Deposition Velocity of Iodine Vapor ($(I_2)$) for Radish Plants and Its Root-Translocation Factor : Results of Experimental Exposures

요오드 증기($I_2$)의 무 작물체에 대한 침적속도 및 뿌리 전류계수 : 피폭실험 결과

  • Received : 2009.06.26
  • Accepted : 2010.03.08
  • Published : 2010.06.30

Abstract

In order to measure the deposition velocity of $I_2$ vapor for radish plants and its translocation factor for their roots, radish plants were exposed to $I_2$ vapor for 80 min. at different growth stages between 29 and 53 d after sowing. The exposure was performed in a transparent chamber during the morning time. Deposition velocities ($ms^{-1}$) were on the whole in the range of $1.0{\times}10^{-4}{\sim}2.0{\times}10^{-4}$ showing an increasing tendency with an increase in the biomass density. The results showed some agreement with existing reports that a higher relative humidity would lead to a higher deposition velocity. The acquired deposition velocities were lower than by factors of several tens than some field measurements probably due to a very low wind speed (about $0.2\;ms^{-1}$) in the chamber. Translocation factors (ratio of the total iodine in the roots at harvest to the total plant deposition), estimated in a more or less conservative way, were $1.3{\times}10^{-3}$ for an exposure at 29 d after sowing and $5.0{\times}10^{-3}$ for an exposure at 53 d after sowing. In using the present experimental data, meteorological conditions and chemical and physical forms of iodine need to be carefully considered.

무에 대한 $I_2$ 증기의 작물체 침적속도와 뿌리 전류계수를 측정하기 위하여 파종 후 29 일에서 53 일 사이에 생육시기별로 작물체를 $I_2$ 증기에 80 분 간 피폭시켰다. 피폭은 오전 중에 투명한 상자 내에서 수행되었다. 침적속도($ms^{-1}$)는 대체로 $1.0{\times}10^{-4}{\sim}2.0{\times}10^{-4}$의 범위로 생육밀도가 높을수록 증가하는 경향이었다. 또한 상대습도가 높을 경우 값이 커진다는 기존 보고와 어느 정도 일치하였다. 본 침적속도는 몇몇 야외 측정치보다 수 십 배 정도 낮았고 이는 주로 피폭상자 내의 낮은 풍속($0.2\;ms^{-1}$ 내외)에 기인하는 것으로 추정되었다. 뿌리 전류계수(작물체 총침적량에 대한 수확시 뿌리 내 함유량의 비)는 다소 보수적으로 계산하여 파종 후 29 일 피폭에서 $1.3{\times}10^{-3}$, 파종 후 53 일 피폭에서는 $5,0{\times}10^{-3}$이었다. 본 실험결과의 이용에 있어서는 기상 조건, 요오드의 물리화학적 형태 등에 유의할 필요가 있다.

Keywords

References

  1. 강상훈, 한선호, 이흥래, 지광용, 이인구, "RI 폐기물 내방사성 요오드 분석을 위한 분리 및 회수," 방사성폐기물학회지, 5, pp. 267-272 (2007).
  2. H. Noguchi and M. Murata, "Physicochemical speciation of airborne 131I in Japan from Chernobyl," J. Environ. Radioactivity, 7, pp. 65-74 (1988). https://doi.org/10.1016/0265-931X(88)90042-2
  3. A. Aguero, P. Pinedo, I. Simon, D. Cancio, M. Moraleda, C. Trueba and D. Perez-Sanchez, "Application of the Spanish methodological approach for biosphere assessment to a generic high-level waste disposal site," Science of the Total Environment, 403, pp. 34-58 (2008). https://doi.org/10.1016/j.scitotenv.2008.04.054
  4. D. J. Ashworth and G. Shaw, "A comparison of the soil migration and plant uptake of radioactive chlorine and iodine from contaminated groundwater," J. Environ. Radioactivity, 89, pp. 61-80 (2006). https://doi.org/10.1016/j.jenvrad.2006.03.006
  5. 성석현, 정의영, 김기홍, "국내 방사성폐기물 특성과 방사성폐기물 처분시설 폐기물 인수기준," 방사성폐기물학회지, 6, pp. 347-356 (2008)
  6. M. Eisenbud and M. E. Wrenn, "Biological disposition of radioiodine-a review," Health Physics, 9, pp. 1133-1139 (1963). https://doi.org/10.1097/00004032-196312000-00009
  7. P. J. Barry and A. C. Chamberlain, "Deposition of iodine onto plant leaves from air," Health Physics, 9, pp. 1149-1157 (1963). https://doi.org/10.1097/00004032-196312000-00011
  8. Y. Nakamura and Y. Ohmomo, "Factors used for the estimation of gaseous radioactive iodine intake through vegetation-II. uptake of elemental iodine by spinach leaves," Health Physics, 38, pp. 315-320 (1980). https://doi.org/10.1097/00004032-198003000-00005
  9. F. P. Hungate, J. F. Cline, R. L. Uhler and A. A. Selders, "Foliar sorption of $^{131}I$ by plants," Health Physics, 9, pp. 1159-1166 (1963). https://doi.org/10.1097/00004032-196312000-00012
  10. R. K. Singhal, U. Narayanan and I. S. Bhat, "Laboratory evaluation of interception and translocation of $^{131}I$ in fenugreek and okra plants," Health Physics, 67, pp. 529-534 (1994). https://doi.org/10.1097/00004032-199411000-00008
  11. 최용호, 임광묵, 이창민, 박효국, 박두원, 최근식, 최희주, 이한수, 이창우, "벼에 대한 원소상 요오드 증기(I2)의 직접오염경로 해석 실험," 대한방사선방어학회지, 29, pp. 165-172 (2004).
  12. J. E. Till and H. R. Meyer, Radiological Assessment, U.S. Nuclear Regulatory Commission, NUREG/CR-3332, ORNL-5968 (1983).
  13. International Atomic Energy Agency, Handbook of Parameter Values for the Prediction of Radionuclide Transfer in Temperate Environments, Technical Reports Series No. 364, IAEA, Vienna (1994).
  14. Y. H. Choi, K. M. Lim, D. Yu, H. G. Park, Y. G. Choi and C. M. Lee, "Transfer pathway of $^{54}Mn$, $^{57}Co$, $^{85}Sr$, $^{103}Ru$ and $^{134}Cs$ in rice and radish plants directly contaminated at different growth stages," Annals of Nuclear Energy, 29, pp. 429-446 (2002). https://doi.org/10.1016/S0306-4549(01)00048-2
  15. 이한수, 최희주, 강희석, 유동한, 금동권, 임광묵, 박효국, 최용호, 이창우, "요오드의 배추에 대한 침적," 대한방사선방어학회지, 29, pp. 173-177 (2004).
  16. S. Uchida, Y. Muramatsu, M. Sumiya and Y. Ohmomo, "Biological half-life of gaseous elemental iodine deposited onto rice grains," Health Physics, 60, pp. 675-679 (1991). https://doi.org/10.1097/00004032-199105000-00006
  17. 김은한, 최근식, 최상도, 한국원자력연구원 부지 기상정보 종합해석, 한국원자력연구원, KAERI/TR-3753/2009 (2009).
  18. 박종성, 조재영, 이은웅, 조동삼, 변종영, 이석순, 최관삼, 신제 작물생리학, 향문사 (1991).
  19. J. Tschiersch, T. Shinonaga and H. Heuberger, "Dry deposition of gaseous radioiodine and particulate radiocaesium onto leafy vegetables," Science of the Total Environment, 407, pp. 5685-5693 (2009). https://doi.org/10.1016/j.scitotenv.2009.06.025
  20. P. G. Voilleque and J. H. Keller, "Air-tovegetation transport of $^{131}I$ as hypoiodous acid acid (HOI)," Health Physics, 40, pp. 91-94 (1981).
  21. C. A. Pelletier and J. D. Zimbrick, "Kinetics of environmental radioiodine transport through the milk food chain," in: Environmental Surveillance in the Vicinity of Nuclear Facilities, W. C. Reinig, ed., Charles C. Thomas, Springfield, IL (1970).
  22. G. Voigt, "Physical transport and chemical and biological processes in agricultural systems," in: Health Impacts of Large Releases of Radionuclides, Wiley, Ciba Foundation Symposium 203, pp. 3-20 (1997)
  23. International Atomic Energy Agency, Generic Models and Parameters for Assessing the Environmental Transfer of Radionuclides from Routine Releases, Safety Series No. 57, IAEA, Vienna (1982).
  24. K. Heinemann and K. J. Vogt, "Measurements of the deposition of iodine onto vegetation and of the biological half-life of iodine on vegetation," Health Physics, 39, pp. 463-474 (1980). https://doi.org/10.1097/00004032-198009000-00006
  25. H. Mu¨ller and G. Pro ¨hl, "ECOSYS-87: a dynamic model for assessing radiological consequences of nuclear accidents," Health Physics, 64, pp. 232-252 (1993). https://doi.org/10.1097/00004032-199303000-00002