The risk factor for first generation genetic defects is smaller than
that for cancer mortality (National Academy of Sciences, 1972:
NCRP,
1987a), being approximately 1 x 10-4.
Furthermore, since no genetic
effects have been recorded as yet for the Japanese (Radiation Effects
Research Foundation, 1987),
(b)
Transuranics.
it is unlikely that any would be found here.
The Brookhaven dose estimates vary
Significantly, reflecting the transuranic data which may vary by a factor
of 1,000. Could this be “real"? Probably not. To supply the
transuranic oral input necessary to maintain the maximum urinary output
recorded, it would be necessary to eat 5 kg of clams every day -- or even
larger amounts of other foods.
Obviously,
something is radically wrong,
technically or
physiologically. Contamination is one possibility (urine collection in
the Marshalls is difficult). Or conceivably, an inborn error of
metabolism allows certain individuals in the general population to absorb
100 times as much from the gut as that which the ICRP recognizes as
normal.
It is therefore essential, as emphasized in the Preliminary Report,
that the problem be studied immediately.
As a start,
additional urines
should be collected repeatedly from the same individuals under rigorously
controlled conditions to determine the reproducibility of results, and
which simple changes in life style might affect them.
{c)
Infant dose.
The question of infant and childhood dosage has
been raised, and is a sensitive issue.
months 0-12 appears to be 0.1 rem.
The maximum internal dose for
More information should become
available by October. According to the ICRP tables, the dose per unit
intake is 2 - 3 times higher for small children than for adults, but
children eat less so that the two factors tend to cancel one another out.
In any case,
the observations thus far should not give rise to alarm, but
they must be followed up.
(d) The foregoing comments apply to the future. But what about the
influence of the past? The Rongelap residents exposed to the Bravo shot
received an acute dose of 190 rem in 1954; during 1957-1978 they
received a chronic dose of 3 rem. My opinion is that the addition to
these past doses of something like 3 rem during the next 30 years will
not appreciably increase detectable health and genetic risks in a way
that should preclude return to Rongelap Island.
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