Epidemiology of Respiratory Outcomes among World Trade Center (WTC) Disaster Workers: A Review of the Literature Ten Years after the September 11, 2001 Terrorist Attacks

Background: In the aftermath of the September 11, 2001 terrorist attacks, thousands of workers participated in rescue, recovery, and cleanup activities at the World Trade Center (WTC) site in lower Manhattan. The collapse of the WTC resulted in the release of a variety of inhalation toxicants. To date, respiratory health outcomes have been among the most examined health outcomes in studies of WTC workers.

Methods: A systematic review of the literature on health outcomes among WTC workers was undertaken to 1) identify risk factors and 2) describe the course of new-onset respiratory outcomes after September 11, 2001. Relevant studies were identified in PubMed, using the Medical Subject Headings (MeSH) term “World Trade Center Attacks, 2001".

Results: A total of eighteen articles that fit the inclusion criteria were identified. Fourteen studies were cross-sectional, while four studies employed a longitudinal study design. Independent risk factors for respiratory outcomes included exposure the WTC "dust cloud" on September 11, 2001, early arrival date at the WTC site, exposure to the debris pile at the WTC site, and longer duration of work after September 11, 2001. Limitations of WTC worker studies included participation bias, exposure misclassification, and limited information on covarying factors.

Conclusions: Ten years after the September 11, 2001 WTC disaster, longitudinal studies of WTC workers have been essential in investigating the respiratory health consequences of WTC exposure. Epidemiologic studies along with continued medical surveillance will be vital in understanding the long-term respiratory burden associated with occupational exposure to the September 11, 2001 WTC disaster.