GWEN IFILL: For more on ricin and what we can understand about it, I'm joined by Julie Fischer. She studies biological and chemical weapons for the Henry L. Stimson Center, a nonprofit research center dedicated to issues of national and international security. Welcome, Ms. Fischer.
JULIE FISCHER: Thank you.
GWEN IFILL: We just heard Dr. -- Senator Frist tell us a little bit about what ricin is. Give us an understanding. This is not anthrax. What is ricin?
JULIE FISCHER: Ricin, unlike anthrax, is not a live agent. Anthrax is the spore of a bacteria that is alive and replicates and it's not contagious but is infectious. Ricin instead is a toxin. That means it's a chemical that's produced by a live being -- in this case a plant. It comes from the castor bean. So the amount of ricin that's there does not replicate anymore. The dose that was there yesterday is all the ricin that will be in the lungs or near the people who were exposed.
GWEN IFILL: The castor bean. Is that anything like castor oil, which our parents used to force on us when we were small?
JULIE FISCHER: It's in fact the source of castor oil.
GWEN IFILL: Castor oil itself obviously isn't lethal. But what is it about the way this castor bean is processed to make it into ricin that makes it lethal, poisonous?
JULIE FISCHER: Well, the ricin comes from the mashed up castor bean. In this case when castor beans are processed to make oil what's left over is a big mush of water and solids. The water, the aqueous part, contains ricin which is a very, very small molecule that has the ability to bind to cells in the body of an organism -- a human or an animal that is exposed. And it cripples them. It keeps them from making protein, and that causes those cells to die. So when enough cells die, it can cause damage and eventually enough damage could kill an infected person or an exposed person.
GWEN IFILL: We can't help when you talk about exposed persons but think back to what we went through during the anthrax scare. Now at that time, we were... we learned that anybody who was in the room, anybody who had been any place in breathing distance of this powder was in danger. That is not the same case apparently with ricin.
JULIE FISCHER: Well, the ricin actually has a much larger amount gram for gram that is required to be lethal than the anthrax spores. So not that there's a good thing about finding ricin in your office and it's clearly a threat that has to be taken seriously but it is a much less dangerous toxin.
GWEN IFILL: If you just touch it, it doesn't necessarily infect you.
JULIE FISCHER: No, and that's a very good contrast. Anthrax can infect the skin. In the case of ricin it actually doesn't pass through the skin very easily at all so it has to be pushed through the skin or breathed in or eaten by accident.
GWEN IFILL: As people start this investigation they're going to have to figure out who manufactured it and how it was manufactured. You described a process that doesn't sound like someone can do it so easily or is it easy?
JULIE FISCHER: It's actually relatively simple with some basic knowledge of chemistry. And the difficult thing about ricin is that it comes from a plant that's very common. In fact, castor bean oil is still made throughout the world and castor plants are used as ornamentals in the U.S., so unlike anthrax or other agents that should be in the hands of only a very few people, castor beans are fairly ubiquitous.
GWEN IFILL: If for some reason you are infected with ricin, how do you know?
JULIE FISCHER: Well, that's what makes this case actually a little bit easier to deal with. The fact that staff apparently saw the powder and took steps and notified authorities and the ricin was identified means that now it's a matter of watching for symptoms and trying to prevent damage should those symptoms occur, which they have not so far. If we were not aware of the powder, we would have to wait for symptoms to occur, people to present to their physicians and then try and backtrack, to go backwards and say we have this set of symptoms, what can we rule out? Identifying the powder first actually means that action can be taken quickly and the symptoms can be watched for carefully.
GWEN IFILL: It's been more than 24 hours now since we first heard the first or since the authorities were first notified about the first reports of this ricin sighting. If no one has turned up sick yet, is that fairly good news?
JULIE FISCHER: It bodes very well, yes. We don't actually have a lot of human cases of ricin inhalation to go from, but we do know from animal models that seem to be pretty accurate that signs would be likely to show up in the first four to eight to 24 hours after exposure. And the fact that no one has developed symptoms yet seems to bode pretty well for the outcome.
GWEN IFILL: And what are symptoms?
JULIE FISCHER: In the case of inhaled ricin, it would be problems breathing that would eventually progress probably if it were severe enough to a pneumonia which would make it very difficult to breathe and perhaps even be lethal.
GWEN IFILL: So you could have pneumonia and it could be brought on by the ricin not just garden variety pneumonia but there's no way to look at that and say these are the symptoms -- this is ricin poisoning?
JULIE FISCHER: Unfortunately there's no biological test for ricin, there's no blood test that you could take. And in the case of a covert attack, that's an attack that no one noticed, it would be a matter of ruling out other symptoms, other causes.
GWEN IFILL: We just heard Senator Frist say there is no antidote for it. Does that mean there is no cure?
JULIE FISCHER: That does mean there is no cure. The only treatment for ricin exposure, whether it's ingestion, that is eating or drinking, or inhalation is supportive care, helping the person who is exposed continue to breathe, keeping them hydrated with fluids, to try and get them past the worst part of the cell damage but there is no specific treatment.
GWEN IFILL: And how about the timing of the discovery, does that make a difference in this case?
JULIE FISCHER: Well, it does. In that because staff were sensitized -- and that was clearly a change from the attack with anthrax in 2001, which contained a letter that said this is anthrax. In this case staff were sensitized, noted the powder and took steps to notify authorities. And that clearly makes a difference. The medical professionals and emergency responders are looking for the effects and looking to protect the people who might have been exposed, rather than having to do detective work later and go backwards and find from people with symptoms whether or not an exposure had happened.
GWEN IFILL: You said a moment ago that there have not been that many documented cases of inhaled ricin poisoning among humans. Is there or are there any examples at all that investigators can draw from where they have seen this and where they know the way it plays itself out.
JULIE FISCHER: There are cases of ingested ricin and castor bean poisoning. And there are some inferences made from that to the animal models. We've looked at the animal models for ricin inhalation and said well the animal model for ingesting ricin looks a lot like what we know about from the human cases of ingested ricin. So let's assume the animal models of inhaled ricin also look a lot like human inhaled ricin would.
GWEN IFILL: We've heard the elected officials say today they're pretty certain this was terrorism. Are there examples that have been discovered that have been definitively proven that ricin poisoning or ingestion or inhalation was caused by terrorist activity?
JULIE FISCHER: There are a few small cases of intentional poisonings with ricin. They usually fall into the class of biocrimes, that is, a husband poisoning a wife for a case that you'd recognize as a simple crime, simple assault. But there has been a fear that ricin would be used as a biological weapon. There have been rumors it was used in the Iran-Iraq War in the early '80s. There have been stories that it was found in Afghanistan. And really the threat of ricin is that it's fairly easy to make from a source that is fairly common in nature, and it's also heat stable which makes a difference.
So although we don't have a lot of examples from history of its use, we know that the U.S. looked at it in the early days between World War I and World War II, and that it's possible to make into a weapon pretty cheaply and easily which makes it a serious threat to be considered.
GWEN IFILL: Julie Fischer, thank you very much.
JULIE FISCHER: Thank you.