Asbestos fibers in the air and rubble following the collapse of the World Trade Center is adding to fears in the aftermath of Tuesday�s terrorist attack. The true tragedy in the asbestos story, though, is the lives that might have been saved but for 1970s-era hysteria about asbestos.
Until 30 years ago, asbestos was added to flame-retardant sprays used to insulate steel building materials, particularly floor supports. The insulation was intended to delay the steel from melting in the case of fire by up to four hours.
In the case of the World Trade Center, emergency plans called for this four-hour window to be used to evacuate the building while helicopters sprayed to put out the fire and evacuated persons from the roof.
The use of asbestos ceased in the 1970s following reports of asbestos workers becoming ill from high exposures to asbestos fibers. The Mt. Sinai School of Medicine�s Irving Selikoff had reported that asbestos workers had higher rates of lung cancer and other diseases. Selikoff then played a key role in the campaign to halt the use of asbestos in construction.
In 1971, New York City banned the use of asbestos in spray fireproofing. At that time, asbestos insulating material had only been sprayed up to the 64th floor of the World Trade Center towers.
Other materials were substituted for asbestos. Though the substitute sprays passed Underwriters
Laboratories' tests, not everyone was convinced they would work as well.
One skeptic was the late-Herbert Levine who invented spray fireproofing with wet asbestos in the late-1940s. Levine�s invention involved a combination of asbestos with mineral wool and made commonplace the construction of large steel framed buildings.
Previously, buildings such as the Empire State Building had to have their steel framework insulated with concrete, a much more expensive insulator that was more difficult to use.
Levine's company, Asbestospray, was familiar with the World Trade Center construction, but failed to get the contract for spraying insulation in the World Trade Center. Levine frequently would say that "if a fire breaks out above the 64th floor, that building will fall down."
That appears to be what happened Tuesday, according to Richard Wilson, a risk expert and physics professor at Harvard University.
The two hijacked airliners crashed into floors 96 to 103 of One World Trade Center and floors 87 to 93 of
Two World Trade Center. Instead of the steel girders of the towers lasting up to four hours before melting, the steel frames of One World Trade Center lasted only one hour and forty minutes, while the steel frames of Two World Trade Center lasted just 56 minutes before collapsing.
Though many were able to escape during those times, thousands apparently were not, including the hundreds of firefighters and police killed when the buildings suddenly and prematurely collapsed.
Selikoff was certainly right to point out that some workers heavily exposed to certain types of asbestos fibers were at increased risk of disease. But Selikoff was wrong to press the panic button about any use of or exposure to asbestos. For example, no adverse health effect has ever been attributed to Levine�s technique of spraying wet asbestos, according to Harvard's Wilson.
We may now be paying a horrible price for junk science-fueled asbestos hysteria.
Steven Milloy is the publisher of JunkScience.com, an adjunct scholar at the Cato Institute and the author of the upcoming book Junk Science Judo: Self-defense Against Health Scares and Scams
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