Interesting detective work by Derek Lowe on Corante (Thanks, Peter for directing me to this site, written at a level I can understand)
Wednesday, December 3, 2003
Anthrax - Again
The latest issue of Science magazine (Nov. 28, 302, 1492, no free link for non-subscribers) has disturbing article on the notorious anthrax powder from the fall of 2001. Journalist Gary Matsumoto has been covering the story for some time, and his piece here (a long one by Science's standards) seems driven by his despair at the FBI's handling of the case.
Now, I wrote a series about chemical weapons back before the Iraq war, on my Lagniappe site, and I thought about expanding it to biological weapons at the time. But it's a difficult and depressing subject - the chemical weapons were bad enough, but at least they're antiquated. Biowarfare is (unfortunately and damnably) state of the art. But Matsumoto's eyebrow-raising article is enough to make me return to the topic. Besides, most of what he's talking about is chemistry - and some of it is actually pharmaceutical chemistry.
The big question has always been: were the anthrax spores made by civilian technology? Could they have been? Or did they have the signs of classified-level expertise? There have been conflicting reports, to say the least, and the FBI (these days, anyway) is not talking about the subject at all. Some of the obvious tests couldn't answer the question. For example, initial investigations showed that the anthrax was the Ames strain, which didn't narrow things down very much. (Well, it did show that the spores's producers had picked a virulent strain and hadn't cultured something out of the nearest barnyard.)
So Matsumoto concentrates on the processing of the spores: their particle size, and their possible coatings and treatments to make them disperse better. This is where the homebrew/high-tech distinction should be clear, and this is just where the available information has the most contradictions. Initially, reports were that the spore samples had very small, very uniform particle sizes, and may well have had additives to them to keep them from aggregating. Alan Zelicoff, of Sandia, was quotedat the time saying that whoever made the Senate anthrax had "the keys to the kingdom." (I remember reading that, and having a sudden, terrible vision of just what kingdom that was.) But you can now find leaks and reports that dispute both of these contentions, though. The difference is especially marked in statements the FBI has made in the last few months, which make the spores sound much less well-processed than their earlier reports. As Matsumoto puts it:
The reversal was so extreme that the former chief biological weapons inspector for the United Nations Special Commission, Richard Spertzel, found it hard to accept. "No silica, big particles, manual milling," he says: "That's what they're saying now, and that radically contradicts everything we were told during the first year of this investigation."
One of these contradictions is around the question of whether the anthrax spores were electrostatically charged. If they all were given a static charge, they would tend to repel each other, staying as separate particles and dispersing more readily. Some now claim the spores had no charge, others say that they did, but it was an artifact of the postal sorting machinery, and others say that it was a deliberate and sophisticated bit of processing.
Another controversy is whether the spore samples contained silica. That's in there to make the spores bumpy at a microscopic level, which keeps their glycoprotein-rich coats from contacting each other closely. Unrestrained contact causes severe clumping, because there are so many hydrogen bonds and van der Waals forces involved that. Different bioweapons programs over the years have used different sorts of silica (making it a potentially important marker).
Even more exotic, and distinctive, are potential coadditives to make the silica particles bind to the spores, such as some sort of polysiloxane (known, rather inaccurately, as "polymerized glass.") I say exotic from a pharmaceutical perspective, since they're generally not additives that are used (or needed) for drug preparations. But polysiloxanes, as compounds, are quite well-known; there's all kinds of literature on them. Just go to the paints and coatings industry, and you'll find all you'd want to know. What's obscure, though, is their use in weaponizing bacterial spores. . .you'd have to have done that research on your own, or be in contact with those who did.
So, who knows about these techniques, then? Well, there are two places that do a lot of research into finely milled inhaled powders: secret bioweapons labs, and pharmaceutical companies. I don't have many web links to offer for the former, but drug companies are glad to talk about their efforts, and to try to sell you their services (as are some ). The second half of this PDF presentation will give you an overview of what's going on in the pharmaceutical dry-powder inhalation field. Nektar, formerly Inhale Therapeutics, has deals with Aventis and Pfizer for several projects, most famously their long-running attempt to make an inhaled insulin powder for diabetics. Another company pursuing the same goal is Aradigm. And Dura was taking a crack at inhalation technology, before being bought by Elan three years ago.
Has the FBI investigated these research efforts? I'd be surprised (and disappointed) if they hadn't. But, needless to say, drug companies don't spend a heck of a lot of time working with anthrax spores. Not much of a market for an anthrax inhaler, you know. But there's one intersection of the pharmaceutical world and the classified-defense-contractor world that comes to mind: Battelle. Not only do they have sophisticated particle technology, as that link will demonstrate, but (according to Matsumoto) another Battelle division has, in the past, actually done research-scale anthrax production for Defense Dept. and US intelligence. The FBI says that it has interviewed Battelle personnel, but has no further comment.
It's important to note, as Matsumoto stresses, that there is no evidence linking Battelle to the 2001 anthrax. (Nor is there any to link another logical site on the bioweapons side of things, the Army's Dugway Proving Ground in Utah.) But if it's true that the anthrax showed signs of sophisticated technology, places like this (or their equivalents in foreign countries) are the ones to investigate. Matsumoto hammers on the point that the FBI's basement-anthrax theories have come to a dead end. They and the Army appear to have been unable to reverse-engineer the Senate anthrax using home-style technology.
We still don't know where the 2001 anthrax came from. The story has just become more confused as time goes on. But what worried me then, and worries me now, is that if you're going to go to the trouble of making this stuff, you might as well make a good-sized batch. Remember the note, in the letter that was sent to Daschle's office? "We have this anthrax," it said. I thought at the time that it meant "We have this anthrax," meaning, the good stuff. I remember that I was surprised when the anthrax attacks stopped. I wonder if they really have.
posted at 10:36 pm |
