TUESDAY, Aug. 1, 2006 (HealthDay News) -- New York City's fire department rescue workers paid another heavy price for their heroic efforts in the dust-choked environment of Ground Zero: In the year after the terrorist attacks, the rescuers showed a reduction in lung function equivalent to 12 years of normal aging, according to new research.
"We were not surprised to find a significant reduction in lung function. But we were impressed by the size of the reduction," said the study's lead author, Dr. Gisela I. Banauch, of Montefiore Medical Center's pulmonary division in the Bronx, N.Y.
Analyzing tests given before and after 9/11 to 12,079 rescue workers, Banauch and her team found the steepest lung-capacity declines in the 1,660 workers who were either present when the North and South Towers collapsed or arrived later that morning. They also observed significant declines in the 8,185 workers who arrived two days after the collapse and in the 1,921 workers who arrived on or after the third day.
All the rescue workers were exposed to airborne pollutants from the 2001 tragedy, including pulverized building materials and combustion products.
Following the disaster, many, but not all of them, developed such symptoms as cough, wheezing and shortness of breath. "So far, the two most common respiratory diagnoses have been reactive airways dysfunction syndrome (RADS) and irritant-induced asthma," Banuach said. "For a significant number of workers, unfortunately, this has affected their ability to work."
Banauch said it was impossible to predict whether the dust-exposed workers will continue to experience an accelerated decline in lung function: "No one knows, because nothing like 9/11 has happened before," she said.
But she added that the massive exposure to irritating alkaline dust could possibly increase some workers' future risk of developing emphysema and lung cancer.
Banauch's study, published in the August issue of the American Journal of Respiratory and Critical Care Medicine, and co-authored by Dr. David Prezant, the Fire Department's deputy chief medical officer, noted that only 22 percent of the first responders frequently used respiratory protection, while only 32 percent of the intermediate responders and 50 percent of the late responders did the same.
"The lesson is that adequate respiratory protection should be available promptly for first responders, which sounds great but is obviously difficult to implement," Banauch said.
If the workers' respiratory injuries were caused by Ground Zero dust, it's "an additional element to the tragedy of September 11," Dr. John R. Balmes, of the University of California at San Francisco, wrote in an accompanying editorial in the journal. "This occupational morbidity could have been prevented with early and well-trained use of simple respiratory protective equipment such as N95 masks," he added. "Let us be better prepared for future disasters in many ways, including institution of plans to protect emergency responders from unnecessary occupational exposures to irritant dusts."
Since 9/11, evidence has mounted that workers were exposed to a toxic plume of gases and dust from cooked building materials and computers. In 2004, lawyers for more than 800 workers filed a billion-dollar class-action lawsuit against the owners of the World Trade Center that could eventually include hundreds of thousands of people who worked and lived near the site.
Since Banauch's research was restricted to rescue workers, she couldn't comment on whether or not other groups may also have experienced declines in lung function.
"Their average exposure to the dust was much less," she said. "We don't know if there needs to be a threshold dose below which any exposure was not harmful."
In response to the study, Lorna Thorpe, deputy commissioner of the Bureau of Epidemiology at the New York City Department of Health and Mental Hygiene, said, "There is evidence that some individuals who were exposed are experiencing serious respiratory problems, although data are not available on how many people are currently affected."
She added, "The scientific study being published by FDNY identifies substantial lung function decline in the year after 9/11 among firefighters, but their exposure was fairly unique, making it difficult to estimate the risk to residents. DOHMH will continue to monitor for long-term health issues that may be associated with WTC exposure."
In April, the department had found that 57 percent of the survivors it surveyed had reported new or worsening respiratory symptoms. About 62 percent of the survivors had been enveloped in the dust, smoke and debris spewed into the air as the towers collapsed, according to the department's report, which was published by the U.S. Centers for Disease Control and Prevention on April 8.
The survey, part of the city's ongoing World Trade Center Registry, involved only 8,500 of the 71,437 people who were affected by the attacks, and specifically excludes those involved in rescue and recovery efforts because they had a longer exposure time.
The New York City Department of Health has more information on the aftermath of the attacks.