ResearchResearch projects
Nukleare Umweltforensik mit Radiocäsiumisotopen

Nuclear environmental forensics of radiocesium isotopes

Team:  Dorian Zok, Prof. Dr. Georg Steinhauser, Felix Stäger
Year:  2019
Funding:  Deutsche Forschungsgemeinschaft, Projektnummer 419819104
Duration:  01.01.2019 – 31.12.2021

About the project

If an environmental sample is contaminated with radioactive material (specifically: radiocesium) from several sources, it is difficult to identify the sources of contamination. Using the characteristic 135Cs/137Cs fingerprint, environmental samples should be assigned to a specific source. 135Cs is one of the "most difficult" radionuclides in nuclear environmental analysis and should now be made analytically "detectable". An example of this are the microspheres released in Fukushima, which represent a microscopic archive of fission products from a specific source. Therefore the isotopic composition of the radiocesium fraction in the microspheres will be analyzed by laser ablation triple quadrupole ICP mass spectrometry (LA-ICP-QQQ-MS).

The main topic ist the separation of caesium from aqueous matrices. Therefore, interfering elements such as barium needs to be removed.  In the process, water from the Japanese prefecture of Fukushima will be investigated. Furthermore, laser ablation will be used as an alternative sample delivery system to obtain spatially resolved information from microspheres. For this purpose the extraction of microspheres from contaminated soils and air filters of Fukushima will be performed. Additionally, an overview of different 135Cs/137Cs ratios of different radiologically interesting sites will be prepared. The measurement results of the ICP-QQQ shall be validated by a method comparison with instrumental neutron activation analysis.

The project aims at developing a methodology for (forensic) environmental issues in Germany, based on current questions from Fukushima, which can be used for repository research or for the decommissioning of nuclear facilities (e.g. to identify the cause of contamination).

Cooporation

Atominstitut of the TU Wien