Abstract
Strontium-90 is a major radioactive nuclide released by nuclear accidents and discharge waste. Input of such radioactive nuclide into earth surface environment causes potential threat of long-term internal exposure when taken up by organism. Rapid and precise measurement of 90Sr in variety of environmental sample is important to understand the distribution and dynamics of 90Sr in the local environment after the accident and to assess the effect of radioactive nuclide inputs on bodies. However, previous 90Sr measurement techniques have drawbacks such as long measurement times for radiometry and high detection limits for mass spectrometry. Here we present a technique to accurately measure a significantly small amount of 90Sr in natural environmental samples using an energy-filtered thermal ionization mass spectrometry. Our technique achieved a 90Sr detection limit of 0.23 ag, which corresponds to a 90Sr activity of 1.2 µBq. The detection limit was lowered by two orders of magnitude compared with the previous mass spectrometric 90Sr analyses. The ability of our technique will expand the applicability of mass spectrometric 90Sr survey not only to the rapid 90Sr survey upon nuclear accidents but also to study a long-term environmental diffusion of radioactive materials using size-limited environmental and biological samples.
Highlights
Strontium-90 is a major radioactive nuclide released by nuclear accidents and discharge waste
A precise measurement the isotope ratio of 90Sr and stable Sr is important to determine the understanding of right dynamics of 90Sr in the local environment surrounding the accident s ite[19]
We focused on bringing out the performance of modern Thermal ionization mass spectrometry (TIMS) instruments to perform an accurate 90Sr/88Sr measurement of environmental and biological samples with low 90Sr activity using an effective energy filtering technique for 90Sr detection
Summary
Strontium-90 is a major radioactive nuclide released by nuclear accidents and discharge waste. The reaction of the ions with O2 gas is used in a dynamic reaction cell (DRC) technique to reduce the 90Zr ion transmission[2,24,25] This technique achieves abundance sensitivities, defined as the intensity ratio between 88Sr peak tail on m/z = 89.908 and 88Sr, on the order of 1 0−9 2,19. The highly efficient ICP ion source mainly produces abundant polyatomic or polyvalent ions from the sample solution’s solvents, Ar gas, and trace impurities in the sample solution, and such ions exist across the entire m/z range It emits Ar gas-related ions such as A r+ and A rO+ at significantly high intensities, which may cause non-spectrum interference of the peak tails. Even with the ICP-MS/MS technique, the background signal was reported as 0.1–0.2 cps when aspirating a blank solution[28], showing that noise signals of sub-cps level are inevitable while using the ICP ion source
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
