Evening star. [volume] (Washington, D.C.) 1854-1972, 1957-05-05
BY WILLARD F. LIBBY

Ever since its nuclear testing activities began,
the United States Atomic Energy Commission has
been aware of the Importance of investigating the
possible effects Of radioactive fallout and of deter
mining how much fallout radioactivty has been
produced by nuclear tests
Particularly in recent years. great amount of
information has been amassed by the commissions
studies Literally hundreds of thousands of dust
samples, and thousands of samples of soil, plants
milk, other food products and bones have been COL
lected in this country and in other parts of the
world, and have been analysed for radioactivity.
AS a result, good information is available on
the amounts of radoactivity which have been de-
posted falout the upake of falout radioactivty
into plants, animals, and human beings and the
rate of descent of the radioactive particles from
the shakespeare.
There is less certainty about the magnitude Of
the biological effects which might be expected from
test fallout, and probably this cannot be stated in
precise numerical terms at this time Nevertheless
among those scientists who have studied the ques-
ton there is general agreement that fallout radia-
ton exposures at the present rate of testing are
far too small to result In observable effects among
the population
The Two Hozords
There are two possible hazards from fallout
radoactivity One the genetic hazard due to radia
ton Of the reproductive organs by penetrating gam
ma radiation. The other is the hazard to health
due to irradaton of the bones by strontiu 80 taken
up in food and deposited in the skeleton The mag
nitude of both these possible effects depends upon
the amount of radiation exposure
The conclusion that the actual risk from test
fallout is small is based upon the following prin-
cipal reasons:
I The radiation exposures from test fallout are
- very small compared with the radiation ex-
poSures which living things receive, and always
have received, from cosmic rays from outer space
and from the radioactive materials naturally present
in the SOIL air, water, plants and animals and even
in our own bodies.
= The radiation exposures from test fallout are
- far below the permissible amounts of radiation
which have been recommended by the most authori-
tatve scientific groups, in this country and other
countries for exposure Of the public.
Natural radiation exposure is called the radia-
ton background Background levels differ from
place to place. They are above normal in areas
where uranium or thorium minerals are close to
the surface They also increase with altitude, be-
cause of an increased effect Of cosmic rays. These
differences In natural exposure from locality to To-
cality range up to amounts 100 times greater than
the exposures which have resulted from test fallout
Some Comparisons
To be more specific, present strontium go levels
produce dosage to new bone, such as that formed
which a resident at sea level would receive from
cosmic rays If he moved from beach to the top
of hill few hundred feet high The external
dosages from fallout, that is, those which might
cause genetc effects, have been about or to about
per cent Of the dosages from natural radiation
In certain parts of the world, brick or concrete
block houses may contain enough radioactive ma
tera to expose residents to considerably radia-
ton than persons living in wooden houses These
additional dosages may range from to 100 times
the dosage due to test fallout.
What about future nuclear tests? without going
into detail, it can be demonstrated that even II
tests were to continue at the present rate for dec
AIDES the exposures from faout still would be small
in comparison with the exposures from natural
radioactivity.
No scientist maintains that there is no risk at
all from test falout. What the data show is that
the risk is extremely small compared with other
risks which are part of everyday life We must
weigh this risk against the risk to ourselves, our
freedoms, and the safety Of the whole free world
should we abandon tests before achieving an efec-
tive system of safeguarded disarmament.