Paris-Saclay in the laboratory – Systèmes et applications des technologies de l'information et de l'énergie – Satie (CNAM – CNRS – CY Cergy Paris Université – ENS Paris-Saclay – Université Paris-Saclay).
  • Stéphane PELLET-ROSTAING is a chemist and CNRS research director at the Institut de chimie séparative de Marcoule-ICSM (CEA – CNRS – ENSC Montpellier – Université de Montpellier).
  • Guido SONNEMANN is a chemist and specialist in life cycle analysis, and a professor at the Université de Bordeaux at the Institut des Sciences Moléculaires – ISM (Bordeaux INP – CNRS – Université de Bordeaux).
  • Eric VAN HULLEBUSCH is a biogeochemist and professor at the Institut de physique du globe de Paris – IPGP/IPGP-UMR (CNRS – IPGP-Université Paris Cité).
  • Fanny VERRAX is a philosopher and associate professor of ecological transition and social entrepreneurship at EmLyon Business School.
  • Alexandre VIOLLE is a sociologist and junior researcher at Mines Paris-PSL at the Institut interdisciplinaire de l’innovation – I3 (CNRS – Ecole Polytechnique – Mines Paris-PSL – Télécom Paris), working in partnership with Brice Laurent.

 

Contributing experts 

  • Yacine AMARA is a physicist and a lecturer at the Université de Le Havre Normandy within the Groupe de Recherche en Électrotechnique et Automatique du Havre – GREAH (Université Le Havre Normandie).
  • Valentin BAUDOUIN is a lawyer and researcher at the Centre européen de recherche sur le risque, le droit des accidents collectifs et des catastrophes – CERDACC (Université de Haute-Alsace).
  • Laurent CALVEZ is a chemist and professor at the Université de Rennes within the Institut des Sciences Chimiques de Rennes – ISCR (CNRS – ENSC Rennes – Université de Rennes – INSA Rennes).
  • Laurent CASSAYRE is a chemist and research director at the Laboratoire de Génie Chimique – LGC (CNRS – Toulouse INP – Université de Toulouse).
  • Florian JAROSCHIK is a chemist and researcher at the Institut Charles Gerhardt Montpellier –  ICGM (CNRS – ENSC Montpellier – Université de Montpellier).
  • Elsa LAFAYE DE MICHEAUX is an economist and professor at the Université de Rennes 2 in the Centre Asie du Sud-Est – CASE (CNRS – EHESS – INALCO).
  • Alexandra LANGLAIS is a lawyer and researcher at the Institut de l'Ouest : Droit et Europe – IODE (CNRS – Université Rennes).
  • Florian LEBLANC is an economist and research engineer at the International Centre international de recherche sur l'environnement et le développement – CIRED (AgroParisTech, Université Paris-Saclay, CIRAD, CNRS, EHESS, ENPC, Institut Polytechnique de Paris).
  • Louis-Marie MALBEC is an engineer and economist, and a researcher at IFP Energies nouvelles – IFPEN.
  • Alexander STINGL is a sociologist and researcher at the School of Political Science & Sociology (University of Galway). 
  • Luca TENREIRA is a lawyer and a researcher at the European University Institute. 
  • Raphaël TRIPIER is a chemist and professor at the Université de Bretagne Occidentale in the laboratory Chimie, Électrochimie Moléculaires et Chimie Analytique – CEMCA (CNRS – Université Bretagne Occidentale EPE, Brest).
  • Francesco RICCI is an economist and professor at the Université de Montpellier in the Centre d'Economie de l'Environnement de Montpellier – CEE-M (CNRS – INRAE – Institut Agro de Montpellier – Université de Montpellier).

Photo credit : © Cyril FRESILLON / Mecaware / CNRS Images