790
GUSTAFSON, BRAR, AND MUNIAK
years of decreased '*'Cs intake would the !°"Cs in bone begin to amount
to an appreciable portion of the whole-body content.
SUMMARY
In summary, an empirical relation between airborne radioactivity
and deposition has been found which has been verified by direct soil
measurements. The influence of fallout rate rather than fallout accu-
mulation on plant and animal uptake is apparent. Milk was found to be
the most important single dietary contributor of Cs after the resumption of nuclear testing in 1961. The fivefold increase in dietary
level between 1961 and late 1963 has been matched by a similar in-
crease in whole-body burden with atime lag of some six to nine months,
Some '*’Cs has been shown to be incorporated in bone, but its relative
radiobiological importance is minimalat this time.
REFERENCES
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co ©
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