Determination of environmental gaseous 129I trapped in charcoal cartridges by ICP-MS/MS

International audience; For environmental monitoring and radioecological studies, organic and inorganic 129I is often trapped in active charcoal. The analysis of this radionuclide can be difficult because of the low-level activities involved and its physico-chemical properties (e.g., volatility and multiple oxidation degrees). This study proposes a new method for 129I analysis by ICP-MS/MS, which consists in the extraction of iodine from charcoal by acid digestion followed by purification using a commercial specific resin. This new method allows reaching environmental levels of gaseous 129I near the fuel reprocessing plant of La Hague (France) with a limit of detection of only 2 mBq sample-1.