Concern about the use of the toxin ricin as a terrorist weapon have surfaced
following media reports of isolated findings and poisonings related to this
substance. Ricin is a naturally occurring toxin that is found in castor beans. Ricin poisoning may occur from chewing and swallowing castor beans, and the
toxic substance can also be obtained the waste material that remains after
processing castor beans to produce castor oil.
Ricin can take many forms: It can be a powder, a mist, a pill or pellet, and
can be dissolved in water and other liquids. This means that a person can
contract ricin poisoning via inhalation or ingestion; the initial symptoms of
ricin poisoning depend upon both the degree and route of exposure. Accidental
exposure to ricin unrelated to the ingestion of castor beans would be extremely
unlikely to occur.
If ricin is inhaled, symptoms typically begin within eight hours of exposure
and include difficulty breathing, fever, cough, nausea, sweating, and a feeling
of tightness in the chest. The skin may turn blue due to the decreased oxygenation
of blood resulting from fluid buildup (edema) in the lungs. Low blood pressure
and respiratory failure may ultimately occur.
It would take a deliberate act to make ricin and use it to poison people. Accidental exposure to ricin is highly unlikely.
People can breathe in ricin mist or powder and be poisoned.
Ricin can also get into water or food and then be swallowed.
Pellets of ricin, or ricin dissolved in a liquid, can be injected into people's bodies.
Depending on the route of exposure (such as injection or inhalation), as little as 500 micrograms of ricin could be enough to kill an adult. A 500-microgram dose of ricin would be about the size of the head of a pin. A greater amount would likely be needed to kill people if the ricin were swallowed.
In 1978, Georgi Markov, a Bulgarian writer and journalist who was living in London, died after he was attacked by a man with an umbrella. The umbrella had been rigged to inject a poison ricin pellet under Markov's skin.
Some reports have indicated that ricin may have been used in the Iran-Iraq war during the 1980s and that quantities of ricin were found in Al Qaeda caves in Afghanistan.
Ricin poisoning is not contagious. It cannot be spread from person to person through casual contact.
Low blood pressure, also referred to as hypotension, is blood pressure that is so low that it causes symptoms or signs due to the low flow of blood through the arteries and veins. Some of the symptoms of low blood pressure include light-headedness, dizziness, or even fainting if not enough blood is getting to the brain. Diseases and medications can also cause low blood pressure. When the flow of blood is too low to deliver enough oxygen and nutrients to vital organs such as the brain, heart, and kidneys; the organs do not function normally and may be permanently damaged.
Diarrhea is a change is the frequency and looseness of bowel movements. Cramping, abdominal pain, and the sensation of rectal urgency are all symptoms of diarrhea. Absorbents and anti-motility medications are used to treat diarrhea.
Dehydration is the excessive loss of body water. There are a number of causes of dehydration including heat exposure, prolonged vigorous exercise, and some diseases of the gastrointestinal tract. The best way to treat dehydration is to prevent it from occurring.
Edema is the swelling of tissues as a result of excess water accumulations. Peripheral edema occurs in the feet and legs. There are two types of edema, non-pitting edema and pitting edema. Causes of pitting edema is caused by systemic diseases, most commonly involving the heart, liver, and kidneys. Local conditions that cause edema are thrombophlebitis and varicose veins. Edema is generally treated with medication.
Chronic cough is a cough that does not go away and is generally a symptom of another disorder such as asthma, allergic rhinitis, sinus infection, cigarette smoking, GERD, postnasal drip, bronchitis, pneumonia, medications, and less frequently tumors or other lung disease. Treatment of chronic cough is dependant upon the cause.
Nausea is an uneasiness of the stomach that often precedes vomiting. Nausea and vomiting are not diseases, but they are symptoms of many conditions. The causes of vomiting differ according to age, and treatment depends upon the cause of nausea and vomiting.
Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered to have a significant fever until the temperature is above 100.4 degrees F (38 degrees C.). Fever is part of the body's own disease-fighting arsenal: rising body temperatures apparently are capable of killing off many disease- producing organisms.
Epilepsy is a brain disorder in which the person has seizures. There are two kinds of seizures, focal and generalized. There are many causes of epilepsy. Treatment of epilepsy (seizures) depends upon the cause and type of seizures experienced.
Bioterrorism is a form of terrorism where there is the intentional release of biological agents such as viruses, germs, or bacteria. Diseases caused by bioterrorism agents include anthrax, botulism, plague, smallpox, tularemia, brucellosis, food poisoning, Q fever, ricin toxin poisoning, cholera, epidemic typhus, viral encephalitis, XDR TB, and MDR TB.
Fever refers to an elevation in body temperature. Technically, any body temperature above the normal oral measurement of 98.6 F (37 C) or the normal rectal temperature of 99 F (37.2 C) is considered to be elevated. However, these are averages, and
one's normal body temperature may actually be 1 F (0.6 C) or more above or below the average of 98.6 F. Body temperature can also vary up to 1 F (0.6 C) throughout the day.
Fever is not considered medically significant until body temperature is above 100.4 F (38 C). Anything above normal but below 100.4 F (38 C) is considered a low-grade fever. Fever serves as one of the body's natural defenses against bacteria and viruses which cannot live at a higher temperature. For that reason, low fevers should normally go untreated, unless accompanied by troubling symptoms.
Also, the body's defense mechanisms seem to work more efficiently at a higher temperature. Fever is just one part of an illness...