title: Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films.
abstract: The biological uptake of plutonium (Pu) in aquatic ecosystems is of particular concern since it is an alpha-particle emitter with long half-life which can potentially contribute to the exposure of biota and humans. The diffusive gradients in thin films technique is introduced here for in-situ measurements of Pu bioavailability and speciation. A diffusion cell constructed for laboratory experiments with Pu and the newly developed protocol make it possible to simulate the environmental behavior of Pu in model solutions of various chemical compositions. Adjustment of the oxidation states to Pu(IV) and Pu(V) described in this protocol is essential in order to investigate the complex redox chemistry of plutonium in the environment. The calibration of this technique and the results obtained in the laboratory experiments enable to develop a specific DGT device for in-situ Pu measurements in freshwaters. Accelerator-based mass-spectrometry measurements of Pu accumulated by DGTs in a karst spring allowed determining the bioavailability of Pu in a mineral freshwater environment. Application of this protocol for Pu measurements using DGT devices has a large potential to improve our understanding of the speciation and the biological transfer of Pu in aquatic ecosystems.
authors.affiliation: Institute of Radiation Physics, Lausanne University Hospital.
authors.forename: Ruslan
authors.initials: R
authors.lastname: Cusnir
authors.affiliation: Federal Office of Public Health, Bern, Switzerland.
authors.forename: Philipp
authors.initials: P
authors.lastname: Steinmann
authors.affiliation: Laboratory of Ion Beam Physics, ETH Zurich.
authors.forename: Marcus
authors.initials: M
authors.lastname: Christl
authors.affiliation: Institute of Radiation Physics, Lausanne University Hospital.
authors.forename: François
authors.initials: F
authors.lastname: Bochud
authors.affiliation: Institute of Radiation Physics, Lausanne University Hospital; Pascal.Froidevaux@chuv.ch.
authors.forename: Pascal
authors.initials: P
authors.lastname: Froidevaux
mesh_terms: D059001:Aquatic Organisms / Q000378:metabolism*; D001682:Biological Availability; D002138:Calibration; D004058:Diffusion; D017753:Ecosystem; D008956:Models, Chemical; D010084:Oxidation-Reduction; D011005:Plutonium / Q000737:chemistry* / Q000493:pharmacokinetics*; D012996:Solutions
chemical_list: D012996:Solutions; D011005:Plutonium