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Last Updated

28 Dec 2002

Source: Baltimore Sun, December 27, 2002.

Anthrax fighters await outcome

Brentwood: After months of preparation, the $100 million fumigation of the D.C. mail-sorting center is done. Will tests show the toxic spores have all been killed?

By Scott Shane

WASHINGTON - In the ancient battle of man against microbe, there has never been a scene quite like this:

Dozens of glistening silver tanker trucks loaded with liquid chemicals. Heated tents containing towering tanks where the chemicals are mixed to make disinfecting gas. Five miles of pipes to carry the gas into the sprawling Brentwood mail-processing center. Two hundred people working around the clock, guarding the perimeter, bending over test equipment, donning space suits to enter the hot zone.

"We had to build it from the ground up," says John H. Bridges III, an environmental engineer for the U.S. Postal Service and the "incident commander" in charge of the anthrax cleanup of the postal service's sprawling Brentwood mail-sorting center in Northeast Washington. "There's nothing else like it in the world."

Bridges was peacefully fishing near his Virginia home when the call came in October 2001 that he had just been appointed to take charge of the decontamination. He had no idea the job would last this long.

He and his colleagues are elated that the oft-delayed fumigation went smoothly Dec. 14, though tests still must make certain that all the anthrax spores were killed.

With its security fences and rows of tents, the cleanup operation looks like a cross between a military encampment and a refugee village. It is designed to vanquish an enemy that is at once vanishingly small and astonishingly tough.

If they could somehow be swept up and deposited in one place, all the anthrax spores scattered about the 14 million-cubic-foot interior of Brentwood would not come close to filling a single sugar packet.

Yet that same minuscule pile would contain millions upon millions of the spores that leaked from two letters sent to U.S. senators 14 months ago. And if they wafted into the air and were breathed in by unsuspecting postal workers, they would in theory be enough to wipe out the 1,600 employees scheduled to return to work this spring at Brentwood.

If the workers need any reminder of the tragedy that happened here, it is written on the fence: Brentwood has been renamed for the two postal workers who were fatally infected with anthrax, Joseph Curseen Jr. (case 16) and Thomas Morris Jr (case 15).

Tearing down the building without disinfecting might have spread dangerous spores through the neighborhood. So officials had to mount a meticulous decontamination, despite the huge cost.

Only days ago, the postal service estimated the cost of the cleanups at Brentwood and a smaller sorting facility in New Jersey as "in excess of $100 million."

By last week, when officials showed two dozen journalists around at Brentwood, the size of the "excess" was becoming clearer: Thomas G. Day, the postal service's vice president for engineering, says the likely bill will be $100 million for Brentwood alone, where the cleanup has already required more than 1 million man hours of labor. Cleaning the Trenton, N.J., plant will cost an additional $50 million, he says.

Such mind-boggling spending might be taken as a sort of unintended tribute to nature's ingenuity. Like other members of the Bacillus family of bacteria, Bacillus anthracis can take the form of growing cells or dormant spores, an adaptation that ensures its survival through extended droughts, searing summers or frigid winters.

After killing a cow or other mammal - its natural host - the living cells of the anthrax bacteria fall to the ground with their victim, revert to spore form and hide in the soil.

They appear to be able to survive in this state for centuries - until, for example, a rainstorm washes the spores to the surface where they are ingested by another cow.

Then, in the animal's warm, moist lungs or guts, they blossom into active cells and begin their deadly multiplication.

When human beings began to hunt for a weapon they could take from biology and use against one another, anthrax spores got a high ranking. Anthrax is not contagious, so it would not turn back and infect the people who used it. And the spores could survive even the blast of a bomb that would scatter its deadly payload over wide swaths of enemy territory.

In earlier times, bioweapons researchers in both the United States and the Soviet Union put anthrax near the top of their lists in their hunt for the ideal biowarfare agent. Evidently the still-unidentified anthrax mailer had the same idea.

"The spores are bound up in a round basketball shape, with a hard surface for chemicals to get through," says Curtis B. Thorne, a retired microbiologist who studied anthrax and other members of the Bacillus family at Fort Detrick and the University of Massachusetts for 46 years.

"You can expose them to heat or cold, light or UV [ultraviolet] and they're protected. And they can hide in very small places."

Thorne says he used to store spores of nontoxic Bacillus bacteria by putting the material in a pot of garden soil stored on a shelf - sometimes for decades. In fact, he says, he has some Bacillus subtilis in his home refrigerator in Amherst, Mass., that he collected more than 30 years ago.

Such durability makes for a difficult cleanup, as government scientists found when they scrambled for a method to use on the Hart Senate Office Building last year.

They considered formaldehyde gas, used in the early 1970s to cleanse the Fort Detrick buildings where anthrax was made, but formaldehyde is a suspected carcinogen.

They tried a germ-killing foam developed at Sandia National Laboratories in New Mexico, where its inventors claimed it would do no damage to offices and would dry to harmless dust.

Not so, says Dennis Carney, who oversaw the anthrax cleanup on Capitol Hill for the Environmental Protection Agency.

"It took paint and varnish right off the walls. It caked onto surfaces and literally had to be scraped off," he told a recent terrorism conference.

Finally the experts settled on chlorine dioxide, used widely to disinfect water and food.

Testing showed that to kill all spores required a gas concentration of 750 parts per million for 12 hours - if humidity and temperature were just right. Under political pressure to reopen the affected congressional offices, cleanup crews worked in two 12-hour shifts.

"We'd tell them [Senate officials] it was going to take three months, and they'd say, 'You have two weeks,'" Carney says.

The lessons learned at Hart were applied this month at Brentwood - only the space being fumigated was about 150 times larger.

Though they believe the spore kill went well, officials won't dismantle the miles of pipes until 4,000 samples are taken throughout the building and 8,000 test strips embedded with nontoxic anthrax-like spores are checked to make sure all are dead.

"You don't want to take down all the equipment and then find out you hadn't killed all the spores," says Day, the postal official. "You don't want to start all over again."