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  • P-ISSN 1225-0163
  • E-ISSN 2288-8985

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    A study of characteristics of cumulative deposition of fallout Pu in environmental samples

    Analytical Science and Technology / Analytical Science and Technology, (P)1225-0163; (E)2288-8985
    2006, v.19 no.1, pp.18-30





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    Abstract

    This paper describes the cumulative deposition of fallout Pu in soil and lichen at the present time and give the characteristics of fallout Pu deposits in the soil. In the soil of the forest, the accumulated depositions of <TEX>$^{239,240}Pu$</TEX> were estimated to be in the range of 34.0 to <TEX>$101.2Bq\;m^{-2}$</TEX> with an average value of <TEX>$65.3{\pm}21.6Bq\;m^{-2}$</TEX>. The average inventory of <TEX>$^{239,240}Pu$</TEX> in the forest was calculated to be two times higher than that in the hill. Also, the deposited activities of <TEX>$^{239,240}Pu$</TEX> in cultivated soil were significantly lower than those in the hill or forest. However, the cumulative depositions of fallout Pu in the volcanic ash soil on Cheju Island were much higher than those in the forest and hill soils. The measured activity concentrations of Pu isotopes in lichens and mosses showed large variations, due to characteristics of species and life span of lichen and moss colonies. From depth profiles, it was found that most of the fallout Pu has been accumulated in upper 10 cm layer of soil. Except for a few cases, the concentrations of <TEX>$^{239,240}Pu$</TEX> in soil tended to decrease exponentially with increasing soil depth. Among parameters affecting the cumulative deposition of fallout Pu, organic substances and rainfall play an important role in the retention and relative mobility of fallout Pu in the soil. However, pH showed a weak correlation with the deposition of fallout Pu in the soil. From sequential leaching experiments, Pu was found to be associated predominantly with the "organic" and "oxy-hydroxy" fractions. Both the activity ratios of <TEX>$^{238}Pu/^{239,240}Pu$</TEX> and <TEX>$^{241}Pu/^{239,240}Pu$</TEX> in soils, lichens and mosses and the atomic ratios of <TEX>$^{240}Pu/^{239}Pu$</TEX> in soils are close to those observed in the cumulative deposit global fallout from nuclear weapon testings. The results obtained from this research make it possible to interpret and predict the behavior of fallout Pu under natural conditions.

    keywords
    cumulative deposition, fallout plutonium, activity ratio, soil, moss


    Reference

    1

    Holm, E, (1975) Health Physics,

    2

    Papastefanou, C, (1989) J. Environ. Radioactivity,

    3

    Sloof, J. E, (1992) J. Environ Radioactivity,

    4

    Thomas, R. S, (1995) Health Physics,

    5

    Jia, G, (1997) J. Radioanal. Nucl. Chem. Article,

    6

    Paatero, J, (1998) J. Environ. Radioactivity,

    7

    McLaren, R. G, (1973) J. soil Sci.,

    8

    Lu, K, (1981) Plant and Soil,

    9

    Schüttelkopf, H, (1981) Development of an analytical procedure for the determination of plutonium in the femtogram-scale and its application to environmental samples (in German),

    10

    Lee, M. H, (1999) Appl. Radiat. Isot.,

    11

    Lee, M. H, (1999) Radiochimica Acta,

    12

    UNSCEAR, (1982) Ionizing radiation: sources and biological effects, UNSCEAR, New York, USA

    13

    Lee, M. H, (1999) J. Radioanal. Nucl. Chem. Article,

    14

    Tuominen, Y, (1973) Absorption and accumulation of the mineral elements and radioactive nuclides, In: The Lichens, Academic Press, New York

    15

    Ellis, K, (1987) J. Environ. Radioactivity,

    16

    Mihok, S, (1989) Health Physics,

    17

    Yamamoto, M, (1981) J. Radiat. Res.,

    18

    Livens, F. R, (1988) J. Environ. Radioactivity,

    19

    Alberts, J. J, (1989) J. Environ. Radioactivity,

    20

    Pavlotskaya, F. I, (1991) J. Radioanal. Nucl. Chem. Article,

    21

    Baeza, A, (1995) Radiochimica Acta,

    22

    Malcolm, E. C, (1984) Health Physics,

    23

    Schimmack, W, (1991) Sci. Total Environ,

    24

    Lee, M. H, (1997) J. Environ. Radioactivity,

    25

    Lee, M. H, (2000) J. Environ. Radioactivity,

    26

    OECD Nuclear Energy, (1981) NEA Group of Experts, The Environmental and Biological Behavior of Plutonium and Some Other Transuranium Elements, Paris

    27

    Lee, M. H, (1996) J. Radioanal. Nucl. Chem. Article,

    28

    Murdock, R. N, (1993) Environ. Sci. Tech.,

    29

    Perkins, R. W, (1980) World wide fallout. In: Transuranic Elements in the Environment, DOE/TIC-22800, National Technical Information Service, Springfield

    30

    Yamamoto, M, (1990) J. Radioanal. Nucl. Chem. Article.,

    31

    Hötzl, H, (1987) Radiochimica Acta,

    32

    Paatero, J, (1994) J. Environ. Radioactivity,

    33

    Krey, P. W, (1975) Mass isotopic composition of global fallout plutonium in soil, IAEA-SM-199/39

    34

    Harley, J. H, (1980) J. Radiat. Res,

    35

    Hirose, K, (1995) J. Radioanal. Nucl. Chem.,

    36

    Lee, M. H, (2005) Environ. Sci. Technol.,

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