see related post … * Old Atlantic in response to Jim White
Jim White believes a 100-fold math error in the Amerithrax investigation improperly excluded suspects
- Substantial flaws still remain in the FBI’s explanation of the technical analysis on which they concluded that Bruce Ivins was the sole perpetrator of the anthrax attacks of 2001.
- I have found what appears to be an error in the analysis of how much material from RMR-1029 would have been required to produce the spores used in the attack letters.
- The result of this error is an overestimate, by a factor of 100, of how much material from RMR-1029 would have been needed to be used for each letter.
- Partially because of this overestimate, the FBI excluded as suspects other researchers who received samples from RMR-1029, claiming that they lacked the expertise both to produce such a large volume of material and to then prepare it as attack material.
- With the smaller estimate, most of the basis for excluding these individuals goes away, as simple procedures could be used to dry such a small amount of material.
- In doing his microscopic analysis, Ivins states clearly that he is working with a 100-fold (or, 1:100) dilution of material from the RMR-1029 flask. He also states that this dilution is at an approximate concentration of 3 X 108 spores per mL. From the information present on this page of the notebook, it is clear that the concentration of spores in RMR-1029 is approximately 3 X 1010 per mL.
- Ivins recovered 0.013 grams of powder from the envelope. He suspended this powder in water and then plated it out to determine the concentration of bacteria. He then computed a concentration of 2.1 X 1012 colony forming units per gram of powder. For spores that are perfectly viable, one spore corresponds to one colony forming unit. That means that 0.013 g of the powder contains 2.7 X 1010spores.
- A leading anthrax researcher who assisted the investigation expressed his expert opinion that 100 ml would have been required to create sufficient material to be used in one letter, for a total of 500 ml for the five letters. Nonetheless, we cannot say with certainty how much material was used in the letters.
- One hundred mL of RMR-1029 would be 3 X 1012 spores, 100-fold more than Ivins recovered from the envelope he analyzed. The only way the opinion of the anthrax researcher makes sense is if they mistakenly took Ivins’ 3 X 108 notation in the notebook as the concentration of spores in RMR-1029, when Ivins clearly states that is the concentration of the diluted material he analyzed.
- The lower concentration makes no sense as the spore concentration of RMR-1029 for several reasons.
- First, the description of how many large cultures were produced at Dugway and small cultures in Ivins’ lab to produce RMR-1029 would suggest that the purification process resulted in the loss of most of the spores produced, if the lower concentration of RMR-1029 is correct.
- In other words, the lower concentration for RMR-1029 would mean that the final concentration of RMR-1029 was approximately at or below the concentration of spores one achieves in a standard bacterial culture, even though over a hundred liters of culture were used to produce the one liter purified material in the RMR-1029 flask.
- An alternate explanation for the discrepancy would be if Ivins collected only one percent of the material in the envelope for his analysis, but that would mean that there was so much material in the envelope that it would appear overly stuffed.
- The bottom line, then, is that only one mL, not 100 mL of RMR-1029 would be required to produce the material in one envelope.
- I can see that statement being accurate for someone drying 100 mL of RMR-1029 five times (or 500 mL once), but most of the concerns about equipment and space go away if only 5 mL needs to be dried to produce the attack material without a need to grow and purify a large new culture using the RMR-1029 material as inoculum. Rather than a lyophilizer, simple vacuum filtration or air drying could be used on such a small amount of material, and the procedure could be carried out without attracting much attention.
It appears to me that the FBI has excluded hundreds of potential suspects on the basis of a math error.
Read more at …http://seminal.firedoglake.com/diary/30737