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Radiation therapy
 
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Radiation sickness

Alternative names:

radiation poisoning

Definition:

Symptoms and illness resulting from excessive exposure to radiation, whether that exposure is accidental or intentional (as in radiation therapy). The term also includes side effects of exposure to radiation.

Considerations:

Radiation is normally divided into ionizing and nonionizing types. Nonionizing radiation is familiar as light, radio waves, microwaves and radar; types of radiation which generally do not cause tissue damage.

Ionizing radiation is radiation that produces immediate chemical effects (ionization) on human tissue and includes X-rays, gamma rays, and particle bombardment (neutron beam, electron beam, protons, mesons and others). This type of radiation can be used for medical testing and treatment, scientific purposes, industrial testing, manufacturing and sterilization, weapons and weapons development, and many other uses.

Radiation sickness results when humans (or other animals) are exposed to excessive doses of ionizing radiation. Radiation exposure can occur as a single large exposure (acute) or a series of small exposures spread over time (chronic). Radiation sickness is generally associated with acute exposure and presents with a very characteristic set of symptoms that appear in an orderly fashion. Chronic exposure is usually associated with delayed (often by many years) medical problems such as cancer and premature aging.

The degree of illness (acute radiation sickness) is dependent on the dose and the rate of exposure.

As a rule
Total body exposure of 100 roentgens causes radiation sickness.
Total body exposure of 400 roentgens causes radiation sickness and death in half the individuals.
100,000 rads causes almost immediate unconsciousness and death within an hour

The severity of symptoms and illness depends on the type of radiation, the amount of radiation, the duration of the exposure, and the body areas exposed. Symptoms of radiation sickness usually do not occur immediately following exposure. Because it is difficult to determine the amount of radiation exposure from accidents, the best indications of the severity of the exposure are: the length of time between the exposure and the onset of symptoms, the severity of symptoms, and severity of changes in white blood cells.

Children who receive radiation treatments or who are accidentally exposed to radiation will be treated based on their symptoms and their blood cell counts. Frequent blood studies are necessary and require a small puncture through the skin into a vein to obtain blood samples.

Causes:

Accidental exposure to high doses of radiation, such as in certain occupations, or exposure to excessive radiation for medical treatments (may include excessively high doses, excessive time of exposure, or excessive body areas exposed).


Adam

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