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statistically significant difference in the number of mutations
“t
in the offsprings of irradiated parents as compared with offsprings of non-irradiated control parents,
It did not prove in
any sense of the word that there was no genetic effect,
Following a general discussion of the mechanisms of genetic
change especially as produced by radiation, both natural and
artificial, the committee made certain recommendations, In doing
so they used natural background radiation exposure (i.e,, radiation from cosmic rays, igneous rocks, radium and radtopotassium
in our bodies, etc.,) and the so-called spontaneous mutation
rate as base lines,
In addition they were unanimous that no
increase in the spontaneous mutations rate was desirable and that
all radiation exposure to the germcells at whatever rate of
exposure did indeed increase the mutation rate in proportion to
the total exposure received at the time of conception,
Consequently
they stated that all radiation exposure to the gonads was
detrimental and consequently radiation exposure should be kept
at the minimum consistent with the over-all needs of a society.
They then observed that half of the American children were
born of parents approximately 30 years of age or less,
They
noted that by the age of 30 the average American would receive
germ cell exposures as follows:
1, Background or natural radioactivity
3x
2, Medical x-rays
36r
3. Fallout from weapons testing if continued
at rate for the past 5 years
O,1ir (0,02
to 0,57)
They then estimated that the exposure necessary to double
the mutations rate in humans lay between 52 and 150r, more likely
30r to 80r, but also that different gene loci were quite different
in thelr sensitivity to radiation,
Taking these observations into
consideration they felt that if the population as a whole were to
~~
Enclosure IT
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