Why anthrax? From the start of the modern era of bioweaponry, Bacillus anthracis has held a unique appeal for those seeking to militarize microbes. Although Japan's Air Force scattered millions of bubonic-plague-carrying fleas and other pathogens from planes over 11 Chinese cities beginning in 1940, triggering mini-epidemics that killed some 700 Chinese and sent thousands more to the hospital, plague and most other pathogens have serious drawbacks as weapons. Plague requires cooperative animals (the fleas must bite the victim), and viruses such as variola, which causes smallpox, multiply only in living cells, making the production of arsenal-size quantities a stiff challenge. But bacteria such as anthrax, when fed little more than yeast extract, proliferate happily in a plain old lab dish. Plus--and this is anthrax's greatest appeal--the bacteria readily form hardy, dormant spores that keep for years, obviating the need to make fresh batches. When the United States began its offensive biological-weapons (BW) program in 1942 at Camp (now Fort) Detrick in Frederick, Md., Britain and the Soviet Union were already working to add anthrax to their arsenals.
The global history of weaponized anthrax suggests that investigators will have no dearth of suspects as they pursue those responsible for killing one person and infecting at least eight others with mailborne spores since Sept. 11. So far, the spores mailed to American Media Inc. in Florida, to NBC in New York and to Sen. Tom Daschle's office in Washington seem to be the same strain of anthrax (that is, of approximately the same genetic composition), suggesting a single source. The powder sent to Daschle's office appears to have been prepared by someone who knew what he was doing. In contrast to the AMI spores, most of which fell harmlessly onto a computer keyboard (only the man who held a suspect letter to his face and breathed in the spores died), the powder sent to the Senate was fine enough to become airborne. That allowed 22 staffers and two Capitol Police officers to breathe it in. With anthrax, hang time matters. Half a dozen countries have managed to produce anthrax in an easily inhaled aerosol (the respiratory route to infection is the most deadly). To do that requires knowledge and equipment. Knowledge exists in the minds of the thousands of scientists who worked in the American, British, Soviet, Iraqi and other government anthrax programs. After the fall of the Soviet Union, many of its researchers were lured overseas. "There were people I knew very well who were in Iraq or Iran and other Muslim countries," says former Soviet BW scientist Sergei Popov. And equipment is only a supply house away.
The Soviet BW program, launched before World War II and ramped up during the cold war, showed the ease of producing anthrax in bulk. By the 1980s the Soviets could produce thousands of tons of weaponized anthrax annually, says Ken Alibek, former deputy head of the Soviet BW agency Biopreparat. "People think it's difficult, but we were able to manufacture it in 20- and 50-ton reactors," he says. Biopreparat also created antibiotic-resistant anthrax, by using standard recombinant DNA techniques to splice in a gene for resistance from a common microbe like E. coli. Because antibiotics kill the anthrax recently sent through the mail, investigators doubt that Russian stores were the source.
At Camp Detrick, America's anthrax warriors grasped the need to aerosolize the germ. They produced some 5,000 anthrax bombs, but even the most effective released only 3 percent of its spores; the rest got blown into the ground or vaporized by the heat of detonation. So the Army changed tactics. From September 1950 to February 1951 its researchers tested dispersal methods by spraying stand-ins for anthrax (bacteria like the supposedly harmless Bacillus globigii) over San Francisco. In June 1966 they released an anthrax substitute into the New York City subway. Aerial dispersal of aerosolized anthrax spores, it seems, would work lethally well.
President Richard Nixon halted America's offensive BW program in 1969. Russia says it halted work in the 1980s--when Iraq was just getting started. Saddam Hussein put his BW program under the aegis of Iraq's intelligence service and sited it in Salman Pak on the Tigris River. A terrorist training camp shared the site, says Raymond Zilinskas, a former United Nations weapons inspector now at the Monterey Institute of International Studies. The program was led by Iraqi Rehab Taha, who received her Ph.D. in biology at England's University of East Anglia in the 1980s and who, upon joining the BW program, outlined a five-year plan for "industrial production of germ agents." She wasted no time. In 1985 she received fermenters and other equipment, as well as two anthrax cultures from France's Pasteur Institute. In April 1986 the Ministry of Trade, acting as a front for her program, bought seven strains of anthrax from the American Type Culture Collection, a biological supplier: the seven included three isolated at Detrick, the so-called Vollum strain and a Lederle Labs strain. The next year the ministry began buying tons of bacterial growth media, including yeast extract, and anthrax production began in the desert 35 miles southwest of Baghdad. Taha was good at her work. By 1989 her team had succeeded in agglomerating the spores into fine particles perfect for aerosolizing, says former U.N. weapons inspector Richard Spertzel. To reduce particle size to the respirable ideal, Iraq used "sequential filters" in devices about the size of coffins--a setup almost identical to that used at Detrick in the 1950s. Iraq field-tested anthrax not only in aerial bombs but also in sprayers attached to helicopters, fighter aircraft and possibly unmanned drones.
Some of Iraq's BW experts, according to a 1998 congressional task force, dispersed to Libya, Sudan and Algeria after the gulf war. Both Algeria and Syria reportedly still conduct bioweapons research. And despite the 1972 treaty banning biological weapons, say American intelligence sources, so do other nations. China is suspected of maintaining an offensive-bioweapons program. Egypt had developed biological-warfare agents by 1972. Iran "may have small quantities of usable [BW] agent now," the Pentagon concluded earlier this year. The Soviets apparently "seeded" their cold-war allies with BW know-how. "We had a nice collaboration with North Korea," says Popov, who defected to Britain in 1992. "They traveled to our facilities several times." Pyongyang's BW program had begun by the 1960s, and in 1970 placed an order with a Japanese firm for large quantities of anthrax, cholera and plague bacteria. Today, concludes a 2001 U.S. Defense Department report, North Korea "may have [those three] biological weapons available for use."
Investigators know less about anthrax in nongovernment hands. In September 1999 Ahmad Ibrahim al-Naggar, a member of Egyptian Islamic Jihad, reportedly confessed to Egyptian security that the terrorist group had obtained anthrax from an East Asian country for $3,695 (plus shipping). Egyptian Islamic Jihad is an ally of Osama bin Laden's Qaeda network. And last year Mohamed Atta, suspected mastermind of the Sept. 11 atrocities, may have met in Prague with an Iraqi intelligence official. In the United States, hundreds of labs store anthrax in order to study vaccines, treatments and even genetic susceptibility to the disease. The labs are required to register with the government, but it is not clear whether all do. "Microbiologists are kind of like squirrels," says Dr. Craig Smith, an infectious-disease specialist at Phoebe Putnam Memorial Hospital in Georgia, who advised the military during Desert Storm. "They keep bacterial strains all over the place, in university and even private collections."
With so many BW programs around the world, thousands of scientists have learned how to turn anthrax into a weapon. To put knowledge into practice, a rogue researcher would need equipment. And that's not hard to acquire. In 1999 agents in the U.S. Defense Department's Project Bacchus fanned out across the country to buy new and used filters, pipes, glassware, nutrients, a fermenter (to grow colonies of anthrax) and a milling machine (to grind down clumps of spores to the most infectious size). By summer 2000 their $1.6 million had equipped a mini BW plant; it made two pounds of simulated anthrax ("simulated" because they used a harmless bacterium like B. globigii to stand in for the deadly one). "So many of these machines are dual-use," says Smith. "The same small, sealed milling unit used for producing pharmaceuticals can be used to weaponize anthrax. Fermenters can produce antibiotics as well as bioweapons. Culture media can grow bacteria for vaccines as well as weapons."
Investigators have not ruled out either domestic or foreign sources for the anthrax used in the recent attacks. Clues from the physical and biological properties of the samples sent through the mail, they hope, may point to a source and hence a suspect. Biologically, the spores sent to NBC, American Media and Senator Daschle are indistinguishable. None, a lead investigator tells NEWSWEEK, match the seven samples Iraq bought from ATCC. Instead, they resemble a strain that labs across the world use in research, and one that Iraq tried unsuccessfully to buy from Britain in the 1980s. Physically, the spores sent to Daschle are what Spertzel describes as "in very small particles and readily dispersible into the air," apparently allowing the 22 Senate staffers to inhale them. (It didn't help that the woman who opened the anthrax letter panicked, tossing it into a trash can and releasing spores into the air.) Keeping the clumps small requires manipulating the electrostatic charge (the same kind that causes static electricity) between spores. For that, the sort of equipment found in pharmaceutical or biology labs would be useful.
Investigators are not ruling out a connection with Al Qaeda, but the letters to Daschle and NBC appear homegrown. Daschle's, which bore the return address of a fourth-grade class, said, "We have this anthrax. You die now... Death to America. Death to Israel. Allah is great." NBC's read, "This is next. Take penicillin now," plus the last three phrases of Daschle's letter. A powder-containing letter sent to AMI (but not recovered) contained a little star of David, recall staffers. So, too, NEWSWEEK has learned, did the anthrax letter to Daschle.