logical effects of a numberof fission products have been studied in animals by Hamilton,’
Abrams,! Bloom,’ and others. However, most of these studies do not cover the problem of the
long-term effects produced by small amounts of internally deposited isotopes in animals.
Few data are available concerning the effects of internal contamination with mixed fission
products from nuclear detonations. Contamination is not produced by every detonation of a
nuclear device, For example, no internal contamination was detected in any of the individuals
exposed to the airbursts at Nagasaki and Hiroshima.
In field tests of the contaminating type of atomic detonation, animals that inhaled fission
products during short periods of exposure were found to have insignificant amounts of internal
contamination.
The long-term effects (primarily malignant changes) resulting fr>m radium deposition
have been used to set the limits for maximum permissible body concentrations of various
radionuclides.’ The maximum permissible level of a radioisotope is the maximum amount
which may be deposited in the body without the production of detectable damage. The value
for both internal and external irradiation to any tissue is 0.3 rem/week.
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