Normal chest examination
Normal dental examination
Rib cage examination 140
Gall bladder examination 170
Barium enema examination 500
*Variations by a factor of 2 (above and
below) are not unusual.
Nuclear medicine procedures tend to deliver even higher doses.
Any individual whose official duties or authorized
activities include handling, operating or working in the presence of any type
of radiation source or radiation producing device is a subject to occupational
Types of radiation exposure
radiation exposure involves low
levels of ionizing radiation over a long period of time. Among the possible effects of chronic
exposure are the increased risk of developing delayed somatic effects such as cancer
and cataracts. Also, research indicates
possible genetic effects in humans from radiation damage to sperm and egg
cells. Genetic damage may result in
birth defects passed
along to future generations.
- Somatic effect
is the biological effect that occurs on the exposed individual.
mutation of their genetic materials.
- Genetic effect
refers to biological changes on the descendants of the exposed individuals due
effect is a genetic effect that is inherited or passed onto an offspring.
- Teratogenic effects are birth defects, experienced when an embryo or fetus is exposed to large doses
of radiation. Radiation
induced genetic abnormalities have not been identified in human
populations. However, they have been observed in less genetically
Acute radiation exposure is delivered
in a short period of time. Larger acute
exposures are often associated with deterministic effects. The following
possible outcomes can be produced as a result of a large acute exposure:
25 - 100 rads
Minor blood changes, some illness anticipated
100 - 300 rads
Illness (lowering of the white blood cell count,
nausea, bacterial infections, vomiting, loss of appetite, diarrhea, fatigue,
hair loss, and possible sterility), at the end of this range death may occur but this is infrequent and would be associated
with those individuals undergoing simultaneous physiological stress. These are the
classic signs and symptoms of the radiation sickness syndromes.
300 - 450 rads
Anticipated death of 50% of
population within 30 days, if medical assistance is not provided. Death
caused by complications associated with radiation sickness syndromes.
When severely exposed, the victim may suffer fever,
abdominal pains, explosive diarrhea, internal bleeding, infection, shock,
convulsions, coma, and ultimately death.
Acute exposure delivering 300 rads and above in a short period of time
could possibly produce these outcomes.
is a term that describes how sensitive a given cell is to radiation
Scientists have found that the rate of mitosis and the degree of
cellular differentiation determine radiation sensitivity.
The possible effects that could occur due to radiation
exposure to cells are:
The following cells are considered to be the most
radiosensitive because of their reproductive rate:
- There is no
- Cells repair
the damage and operate normally and/or cannot reproduce.
- Cells are
damaged and operate abnormally.
- The cells die
as a result of the damage.
Those, which reproduce slowly and are considered the least
radiosensitive are nerve, muscle and bone cells. Of course, radiation affects each person
differently depending on such factors as total dose, dose rate, type of
radiation, the area of body exposed, cell sensitivity, individual sensitivity,
age, medical history, and physiological condition.
- Cells of the
- Blood and
blood producing organs.
- Immature white