April 7, 2010 -- More than seven years after the terrorist attacks of Sept. 11, 2001, rescue workers still had trouble breathing after they inhaled from the cloud of dust that enveloped southern Manhattan, a new study concludes.
Doctors conducted a seven-year study of members of the New York City Fire Department who responded to the World Trade Center attacks between Sept. 11 and Sept. 24, 2001. The researchers were able to include 91 percent of the responding workers -- a total of 10,870 firefighters and 1,911 EMS workers.
By 2008, the rescuers who had significant declines in lung function a year after the attack had still not recovered, and the recorded drop in lung function was about 12 times the rate seen in normal aging. The research was published Wednesday in the New England Journal of Medicine.
"Exposed people want to have answers. Not just for themselves but for entire group," said Dr. David Prezant, senior author of the study and Chief Medical Officer of the Office of Medical Affairs, for the New York City Fire Department (FDNY). "I was at 9/11 and was exposed myself."
Prezant teamed up with doctors from New York University, Montefiore Medical Center and the Albert Einstein College of Medicine, among others, to track the workers exposed during the 9/11 attacks.
He said the partnership between the fire department, management and doctors in New York gave the study advantages over other research that has tried to assess health problems caused Sept. 11, attacks.
"Every worker in our study is a proven exposed worker," said Prezant.
Fire departments often use the same lung-function test from Prezant's study in physicals firefighters need to pass to stay on the job -- so unlike many other studies on the topic, these researchers had access to lung-function tests given to firefighters before 9/11 to compare to the tests after the attack.
Prezant also didn't have to recruit for study subjects from the general public, which might have skewed the results.
Major Study on Breathing Problems of 9/11 First Responders
"Our study is not influenced by selecting the most ill or least ill," said Prezant.
Overall, the study showed the proportion of firefighters with below-normal lung function went from 3 percent before the attacks to 18 percent after. Eight years later that number stabilized at 13 percent.
"We take these answers and immediately translate them into monitoring and treatment initiatives," said Prezant.
Doctors, politicians and lawyers have all looked to previous studies as a call, not only for better treatment, but better prevention too.
"The 9/11 terrorist attack resulted in an unprecedented environmental disaster. The urgency of the search and rescue efforts led to first responders not being diligent in protecting themselves from the dust cloud by wearing properly fitted respiratory protection, such as disposable NIOSH N95 masks," said Dr. James Sublett of the American College of Allergy, Asthma and Immunology.
"An emphasis on worker protection would have likely ameliorated the type of permanent lung damage demonstrated in this follow-up of the firemen and EMS workers," said Sublett, who is section Chief of Pediatric Allergy at the University of Louisville School of Medicine in Kentucky.
Lung specialists who reviewed the study said the damage to the rescue workers at Sept. 11 exceeds the usual smoke damage from fires.
"The decrease is much greater than that observed with historical smoke and dust exposure and appeared to permanently reduce lung function," said Dr. Mark Gladwin, chief of Pulmonary, Allergy and Critical Care Medicine at the University of Pittsburgh Medical Center. "There was an expectation that this would improve in the overall cohort, but this did not happen."
However, doctors pointed out that the study did have a silver lining. Although the firefighters and EMTs did not recover during the study period, they didn't get worse after the first year.
"While recovery does not appear to have occurred to any significant degree, the good news is that after the original damage to lung function the rate of lung function loss returned to the normal range," said Dr. Neil Schachter, the medical director at the Respiratory Care Department at Mount Sinai Hospital in New York City.
"The event had not caused an accelerating loss of lung function, as has been the case with some exposures," he said.