A Study of the Rn-222 and Ra-226 Analysis in Aqueous Samples with a Low-Level Liquid Scintillation Counter and Pulse-Shape Analysis

저준위 액체섬광계수기와 파형분석법을 이용한 수용액 중 라돈-222 및 라듐-226의 분석법 연구

  • Received : 1999.03.09
  • Published : 1999.10.25

Abstract

A method for measuring Rn-222 and Ra-226 in aqueous sample using liquid scintillation counting technique has been studied. The Rn-222 was extracted easily from the water sample (10 mL) by 12 mL of xylene based organic scintillant. After radioactive equilibrium between Rn-222 and its alpha emitting decay products for three hours, the alpha activity from Rn-222 and its decay products were measured in a scintillation vial using the Wallae $1220^{TM}$ Quantulus liquid scintillation counter. Ra-226 concentration in aqueous sample was determined, after isolation of Ra-226 from the sample matrix, by extraction the ingrowth of the Rn-222 and its alpha emitting decay products with xylene based organic scintillant. The optimum pulse-shape analysis (PSA) value was evaluated by the figure of merit (FM) criterion. Minimum detectable activity (MDA) is about 0.14 Bq/L (3.78 pCi) for the region of Rn-222 and its alpha emitting decay products and 0.06 Bq/L (1.63 pCi) for the region of Po-214 respectively, with 200 min, counting time at PSA level 100 in the low-diffusion polyethylene vial and xylene based cocktail solution. Experiment on the optimum sample-cocktail volume ratio, the influence of agitation and the diffusion of radon from vial were carried out.

Keywords

Radon-222 and Radium-226;liquid scintillation counter

Acknowledgement

Supported by : 과학기술부

References

  1. Environ. Inter. v.14 E. L. Cooper;R. M. Brown;G. M. Milton
  2. Ratioack. Radiochem. v.4 G. T. Cook;R. Anderson
  3. Appl. Radiat. Isot. v.40 Y. Murase;Y. Homma;M. Takiue
  4. Appl. Radiat. Isot. v.48 G. Manjon;I. Viogue;H. Moreno;R. Garcia-Tenorio;M. Garcia-Leon
  5. Anal. Chem. v.40 L. Currie
  6. Private Communication Risk of Naturally Occuring Radionuclides in Drinking Water S. Y. Lee
  7. J. Korean Asso. Radiat. Prot. v.20 H. J. Woo;Y. Y. Toon;S. Y. Cho;S. K. Chun
  8. 한일. 환경세미나(대기환경과 Radon을 중심으로)발표논문집 김운수;추병길;정주영;김윤신;이철민
  9. Report to the general assembly Sources, Effects of Ionization Radiation United Nations Scientific Committe on the effect of atomic radiation
  10. Environmental Chemistry(2nd) Peter O;nell
  11. Health Phys. v.69 C. Mancini;G. giannelli
  12. J. Radioanal. Nucl. Chem., Letters v.186 no.2 H. Bem;Y. Y. Y. Bakir;F. Bou-Rabee
  13. Health Phys. v.60 E. Vitz
  14. Health Phys. v.33 H. M. Prichard;T. F. Gessell
  15. ARL/TR040 An analytical method for $radium(_{226}Ra$ in enveronmental samples by the use of liquid scintillation counting M. B. Cooper;M. J. Wilks
  16. Radiat. Prot. Dosimetry v.45 F. Schonhofer
  17. J. Environ. radioactivity v.38 Z. A. Tayyed;A. R. Kinsara;S. M. fraid
  18. J. Radioanal. Nucl. Chem. v.161 J. M. Barnett;J. W. Mckleveen
  19. Application of LSC D. L Horrks
  20. Econ. Environ. Geol. v.29 J. H. Han;K. H. Park
  21. INEL-95/0546 Determination of radium in water F. A. Hohorst;M. W. Huntley;S. D. Hantenstein
  22. J. Korean Asso. Radiat. Prot. v.20 C. K. Kim;C. S. Kim
  23. RADIOCARBON Scintillation Spectrometry J. M. Pates;G. T. Cook;a. B. Mackenzie;E. Noakes(ed.);f. schonhoffer(ed.);H. A. Polach(ed.)
  24. Environ. Health Perspect. v.70 N Harley;J. M. Samet;F. T. Hess;J. Muller;D. Thomas
  25. Sci. Total Environ. v.130-131 L. Salonen
  26. Appl. Radiat. Isot. v.47 P. Theodorsson
  27. EPA/570.9-91/700 National Primary Drinking Water Regualtions for Radionuclides U. S. Environmental Protection Agency
  28. Analyst v.14 F. Schonhofer
  29. J. Environ. Radioact. v.37 K. Freyer;H. C. Treutler;J. Dehnert;W. Nestler