The debris and combustion particles resulting from the destruction of the World Trade Center on September 11, 2001, have compromised lung function in surviving rescue workers. Medical researchers are studying members of the Fire Department of New York City (FDNY), who are tested regularly to see how much air they can exhale through a tube.

Number of exposed FDNY rescue workers: 11,766

Number who arrived before or during the collapse: 1,660

Two days later: 8,185

Three or more days later: 1,921

Median liters of air workers could exhale in one second during their last test before 9/11: 4.30

During their first test after 9/11: 3.93

Percent who had below-normal capacity before 9/11: 6.8

After 9/11: 15.3

Equivalent years of aging for lungs, one year after 9/11: 12

SOURCE: American Journal of Respiratory and Critical Care Medicine, August 2006