A rapid method for accurate determination of 241Am by sector field inductively coupled plasma mass spectrometry and its application to Sellafield site soil samples

Abstract

Americium is one of the toxic radionuclides that are released during nuclear weapon tests and nuclear industry activities. To quickly characterize the released Am for nuclear emergency response, a new method was developed by combining HNO₃ leaching, co-precipitation, extraction chromatography and SF-ICP-MS measurement; specifically, CaF₂ co-precipitation is used to remove major metals, extraction chromatography by UTEVA, DGA-N and TEVA resins is used to remove interfering elements (IEs) and rare earth elements (REEs), and an Apex-ICP-MS analytical system is used to determine Am isotopes. The method was evaluated with three standard reference materials (IAEA-soil-6, IAEA-384 and IAEA-385) and the results showed that ²⁴¹Am activities were accurately determined, in a short analysis time (2 days), with a high decontamination factor for the IEs (e.g. DF (Pu) = 7.4 × 10⁵), and a high chemical recovery (63–88%). This method was further applied to analyze soil samples collected around the Sellafield nuclear complex, and high ²⁴¹Am activities (5.24–1179 mBq g⁻¹) were observed.