Radiation sickness, often known as Radiation poisoning or radiation injury arises out of accidental or occupation related excessive/bulk exposure to any kind of ionizing radiation. A very commonly sighted example of radiation induced sickness could be the atomic bombings of Hiroshima and Nagasaki, Japan. This article intends to provide a broad information in relevance to radiation sickness and it’s features,
Ionizing radiation consists of: gamma rays, X Rays, neutron/photon/ meson beams etc. The accidental exposure falls under acute exposure which usually occurs due to nuclear power accidents/ radiation mishaps and occupation associated exposure falls under chronic radiation exposure. Also, therapeutic exposure to radiation used to treat many varieties of cancers contributes towards radiation sickness. Ionizing radiation is believed to produce long term harmful effects in body. This is due to the chemical changes that the ionizing radiation is capable of producing in body on human body tissues.
The symptoms of radiation sickness depend upon the amount/ dose of exposure, your distance from the source of radiation, the kind and strength of radiation. The part of body exposed to radiation also defines the type and severity of symptoms as, different tissues have different sensitivities. Long term or chronic side effects include, premature ageing and susceptibility towards development of cancers in body. The most sensitive to radiation injury are the fast multiplying cells in the body that include the skin, mucous membrane, reproductive parts, gastro intestinal tract and bone marrow. Unborn babies and infants who are in growing stages are very susceptible to radiation sickness too. Pregnant women exposed to radiation might give birth to still birn babies or the babies might show multiple deformities on birth. There is a direct correlation between the amount of exposure and severity and onset of symptoms. The higher the dose of radiation received, the earlier the symptoms appear.
Studies have shown that an total absorbed dose of 1gray (unit of radiation) or more is believed to start producing symptoms of radiation sickness. A total dose of 6 gray or more leads to serious damage that is often untreatable and might result in death. The symptoms are non specific and might seem unrelated to radiation exposure that is why, it is very important to identify them.
In Acute Exposures To Radiation, Usually As An Outcome of Accidents, The Following Manifestations Can Be Found:
- Nausea, dizziness and repeated vomiting. These are the earliest symptoms and it is considered bad if these appear very soon as this indicates a very high absorbed dose of radiation.
- Repeated loss of fluid through vomiting and Diarrhea can lead to dehydration. There might be passage of blood in vomiting and stools.
- Extreme Fatigue, weakness and fainting making it difficult to carry out even day to day activities with ease.
- Deterioration of mucous membranes and skin leading to mucositis and dermatitis. Very often, we can find ulcers, especially in oral cavity, food pipe, stomach and intestines. There can also be redness, soreness, friability and easy bruising of skin. There might be a red sun burn like rash or a purple, purpuric rash on skin. There might also be development of blisters called as cutaneous radiation syndrome.
- Due to low platelet counts, there is an increased tendency to bleed from nose, gingiva, rectum and oral cavity. There might also be internal bleeding.
- There is often hair loss, too.
- There is accompanying fever.
- Low blood pressure.
- Delayed/ poor wound healing.
- The white blood counts often fall leading to a person growing more prone towards infections.
- Various investigations that make use of dosimeters, radiation badges, differential and total blood cell counts etc are applied to identify the degree of absorbed dose of radiation.
Treatment of Radiation Damage
To relieve the ill effects of radiation sickness, the treatment is more or less symptomatic and supportive. It is not really possible to reverse the effects of radiation damage. However, there are certain substances that can be used to reduce the damage to internal organs. To sight a few examples,
- Potassium iodide is used to reduce the damage caused to the thyroid gland due to the absorption of radio iodine.
- Prussian blue helps in eliminating cesium and thallium from the body.
- Likewise, a substance called Diethylenetriamine pent acetic acid (DTPA) binds to radioactive metal particles like plutonium, americium and curium and helps in clearing them out from the body, partly, if not totally.
- Certain proteins and protein based medications (granulocyte colony-stimulating factor, filgrastim and pegfilgrastim ) that increase the production of white blood cells in the bone marrow can be used to reduce the risk of infections.
- Blood transfusions, Iron and vitamin supplements might be required to tackle the associated anaemia.