Methode MS

Activity Name	Methode MS: Application of mass spectrometry for the measurement of low level, long-lived radionuclides
NKS-B Research Area	Measurement Strategy, Technology and Quality Assurance
Project Summary	During the last 50 years, the use of nuclear energy has discharged a large quantity of anthropogenic nuclides into the environment. Uranium, plutonium and radium isotope ratios are known to give source related information. For example, plutonium isotope ratios are known to vary with reactor type, nuclear fuel burn-up time, neutron flux and energy, and for fallout from nuclear detonations, weapon type and yield. These different sources, having characteristic isotope ratios or “fingerprints” can be used to identify local contamination or follow the contamination in the ecosystem. ICP-MS permits ultra low-level measurement of actinide concentrations and isotope ratios that traditional alpha-spectrometry cannot provide, such as 240Pu/239Pu atom ratios) and 236U/235U atom ratios (3-6). In all these examples, atom ratios can be used to identify the origin of contamination, calculate inventories, or follow the migration of contaminated sediments and water. ICP-MS is also a “workhorse”, giving rapid results providing proper radiochemistry prior to analysis. It should not be forgotten that ICP-MS instrumentation, when handled in a proper way, can provide determination of concentrations of several long-lived radioisotopes where radiometric methods no longer are sensitive enough. This opens up for new type of investigations and thus improves our understanding of their behaviour. New understanding means challenges and possibility for new work which is essential when attracting younger scientists and PhD-students. This project aims at gathering research groups in the Nordic countries in order to explore the various auxiliary equipment connected to mass spectrometry instruments. At the different laboratories analysis of the most common radioisotopes (actinides, Tc-99) are performed but with a very different approach depending on auxiliary equipment used (eg. ETV, ultrasonic nebulisers etc). Sharing knowledge and curiosity with fellow scientists and colleagues at meetings is important but the need for work-group structures where also problems (and not only success) are discussed can not be emphasised enough. Objectives: Identify current needs and problems within low-level determination of long-lived radioisotopes by ICP-MS, to perform intercalibration and development and improvement of ICP-MS methods for the measurement of radionuclides and isotope ratios and to develop new methods based on modified separation chemistry applied to new auxiliary equipment. Sub-goals: 1. Identification of current needs and problems in determining long-lived radioisotopes by ICP-MS in close contact with authorities and other stake holders need 2. Development and optimisation ICP-MS methodology for the determination of long-lived radionuclides (actinides and Tc-99) by designing suitable separation methods applied to auxiliary equipment to overcome current problems. 3. Method validation of ICP-MS for long-lived radionuclides including assessment of matrix effects, intercomparison exercises, and quality control with respect to reference materials; 4. Application of the new methods to determine actinide elements in low level environmental samples from areas contaminated by Chernobyl accident, by uranium mining or global fallout with the aim of improving environmental impact assessment.
Lead Organization	Norwegian University of Life Sciences (UMB), Norway
Contact Person	Lindis Skipperud phone number: +47 64965546