Nearly 70% of the workers and volunteers who spent time at Ground Zero and other sites following the 9/11 attack on the World Trade Center reported a new or worsened respiratory symptom that developed during or after their time working at the sites.

That finding and others were released Sept. 5 by the Mount Sinai Medical Center. They are based on the Center’s WTC Worker and Volunteer Medical Screening Program, the largest multi-center clinical program providing medical screening examinations of WTC disaster responders.

The data of the study come from medical examinations performed between July 2002 and April 2004 on 9,500 WTC responders. These responders were a diverse group including members of the building trades, law enforcement officers, firefighters, utilities and telecommunications workers, transit workers, and others. All received a comprehensive examination that included pulmonary function tests, chest x-ray, blood tests and urinalysis. Overall, the monitoring program examined close to 12,000 responders during the 21-month period covered by the study, 9,500 of whom agreed to allow their results to be used in the report.

The study found that a high proportion of those examined became sick as a result of their WTC work. It found also that illnesses have persisted in the years since 9/11 in a high proportion of the workers. In one area alone — pulmonary function tests — the study found WTC responders had abnormalities at a rate twice that expected in the comparable U.S. population and that these abnormalities persisted for many months and, in some cases, years after exposure.

“Many who worked at Ground Zero in the early days after the attacks have sustained serious and lasting health problems as a direct result of their exposure to the environment there,” said Dennis Charney, dean for academic and scientific affairs for the Mount Sinai School of Medicine, which has been running a number of medical and mental health programs serving responders since July 2002. “This study scientifically confirms high rates of respiratory problems in a large number of responders.”

The study focuses on respiratory health consequences, one of the earliest areas of concern to emerge. Researchers found that many responders were symptomatic, with high rates of pulmonary function abnormalities as long as two-and-a-half years after the disaster. The findings are particularly striking, in that the workers who served at the WTC tended to be vigorous, healthy people who held jobs in strenuous professions before 9/11.

Specific findings included:

• Almost 70% of WTC responders had a new or worsened respiratory symptom that developed during or after their time working at the WTC.
• Among the responders who were asymptomatic before 9/11, 61% developed respiratory symptoms while working at the WTC.
• Close to 60% of responders still had a new or worsened respiratory symptom at the time of their examination.
• One-third of responders had abnormal pulmonary function tests, much higher than expected.
• Severe respiratory conditions including pneumonia were significantly more common in the six months after 9/11 than in the six months prior.

Rates of respiratory symptoms and pulmonary function abnormalities were positively correlated with how early the responders arrived at the WTC site. Those who arrived first at the site suffered the heaviest exposures and had the most frequent respiratory problems. Researchers say this represents a major public health issue, as most of the responders screened by Mount Sinai were heavily exposed, with 70% having arrived at the site between Sept. 11 and 13.

The report concludes that continuing long-term medical monitoring of responders will be needed to track the persistence of the abnormalities discovered in the study and to identify late effects, including possible malignancies. Mount Sinai continues to screen responders and has tested an additional 4,000 since April 2004.

“An estimated 40,000 rescue and recovery workers were exposed to caustic dust and airborne toxic pollutants following 9/11,” said Dr. Philip J. Landrigan, chair of the Department of Community and Preventive Medicine at Mount Sinai. “We are continuing our monitoring and treatment program with support from the National Institute for Occupational Safety and Health.

"We encourage anyone who worked at Ground Zero, especially in the early days after Sept. 11, who has not yet been screened, to come for an evaluation. It is important that those who gave so heroically in the aftermath of the disaster be assured that they will be able to get all the medical care they need.”