Bioscience and Biotechnology Institute of Aix-Marseille
Radio pollution control
Difficult to clean up, the radioactive elements strontium 90 and radium 226 could be extracted from the environment using photosynthetic bacteria capable of selectively trapping them. Coordinated by the Institute of Mineralogy, Material Physics and Cosmochemistry (Sorbonne University) this study was carried out in collaboration with BIAM.
Having contributed to the creation of limestone rocks over geological time, cyanobacteria fascinate evolutionary specialists who seek to understand their capacity to mineralize certain elements of the alkaline earth family (calcium, but also barium, strontium and radium) . Among these, the researchers discovered that Gloeomargarita lithophora is capable of preferentially trapping strontium (Sr), then barium (Ba), even in the presence of an excess of calcium (Ca) yet having similar chemical properties. . In collaboration with BIAM teams, they tested the ability of this bacterium to trap 90Sr and 226Ra, radioactive and toxic isotopes, which can pose a problem in water in the event of environmental contamination. In both cases, the trace radioelement was completely incorporated by the cells even in the presence of a large excess of Ca.
Experiments have shown that cells which have accumulated a significant amount of 90Sr retain their trapping capacity. These experiments pave the way for an application to use this cyanobacterium to decontaminate 90Sr and 226Ra from environmental waters or radioactive effluents. As cyanobacteria develops by photosynthesis, the process could be implemented in open tanks or in photobioreactors.
Neha Mehta, Karim Benzerara, Benjamin Kocar, Virginie Chapon. Sequestration of Radionuclides Radium-226 and Strontium-90 by Cyanobacteria Forming Intracellular Calcium Carbonates. Environmental Science & Technology, American Chemical Society, 2019, 53 (21), pp. 12639-12647. ⟨10.1021 / acs.est.9b03982⟩⟨cea-02374665⟩ (Open Access article)
CEA is a French government-funded technological research organisation in four main areas: low-carbon energies, defense and security, information technologies and health technologies. A prominent player in the European Research Area, it is involved in setting up collaborative projects with many partners around the world.