Lessons learned from the exposure of 9/11 survivors to toxic dust and the chronic health problems that followed

The September 11 terrorist attack on the World Trade Center in New York City resulted in the loss of 2,753 people in and around the Twin Towers. After the attack, more than 1,000,000 rescue workers and recovery workers from all states in the United States – as well as some 400,000 residents and other workers around Ground Zero – were exposed to a cloud of toxic dust that fell in the form from a thick layer of ghostly ash, then suspended in the air for more than three months.

The World Trade Center dust plume, or WTC dust, consisted of a dangerous mixture of dust and particles of cement, asbestos, and a class of chemicals called persistent organic pollutants. These include carcinogenic dioxins and polycyclic aromatic hydrocarbons, or PAHs, which are by-products of fuel combustion.

The dust also contained heavy metals known to be toxic to the human body and brain, such as lead – used in the manufacture of flexible electrical cables – and mercury, which are found in float valves, switches and fluorescent lamps. The dust also contained cadmium, a carcinogen toxic to the kidneys that is used in the manufacture of electric batteries and pigments for paints.

Polychlorinated biphenyls, chemicals of human origin used in electrical transformers, were also part of the toxic stew. PCBs are known to be carcinogenic, toxic to the nervous system and disruptive to the reproductive system. But they have become even more harmful when they are incinerated at high temperatures by the combustion of the fuel in the jets, and then carried by very fine particles.

The dust from the WTC was made up of both “big” particles and very small, fine and ultrafine particles. These particularly small particles are known to be highly toxic, especially to the nervous system since they can travel directly through the nasal cavity to the brain.

Many first responders and others directly exposed to the dust developed a severe and persistent cough that lasted an average of a month. They were treated at Mount Sinai Hospital and received treatment at the Occupational Medicine Clinic, a well-known center for occupational diseases.

I am an occupational health physician who began working directly with 9/11 survivors in my role as Data Center Director for the WTC Mount Sinai Health Program from 2012. This program collects data, as well as monitors and supervises public health. WTC rescue and recovery workers. After eight years in this role, I moved to Florida International University in Miami, where I plan to continue working with 9/11 responders who move to Florida at retirement age.

From acute to chronic illnesses after the first “acute” health problems faced by responders on September 11, they quickly began to experience a wave of chronic illnesses that continue to affect them 20 years later. The persistent cough has given way to respiratory illnesses such as asthma, chronic obstructive pulmonary disease (COPD), and upper respiratory tract illnesses such as chronic rhinosinusitis, laryngitis, and nasopharyngitis.

The litany of respiratory illnesses also puts many at risk for gastroesophageal reflux disease (GERD), which occurs at a higher rate in WTC survivors than in the general population. This condition occurs when stomach acids enter the esophagus, or digestive tract, which connects the stomach to the throat. Due to respiratory or digestive tract disorders, many of these survivors also suffer from sleep apnea, which requires additional treatment.

Further compounding the tragedy, about eight years after the attacks, cancers began to appear among 9/11 survivors. These include tumors of the blood and lymphoid tissues such as lymphoma, myeloma and leukemia, which are well known to affect workers exposed to carcinogens in the workplace. But survivors also suffer from other cancers, including breast, head and neck, prostate, lung and thyroid cancers.

Some have also developed mesothelioma, an aggressive form of cancer linked to exposure to asbestos. Asbestos was used early in the construction of the North Tower until public advocacy and a wider awareness of its health dangers ended its use.

And the psychological trauma suffered by 9/11 survivors has left many with lingering mental health issues. A study published in 2020 found that of more than 16,000 WTC responders for whom data was collected, nearly half reported a need for mental health care, and 20% of those directly affected developed post-traumatic stress disorder.

Many have told me that the contact they had with human body parts or with the murder scene and the tragic days that followed left a permanent mark in their lives. They are unable to forget the pictures, and many suffer from mood disorders as well as cognitive impairment and other behavioral problems, including substance use disorders.

An aging generation of survivors now, 20 years later, these survivors face a new challenge as they age and move into retirement – a difficult life transition that can sometimes lead to a decline in mental health. Before retirement, the daily rhythm of professional activity and a regular schedule often help to keep the mind occupied. But retirement can sometimes leave a void – one that, for 9/11 survivors, is too often filled with unwanted memories of the sounds, smells, fear and despair of that terrible day and the days that followed. Many survivors have told me they don’t want to go back to Manhattan and certainly not to the WTC.

Aging can also be accompanied by forgetfulness and other cognitive challenges. But studies show that these natural processes are accelerated and more severe in 9/11 survivors, much like the experience of war zone veterans. This is a worrying trend, but especially since a growing body of research, including our own preliminary study, is finding links between cognitive impairment in 9/11 responders and dementia. A recent Washington post The article explained how 9/11 survivors experience these dementia-like conditions in their 50s – much earlier than usual.

The COVID-19 pandemic has also taken its toll on those who have already suffered from September 11. People with pre-existing illnesses were at much greater risk during the pandemic. Unsurprisingly, a recent study found a higher incidence of COVID-19 among WTC responders from January to August 2020.

In honor of 9/11 survivors, the health risks posed by direct exposure to acrid dust were underestimated at the time and poorly understood. Appropriate personal protective equipment, such as P100 half-face masks, was not available at this time.

But now, 20 years later, we know a lot more about the risks – and we have much wider access to protective gear that can keep disaster responders and recovery workers safe. Yet all too often I find that we have not learned and applied these lessons.

For example, in the aftermath of a condominium collapse near Miami Beach in June, it took days before P100 half-face respirators were fully available and made mandatory for responders. Other examples around the world are even worse: a year after the Beirut explosion in August 2020, very little action has been taken to investigate and manage the consequences on the physical and mental health of responders and the affected community.

An equally dire situation arises immediately after a chemical fire in July 2021 in Durban, South Africa.

Applying the lessons learned from September 11 is an extremely important way to honor the victims and the brave men and women who took part in the desperate rescue and recovery efforts in those terrible days.