Can You Smell That? World Trade Center Workers Can't


People who worked at the World Trade Center site on and after 9/11 have an impaired ability to smell and to detect odors and irritants, according to new research from the Monell Center and other sources. An inability to detect irritants is critical, because individuals are not able to identify toxins and protect their lungs from harmful exposure.

The collapse of the World Trade Center released a complex mixture of smoke, gases, fumes, and dust, all of which greeted rescue, demolition, recovery, and clean-up individuals who were at the WTC site on 9/11 and during the days and weeks that followed. Investigators from the Monell Center and other institutions studied 102 people who had worked or volunteered at the WTC site to identify whether their exposure to the airborne pollutants had an impact on their ability to detect odors and irritants.

Nearly all (97%) of the study participants had worked on the WTC site during the week after the collapse and 44 percent were in lower Manhattan on 9/11. The researchers found that two years after the workers’ exposure, they had decreased sensitivity to odors and irritants as compared with similar workers who had not been on the WTC site. Nearly three-quarters of the WTC workers had an impaired ability to detect irritants, and 22 percent had difficulty detecting odors.


Although the ability to detect odors and irritants was compromised in most of the WTC workers, nearly all of them had not realized their deficit. Lead author Pamela Dalton, PhD, MPH, who is an environmental psychologist at Monell, noted that loss of this ability is important because “the sensory system that detects irritants is the first line of defense to protect the lungs against airborne toxic chemicals.” Without an operating detection system, “the reflexes that protect the lungs from toxic exposure will not be triggered.”

Several others studies have explored the health impact of the WTC tragedy on workers. One study, published in Chest, reported that the number of 9/11 responders who developed sarcoidosis, a rare type of lung condition, rose dramatically in the year after the attack.

Other studies report a high prevalence of WTC workers who developed respiratory conditions and post-traumatic stress disorder. A Mount Sinai School of Medicine study published in March 2010 reported evidence that WTC responders were more likely to have a condition in which their hearts cannot relax normally, which increases their risk for heart failure.

Dalton pointed out that the ability to smell odors is a protective function, because it allows individuals to detect leaking gas, smoke, and spoiled foods, among other potential dangers. Authors of the Monell Center study suggest that WTC workers should be evaluated regularly for their ability to smell and detect odors and irritants.

Izbicki G et al. Chest 2007 May; 131(5): 1414-23
Monell Center news release, May 18, 2010
Mount Sinai School of Medicine, news release March 16, 2010