Abstract

The terrorist attack on 9/11/2001, and subsequent rescue, recovery, and service restoration of the World Trade Centre disaster site in New York City, created an unprecedented and unique occupational and environmental exposure that affected a large and diverse group of rescue workers and volunteers. The workers were exposed to a mixture of poorly characterised inhaled toxicants. A variety of acute and chronic respiratory illnesses have been reported among all exposed workers, which are the subject of large scale ongoing investigation and follow up. The predominant WTC related chronic lower airway disorders have been clinically characterised as irritant-induced asthma, nonspecific chronic bronchitis, chronic bronchiolitis, and aggravated pre-existent chronic airway disease. In addition to those, several often limited case reports, case series, and small studies have suggested other associated lung diseases among those workers. Lung function surveillance, which demonstrated an exaggerated one time expiratory flow loss (about 500 ml), has shown an average expiratory flow decline in subsequent years that seems to follow age-related rates. This episode clearly invited reflection on the characterisation of chronic airway diseases, risk factors for respiratory health, and respiratory epidemiology methods.