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drinking water supplies would be principally in soluble form.
The water
collected fram a well and a cistern on the Island of Rongelap (Table Three)
about 21 months after the March 2, 1954 fallout, was found to have about
80 percent of the activity in the filtrate, but there was an undetermined.
amount that settled to the bottom.
Other data suggest the material to have been
about 10-20 percent soluble in water.
In the event contaminated food is ingested it is possible that the
total activity--soluble and insoluble--may find its way into the gastrointestinal tract since at times immediately following a fallout most of this
activity probably would come from the surface contamination rather than the
soil-plant-animal cycle.
There may then follow some solubilizing in the
acid stomach with subsequent removal from the tract before reaching the
lower large intestine.
.
It is assumed for these calculations that (a) 90% of the fallout
material is insoluble when computing doses to the gastrointestinal tract,
and (b)
that the isotopes of iodine, strontium, and barium are all soluble
when computing doses to the thyroid and to the bones.
These assumptions are
probably conservative, i.e. they may overestimate somewhat the radiation
exposures.
B.
Biological Significance.
DOE ARCHIVES
After the estimation of radiation doses by any procedure the final
step is an evaluation in terms of biological effects both for short and
Jong terms.
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