BBC News
Thursday, September 30, 1999
Health: Medical notes
Radiation sickness factfile
Exposure to radiation can cause devastating damage to the immune system and to the tissues of the body. The effects are known as radiation sickness or syndrome. Radiation can also cause little understood changes to the body's genes, which can be manifested through the development of diseases such as cancer later in life, and possibly as birth defects in future generations.
What does radiation do to the body?
Radiation causes atoms, the basic building block of the body's cells, to become electrically charged which can be potentially dangerous to the body is generated at abnormally high rates.
Natural background radiation causes only low levels of damage which can be repaired by the body.
However, when the body is exposed to unnaturally high levels of radiation it cannot combat the damage caused.
Among the cells that are most sensitive to radiation are those that line the intestine (crypt cells), white blood cells that fight infection and the cells that make red and white blood cells.
The impact on these cells leads to the classic early symptoms of radiation sickness.
For instance, damage to the intestine cells stimulates
nausea, vomiting and dehydratation.
Radiation penetrates the body and is wholly or partially absorbed by soft and hard tissue.
Radioactive fallout in the form of particulate matter can be swallowed or breathed in.
What are the symptoms?
There are many symptoms of radiation sickness, and their severity varies greatly depending on the dosage. The initial symptoms include:
Nausea
Vomiting
Diahorrea
Fatigue
These symptoms may be followed by:
Headache
Shortness of breath
Rapid heartbeat
Inflammation of the mouth and throat
Worsening of tooth or gum disease
Hair loss
Dry cough
Heart inflammation with chest pain
Burning
Permanent skin darkening
Bleeding spots anywhere under the skin
Haemorrhage
Anaemia
In severe cases, where the radiation exposure has been severe - approximately 10 gray (gray are measures of radiation) or more - death may occur within two to four weeks.
Those who survive six weeks after the receipt of a single large dose of radiation to the whole body may generally be expected to recover.
What treatment is available?
Anti-nausea drugs and painkillers can be used to relieve symptoms of radiation sickness. Antibiotics may also be needed to fight off secondary infection.
Blood transfusions may be necessary for patients suffering from anaemia.
What is the long-term health impact?
Radiation-related illnesses tend to show themselves about 10 to 15 years after a radiation disaster.
The body's endocrine, or hormone-secreting, glands appear to be particularly sensitive to radiation.
It is now widely accepted that the Chernobyl nuclear disaster has led to a massive increase in thyroid cancers in the three countries most affected.
Already, 680 cases of thyroid cancer have been recorded in Belarus, Russia and Ukraine. Belarus has shown a 100-fold increase, from 0.3 per million in 1981-85 to 30.6 per million in 1991-94.
Unicef has noted significant increases in many types of health disorders in Belarus since the disaster.
For example, problems of the nervous and sensory organs have increased by 43%; disorders of the digestive organs by 28%; and disorders of bone, muscle and the connective tissue system have increased by 62%.
The Ministry of Chernobyl in Ukraine estimates that those people living in contaminated areas are twice as likely to suffer from disease as people from clean areas.
What about future generations?
Scientists studying victims of the Chernobyl disaster have discovered that radiation-induced genetic mutations can be passed down from generation to generation.
Genetic mutations appear to occur twice as often in the children of families exposed to radioactive fallout and represent permanent damage to the DNA that is passed down through the generations.