by Katherine Stapp
dust hangs in the air and small fires continue to smoulder in the rubble of the World Trade Center, now known as "ground zero," as thousands of commuters return to their jobs in lower Manhattan.
While crews continue the laborious process of sifting through more than a million tons of debris, with hopes of pulling out survivors all but extinguished, officials are trying to protect them and other workers from exposure to the lingering stew of fumes, ash, dust and smoke.
Large swathes of the financial district have been open since last Monday, although National Guard troops and police continue to staff barricades to cordon off the blocks immediately surrounding the Trade Center plaza.
There were initial fears that a toxic cloud of asbestos fibers had been released when the buildings collapsed, but air and dust sampling by the Environmental Protection Agency (EPA) and the Labor Department's Occupational Safety and Health Administration since Sep. 13 has revealed either no asbestos in the air, or relatively low levels -- from 2.1 to 3.3 percent, compared to a one-percent threshold.
A fleet of huge vacuum trucks was deployed last weekend to suck up much of the dust. Still, some office workers returning to the financial district yesterday wore paper face masks -- although these are ineffective in blocking ultra-fine asbestos fibers.
Doctors stress that permanent health damage from asbestos fibers, once used as an insulation material but now banned, almost always results from long-term exposure.
More difficult to assess are the numerous other chemical compounds released during the initial jet fuel inferno and the subsequent explosive collapse. Benzene, formaldehyde, polychlorinated hydrocarbons, and countless other carcinogens were, and still are, present at the site, as are poisonous gases containing carbon monoxide and cyanide.
Aside from the known hazards, the fusing of glass, concrete, electronics parts, plastics and countless other materials in the towers created new and potentially deadly compounds.
"We have a unique situation that can produce some unique combinations of chemicals," said Cynthia Wilson, executive director of the Chemical Injury Information Network, a non-profit advocacy group.
"Chlorine, for example, hates to be on its own," said Wilson. "It will bind to anything that passes to create unknown compounds, with usually devastating effects."
Jet fuel alone releases some 100,000 chemical byproducts when it combusts, she said, and it is unclear what effect many of these have on human health.
Experts said the long-term consequences for the thousands of people who were massively exposed when the buildings came down, and for workers now at the site, are impossible to gauge at this point.
"If someone is ill now, they'll probably be okay. If they're still ill in three months, they have something to be concerned about," Wilson said.
Problems from exposure to chemicals and toxic dust can range from temporary respiratory irritation to permanent neurological damage and cancers like leukemia.
the worst of the toxic smoke at the site dissipates, "most of the hazards now would be dermal and skin contact," said Peter Bellin, a California State University professor of environmental and occupational health.
The New York Committee for Occupational Safety and Health (NYCOSH), a coalition of 200 local unions and individual health and safety experts, issued guidelines to thousands of its members on how to protect themselves during the clean-up, which could take a year or more.
"It virtually goes without saying that the smoke has toxic ingredients," said Jonathan Bennett, the coalition's public affairs director. "You have toxic gases versus particulate matter (like soot and asbestos). Particulate respirators don't protect people from carbon monoxide, for example."
Recommendations in the eight-page NYCOSH fact sheet include proper use of non-disposable respirators with frequent filter changes, goggles, and skin protection. Workers are urged to change clothes before going home.
The Nuclear Regulatory Commission said it tested the Trade Center area and found "nothing worrisome" in terms of radiation levels.
The federal Department of Health and Human Services has set up two emergency treatment centers for workers at the site. The Atlanta-based Centers for Disease Control and Prevention also has a team in place to monitor worker safety needs.
The debris is being moved by truck from lower Manhattan through the Brooklyn-Battery Tunnel and across the Verazzano Narrows Bridge to the Fresh Kills landfill in Staten Island, which was reopened after the disaster. The EPA has ordered that the rubble be hosed down and covered with plastic sheeting before leaving the area, to minimize spillage and contamination risks during transport.
The overflowing Fresh Kills site, which had been closed, is not considered a suitable permanent store for the massive volume of debris being trucked in from the Trade Center. No decision has been announced on where the rubble will eventually end up, although it seems likely to be dispersed to landfills around the country.
EPA Administrator Christine Todd Whitman said toxic components are being separated from the rest of the waste at the Trade Center site and sent to locations elsewhere in Manhattan, although she did not specify the locations.
Meanwhile, the landfill is being treated like a giant crime lab, with Federal Bureau of Investigation forensics experts sorting through the rubble for clues and evidence.
September 24, 2001 (http://www.monitor.net/monitor) All Rights Reserved. Contact email@example.com for permission to use in any format.
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