ASTM_D_8026_-_16.pdf

Designation:D802616Standard Practice forDetermination of Tc-99 in Water by Inductively CoupledPlasma Mass Spectrometry(ICP-MS)1This standard is issued under the fixed designation D8026;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 Technetium is separated and concentrated from a watersample by extraction chromatography using its chemicalanalog,rhenium,as a tracer.The ratio of technetium to rheniumis measured by inductively coupled plasma mass spectrometry(ICP-MS)to then quantify the99Tc concentration.1.1.1 This practice is provided as an alternative to TestMethod D7168 which provides for a different separation mediageometry and measurement by liquid scintillation spectrom-etry.Similar detection limits should be attainable by thismethod.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C1387 Guide for the Determination of Technetium-99 inSoilD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water AnalysisD7168 Test Method for99Tc in Water by Solid Phase Extrac-tion DiskD7902 Terminology for Radiochemical Analyses3.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard,refer toTerminologies D1129 and D7902.4.Summary of Practice4.1 A known quantity of Re is added to a known volume ofa filtered water sample.The sample is heated in the presence ofperoxide to ensure the Tc and Re are in the oxidized form.TheTc and Re are then extracted from the sample using anextraction chromatography resin loaded in a column.3,4Theresin is rinsed of some co-retained elements and then the Tcand Re are co-eluted from the resin.4.2 An ICP-MS is used to determine the ratio of Tc relativeto the Re tracer;the Re is used as an internal standard tomonitor instrument response as well as to correct for chemicalyield of the Tc through the column separation.5.Significance and Use5.1 Technetium-99 is produced by the fission of uraniumand plutonium,and has been released to the environment vianuclear weapons testing and nuclear materials processing.Inan oxidizing environment,it exists as the very mobile pertech-netate ion,TcO4,which is an analog to nitrate and can betaken up by living organisms.Monitoring of99Tc in watersaround nuclear processing facilities is part of a completeenvironmental monitoring program.5.2 Technetium-99 is a long-lived(half-life 2.1E+5years),weak beta(maximum beta energy of 293 keV)emittingradioisotope.There are no stable isotopes of Tc.Thus thedetermination of its activity concentration presents uniquechallenges to traditional radiochemical determination methods.This method provides an alternative to the spiked/unspikedreplicate method of Method D7168 and uses options presentedin Guide C1387 for the determination of99Tc in soil.1This practice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.04 on Methods of RadiochemicalAnalysis.Current edition approved Feb.15,2016.Published March 2016.DOI:10.1520/D8026-16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Tagami,K.,and Uchida,S.,Analytica Chimica Acta,Vol 405,2000,pp.227229.4Kabai,E.,Beyermann,M.,Seeger,J.,Savkin,B.T.,Stanglmaier,S.,andHiersche,L.,Applied Radiation and Isotopes,Vol 81,2013,pp.641.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Interferences6.1 Any element with a mass-to-charge ratio(m/z)of 99(that is,naturally occurring isotope of99Ru,or other artificiallyproduced elements of sufficient half-life with similar m/z)caninterfere when using mass spectrometry for quantification ofthe99Tc activity.Any element with the same m/z as the isotopeused as an isotope dilution tracer or internal standard,that is,m/z of 185 or 187,will cause a bias in the yield correction.Corrections should be included in the mass spectrometry datareduction for known interferences.6.2 High levels of nitrate in the sample could lead tosaturating the active sites on the resin and cause low recoveryof the T