Workers at the site reported cases of a signature "World Trade Center cough" and many said they suffered from such symptoms as itchy eyes and runny noses, even after the site cleanup ended in 2006.
The news is not all bad, however. Medication and other treatment could help those who were exposed, Moline said.
Dr. Norman Edelman, chief medical officer of the American Lung Association, said that researchers still need to figure out what comes next for those exposed to the pollution.
"We don't know what it means for future health so we must, as the authors suggest, continue to follow them," he said.
Research released in September by the New York City health department looked at a wide range of people exposed to the World Trade Center disaster, including nearby residents and commuters. Authors of that study estimated that more than 400,000 people were exposed to the disaster. An estimated 35,000 to 70,000 of them developed post-traumatic stress disorder, and 3,800 to 12,600 people developed asthma as a result.
Find out more about the health of people exposed to the 9/11 attack at the World Trade Center Health Registry.
SOURCES: Jacqueline Moline, M.D., director, World Trade Center Medical Monitoring and Treatment Program Clinical Center, New York City; and Norman Edelman, M.D., chief medical officer, American Lung Association, New York City; February 2009 Chest
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