Screening procedures put in place after 9-11 detected letters testing positive for ricin mailed to the President and Sen. Roger Wicker of Mississippi.
According to the Associated Press, both letters were postmarked from Memphis, Tenn. and contained the same message: “To see a wrong and not expose it, is to become a silent partner to its continuance. I am KC and I approve this message.”
A day after the tainted letters were discovered, the FBI arrested Paul Kevin Curtis at his apartment in Corinth, Tenn. for the mailings.
The letters were intercepted at off-site mail-screening facilities that were established following the anthrax attacks in 2001, when letters containing that poison were mailed to two senators. Officials said they were encouraged that the protective measures in place were effective in detecting the poison. “The bottom line is, the process we have in place worked,” Sen. Claire McCaskill of Missouri said to CNN.
That process includes sensors with chemical detection devices to routinely check for a variety of agents like ricin or anthrax.
“I think the important thing to note is that there are a variety of different systems in place throughout the country that address the air in metropolitan areas and specifically addresses items like mail that are constantly sniffing either the air or these items to detect possible things like ricin,” says Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. “In this case, the system worked quite well, it picked it up before it ever was delivered.” Osterholm served as a Special Advisor to former Secretary of Health and Human Services Tommy G. Thompson on issues related to bioterrorism and public health preparedness from 2001 through early 2005.
(MORE: Letter With Ricin Sent to Senator: How Dangerous Is the Toxin?)
The initial screen involves imaging incoming mail, which can detect ricin from unopened parcels. When a potential biohazard is detected, facility members contact law enforcement officials who generally notify the FBI and state health officials. The U.S. Centers for Disease Control and Prevention (CDC) is also informed, and the contaminated letter or package is sent to a special laboratory for additional testing. The lab could be one that is part of a state public health system, or a lab that belongs to the Laboratory Response Network — a national network organized by the CDC that has a wide range of testing capabilities and is prepared to respond to threats involving biological and chemical weapons. Officials at the FBI said those tests are currently underway on the letters.
According to the CDC, those confirming tests include one that uses an antibody that binds to ricin and a DNA-based analysis that confirms that the sample contains specific genetic sequences unique to the toxin.
How at-risk are mail handlers and laboratory technicians during this process? Ricin does not absorb easily through the skin, and it’s impact is largely dependent on how an individual is exposed and to how much of the poison. Inhaling powder or pellets is the most dangerous form of exposure, since it the toxin can immediately reach delicate lung tissue and impair breathing, but so far the FBI has not reported that anyone was sickened from inhalation during handling.
“Ricin is a fairly potent toxin. In terms of the amount needed to make someone sick, it is a very tiny amount. But you do need to effectively get it into the body somehow. Just putting a little bit into the envelope seems like a pretty inefficient way to deliver the toxin,” says Dr. Greg Moran, a professor of clinical medicine at the UCLA School of Medicine department of emergency medicine and division of infectious diseases. “The way most people handle a letter and open it, they are not going to get a really significant amount into their lungs or their intestinal track. It seems unlikely this would be an effective way to get people sick, but it will hit the news and scare people in that way. Which is probably their goal.”
(MORE: FBI Says Letter to President Obama Tests Positive for Ricin)
It is also a fairly simple poison to make. “It doesn’t require a high level of sophistication or credible technology or fancy equipment,” says Dr. Ken Spaeth, the director of occupational and environmental medicine center in the department of population health at the North Shore University Hospital in Manhasset, New York. “It can be done pretty simply. That’s partly why it is considered a viable threat and is among the listed biological agents of concern. It’s a naturally occurring product from the castor bean, so it is available to anyone who has this plant and with relatively little training or skill it can be extracted and used. Frankly, anyone with internet access can find instructions on how to do that.”
This potentially makes it an easier threat to carry out than using an agent like anthrax, which was the focus of a letter-based terror campaign in 2001, says Spaeth. Despite the fact that anthrax is a bacteria that can replicate and spread easily through the air, it’s less easy to acquire. “In my mind, I think ricin is among the most dangerous compounds out there,” Spaeth says, “given that access to it is not as limited as some of the other biological weapons. This is something that occurs in nature and therefore there is wider access to it and because it is relatively easy to extract the toxin from it, ricin is quite concerning particularly because its toxicity is so great. It doesn’t take very much to be lethal.”
There is no treatment for ricin poisoning, and the CDC advises removing contaminated clothing and washing exposed areas as the most effective ways of lowering risk of more severe toxicity symptoms.
For now, the mail facility where the letters arrived has been shut down temporarily, and Senate Majority Leader Mitch McConnell of Kentucky said to CNN that he was reassured that “the proactive measures we put in place do, in fact, work.”