c. Extensive animal data has established that radiation exposure produces an
acceleration of the aging process. This effect is quite apart from any specific disease
manifestation. The animal simply ages faster and dies sooner from causes
indistinguishable from those of nonirradiated animals. As with carcinogenesis, no
threshold is apparent.
d. As early as 1927, it was reported that radiation increases the rate of
mutations in the fruit fly. This work has since been confirmed in other species. As
further evidence of the difference in species' resistance to radiation, it has been shown
that the mutagenic effect is ten
times greater in the mouse than in the fruit fly for a given radiation dose. Obviously,
there is very little human data regarding radiation-induced mutations. However, the
following biological facts provide sufficient evidence to warrant concern:
(1)
Mutations are transmitted to succeeding generations.
(2)
Mutations may be dominant or recessive.
(3)
Mutations may eventually result in a genetic line dying out.
(4)
There is no threshold dose for the genetic effects of radiation
(5)
Any exposure may be accompanied by the production of some.
(6)
The number of mutations is proportional to the dose.
e. Direct exposure of the gamete or zygote may occur during x-ray examination
of the parent. Indeed, any exposure during the first trimester (first 3 months) of
pregnancy MAY carry the penalty of an abnormal child. Chromosome activity is at its
maximum in early pregnancy. It has been determined on numerous occasions that
therapeutic doses of radiation to the pregnant woman can even produce fetal death.
The degree of abnormality varies roughly in proportion to dose rates and exposure time,
but there is as yet insufficient evidence to establish a minimum threshold dose for
humans.
f. Fertility effects are a grossly overrated radiation effect. True, radiation is
capable of reducing fertility--the amount of reduction being dependent upon the dose.
However, except for direct, intentional exposure to the gonads, no radiation
environment in peacetime is expected to be high enough to cause sterility, either
temporary or permanent.
g. Irradiation of the eye has been shown to result in cataract formation (lenticular
opacity), which appears some time after exposure by x- or gamma rays.
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