1、Designation: C 1473 05Standard Test Method forRadiochemical Determination of Uranium Isotopes in Urineby Alpha Spectrometry1This standard is issued under the fixed designation C 1473; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、 the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method is applicable to the determination ofuranium in urine at levels of detection dependent
3、on samplesize, count time, detector efficiency, background, and traceryield. It is designed as a screening tool for detection of possibleexposure of occupational workers.1.2 This test method is designed for 50 mL of urine. Thistest method does not address the sampling protocol or samplepreservation
4、methods associated with its use.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 limitati
5、ons prior to use.2. Referenced Documents2.1 ASTM Standards:2C 1000 Test Method for Radiochemical Determination ofUranium Isotopes in Soil by Alpha SpectrometryC 1163 Test Method for Mounting Actinides for AlphaSpectrometry Using Neodymium FluorideC 1284 Practice for Electrodeposition of the Actinide
6、s forAlpha SpectrometryD 1193 Specification for Reagent WaterD 3084 Practice for Alpha-Particle Spectrometry of WaterD 3648 Practices for Measurement of Radioactivity3. Summary of Test Method3.1 A urine sample with232U tracer solution added iswet-ashed with nitric acid and hydrogen peroxide to destr
7、oyorganic material. The uranium-bearing solution is converted toa hydrochloric acid medium. Uranium is absorbed on an anionexchange column from a 9 M hydrochloric acid solution andeluted with 0.1 M hydrochloric acid solution. The separateduranium is prepared for alpha spectrometric measurementeither
8、 by electrodeposition onto a metal disk or coprecipitationwith neodymium fluoride and filtration onto a membrane filter.4. Significance and Use4.1 This test method is used to detect possible exposures touranium isotopes from occupational operations.5. Interferences5.1 The presence of232U in the urin
9、e sample will be maskedby the tracer addition. The alpha energies of233U and234Ucannot be fully resolved by alpha spectrometric measurement.A table of uranium isotope alpha energies is given in AppendixX1. If neptunium is present in the sample in the plus fouroxidation state, it will coelute with th
10、e uranium.6. Apparatus6.1 Alpha Spectrometry SystemRefer to Test MethodsC 1000, C 1163, D 3084, and D 3648 for guidance.6.2 Electrodeposition ApparatusRefer to Practice C 1284for guidance.6.3 Neodymium Fluoride PrecipitationRefer to TestMethod C 1163 for guidance.6.4 Borosilicate Beakers or Flasks,
11、250 mL.6.5 Borosilicate Beakers, 150 and 250 mL.6.6 Borosilicate Graduated Glass Cylinders, 5, 25, 100, and1000 mL.6.7 Ion Exchange Columns, disposable polypropylene, withpolyethylene frit, $5-mL capacity.36.8 Ion Exchange Column Reservoir, funnel, polypropy-lene, 100-mL capacity.NOTE 1See Fig. 1 fo
12、r a typical ion exchange column-reservoir setup.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatthe reagents conform to the specifications of the Committee on1This test method is under the jurisdiction of ASTM Committ
13、ee C26 on NuclearFuel Cycle and is the direct responsibility of Subcommittee C26.05 on TestMethods.Current edition approved June 1, 2005. Published June 2005. Originallyapproved in 2000. Last previous edition approved in 2000 as C 1473 00.2For referenced ASTM standards, visit the ASTM website, www.a
14、stm.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.3Various column configurations are available from Bio-Rad Laboratories, LifeScience Group, Hercules, CA; Whatman LabSales,
15、 Hillsboro, OR; and Perkin ElmerL:ife Sciences, Akron, OH.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Analytical Reagents of the American Chemical Society, wheresuch specifications are available.4Other grades may be used,provided
16、 it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.7.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water as definedby Type III of Specification D 1193.7.3 R
17、eagent purity shall be such that the measured radioac-tivity of blank samples is minimized.7.4 Anion Exchange ResinAnalytical grade, Type 1, 8 %cross linked, 100-200 mesh, chloride form.57.5 Hydrochloric Acid (9 M)Mix 750 mL of concentratedHCl with water and dilute to 1 L.7.6 Hydrochloric Acid (sp g
18、r 1.19)Concentrated hydro-chloric acid (HCl).7.7 Hydrochloric Acid (0.1 M)Mix 8.3 mL of concen-trated HCl with water and dilute to 1 L.7.8 Hydrogen Peroxide (30 %).7.9 Nitric Acid (8 M)Mix 500 mL of concentrated nitricacid with water and dilute to 1 L.7.10 Nitric Acid (sp gr 1.4)Concentrated nitric
19、acid(HNO3).7.11 Uranium-232, standard solution.68. Hazards8.1 WarningAdequate laboratory facilities, such as fumehoods and controlled ventilation, along with safe techniquesmust be used in this procedure. Site-specific policies for thehandling of biological materials must be adhered to. Extremecare
20、should be exercised in using hydrofluoric and other hot,concentrated acids. The use of proper gloves is recommended.9. Sampling9.1 Collect the urine sample in accordance with the site-specific protocol.9.2 Preserve the urine sample in accordance with the site-specific protocol.10. Calibration and St
21、andardization10.1 If a traceable standard232U solution is not available foruse as a tracer, standardize a freshly prepared sample of232U;for guidance refer to Practice D 3648.A232U standard mayalso be used to determine the detection efficiency of thea-spectrometry system which, in turn, can be used
22、to calculatethe chemical yield of each sample and the lower limit ofdetection (LLD) of this test method.11. Procedure11.1 Sample Preparation:11.1.1 Measure 50 mL of urine in a 100-mL graduatedcylinder.11.1.2 Transfer the urine to a 250-mL beaker or flask.11.1.3 Rinse the cylinder twice with 5 mL of
23、8 M HNO3andadd the rinsings to the beaker or flask.11.1.4 Add an appropriate amount of232U tracer solution tothe sample (ca. 0.02 Bq or as prescribed in the site-specificprotocol) and swirl the vessel to mix.11.1.5 Evaporate the contents of the vessel to near drynesson a medium hot plate.11.1.6 Remo
24、ve the vessel from the hot plate and cool for 1min.11.1.7 Add 10 mL of concentrated HNO3to the vessel.Swirl to mix.11.1.8 Return the vessel to the hot plate and evaporate thesolution to near dryness.11.1.9 Remove the vessel from the hot plate and allow tocool for 1 min.11.1.10 Slowly add 10 to 15 mL
25、 of 30 % hydrogen peroxideto the vessel to cover the residue. Swirl the vessel to mix.11.1.11 Return the vessel to the hot plate and evaporate thesolution to near dryness.11.1.12 Repeat 11.1.9 and 11.1.10.11.1.13 Return the vessel to the hot plate and evaporate thesolution to obtain a white sample r
26、esidue.11.1.14 Remove the vessel from the hot plate and allow tocool for 1 min.11.1.15 Add 10 to 15 mL of concentrated HCl to the vesseland swirl to mix.11.1.16 Return the vessel to the hot plate and evaporate thesolution to near dryness.11.1.17 Remove the vessel from the hot plate and allow tocool
27、for 1 min.11.1.18 Repeat 11.1.15-11.1.17 twice more. Proceed to11.1.19.11.1.19 Add 75 mL of 9 M HCl to the vessel and heat gentlyto dissolve the residue.11.1.20 Remove the vessel from the hot plate and cool toroom temperature.11.2 Anion Exchange Separation:11.2.1 Measure 3 mL of settled, water slurr
28、ied anion ex-change resin.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and th
29、e United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.5Resin available from Bio-Rad Laboratories, (Hercules, CA) and EichromTechnologies, Inc. (Darien, IL).6Uranium-232 traceable to a national standards organization.FIG. 1 Typical Ion Exchange C
30、olumn ArrangementC147305211.2.2 Place a 250-mL beaker under an empty column.Transfer the resin to the column with water. Allow the water todrain from the column.11.2.3 Insert a glass wool plug on the top of the resin bed.11.2.4 Pour 30 mL of 9 M HCl into the ion exchangecolumn reservoir and allow th
31、e acid to drain through tocondition the resin column.11.2.5 Transfer the sample solution to the ion exchangecolumn reservoir. Pass the sample solution through the resincolumn.11.2.6 Rinse the sample vessel with 10 mL of 9 M HCl andadd the rinse to the column reservoir. Repeat the rinse once andallow
32、 the solution to drain to the top of the glass wool plug.11.2.7 Wash the resin column with 30 mL of 9 M HCl andallow the acid to drain from the column.11.2.8 Remove the beaker containing the combined wasteand wash solutions from beneath the resin column. Discard thecombined solutions in accordance w
33、ith the site-specific dis-posal requirements for acids.11.2.9 Place a clean 150-mL beaker under the resin column.11.2.10 Elute the uranium from the resin column by pouring50 mL of 0.1 M HCl into the column reservoir and allowing itto drain through.11.2.11 Place the beaker containing the eluted urani
34、um on ahot plate and evaporate the solution to just dryness. Removethe beaker from the hot plate and cool for 1 min.11.2.12 Add 2 to 3 mL of concentrated HNO3to the beaker.11.2.13 Repeat 11.2.11 and 11.2.12 until the residue iswhite.11.2.14 Remove the beaker from the hot plate and cool for1 min.11.2
35、.15 Add 5 mL of concentrated HCl to the beaker andevaporate to dryness. Remove the beaker from the hot plateand cool for 1 min.11.2.16 Repeat 11.2.15 twice more.11.3 Electrodeposition or Neodymium Fluoride Precipita-tion:11.3.1 For electrodeposition, refer to Practice C 1284.11.3.2 For neodymium flu
36、oride precipitation, refer to TestMethod C 1163.11.4 Alpha Spectrometry Measurement:11.4.1 Measure the sample overnight (1000 min) or longerin an alpha spectrometry system.11.4.2 Measure the background and reagent blank activityfor the regions of interest. Correct each uranium isotopeactivity for ba
37、ckground and reagent blank activity.12. Calculation12.1 Refer to Test Method C 1000 for calculation of activity.12.2 Calculate the lower limit of detection (LLD)7inbecquerels at the 95 % confidence limit, as follows, assumingequal counting times for the background and sample:LLD95 %52.71 1 4.66 SBY!
38、 Tb! E!(1)where:SB= standard deviation of the detector background for theregion of interest, counts,Tb= background counting time, s,Y = radiometric yield of the uranium-232 tracer, andE = counting efficiency for the alpha spectrometry detec-tor.12.2.1 Typical values for these parameters are as follo
39、ws:SB= 1 count per 60 000 s,Tb=Ts= 60 000 s,Y = 75 % (0.75 in the preceding LLD calculation), andE = 30 % (0.30 in the preceding LLD calculation).13. Precision and Bias13.1 PrecisionReplicate reference samples, blind qualitycontrol (QC) samples, and reagent blanks were analyzed at theWestinghouse Sa
40、vannah River Company Radiobioassay Labo-ratory. These analyses were performed over a 12-month periodby several analysts as blind samples in the routine samplestream. The results of these studies are summarized in Table 1.13.2 BiasThe bias is defined as follows:Bias, % = 100* (observed value-known va
41、lue)/known valueaveraged over the entire data setThe uncertainty in the NIST standard of 2 % is included in thisestimate.14. Keywords14.1 alpha spectrometry; ion exchange separation; uranium;urine7Available from “Upgrading Environmental Radiation Data,” U.S. Environmen-tal Protection Agency, EPA 520
42、/1-80-012, August 1980.TABLE 1 Summary of Precision and Bias DataSample TypeBlind Quality Control ReferenceNumber of analyses 103 140Concentration234U(BqL1) 0.17 0.025Precision, % 30 11Bias, % 4 1.5Concentration238U(BqL1) 0.042 0.058Precision, % 20 15Bias, % 7 6Reagent BlanksNumber of analyses 80mea
43、n 6 SD234U 0.0007 6 0.0013238U 0.0008 6 0.0013C1473053APPENDIX(Nonmandatory Information)X1.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination
44、 of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdraw
45、n. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your co
46、mments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single o
47、r multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).TABLE X1.1 Properties of Uranium Isotopes of Interest inEnvironmental SamplesAIsotope Half
48、-Life, years Alpha Energies, MeV (abundance)232U 68.9 5.320 (68.6 %), 5.263 (31.2 %)233U 1.592 3 1054.825 (84.4 %), 4.783 (13.2 %)234U 2.454 3 1054.776 (72.5 %), 4.723 (27.5 %)235U 7.037 3 1084.395 (85 %), 4.370 (6 %), 4.597, (5 %)236U 2.342 3 1074.494 (74 %), 4.445 (26 %)238U 4.468 3 1094.196 (77 %), 4.147 (23 %)AAvailablefromBrowne,E.,andFirestone,R.B., Table of Radioactive Isotopes,(V. S. Shirley, Ed.), John Wiley and Sons, Inc., 1986.C1473054
