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BIOLOGY AND MEDICINE
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UNCLASSIFIED
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(5) Genetic effects. No anomalies have been noted in the 13 babies born |
of irradiated parents since exposure. One possible exception might
be the stillborn child of a woman in the original group of irradiated _.
Rongelapese examined. It is not known whether the mother was irra- EM
diated before conception or early in pregnancy.**
~
b. Beta lesions .
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Gross and microscopic studies of ‘residual skin lesions revealed no ~
changes in the skin indicative of premalignant or malignant change.
1
c. Internal radiation
Radiochemical analyses of urine samples‘and whole-body gamma.
ve
spectroscopy for cesium 137 revealed levels ofthis isotope. several times |
higher than found in Americans, but far below accepted “tolerance”levels.
Because of subsequent worldwide fallout, residue of the original exposure ~
was difficult to differentiate from later absorption. Strontium 90 levels as
"of March 1957 were far below “tolerance”levels. The. body burden of =.
isotopes had dwindled rapidly over the 3 years sinceexposure and was
¥
not ‘
considered to present any long-term hazard.
1
|
”
The levels of contamination on Rongelap Atoll were reduced sufficiently to allow safe habitation, and the Rongelap people were moved back to their home island in June 1957.
Future examinations of the Marshallese will include studies of (1), subacute radiationef- 7
fects, (2) long-term effects of radiation on the human being,and (3) careful ecological radia- —
tion studies of the people, particularly studies of the‘soil-food-human chain for the
¢ radioisotopes still present onn the island.
CONFERENCE ON BIOLOGICAL EFFECTS OF COSMIC RAYS.
A conference on.the biological effects of cosmic rays was held at the Donner Laboratory
of the University of California, January 21-22. The AEC’s growing interest in this subjectstems from the possible similarity of damage from cosmic radiation to damage from other
types of radiation. The conference reviewed the present state of ‘knowledge about the nature
whether the dense tracks produce unexpectedly severe effects, especially in the central
nervous system. Biological studies of the somatic and genetic effects of decelerating heavy
‘particles could be adequately pursued under laboratory conditions, using availableaccelerators. Another important aspect of any effects studies undertaken would be the dosimetry of
cosmic rays at extremely high altitudes. Measurements taken thus far at very high altitudes
and corrected to the zero pressure that occurs at the top of the atmosphere indicate low
dosages of approximately 25 millireps per day at thee top of the atmosphere.
BACKGROUND RADIATION STUDIES
a
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Heightened interest in the radiation received by man from natural radioactivity. has been
stimulated by the assumption of many geneticists|that thereis a linear relationship between
“Reported in “Some Effects of lonizing Radiation on Human Beings, ” U.S. Atomic Energy:Commis- °
sion, July 1956,
UNCLASSIEIED
— a eese at
of cosmic radiation, acknowledged the dearth of data on biological effects, and discussed the —
kinds of data needed. A research program in which the AEC might have an interest would be.
aimed at elucidating biological indicators of the damage resulting from the very dense ionization of rapidly decelerating heavy particles. Also of interest would be studies to'determine