WASHINGTON - A sample taken from a plastic evidence bag containing a still-unopened letter to Sen. Patrick Leahy contains at least 23,000 anthrax spores, enough for more than two lethal doses, a federal law enforcement official said yesterday.
The official, speaking on condition of anonymity, said there were three times more anthrax spores in the single sample taken from the plastic bag than in any of the other 600 bags of mail examined by the FBI before it found the Leahy letter.
Meanwhile, traces of the bacteria have been found in the office mailrooms of Sens. Edward Kennedy, D-Mass., and Christopher Dodd, D-Conn., said one Congressional official speaking on condition of anonymity.
Officials suspect the anthrax got there through contact with anthrax-bearing letters mailed to Leahy or Senate Majority Leader Tom Daschle, D-S.D. So far, anthrax traces have been found in 13 senators' offices besides Daschle's, whose office is the only one known to have actually opened an anthrax letter.
Word of the anthrax spores in the Leahy letter, first reported by The New York Times, followed the FBI's announcement that it is convinced the Leahy letter was sent by the same person who mailed an anthrax-tainted letter to Daschle. Both were postmarked Oct. 9 in Trenton, N.J.
Investigators are looking into the possibility the Leahy letter was misrouted initially, resulting in anthrax contamination at a State Department mail facility that sickened one worker.
In Atlanta, meanwhile, Tom Skinner, spokesman for the Centers for Disease Control and Prevention, said Monday that the agency planned to test a substance found in a letter that the Chilean government said was tainted with anthrax. The government of Chile said the letter was from an American company in Switzerland to a company in downtown Santiago. It declined to identify either company.
The Leahy letter found Friday will be mined for information based on a plan by the FBI, the Army and outside science experts who want to maximize the evidentiary value of the document, the FBI said Monday.
"FBI and Centers for Disease Control investigators hope that this careful, scientifically agreed upon approach will yield clues that will help identify the source," the bureau said in a statement.
At the Pentagon, officials began taking new precautions against anthrax-tainted mail by requiring that all mail be opened, visually inspected, X-rayed and tested for biological or chemical materials. Once checked, mail will be held for up to three days to await test results before delivery inside the building.
The Leahy letter was found by the FBI and hazardous materials personnel from the Environmental Protection Agency in one of 280 barrels of unopened mail sent to Capitol Hill and held since the discovery last month of the letter to Daschle.
The outside of the Leahy letter appears virtually identical to the Daschle letter and bears the same fictitious "Greendale School" return address, all-capital block letters and other characteristics.
The matching characteristics of the Leahy and Daschle letters "have combined to convince investigators" that both were "sent by the same person," the FBI said.
U.S. postal inspector Dan Mihalko said the Leahy letter contains a handwritten ZIP code of 20510 that may have been read as 20520 by optical character reader machines at the postal service.
"That's the exact change needed to forward something to the State Department," Mihalko said.
"It raises an interesting possibility that the letter to Leahy could have been misdirected through the State Department mail system initially, which might explain how that system got contaminated," he added.
A 59-year-old employee of the State Department's mail facility in Sterling, Va., was hospitalized Oct. 25 after lab tests confirmed he had inhalation anthrax. He recovered.
On Capitol Hill, the Dirksen and Russell Senate Office buildings reopened Monday after being swept for anthrax contamination after the discovery of the Leahy letter. The Hart Senate Office Building remained closed.
The Kennedy and Dodd offices are both in the Russell building. People who work in those offices will not need medical treatment because the amounts of anthrax were so low, an official said.
In a statement, Kennedy said he would close his office early for the Thanksgiving holiday as a precaution while the mailroom is decontaminated, and expects to reopen Monday. He said the Capitol physician has concluded that the anthrax there "poses no public safety or health risk."
EPA officials have said it will take three to four weeks to decontaminate the offices of 10 senators in the Hart building in which traces of anthrax have been found, a Senate aide speaking on condition of anonymity said. Those cleanups have not yet started.
Two other offices where bacteria were found - Daschle's and the next-door suite of Sen. Russell Feingold, D-Wis. - will be sealed and cleaned with chlorine dioxide gas.
Officials originally hoped Hart, which houses half the Senate's 100 members, would be cleaned and reopened by Nov. 21. With the new cleanup timetable, authorities have set no new target date, but many aides believe the building may not reopen until next year.
The FBI said all congressional mail set aside after discovery of the Daschle letter had been inspected, and the Leahy letter was the only suspicious piece.
Four people have died from anthrax: two Washington postal workers, a hospital employee in New York City and a newspaper photo editor in Florida.
