Petrology, geochemistry (Mineralogy) Environmental mineralogy – Understanding element behavior in ecosystems Mine ´ralogie environnementale : comprendre le comportement des e ´le ´ments dans les e ´cosyste `mes Gordon E. Brown Jr. a,b, *, Georges Calas c a Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115, USA b Department of Photon Science and Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA c Institut de mine ´ralogie et de physique des milieux condense ´s (IMPMC), universite ´ Paris-6; universite ´ Paris-7, IPGP, CNRS, case 115, 75252 Paris, France C. R. Geoscience 343 (2011) 90–112 ARTICLE INFO Article history: Received 8 December 2010 Accepted after revision 12 January 2011 Available online 3 March 2011 Written on invitation of the Editorial Board Keywords: Mineralogy Environmental sciences Geochemistry Pollution Toxic elements Surface science Synchrotron radiation ABSTRACT Environmental Mineralogy has developed over the past decade in response to the recognition that minerals are linked in many important ways with the global ecosystem. Minerals are the main repositories of the chemical elements in Earth’s crust and thus are the main sources of elements needed for the development of civilization, contaminant and pollutant elements that impact global and local ecosystems, and elements that are essential plant nutrients. These elements are released from minerals through natural processes, such as chemical weathering, and anthropogenic activities, such as mining and energy production, agriculture and industrial activities, and careless waste disposal. Minerals also play key roles in the biogeochemical cycling of the elements, sequestering elements and releasing them as the primary minerals in crustal rocks undergo various structural and compositional transformations in response to physical, chemical, and biological processes that produce secondary minerals and soils. These processes have resulted in the release of toxic elements such as arsenic in groundwater aquifers, which is having a major impact on the health of millions of people in South and Southeast Asia. The interfaces between mineral surfaces and aqueous solutions are the locations of most chemical reactions that control the composition of the natural environment, including the composition of natural waters. The nuclear fuel cycle, from uranium mining to the disposition of high-level nuclear waste, is also intimately related to minerals. A fundamental understanding of these processes requires molecular-scale information about minerals, their bulk structures and properties such as solubility, their surfaces, and their interactions with aqueous solutions, atmospheric and soil gases, natural organic matter, and biological organisms. Gaining this understanding is further complicated by the presence of natural, incidental, and manufactured nanoparticles in the environment, which are becoming increasingly important due to the rapidly developing field of nanotechnology. As a result of this complexity, Environmental Mineralogy requires the use of the most modern molecular-scale analytical and theoretical methods and overlaps substantially with closely related fields such as Environmental Sciences, low-temperature Geochemistry, and Geomicrobiology. This paper provides brief overviews of the above topics and discusses the complexity of minerals, natural vs. anthropogenic inputs of elements and pollutants into the biosphere, the role of minerals in the biogeochemical * Corresponding author. E-mail address: gordon.brown@stanford.edu (G.E. Brown Jr.). Contents lists available at ScienceDirect Comptes Rendus Geoscience www.sciencedirect.com 1631-0713/$ – see front matter ß 2011 Acade ´ mie des sciences. Published by Elsevier Masson SAS. All rights reserved. doi:10.1016/j.crte.2010.12.005