By Jia-Rui Chong
Los Angeles Times
Copyright 2006 Los Angeles Times
All Rights Reserved 

New York City firefighters who inhaled toxic dust after the collapse of the World Trade Center in 2001 suffered a sudden loss of lung capacity 12 times the normal rate that occurs each year as people age, according to a study of 12,000 firefighters released Tuesday.

Respiratory tests taken a year after the attacks showed the average firefighter exhaled about 23 cubic inches less air in one second than before Sept. 11 — a 9% decrease, the study found.

"It's pretty scary, actually," said Dr. John R. Balmes, a lung specialist at UC San Francisco and UC Berkeley who was not involved in the research. "I think it suggests the exposure was really pretty nasty."

Dr. Gisela Banauch, the lead author of the study and a pulmonary critical care specialist at Montefiore Medical Center in New York, said the decreased lung capacity did not put the firefighters at an immediate risk for death. But it does increase their risk for developing conditions that could narrow the airways, such as asthma and chronic obstructive pulmonary disease.

Dust from the World Trade Center buildings contained pulverized cement, glass fibers, asbestos, hydrocarbons and other hazardous chemicals.

Previous studies have examined the subsequent respiratory problems faced by emergency workers, survivors and nearby residents.

Banauch's study, published Tuesday in the American Journal of Respiratory and Critical Care Medicine, was able to measure the decline in lung capacity because the Fire Department of New York conducted regular testing in the five years before the attacks.

Banauch found that before Sept. 11, the typical firefighter exhaled an average of 262 cubic inches of air in a second. After Sept. 11, those who responded to the attacks exhaled an average of 240 cubic inches.

Healthy, nonsmoking adults normally lose about 2 cubic inches of lung capacity each year.

Dr. Neil W. Schluger, a pulmonary specialist at Columbia University Medical Center in New York who was not involved in the research, said the decline was about six times that experienced by smokers.

The researchers also found that the percentage of firefighters with below-average lung capacity more than doubled after the attacks from 6.8% to 15.3%.

Masks did not seem to protect the lungs much, the researchers said. About 22% of those who arrived at the scene early and 50% of those who arrived later used masks frequently during the rescue effort, but their lung capacity results varied little from each other.

Banauch doesn't know whether the lost lung capacity is permanent. She said a smaller study of 150 rescue workers that she was involved with suggested that many of the problems persisted for years.

Dr. Robin Herbert, an internal and occupational medicine specialist at Mount Sinai School of Medicine in New York who was not involved in the study, said the findings underscored the need to continue monitoring of emergency workers exposed to World Trade Center dust.

"The most important take-home message for the responder community is the importance of getting medical care, diagnosis, treatment and care early to prevent long-term health problems," she said.

Lungs have a lot of extra capacity that can function like a "spare tire," Schluger said of the firefighters' prognosis. If the firefighters "are otherwise healthy for the rest of their lives, they might do pretty well."