Within the framework of the European Atomic Energy Community (Euratom) Treaty and derived European legislation, Member States of the European Union are obliged to perform measurements of the radioactivity levels in their environment.
The results of this monitoring shall be reported to the European Commission . The Radioactivity Environmental Monitoring (REM) group of the JRC collects, validates and publishes the reported data.
Since 2003, the JRC in Geel is organising proficiency testing (PT) exercises for European radioactivity monitoring laboratories. The main aim of these PTs is to verify the performance of those laboratories and to ensure comparability of the results that they report.
One of the latest PTs was testing abilities of the laboratories to accurately detect and precisely measure massic activities (in Bq/kg) of 131I, 134Cs and 137Cs in maize powder. Maize dominates animal feed in Europe and it is very important to monitor these primary fall-out products in maize following a nuclear accident or incident.
Overall, the results of the participating laboratories are very good – over 90% of the 120 participating laboratories were able to provide correct activity values for each of the radionuclides. This indicates that the monitoring competencies of European laboratories measuring these three radionuclides in feed using gamma-ray spectrometry are well maintained. Two minor persisting problems are the general underestimation of uncertainties and the correct application of coincidence summing correction.
It must also be noted that the field of environmental radioactivity monitoring is a vast field that encompass many radionuclides (about 200) and many different matrices that will require a multitude of measurement techniques (about 10) to cover. For an overview, see a recent report: Radioactivity monitoring: How the JRC verifies results from monitoring within the European Union on EU Science Hub. Very few labs master all radionuclides and matrices.
More information can be found on the JRC Technical report Evaluation of the 2017 EC Proficiency Test on 131I, 134Cs and 137Cs in maize powder on EU Science Hub and Evaluation of a proficiency test of 131I, 134Cs and 137Cs in maize powder on ScienceDirect.
- 24 August 2020