Isotope dilution sector-field inductively coupled plasma mass spectrometry combined with extraction chromatography for rapid determination of 241Am in marine sediment samples: A case study in Sagami Bay, Japan
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241Am is a useful tracer for understanding biogeochemical processes in the marine environment. 241Am also poses a potential radiation threat to human health due to the continuous increase of its concentration in the global environment. We report a rapid analytical method for determining 241Am in marine sediments using isotope dilution sector-field inductively coupled plasma mass spectrometry (SF-ICP-MS) combined with a high-efficiency sample introduction system (APEX-Q). A selective CaF2 co-precipitation procedure followed by TRU extraction chromatography was employed to effectively remove the major sediment matrix and to pre-concentrate 241Am. We achieved an extremely low detection limit of 0.32 fg/g or 0.041 mBq/g (for 1 gram sediment), which is better than that of alpha spectrometry, and it allowed the accurate determination of 241Am in low-level marine sediment samples. The accuracy and precision of the developed analytical method was evaluated using a laboratory prepared Am isotope standard solution and Ocean Sediment reference material (IAEA-368). The results were satisfactory. For sediment samples, overall chemical recoveries varied from 60–90%. The developed method was applied to the study of 241Am depth distribution in Sagami Bay, Japan, where we observed different depth profiles between 241Am activity and 239+240Pu activity.
KeywordsIsotope dilution SF-ICP-MS extraction chromatography 241Am marine sediments Sagami Bay
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- Epov, V. N., K. Benkhedda, D. Brownell, R. J. Cornett and R. D. Evans (2005): Comparative study of three sample preparation approaches for the fast determination of americium in urine by flow injection ICP-MS. Can. J. Anal. Sci. Spectroscopy, 50, 14–22.Google Scholar
- Horwitz, E. P., M. L. Dietz, R. Chiarizia, H. Diamond, S. L. Maxwell, III and M. R. Nelson (1995): Separation and preconcentration of actinides by extraction chromatography using a supported liquid anion exchanger: application to the characterization of high-level nuclear waste solutions. Anal. Chim. Acta, 310, 63–78.CrossRefGoogle Scholar
- Nakanishi, T., Y. Shiba, M. Muramatsu and M. A. Haque (1995): Estimation of mineral aerosol fluxes to the Pacific by using environmental plutonium as a tracer. p. 15–30. In Biogeochemical Processes and Ocean Flux in the Western Pacific, ed. by H. Sakai and Y. Nozaki, TERRAPUB, Tokyo.Google Scholar
- Povinec, P. P., H. D. Livingston, S. Shima, M. Aoyama, J. Gastaud, I. Goroncy, K. Hirose, L. Huynh-Ngoc, Y. Ikeuchi, T. Ito, J. La Rosa, L. Liong Wee Kwong, S. H. Lee, H. Moriya, S. Mulsow, B. Oregioni, H. Pettersson and O. Togawa (2003): IAEA’97 expedition to the NW Pacific Ocean-results of oceanographic and radionuclide investigations of the water column. Deep-Sea Res. II, 50, 2607–2637.CrossRefGoogle Scholar
- Truscott, J. B., P. Jones, B. E. Fairman and E. H. Evans (2001a): Determination of actinides in environmental and biological samples using high-performance chelation ion chromatography coupled to sector-field inductively coupled plasma sector field spectrometry. J. Chromatogr. A, 928, 91–98.CrossRefGoogle Scholar
- Truscott, J. B., P. Jones, B. E. Fairman and E. H. Evans (2001b): Determination of actinide elements at femtogram per gram levels in environmental samples by on-line solid phase extraction and sector-field inductively coupled plasma sector field spectrometry. Anal. Chim. Acta, 433, 245–253.CrossRefGoogle Scholar
- UNSCEAR (1993): Reports on ionizing radiation to General Assembly. United Nations Scientific Committee on the Effects of Atomic Radiations, New York.Google Scholar
- Worldwide marine radioactivity studies (WOMARS) (2004): Radionuclide levels in oceans and seas. IAEA, Vienna, IAEA-TECDOC-1429.Google Scholar
- Yamamoto, M., K. Komura and M. Sakanoue (1981): A simple sequential separation method of Pu and Am by anion exchange and extraction chromatography. Radiochim. Acta, 29, 205–208.Google Scholar