The
individual risk from the medical use of X-rays must be evaluated against the
potential seriousness of the conditions for which they are properly indicated.
There is, however, another major danger from ionizing radiation that of
damaging the gonads (testes and ovaries) and creating harmful mutations of the
genes that transmit hereditary characteristics. Geneticists strongly advise
against provoking any gene mutations beyond those produced by natural
background radiation.
While
some geneticists would still argue the point, the present consensus is that the
risk of any given individual having a child with inborn defects is not
significantly increased above normal by submitting to the use of safely
shielded X-rays for properly indicated medical or dental needs. The amount of
theoretical harm done by correctly administered X-ray dosages is so small that
it has never actually been detected or measured. Properly given dental X-rays
involve such a limited area of the body that they contribute negligibly to
whole body or gonadal radiation.
Nuclear
Weapons Atomic fallout risk
The
third source of radiation hazards to which the human race is now exposed came
into existence in 1945 with the first atomic bomb. Since then there has been
great scientific, popular, and political furor over the legitimacy of testing
or using such weapons. The explosion of an atomic weapon above the surface of
the earth creates an atomic fall out, creating dangers that by their very
nature are beyond the control of exposed persons. A particular problem is posed
by the long lived isotope strontium 90, chemically similar fit to calcium.
Blown into the atmosphere and later
descending to earth, this isotope could be absorbed by plants and passed on to
man in meat, milk, and other foods. In the human body it would tend, like
calcium, to lodge in the bones and might therefore damage the blood-forming
organs and produce leukemia especially in children. The reality of this the
cortical risk is constantly being evaluated For example, the U. S. Public
Health Service has expanded to every state its program measuring the kinds and
amounts of radioactivity in the meals of selected school children. These
regular diet studies permit more accurate estimates of the daily intake of
radio active substances by children and young adults.The Federal Radiation Council, in a
report issued in May, 1963, stated:
Liodine
131 doses from weapons testing conducted through 1962 have not caused undue
risk to health. "Health risks from present and anticipates levels of
strontium 90 and from fallout due to
testing through 1962 are too small to justify measures to limit the
intake by modification of the diet or altering the normal distribution and use
of food." In May 1964, John D. Harley, Ph. D., of the U. S. Atomic Energy
Commission pointed out that natural radioactive isotopes (background radiation)
give Americans a bigger dose of radiation every year than arrives through
radioactive fallout, although the dose from fallout is a "significant
fraction" of the natural dose.
The
greatest potential problem of radioactive contamination, if the problem goes
uncontrolled, lies in the continuing development of atomic energy. A U. S.
Public Health Service committee estimated that the accumulated volume of
radioactive wastes will increase from about 1.5 million gallons in 1965 to 2
billion gallons in 1995.
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