Development of HCl-free solid-phase extraction combined with ICP-MS/MS for rapid assessment of difficult-to-measure radionuclides. Part II: Highly sensitive monitoring of 126Sn in concrete rubble

126 Sn is one of the long-lived fission products that might have been released into the environment after the Fukushima nuclear accident in Japan in 2011. The presence of radionuclides must be monitored for the proper treatment of wastes obtained from decommissioning accident-related nuclear facilities and the surrounding environment. In the work, we propose a reliable method for verifying the presence of 126 Sn in construction materials by combining the HCl-free solid phase extraction on TEVA® resin and a selective measurement by inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). The method has been optimized and characterized. More than 95% of chemical recovery was achieved for Sn from typical concrete matrixes. The interference caused by an isobar 126 Te and possible polyatomic interferences from matrixes were effectively suppressed by the developed chemical separation and the tandem MS/MS configuration. The total decontamination factor for the Te interference was of the order of 10 5 . The estimated method detection limit for 126 Sn in concrete as measured at m/z = 160 was 12.1 pg g − 1 , which is equivalent to 6.1 mBq g − 1 . In conclusion, the sensitivity of the developed method is comparative to the conventional radiation-counting methods and sufficient for verifying the presence of 126 Sn in construction materials.