The Effects of Atomic Radiation on Oceanography and Fisheries (1957) / Chapter Skim
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ECOLOGICAL FACTORS INVOLVED IN THE UPTAKE, ACCUMULATION, AND LOSS OF RADIONUCLIDES BY AQUATIC ORGANISMS
ECOLOGICAL FACTORS INVOLVED IN THE UPTAKE, ACCUMULATION, AND LOSS OF RADIONUCLIDES BY AQUATIC ORGANISMS
Pages 69-79
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From page 69... ...
These aquatic organisms may live in either fresh, salt, or brackish water and include vascular plants, algae, protozoans, plankton, all the other invertebrate forms such as aquatic insects, bottomliving crustaceans and molluscs, and representatives of each of the five classes of vertebrate animals. The accumulation and loss of any radioisotope will depend not only upon its own physical half-life but also upon the biological factors that contribute to its incorporation in, retention by, and disappearance from the organism involved.
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From page 70... ...
Certainly this instance can be presumed to represent a chronic exposure inasmuch as the animal was at least two years old and had probably lived in the area during her entire lifetime. Aquatic organisms in the Columbia River below the Hanford Works and those in White Oak Creek, Tennessee, below the Oak Ridge National Laboratory, have all suffered chronic exposures to radiomaterials and have accumulated considerable amounts of those materials in their tissues.
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From page 71... ...
The total dissolved solids in fresh waters ranges TABLE 1 CHEMICAL ABUNDANCES IN THE MARINE HYDROSPHERE mg/1 H 108,000 He Li Be B C N 0.000005 0.2 28 0.5 O 857,000 F 1.3 Ne 0.0003 Na 10,500 Mg 1,300 Al 0.01 Si 3 P 0.07 S 900 Cl 19,000 A K .
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From page 72... ...
are of value for the physical states of elements following the detonation of an atomic bomb, they are at best only suggestive of the steady-state conditions which might result from the continuous spilling of fission product wastes into the sea on a long-term basis. TABLE 3 PHYSICAL STATES OF ELEMENTS IN SEA WATER • (From Greendale and Ballou, 1954)
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From page 73... ...
demonstrated with radioactive iron that a marine diatom assimilated particles of hydrated iron oxide, but that these organisms were unable to take up ionic iron in a complexed form. The first biological experiments in which radioactive atoms were used were performed by Hevesy in 1923.
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From page 74... ...
concentrated radiophosphorus by a factor of 850,000, and that many fresh-water zooplankters concentrated that radionuclide by factors of more than 100,000. Approximate concentration factors for marine organisms are given in Table 4.
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From page 75... ...
have shown that there is a direct correlation between an increase in temperature and an increase in the accumulation of radiomaterials in fishes of the Columbia River, Washington, and of White Oak Lake, Tennessee, respectively. This increase in accumulation is apparently a reflection of the increase in the speed of the metabolic processes with rising water temperatures.
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From page 76... ...
the transport of radiomaterials from one trophic level to another. Problems of the distribution of radionuclides among the trophic levels and the degree of concentration of radionuclides by different organisms can be approached most readily through separate consideration of the effects from an acute exposure and those from a chronic exposure.
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From page 77... ...
These factors of transfer are of particular importance in the event of an acute exposure because the dilution brought about through cell division and growth may well minimize any radiation effect. In any event, there is always a loss in the total amount of radiomaterials in the transfer from one trophic level to another (though not necessarily a decrease in the concentration in individual organisms)
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From page 78... ...
It appears that the particular food web used by any organism is of primary importance in the transfer of radiomaterials from one trophic level to another. Problems for further research One of the fundamental questions to be answered concerns the mechanism of incorporation of the heavier elements, such as the fission products, in aquatic organisms.
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From page 79... ...
1956. Factors controlling the concentrations of thirteen rare metals in sea water.
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