With confirmation that a letter mailed to U.S. President Barack Obama contained ricin, there has been renewed focus on the deadly poison that is easy to make and has no antidote.
The naturally occurring substance, which is found in castor beans, was also found on an envelope addressed to Republican Mississippi Sen. Roger Wicker.
It鈥檚 been years since ricin was in the news, having last been found in the sorting area of a U.S. Senate mail room back in 2004. However, the security concerns following the Boston Marathon bombings have prompted the questions: What is ricin, and how worried should the general public be?
What is ricin?
Ricin can be found in the waste left behind when castor beans are processed into castor oil, and can be made into a powder, a mist or a pellet, or can be dissolved in water.
Ricin is categorized as a 鈥淐lass B鈥� threat, the CDC鈥檚 second-highest threat level. Also in that category are anthrax, botulism, plague and smallpox.
How likely is exposure?
The U.S. Centers for Disease Control and Prevention (CDC) says 鈥渋t would take a deliberate act to make ricin and use it to poison people. Unintentional exposure to ricin is highly unlikely, except through the ingestion of castor beans.鈥�
Ricin can be spread via the air, food and water, but ricin poisoning itself is not contagious. The U.S. Department of Homeland Security says ricin is most dangerous when inhaled. However, planning such an attack is not as easy as manuals may suggest.
"Making ricin into something that can be released from an envelope into the air, be the right size to be inhaled and stick in the lungs is a lot to get right, especially if you are not a bioterrorism specialist and know how to do that,鈥� Dr. Patricia Quinlisk, medical director of the Iowa Public Health Department and a bioterrorism expert, told The Associated Press. 鈥淚t's not something you can do in your garage."
One of the most famous cases of ricin poisoning was in 1978, when Bulgarian writer Georgi Markov was attacked in London by a man wielding an umbrella designed to inject a ricin pellet.
Symptoms
When ricin gets into the body, it prevents cells from creating the proteins they need to survive. Symptoms can appear as early as four to eight hours and up to 24 hours after exposure.
If inhaled, ricin can cause difficulty breathing, fever, cough, nausea, sweating and fluid build-up in the lungs. Low blood pressure and respiratory failure can also occur, which can lead to death.
If ingested, ricin can cause vomiting or diarrhea, and lead to severe dehydration, low blood pressure and then liver and kidney failure.
Death can occur sometime between 36 and 72 hours.
Treatment
There is no antidote so the most effective treatment is 鈥渁voiding ricin exposure in the first place,鈥� the CDC says.
If exposure does occur, the key is to get the poison out of or off the body as soon as possible. Contaminated clothing should be removed with rubber gloves and put into a plastic bag along with other exposed items. Local health authorities can advise on disposal.
Exposed skin should be washed with soap and water. If vision becomes blurred, rinse eyes for 15 minutes and throw away contact lenses.
If ricin has been ingested, treatment may include intravenous fluids or a stomach pump.
