Dose calculations. The Moss (Moss 1988) factors in Table N.12 2,
supplied through the courtesy of Dr. E. T. Lessard of Brookhaven, permit
the calculation of plutonium-239 oral intake from urinary excretion, or
vice versa. The facters vary about 3-fold in the present case where the
periods of exposure are from about 5 to 25 years.
Of the 104 cases in Table N.12 #1, all had lived on Rongelap since
birth or for at least 7 years with four exceptions. One other exception
was the case of a 12 year-old female who first arrived in 1980; her
output of 2.34 pCi/d was practically identical to that of an 11 year-old
(2.18 pci/d) who had always lived on the island.
For orientation,
let us use a factor of 1.5 x 10-4, corresponding to
about 7 years of plutonium exposure. Then for the maximum urinary
output, the intake would be 38 pci/d { (5 x 10-9) / (1.5 x 10-4) J.
The corresponding whole-body dose (30 year) would be 1.5 rem for
plutonium-239, and 3 rem for the three transuranics.
(The corresponding
Livermore diet estimate would be .014 rem.) Three rem of course, is
relatively a sizable dose. However, it is of interest that when combined
with the rest of the Brookhaven estimates, the total dose of
ren does
not exceed the 5 rem limit. For exposure from birth to age 30 years, the
dose would be 1.63 times greater (Table 4.4 #1).
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