Respiratory Symptoms and Conditions

Exposure to the toxic 9/11 dust increased the risk of developing respiratory issues among first responders and recovery workers. Rescue, recovery, and cleanup workers who arrived early at the WTC site, or worked at the WTC site for long periods of time, had higher levels of respiratory impact. Research also highlights that steep declines in pulmonary function among firefighters diagnosed within one year of 9/11 have largely persisted, even among those who never smoked. It is estimated that four-times as many firefighters and twice as many EMS workers had below-normal lung function for their ages six to seven years after 9/11. Lung function declines were greater for current smokers than for non-smokers. The prevalence of symptoms correlates with the degree of WTC site exposure, and both epidemiological and clinical studies demonstrate substantial co-morbidity of respiratory illness and mental health conditions in WTC-exposed groups. Ten years after the 9/11 attacks, lower respiratory symptoms (LRS) such as coughing, wheezing, trouble breathing, or using an inhaler still affected first responders and recovery workers. One-half of those with persistent LRS also had PTSD, depression, or generalized anxiety disorder. Respiratory illness and mental health conditions often occurred together in responders exposed to disaster.^{Reference Wisnivesky, Teitelbaum and Todd6,Reference Luft, Schecter and Kotov9,Reference Izbicki, Chavko and Banauch12,Reference Niles, Webber and Gustave14–Reference Mauer, Cummings and Hoen41}

Cancer

Several WTC cancer studies based on diagnoses have been published. This research suggests that long-term monitoring of cancer occurrence among WTC-exposed individuals is warranted. The FDNY found that nearly 9,000 firefighters with WTC exposure may be at greater risk of cancer than firefighters who were not exposed, and the WTC Health Program identified higher-than-expected prostate and thyroid cancer rates among rescue and recovery workers enrolled in the Program when compared to overall rates in New York, New Jersey, Connecticut, and Pennsylvania (USA), where the majority of workers lived. ^{Reference Miller42–Reference Moline, Herbert and Crowley44}

In two articles published in the June 2018 issue of the journal JAMA Oncology (American Medical Association [Chicago, Illinois USA]), researchers reported that firefighters who worked at the WTC site from September 11, 2001 to July 25, 2002 (the day the site closed to recovery efforts) were exposed to unprecedented environmental toxins and, as a result, have increased risks of many types of cancer, including prostate and thyroid cancer, melanoma, and multiple myeloma.^{Reference Landgren, Zeig-Owens and Giricz45,Reference Singh, Zeig-Owens and Moir46} In the first study, researchers isolated a group of white male firefighters with a mean age of 50 years who were at the WTC site in the days and months after 9/11. They then compared their projected risk of cancer compared to average New Yorkers of the same race, gender, and age. The researchers reported that WTC-exposed firefighters could expect a modestly higher number of cancers, specifically prostate, thyroid, and the skin cancer melanoma.

In the second study, researchers compared multiple myeloma and its precursors (non-cancerous cells that could be evidence of future disease) to a population of controls. Results suggest that the rate of multiple myeloma precursors, specifically those correlated with a rare form of light-chain precursors, was elevated among WTC first responders compared to controls who were demographically similar. Taken together, these recent publications provide important lessons that will help the fire department treat existing diseases and plan for its future.

But the results are not without controversy.^{Reference Cummins47} Firefighting is a dangerous profession and firefighters are exposed to acute risks on a daily basis. Furthermore, they are routinely exposed to known and suspected carcinogens at much higher rates than the average person. On 9/11, every available firefighter in the greater New York City area rushed to the scene. In the immediate aftermath, 413 emergency responders died, including 343 firefighters.^{Reference Smith and Burkle1} But the deaths have not stopped there. They have continued throughout the 17 years since the attacks in the form of cancers and other illnesses.

Previous research has called attention to these risks, many led by David Prezant, the Chief Medical Officer of the FDNY and a professor of pulmonary medicine at Albert Einstein College (Bronx, New York USA). On September 12, 2002, just one year after the WTC attack, Prezant and his colleagues published one of the first comprehensive studies of the health challenges associated with responding to 9/11 in the New England Journal of Medicine (Massachusetts Medical Society [Waltham, Massachusetts USA]) on “Cough and Bronchial Responsiveness in Firefighters at the World Trade Center Site.”^{Reference Prezant, Weiden and Banauch39}

Heart Disease

The World Trade Center-Heart study published in 2018 includes 6,841 non-firefighter workers and untrained volunteers (83% men; average age 51). This includes staff from the medical examiner’s office who were involved with the processing of human remains, and the Port-Authority Trans-Hudson Corporation (New York and New Jersey USA) and others who were engaged in the cleanup, recovery, service restoration, and other tasks in the months following the attack. The research highlights that first responders and recovery workers who suffered more than one injury on 9/11 and have 9/11-related PTSD are three-times more likely to develop heart disease as people who were not injured and did not have PTSD. Male rescue and recovery workers are at higher risk for subsequent heart-related hospitalization. Those who developed PTSD faced more than double the risk of a heart attack and stroke compared to those who worked on New York City’s WTC site but did not develop PTSD. Although this study cannot prove a cause-and-effect relationship, it should be noted that PTSD can trigger a number of biological responses that might explain the association between PTSD and heart disease and stroke.^{Reference Jordan, Stellman and Morabia48,Reference Remch, Laskaris and Flory49}

A major strength of this study is that it examined the impact of PTSD on heart disease in people 11 to 15 years after the 9/11 attacks. This meant that the participants were entering the age group at which heart disease risk and events rise dramatically. Another strength of the study was that it provided four years’ worth of data on those subjects. However, despite the large sample size, the study may not provide an accurate cross-sectional representation for the approximately 90,000 first responders and recovery workers who responded throughout the eight months following the WTC attack.

Most recently, a 2019 study of New York City firefighters conducted by the Albert Einstein College of Medicine, the Montefiore Health System (Bronx, New York USA), and the FDNY found that exposure to WTC dust is associated with a significantly increased long-term risk of cardiovascular disease (CVD). The study found that those who arrived first at the WTC site when the air-borne dust was thickest have a 44% increased risk of CVD compared to those who arrived later in the day. The increase in risk was significant, even taking into account known CVD risk factors such as age, hypertension, elevated cholesterol, diabetes, and smoking.^{Reference Cohen, Zeig-Owens and Joe50}

PTSD

Approximately 20% of men and 26% of women who responded to the WTC site on and after the 9/11 attacks developed PTSD, which is at least twice the rate expected in the general population.^{Reference Pietrzak, Feder and Singh51} Rescue and recovery workers who got to the WTC site on or soon after 9/11 were more likely to develop PTSD than those who arrived later. The longer someone worked at the site the greater the risk for PTSD. Rescue and recovery workers from non-emergency occupations, such as construction and sanitation workers, also suffered higher rates of PTSD than emergency responders. Responders who experienced trauma before or after 9/11, such as losing a job after the attacks, or urban or domestic violence, were at increased risk for developing PTSD. Ten years after the attack, 15% of World Trade Center Health Registry enrollees had PTSD symptoms. Importantly, PTSD was more likely to persist or get worse in people who were unable to get mental health treatment, had high 9/11-related exposure, were unemployed, or had little social support. Untrained first responders who engage in activities surrounding the aftermath of disasters are more likely to struggle with psychological challenges following their work than first responders who have received training.^{Reference Clouston, Kotov and Pietrzak8,Reference Friedman, Farfel and Maslow10,Reference Ly11,Reference Webber, Lee and Soo15,Reference Pietrzak, Schechter and Bromet52–Reference Cone, Li and Kornblith67}

Female police officers recruited and trained in exactly the same way as their male colleagues had much higher rates of PTSD following 9/11.^{Reference Bowler, Han and Gocheva55} This result is in contrast to previous studies conducted with Gulf War veterans and police officers in general, which found no gender differences. Analyzing information collected from more than 4,000 police responders to assess the prevalence of PTSD, it was found that around 14% of female officers had PTSD compared with approximately seven percent of male officers.^{Reference Bowler, Han and Gocheva55}

Other Mental Health Challenges

A sample of paramedics and EMTs who responded to the 9/11 terrorist attacks reported a range of long-term psychosocial challenges, including PTSD, anxiety, depression, stress, survivor guilt, insomnia, relationship breakdowns and impact on family support systems, and addictive and risk-taking behaviors.^{Reference Smith and Burkle68} Ten years after the attacks, 15% of World Trade Center Health Registry enrollees who were responders reported depression and 10% reported both depression and PTSD. Five to six years after the attacks, responders who had the greatest exposure to the events of 9/11 or who had 9/11-related PTSD were around twice as likely to drink four to five drinks at a time (binge drinking). Smokers with mental health conditions were less likely to quit smoking, and needed additional support to do so.^{Reference Pietrzak, Schechter and Bromet52,Reference Bowler, Kornblith and Li58–Reference Bowler, Harris and Li60,Reference Feder, Mota and Salim63,Reference Zvolensky, Farris and Kotov64,Reference Schwarzer, Bowler and Cone69}

The research identified by this systematic literature review documents both distinct conditions and symptoms. What they both represent are unique challenges, which are characteristic to 9/11 and a rapidly changing world. Consequently, this review uses the word “challenges” instead of “impacts,” as impact has primarily physical connotations only. The term “challenge” is more inclusive. The term “condition” has been used where there is a specific physical diagnosis made. As a final reflection, 9/11 is quite unique as a product of the times, both in terms of the complexity of the modern building and what toxins it produced, to the massive physical and mental health challenges it resulted in for such a large portion of the population.