Development of the NIST bone ash standard reference material for environmental radioactivity measurement

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• 作者：Lin ; Zhichao ; Inn ; K. G. W. ; Altzitzoglou ; T. ; Arnold ; D. ; Cavadore ; D. ; Ham ; G. J. ; Korun ; M. ; et. al.
• 刊名：Applied Radiation and Isotopes
• 出版年：1998
• 出版时间：September 11, 1998
• 年：1998
• 卷：49
• 期：9-11
• 页码：1301-1306
• 全文大小：247 K

文摘

The bone ash standard reference material (SRM), a blend of 4 % contaminated human bone and 96 % diluent bovine bone, has been developed for radiochemical method validation and quality control for radio-bone analysis. The massic activities of ⁹⁰Sr, ²²⁶Ra, ²³⁰Th, ²³²Th, ²³⁴U, ²³⁵U, ²³⁸U, ²³⁸Pu, ^(239+240)Pu and ^(243+244)Cm were certified using a variety of radiochemical procedures and detection methods. Measurements confirmed undetectable radionuclide heterogeneity down to a sample size of 5 g, thereby implying adequate blending of particulate materials with dilution factors of up to 17,900. The results among most of the intercomparison laboratories and their methods were consistent. Disequilibrium was observed for decay chains: ²³⁴U(0.67 mBq/g)–²³⁰Th(0.47 mBq/g)–²²⁶Ra(15.1 mBq/g)–²¹⁰Pb(23 mBq/g)–²¹⁰Po(13 mBq/g) and ²³²Th(0.99 mBq/g)–²²⁸Ra(6.1 mBq/g)–²²⁸Th(7.1 mBq/g). The disequilibria were the results of mixing occupationally contaminated human bone with natural bovine bone and the fractionation during internal biological processes. The massic activity of ²¹⁰Pb, ²²⁸Th and ²⁴¹Am were not certified because of insufficient ²²⁸Ra and ²⁴¹Pu data and lack of knowledge in how ²²²Rn and its daughters will be fractionated in the SRM bottle over time.