Toxic dust and fumes around New York's collapsed World Trade Center in 2001 have aged the lungs of rescue workers by 12 years, researchers said Tuesday.

Gisela Banauch, an author of the study published in the American Journal of Respiratory and Critical Care Medicine, wrote that before the attacks of Sept. 11, 2001, an ongoing survey of some 12,000 emergency workers' scores showed an annual drop of about 31 milliliters of lung volume a year, associated with normal aging.

However, in the year after the attacks, rescuers lost an average of 372 milliliters of volume in respiratory capacity, a decline doctors would expect to see after 12 years of aging, Banauch wrote.

Banauch, a physician at New York's Montefiore Medical Center, said it wasn't known if lung function will continue to deteriorate or whether rescuers' lungs will heal some of the damage.

The swirling air after the towers collapsed contained more than 400 chemicals, USA Today reported.

Copyright 2006 by United Press International