WASHINGTON — An acclaimed government scientist who assisted the federal investigation of the 2001 anthrax mailings said Tuesday that he erred seven years ago when he told top Bush administration officials that material he examined probably had been altered to make it more deadly.
The scientist, Peter B. Jahrling, had observed anthrax spores with the aid of an electron microscope at the government's biological warfare research facility at Ft. Detrick, Md.
On Oct. 24, 2001, Jahrling was summoned to the White House after reporting to his superiors what he believed to be signs that silicon had been added to anthrax recovered from a letter addressed to then-Senate Majority Leader Tom Daschle (D-S.D.).
The presence of silicon was viewed with alarm because the material, if artificially added to the anthrax, would make it more buoyant in air and more capable of penetrating deeply into the lungs.
"I believe I made an honest mistake," Jahrling said in response to questions e-mailed to him for this article, adding that he had been "overly impressed" by what he thought he saw under the microscope.
"I should never have ventured into this area," said Jahrling, who is a virologist, referring to his analysis of the anthrax, which is a bacterium. Jahrling's initial analysis -- and his briefing of officials at the White House -- was first detailed in a 2002 book by bestselling author Richard Preston.
Although Jahrling was careful in 2001 not to implicate Iraq or any other regime in the mailings, others used his analysis to allege that the silicon perhaps linked the letters to Iraqi President Saddam Hussein.
Inhaled anthrax can kill at a rate of 80% to 90% unless patients are treated quickly with an antibiotic.
Jahrling's comments Tuesday came soon after a congressional hearing at which FBI Director Robert S. Mueller III announced that he was arranging for an outside review of scientific findings that helped the bureau conclude that another scientist at Ft. Detrick, Bruce E. Ivins, perpetrated the deadly mailings. The review is to be overseen by the National Academy of Sciences, Mueller said.
FBI scientists and outside experts hired by the bureau to analyze the anthrax recovered from the mailings announced Aug. 18 that although they had found silicon, it occurred within the spores naturally and was not added.
In challenging those experts, one journalist reminded them that Jahrling, among other scientists, had concluded otherwise.
