source: Medscape July 14, 2010
The emergency rescue workers who responded to the terror attacks and collapse of the World Trade Center on September 11, 2001, were exposed to a dense cloud of pulverized building materials and products of the combustion. Many of the first responders were rescue workers from the Fire Department of New York (FDNY) and the emergency medical service (EMS). For most of these workers (10,870 from FDNY and 1911 EMS workers), records of routine lung function tests that predated 9/11 were available. Therefore, it was possible to accurately determine the acute effects of the exposure that occurred after the attack.
In this article from Aldrich and colleagues, the long-term results of the workers’ exposures are detailed. For firefighters, the mean decline in lung function (FEV1) was 439 mL in the first year after exposure, most of which occurred in the first 6 months; for EMS workers, the corresponding loss was 267 mL. The losses were greater among workers who were at the scene on the first day and among those who accumulated more weeks and months working at the site after the event. Loss of lung function did not differ significantly between smokers and nonsmokers. Over the following 6 years, essentially none of the acutely lost lung function was recovered, and losses between 1 and 6 years after 9/11 occurred at about the same rate as in normal individuals.
The age-related loss of lung function in normal nonsmokers is between 20 and 30 mL of FEV1 per year, so the losses experienced by the rescue workers were huge — equivalent to the amount a healthy person would lose in 10 to 15 years — and far greater for some firefighters. Because no systematic measurements of lung function were made immediately after the exposure (they would have been done at the next routine spirometry within the next 6 months), it cannot be determined exactly when the losses occurred. The amount of loss of lung function was related to the extent of exposure, being worse among those with early and more prolonged exposure, as one would expect. But in previous studies, a short-term acute loss has usually been followed by rapid and sometimes full recovery. That this was not the case in the World Trade Center disaster might have been a result of the physicochemical characteristics of the exposure itself or, more likely, its intensity.
Another noteworthy feature of this event was that the use of respirators was apparently minimal in the first week after 9/11, a fact that undoubtedly contributed to the lung damage. Protective masks tend to be uncomfortable and impair breathing and are all too often neglected, especially when the work is heavy and hectic and the environment is hot. This study suggests that improvements need to be made in protective breathing equipment for those at risk for massive respiratory exposures. This applies particularly to firefighters, among whom the risk is obvious, but also to EMS workers.