Understanding Radiation Exposure
What are the effects of radiation exposure on the human body?
At this time, the effects of radiation exposure on the human body are cause for concern, because of the radiation released from the nuclear plant in Japan, the direct result of the natural disaster that occurred on March 11, 2011.
While most people have basic knowledge about radiation and are familiar with some of the effects of radiation exposure on the human body, they may not be aware of the long-term effects, the future implications, or the effects of different levels of radiation exposure.
What level of radiation exposure causes damage to the human body?
Atomicarchive.com (1) gives a brief description of what happens to the human body, when exposed to different levels of radiation.
What areas of the human body are adversely affected?
These include the hair, brain, thyroid, blood system, heart, gastrointestinal tract and reproductive tract.
The following information, offers a brief synopsis of what happens to the human body at different levels of radiation exposure.
Hair: 200 rems or higher radiation levels result in clumping and rapid hair loss.
Brain: Brain damage occurs to brain cells at 5000 rems or greater. Note that radiation causes damage to nerve cells and small blood vessels, which results in seizures and immediate death.
Thyroid: Radioactive iodine can destroy all or part of the thyroid gland; but the effects diminish with potassium iodide.
Blood system: At 100 rems, the lymphocyte cell count drops rendering a person more prone to infection. This occurs in radiation sickness.
Heart: 1000 to 5000 rems damages small blood vessels, leading to heart failure and death.
Gastrointestinal tract: 200 rems or more causes damage to the intestinal tract lining, which results in nausea, bloody vomiting and diarrhea.
Reproductive tract: At 200 rems, rapidly dividing cells suffer damage. Over the long term, radiation sickness results in sterility.
DNA and RNA: 200 rems harm DNA and RNA. (2)
To understand this more fully, it is important to understand the meaning of the word rem.
“The roentgen equivalent in man (or mammal) or rem (symbol rem ) is a unit of radiation dose equivalent. It is the product of the absorbed dose in rads and a weighting factor.” (3)
To simplify this statement, rem is a unit of radiation. The following information will help to put this in proper perspective.
“An acute whole-body dose of under 50 rem is typically subclinical and will produce nothing other than blood changes. 50 to 200 rem may cause illness but will rarely be fatal. Doses of 200 to 1,000 rem will probably cause serious illness with poor outlook at the upper end of the range. Doses of more than 1000 rems are almost invariably fatal.” (4)
It is important to understand how the radiation used in the medical realm differs from the kind of exposure that people may have with respect to the potential nuclear disaster in Japan.
Are human beings at risk when treated with radiation?
Remember that there is always some degree of risk associated with any level of radiation exposure, but there is a marked difference in the radiation exposure levels. To understand radiation exposure in the medical realm more fully, let us look at what happens when a person undergoes medical x-rays or treatment with radiation.
“A rem is a large dose of radiation, so the millirem (mrem), which is one thousandth of a rem, is often used for the dosages commonly encountered, such as the amount of radiation received from medical x-rays and background sources.” (5)
It is always important to keep things in proper perspective, particularly when talking about radiation. Again, being knowledgeable is preferable to being non-knowledgeable, particularly with respect to different aspects of the effects of radiation on the human body.