BEEER BEERES
57
phantom which has been loaded with the radionuclides in que stion.
Obviously, the whole~body counter comes closest to giving : direct
measurement of the body-content. The collected data obtaineH with it
are presented in Tables N.7, #1, #2, and #3.
In the case of radionuclides that emit beta rays (strontfium-90 or
alpha particles (transuranics), whose range in tissue beforp
absorption may be at most a centimeter or so down to some
micrometers, another method must be used. Recourse is had fo
measuring the daily radionuclide excretion in the urine.
The body
content is then calculated from knowledge of the metabolism of the
radionuclide in question. This method is not as reliable =
whole-body counting. Fortunately in the present case the datection
of strontium and the transuranic elements is not as important as the
detection of cesiun.
the metabolism of the radionuclide than would be the case :
The Livermore results are based on this method.
Conversely, knowing the daily urinary output of a rad
it is possible to calculate the daily intake by ingestion. For
example, based on the work of Jones et al (1985), Skrable é¢ al
(1987) and Moss (1988), Dr. E. T. Lessard of the Brookhaver
Laboratory has calculated the factors for plutonium-239 give
Table N.4 # 4. When the daily intake is multiplied by the
the urinary output is obtained. Conversely, when the urin:
is known, dividing it by the factor will predict the daily fi
The Jones and Moss alternatives are offered; at 20-30 year
constant diet, they differ by a factor of 1.75.
I used the
Moss-based factor for the calculations used in the text, Sé
4.3, because it corrects for earlier errors in the data badge which
Jones did not know about.
(Cont.)
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