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

Sn-126 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 Sn-126 in construction materials by combining the HCl-free solid phase extraction on TEVA (R) 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 Te-126 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 Sn-126 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 Sn-126 in construction materials.

Automated summary

A reliable method combining chemical separation and mass spectrometry was proposed to verify the presence of Sn-126 in construction materials. The method showed high chemical recovery and sensitivity, meeting the detection requirements for this nuclide.