Anthrax, Ivins and Silicon: What to Believe?

In his January 24, 2010 Op Ed article The Anthrax Attacks Remain Unsolved: The FBI disproved its main theory about how the spores were weaponized.(see excerpt below,) Edward Jay Epstein seems to effectively disprove the FBI's Summary of the Investigation of Dr. Bruce E. Ivins(PDF). But there are problems with this article.

For one, according to Sandia National Laboratories' news release of August 21, 2008 FBI unveils science of anthrax investigation: Sandia's work demonstrated anthrax letters contained non-weaponized form:

Using more sensitive transmission electron microscopy (TEM), Kotula and Michael’s research indicated that the silica in the spore samples was not added artificially, but was incorporated as a natural part of the spore formation process. The spores we examined, Kotula says, lacked that fuzzy outer coating that would indicate that they’d been weaponized.

. So the mere presence of silicon does not, according to Sandia, prove the Anthrax had been weaponized.

Another problem is that Epstein appears to be the only source for the claim that a 1.4% silicon content was reported by the FBI on on April 17, 2009. If that report is accurate, it certainly does raise more serious question about the FBI's case against Ivins.

As it stands we remain skeptical as to the merit of Epstein's claims. We need corroboration before we accept the claim of a 1.4% silicon content in the anthrax murder weapon. It also remains to be determined if that 1.4% value has any other reasonable explanation, if indeed it was present. IOW, could it have been added without coating the spores with a spray dryer?

From Epstein's article:

Yet the anthrax grown from it had silicon, according to the U.S. Armed Forces Institute of Pathology. This silicon explained why, when the letters to Sens. Leahy and Daschle were opened, the anthrax vaporized into an aerosol. If so, then somehow silicon was added to the anthrax. But Ivins, no matter how weird he may have been, had neither the set of skills nor the means to attach silicon to anthrax spores.

At a minimum, such a process would require highly specialized equipment that did not exist in Ivins's lab—or, for that matter, anywhere at the Fort Detrick facility. As Richard Spertzel, a former biodefense scientist who worked with Ivins, explained in a private briefing on Jan. 7, 2009, the lab didn't even deal with anthrax in powdered form, adding, "I don't think there's anyone there who would have the foggiest idea how to do it." So while Ivins's death provided a convenient fall guy, the silicon content still needed to be explained.

The FBI's answer was that the anthrax contained only traces of silicon, and those, it theorized, could have been accidently absorbed by the spores from the water and nutrient in which they were grown. No such nutrients were ever found in Ivins's lab, nor, for that matter, did anyone ever see Ivins attempt to produce any unauthorized anthrax (a process which would have involved him using scores of flasks.) But since no one knew what nutrients had been used to grow the attack anthrax, it was at least possible that they had traces of silicon in them that accidently contaminated the anthrax.

Natural contamination was an elegant theory that ran into problems after Congressman Jerry Nadler pressed FBI Director Robert Mueller in September 2008 to provide the House Judiciary Committee with a missing piece of data: the precise percentage of silicon contained in the anthrax used in the attacks.

The answer came seven months later on April 17, 2009. According to the FBI lab, 1.4% of the powder in the Leahy letter was silicon. "This is a shockingly high proportion," explained Stuart Jacobson, an expert in small particle chemistry. "It is a number one would expect from the deliberate weaponization of anthrax, but not from any conceivable accidental contamination."

Nevertheless, in an attempt to back up its theory, the FBI contracted scientists at the Lawrence Livermore National Labs in California to conduct experiments in which anthrax is accidently absorbed from a media heavily laced with silicon. When the results were revealed to the National Academy Of Science in September 2009, they effectively blew the FBI's theory out of the water.

The Livermore scientists had tried 56 times to replicate the high silicon content without any success. Even though they added increasingly high amounts of silicon to the media, they never even came close to the 1.4% in the attack anthrax. Most results were an order of magnitude lower, with some as low as .001%.