TESTS DIFFER ON ANTHRAX CONTAMINATION AT POND



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Last Updated

30 May 2003

Source: Washington Post, May 30, 2003

Tests Differ on Anthrax Contamination at Pond

By Marilyn W. Thompson and Allan Lengel, Washington Post Staff Writers

FBI investigators who have tested a plastic box and other equipment recovered this winter from a pond near Frederick have received two conflicting assessments of whether the items are contaminated with anthrax bacteria, the deadly microbes used in the 2001 attacks that killed five people and sickened 13 others, according to government sources.

One test result was positive for anthrax bacteria, but a second laboratory reported finding no trace of the deadly spores, according to investigators close to the case. The conflicting results have touched off debate within the FBI in recent weeks about whether the bureau should move to drain the one-acre pond in a further search for possible evidence.

Some FBI investigators believe the device, described as a plastic or plexiglass box with holes cut into it that would allow someone wearing gloves to manipulate material inside, could have allowed the attacker to fill envelopes with anthrax bacteria using water as a means of protection.

An enduring mystery of the case is how the killer prepared the envelopes for mailing without inhaling anthrax spores and becoming ill himself. Authorities are also puzzled about why they have found no anthrax contamination in the many locations they have searched.

The FBI developed plans in early April to drain the pond in the hope of finding anthrax contamination or additional equipment the attacker might have used to prepare the envelopes, which were mailed to news media and government offices.

Tests are continuing. It is not unusual to get conflicting lab results, or false positive results, in tests for anthrax spores. Experts who work with scientific equipment point out that testing in this case would be especially difficult because the material could have been submerged for some time.

But the contradictory findings in two separate laboratory tests of material pulled from the pond led to the internal debate over the wisdom of draining the spring-fed pond in Frederick Municipal Forest, according to sources close to the investigation. Other equipment pulled from the pond includes glass vials and gloves wrapped in plastic.

Some agents fear that draining the pond, estimated to cost $250,000, could prove useless and embarrassing. Others argue that promising initial findings in the pond -- including the discovery of the box -- left the FBI little choice but to explore the water more thoroughly, the sources said.

Maryland state and local officials say they are awaiting word from the FBI about the operation, which had been expected to begin by June 1. The FBI sent divers into the pond's icy waters in late December and early January, then kept the secluded area under surveillance while officials consulted with contractors about draining the pond once a thick blanket of ice had melted.

The FBI first focused on the pond, part of an area known as the Frederick watershed, after a business acquaintance of Steven Hatfill -- described as a "person of interest" in the investigation by Attorney General John D. Ashcroft -- revealed that Hatfill once described how he might dispose of equipment contaminated with deadly bacteria, according to the sources.

Hatfill, who lived a few miles from the pond in an apartment complex outside Fort Detrick, worked as a researcher at the U.S. Army Medical Research Institute for Infectious Diseases in the late 1990s.

Hatfill has repeatedly said he had nothing to do with the anthrax attacks, and contends that he is being harassed by the FBI, which has had him under 24-hour surveillance for months. He is unemployed and lives with his girlfriend near Georgetown.

Pat Clawson, a spokesman for Hatfill, said yesterday that "the bottom line is the FBI can keep draining all the ponds in the world, but they're never going to find any evidence that Steve Hatfill was the anthrax killer because he was not the anthrax killer. They can drain the Pacific Ocean if they want; Steve Hatfill is not the anthrax killer, period."

The business acquaintance's tip offered a clue to how the bioterrorism crimes could have been carried out, and has led to the FBI's novel theory that the criminal could have waded into the water to manipulate anthrax spores or remove stuffed envelopes from a protective container. Water would help suppress the movement of finely ground spores. The anthrax spores used in the letters addressed to Sens. Thomas A. Daschle (D-S.D.) and Patrick J. Leahy (D-Vt.) were highly refined and considered dangerous to handle even with a mask and other laboratory protections.

While water provides some degree of protection from anthrax spores, according to experts, some question whether it would be possible to work with refined powder while standing in water. They suggest that it would be more likely for a criminal to simply fill the envelopes on land and dispose of the equipment in a pond to avoid detection.

The 19-month-old anthrax case -- code named Amerithrax -- has stretched the FBI's scientific capabilities and generated criticism of the investigation's pace and the agency's tactics in trying to draw information from possible witnesses.

Following the tip, a team of FBI agents last December converged on the 7,000-acre municipal forest, blocking off roads in the area, which is about 10 miles from the Frederick city limits and Fort Detrick. The diving team cut through thick ice and plunged into several small man-made ponds. The FBI has refused to reveal what equipment the divers found.

In early January, about eight members of the elite FBI diving team attended Florida State University to take special classes in gathering forensic evidence underwater, part of a new law enforcement training program funded by the Defense Threat Reduction Agency. Instructor Thomas Kelley said the divers mentioned nothing about the Frederick operation but took classes that included special instructions in diving at sites that could be contaminated with biological or chemical agents.

In early April, the FBI alerted officials at the Maryland Department of the Environment that the agency wanted to drain the pond. Department spokesman Jim Pettit said the agency concluded that the FBI would not have to go through a formal review process.

He said the agency sent environmental investigators into the area to make sure that no plant or wildlife would be harmed, particularly the endangered Eastern Diamondback rattlesnake, Allegheny woodrat and several species of orchids that grow in the area.

State officials also consulted with Frederick city officials about the safety of the city's water supply. "We checked with the city, which is the owner of the drinking water system, and they had no concerns," Pettit said. "Given the volume of water and the distance from the intake, there's no chance of contamination."

Pettit said the agency offered the FBI advice "on how to carry out the drainage of the pond in an environmentally sensitive manner," such as removing the water slowly to avoid a surge in nearby creeks. He said the FBI plans to hire a contractor to drain the pond, and state officials will supervise the project.

In recent weeks, Frederick Mayor Jennifer P. Dougherty (D) has tried to dispel concern that anthrax bacteria might have contaminated the city's drinking water supply. At several news conferences, the mayor said that while the ponds in question do ultimately feed into the city's water supply, they are far enough away from the city's prime water sources, and the water is treated thoroughly enough that the spores would pose no danger.

Marc Stachowski, the city's water chief, said the city routinely tests for 10 to 12 toxic compounds in the water supply. Although the city does not look for anthrax spores, Stachowski and other city officials said they were confident that the combination of filtration and treatment with chlorine gas would kill any spores that made it into the city's water supply.

Staff writers Lori Montgomery and David Snyder contributed to this report.