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FBI Ignored, Hid Data Potentially Excluding Bruce Ivins as Anthrax Killer

9:16 am in Uncategorized by Jim White

FBI photos of the material in the letter sent to Senator Pat Leahy (left) and to the New York Post (right), from the report.

A report from McClatchy provides important new evidence and analysis in the FBI’s Amerithrax investigation of the 2001 anthrax attacks. The report shows that the FBI ignored as potentially erroneous a measurement of silicon in one anthrax sample and then hid this information from Congressman Jerrold Nadler (D-NY). Even more importantly, the high silicon measurements in at least two samples also were coupled with high tin measurements, opening up the possibility that silicon was added to the attack material in a form that is not mentioned in any of the FBI documents. Significantly, it is virtually impossible that Bruce Ivins, whom the FBI has concluded acted on his own to carry out the attacks, would have been able to perform the necessary chemical manipulations involved in this treatment of the spores.  Ivins likely also would not have had access to the necessary laboratory equipment to perform this treatment.

The presence of silicon and how it may have gotten into the anthrax material has been a point of great controversy throughout the entire investigation. This question is important because the chemical nature of the silicon and the level at which it is present is presumed to be an indicator of whether the anthrax spores have been “weaponized” to make them suspend more readily in air so that they are more effective in getting into the small passageways of the lungs of the intended targets of the attack. Early in the investigation, Brian Ross published “leaked” information that the spores had been weaponized through addition of bentonite and that Iraq had a weaponization program that used bentonite. This report turned out to be false, as no evidence for bentonite has been found. A more sophisticated type of weaponizing would rely on mixing the spores with nanoparticles of silica (silica is the common name for the compound silicon dioxide) to make them disperse more easily.

The FBI carried out a special form electron microscopy that could identify the location of the silicon in the spores from the attack material. They found that the silicon was in a structure called the the spore coat, which is inside the most outer covering of the spore called the exosporium. If silica nanoparticles had been used to disperse the spores, these would have been found on the outside of the exosporuim (see this diary for a discussion of this point and quotes from the scientific literature) because they are too large to penetrate it.  No silicon signature was seen on the outside edge of the exosporium.  What is significant about the type of silicon treatment suggested in the McClatchy piece is that both high silicon and high tin measurements were found in several samples and that there is an alternative silicon treatment that would involve a tin-catalyzed polymerization of silicon-containing precursor molecules. McClatchy interviewed scientists who work with this process and they confirmed that the ratio of silicon to tin found by the FBI is in the range one would expect if such a polymerization process had been used. Read the rest of this entry →

Would the NAS Report Have Led to Reasonable Doubt in an Ivins Trial?

12:02 pm in Uncategorized by Jim White

FBI photos of the material in the letter sent to Senator Pat Leahy (left) and to the New York Post (right), from the report.

It seems very likely to me that had Bruce Ivins not died, the analysis carried out by a panel from the National Academy of Sciences in assessing the scientific evidence tying Ivins to the 2001 anthrax attacks would have led to reasonable doubt on whether Ivins carried out the attacks. For this post, let us concentrate only on the NAS response to FBI claims on the spores used in the attack, especially with regard to how the spores were prepared.

What we do know from the report is that the spores used in the attacks did not come directly from Bruce Ivins’ RMR-1029 flask, but had to undergo a culturing step if RMR-1029 was even the source. Also, the spore material in different individual mailings differed in purity and particle size.  Silicon was present in the spores, but was not added as a step to “weaponize” the spores.  Instead, the silicon was incorporated into the coating of the spores themselves.   Finally, the NAS panel did not feel there was sufficient evidence to support the FBI claim that a highly skilled person had prepared the material.

Overall, the importance of the primary conclusion of the NAS report cannot be overstated (p. 4 of the report as marked, all references will use internal page numbers, not pdf numbers from my pre-publication copy):

It is not possible to reach a definitive conclusion about the origins of the B. anthracis in the mailings based on the available scientific evidence alone.

A good defense attorney probably would need no more than that conclusion to establish reasonable doubt in a trial.  But the details on how the panel reached that conclusion are important.

In this post, I discussed whether Ivins could have produced all of the material used in the attacks with the equipment he had available and without drawing attention to himself.  That post opened with a discussion of how many spores were known to have been present in the attacks.  I looked at what was in the FBI’s report, filled in some gaps with my experience in microbiology and came to the conclusion that somewhere between four and seventy liters of liquid culture could have produced the attack material.  The NAS report comes to a similar conclusion on page 62:

Thus, cultivation in the range of 2.8 to 53 liters of liquid medium would have been required to produce the spores required for the letters (see Table 4.2).

Interestingly, the panel also calculated that it would have required between 463 and 1250 agar plates if the attack material had been produced on solid medium.  It seems highly unlikely Ivins could have cultured this many extra Petri dishes without someone in the lab taking note and reporting it to the FBI once the investigation began.

The photo above shows how dramatically different the highly purified material in the letter sent to Senator Patrick Leahy’s office was when compared to the material mailed to the New York Post.

There had been much speculation early on in the press that the material sent to Senator Leahy’s office had been “weaponized” by the addition of materials including silicates to make tiny particles remain suspended in the air so that they could be inhaled.  The report documents that although silicon is found in the spores used in the attacks, the silicon is localized in the spore coats.  This point is driven home very clearly in this photo, where the silicon can be seen “lighting up” within the outer lining of the spores:

Many experiments were carried out in an attempt to match the silicon content, the particle size distribution and the degree to which the final material would remain suspended in air.  I will rely here on the entire summary the panel provided on the issue of silicon in the spores (page 71):

The substantial effort devoted to the characterization of silicon in Bacillus spore coats resulted in new fundamental insight into microbial processes and the development of new or enhanced analytical measurement technology. (Table 4.4 presents a summary of the analytical results.) Elemental analysis of the letter samples showed that 1) the silicon content was high, 2) most of the silicon was incorporated in the spore coat, 3) the majority of spores in the samples contained silicon in the coat, and 4) no silicon was detected in the form of a dispersant in the exosporium.

The bulk silicon content in the Leahy letter could be completely explained by the amount of silicon incorporated in the spores during growth. (Not enough material was available to make this comparison for the Daschle letter.) In contrast, the New York Post letter had significant bulk silicon content, far exceeding that contained in the spores.

No studies have considered the effect of the chemical form of silicon (e.g., silicate impurity versus polydimethylsiloxane antifoam agent) on uptake. The inability of laboratory experiments to reproduce the silicon characteristics of the letter samples is not surprising given the complexity of the uptake mechanism.

A few spores analyzed from RMR-1030 contained silicon in the coat, but none of the spores analyzed from RMR-1029 contained silicon in the coat. Therefore, the letter samples could not have been taken directly from the flasks—a separate growth preparation would have been required.

The material in the Daschle and Leahy letters was reported to have “a high level of purity” and to have electrostatic properties that caused it to disperse readily upon opening of the letters. These properties should be regarded as qualitative observations since they were not based on quantitative physical measurements. The committee received testimony (Martin, 2010) stating that some Dugway preparations, particularly those utilizing lyophilization but no dispersant, gave products with similar appearance and electrostatic dispersibility as the letter samples, suggesting that these properties were not necessarily connected to an intentional effort to increase dispersibility through addition of a dispersant. Exogenous silicon and bentonite, which enhance the dispersibility of spore preparations, were not found in the Leahy and Daschle letters.

Note that this analysis provides the strongest evidence to date that the spores used in the attacks did not come directly from the RMR-1029 flask, because the spores in the flask do not have the silicon content as those in the attack material. Note also that growth in the presence of polydimethylsiloxane-containing antifoam agents is seen as one route that needs to be investigated for how silicon can be incorporated at elevated concentration in the spores, just as I suggested in this post.

It is also worth noting that highly purified spores produced at Dugway did have the aerosolizing quality of the attack material. No additional treatments besides purification were needed for these spores to disperse in air, so I suspect that is one of the primary reasons that the NAS panel could not support the FBI claim that someone with a very high level of expertise must have prepared the material used in the attacks.

Rush Holt Blasts FBI for Withholding Documents from Outside Review of Scientific Work in Anthrax Investigation

5:07 am in Uncategorized by Jim White

The infamous RMR-1029 flask genetically linked to the anthrax attack material.

[Ed. note: Link to Rep. Holt's statement and letter have been added below.]

Both the New York Times and McClatchy report that Congressman Rush Holt (D-NJ) has written a letter to the FBI, blasting them for requesting a delay in the release of the final report from the National Academy of Sciences panel that has been reviewing the scientific analyses used in the FBI’s Amerithrax Investigation of the 2001 Anthrax mailings. It appears that in requesting the National Academies to delay release of its final report, the FBI has released an additional 500 pages of documents to the panel, but only after having seen the draft final report from the panel.

Here is McClatchy discussing Holt’s letter (which I don’t see posted on Holt’s website; I will call and request a copy Link to PDF letter here):

Holt, a scientist and the chairman of the House Select Intelligence Oversight Panel, said the academy recently shared with the bureau its draft report on the “Amerithrax” investigation, a narrow scientific review that the FBI requested in 2008 in an effort to quell controversy over its findings that a disgruntled government scientist was behind the attacks.

“This week I was informed by the NAS that the FBI would be releasing an additional 500 pages of previously undisclosed investigative material from the Amerithrax investigation to the NAS,” he wrote. Holt said he understands that the “document dump . . . is intended to contest and challenge the independent NAS panel’s draft findings.”

“If these new documents were relevant to the NAS’ review, why were they previously undisclosed and withheld?” Holt wrote. He requested a meeting with the FBI director.

In the Times, Scott Shane reports that the National Academy has agreed to extend its study:

E. William Colglazier, the academy’s executive officer, said the F.B.I.’s request was a surprise and came after the bureau saw the panel’s peer-reviewed final report, which was scheduled for release in November. He said that the committee’s 15 members, top scientists who serve as volunteers, were “exhausted,” but that the panel had agreed to extend the study and consider revising the report in return for an additional fee, probably about $50,000, beyond the $879,550 the F.B.I. has already paid for the study.

Dr. Colglazier declined to say if the report was critical of the F.B.I.’s work but said it was “very direct.” The report sticks to science and does not offer an opinion on whether Dr. Ivins carried out the anthrax attacks, he said.

The McClatchy article also quotes Holt as saying of the FBI that it “consistently botched and bungled this case from the beginning.” In addition to the early focus on Steven Hatfill as the primary suspect, followed by a settlement of more than $4 million paid to Hatfill after he was cleared of involvement, several aspects of the FBI case do not appear to withstand scientific scrutiny.

In this diary, I pointed out that the amount of highly purified anthrax material that was used in the mailings would have been very difficult, if not impossible for Bruce Ivins, whom the FBI stated was solely responsible for the attacks, to have produced at his government laboratory without arousing the suspicion of his coworkers. The small shake flasks that Ivins would have used produce very little material, so he would have had to grow anthrax in a very large number (over 35 or so) of the cultures he normally grew.

On the other hand, a single production of spores from a fermenter of at least 70 liters would have produced enough anthrax spore material to account for what was used in the attacks. Further, in this diary, I point out that the abnormal silicon content of the spores used in the attack can be accounted for by the presence of an agent called “antifoam”, that is added to microbial cultures when they are grown in large fermenters, again suggesting that the attack material was produced in a fermenter to which Ivins did not have access.

I had been monitoring the website for the National Academies investigation regularly since the project’s slated termination in late October, looking for their final report. It appears now that we all will have to wait a bit longer before we see that report. My only hope is that Rush Holt is making sure that David Margolis is not allowed anywhere near the report before it is made final.

(h/t to @jaraparilla for alerting me to the Times article and to Retired Military Patriot for finding the McClatchy article)