... an article in Aerosol Science and Technology published in March 2008 has acquired considerable significance in light of the announcement by the F.B.I. last week that it would close its nine-year investigation of the 2001 anthrax attacks in the United States.
Aerosol Science and Technology reported on an attempt by a group of scientists at the Dugway Proving Ground in Utah to reproduce the dry, powderized substance that was found in one of the anthrax-laden envelopes mailed by the perpetrator of the attacks, in which 5 people were killed, 17 were sickened and the country, reeling from the Sept. 11 attacks of just a few weeks before, was sent into high alert.
The title of the paper, “Development of an Aerosol System for Uniformly Depositing Bacillus Anthrax Spore Particles on Surfaces,” demonstrated that to create anthrax in a dry aerosol form of the sort that can be dispersed through the air is a long and difficult process involving a lot of highly specialized machinery.
The original culture has to be incubated; spore pellets are then collected with a centrifuge; those spores are dried “by a proprietary azeotropic method,” before an “amorphous silica-based flow enhancer” is added to turn the otherwise sticky anthrax spores into an aerosol, after which the material has to be passed through a series of ever finer mesh screens that are activated by a pneumatic vibrator.
The point, as one scientist specializing in fine particle chemistry told me, blows a large hole through the 92-page summary of the investigation released last week by the F.B.I. and the Justice Department, the main conclusion of which is that Bruce E. Ivins, a scientist at the U.S. Army Medical Research Institute of Infectious Diseases at Fort Detrick, in Maryland, was the anthrax mailer.
“Note that the proprietary azeotropic drying technique and the pneumatic mill are both superspecialized pieces of equipment, neither of which is at Detrick,” the specialist in fine particles, Stuart Jacobsen, said in an e-mail message.
But the F.B.I.’s entire case against Mr. Ivins is that he was able to manufacture the anthrax used in the attacks at his Fort Detrick lab, working late at night on the days before the actual anthrax mailings so nobody would see what he was doing.
At first, reading the F.B.I. report is to be swept up in the conclusion that the perpetrator of the deadly anthrax attacks was indeed Mr. Ivins.
Several hundred other scientists over the years have had access to the material in that particular flask, but according to the F.B.I., all of them except for Mr. Ivins were exonerated. Mr. Ivins committed suicide two years ago just as prosecutors were moving to indict him — an act that seems, under the circumstances, to be highly incriminating.
And yet, when you look a bit closer at the F.B.I.’s report, doubts persist, and they lend a good deal of credibility to the arguments of those, including some of Mr. Ivins’s former colleagues, that the F.B.I.’s case, as Representative Rush D. Holt of New Jersey put it last week, is “barely circumstantial.”
The report, for example, makes much of the fact that Mr. Ivins worked late at night in his lab in the days prior to the mailing of the anthrax, something he had not usually done, and that he had no alibi for what the F.B.I. report calls the “mailing windows,” the stretches of time when the perpetrator of the attacks deposited the anthrax-laden envelopes into a post office box in Princeton, New Jersey, a three-hour drive from Mr. Ivins’s lab.
That information seems very damning at first glance, but according to Jeffrey Adamovicz, Mr. Ivins’s supervisor at Usamriid, as the Fort Detrick facility is known, the F.B.I.’s claim that Mr. Ivins rarely worked at night — and only did so in the days before the anthrax was mailed — is simply untrue.
“Although I cannot directly dispute the hours the F.B.I. has shown for access to B3/4” — Mr. Ivins’s anthrax lab — “Bruce was well known for working late and early,” Mr. Adamovicz said in an e-mail message this week. “He may not have been in B3/4 but instead in his office or the BSL-2 labs. I think a broader examination of his access to all areas of the lab would confirm this.”
Beyond that, Mr. Adamovicz said, “the F.B.I. seems to be locked into the concept that the spores had to be prepared in the week before each of the mailings.”
“I’m unclear as to why they believe this other than that period matches to hours that Bruce was in suite B3/4 at night,” he said. “These spore preps could have been made anytime between 1997 and 2001, in my estimation.”
But most important is the failure of the F.B.I. to demonstrate that the anthrax used in the attack was actually produced in Mr. Ivins’s lab at Fort Detrick, or even that it could have been produced there. In a recent opinion article in The Wall Street Journal that poked holes in the F.B.I.’s case, an investigative reporter, Edward Jay Epstein, cites a letter written by the F.B.I. director, Robert S. Mueller III, in which Mr. Mueller says that the mailed anthrax contained 1.4 percent silicon — without which the anthrax would be a clumpy, sticky mess, according to Dr. Jacobsen, the fine-particles specialist.
Mr. Adamovicz said in his e-mail message: “This is very strong evidence that a process more sophisticated than Bruce Ivins or Usamriid possessed was used in making the spore preparations. I and others have calculated that it would take several weeks to months to grow the 5-10 grams of spores required for the letters using common lab protocols and laboratory capabilities present in Usamriid for growing spores.” He added, “The F.B.I. to date has provided no information on how this could be done.”
The point is not that Mr. Ivins wasn’t the anthrax mailer. Perhaps he was. But some of the F.B.I.’s arguments seem like conclusions in search of arguments, while other aspects of the report — notably its failure to deal with the silicon question — are conspicuously incomplete.