25 years ago, on September 11, 2001, terrorist attacks on New York City’s World Trade Center left an everlasting impact on the nation, bringing renewed awareness around safety and security. However, as the 9/11 events unfolded, many New York City communities and neighboring regions unknowingly experienced unhealthy, unsafe air quality exposure.
New, previously undisclosed data demonstrates extremely high airborne pollutant levels during the events of 9/11, influencing health conditions and increasing cancer risks. By understanding new data correlations and airborne pollutants released during 9/11, pathways to renewed health security and clean indoor air quality can be achieved.
Airborne pollutant data is unearthed
On September 8, 2026, New York City Mayor Zohran Mamdani announced the release of over 170,000 undisclosed records relating to air quality following the September 11 terrorist attacks (1). The documents range in various research records from elevated airborne toxin levels directly after 9/11 to government air quality concerns.
“Now, close to 25 years later, more people have died from 9/11-related illnesses than were killed on the day itself,” Mamdani said in a press statement.
Separate research documents conducted by University of California, Davis researchers also found elevated levels of lung-penetrating, ultrafine particulate matter directly after the events of 9/11.
Thousands of first responders and local community members spent months after the event working on site, creating first-hand airborne pollutant exposure. According to the 9/11 Memorial, 352 chemical agents were found in the dust from the events of 9/11, which commonly became airborne through consistent construction and maintenance after the attack (2).
Which air pollutants were released on 9/11?
When the World Trade Center collapsed during 9/11, plumes of smoke and dust filled neighboring buildings, degrading indoor air quality. According to the Centers for Disease Control and Prevention (CDC), these smoke clouds contained a wide range of unhealthy airborne pollutants, including (3):
- Fiber glass
- Soot
- Silica dust
- Asbestos
- Pesticides
- Jet fuel
- Cement
Many airborne pollutants during 9/11 were released from crushed building materials and fuel emissions, which can linger and continuously impact breathing conditions. If left untreated or with prolonged exposure, many of these airborne pollutants can lead to health conditions and risks.
Silica dust and fiber glass are especially unhealthy, as long-term exposure can lead to silicosis, lung cancer, and respiratory irritation.
The prolonged impacts of air quality during 9/11
Despite the 25-year difference, the air quality and events of 9/11 continue to impact individuals today.
Airborne pollutants, such as silica dust and fiber glass, have been associated with long-term health risks that increase with continuous exposure. According to the 9/11 Memorial, 49,000 individuals have been diagnosed with certified WTC-related cancers, and at least 140,000 people across all 50 states are registered in the World Trade Center Health Program. Breast, prostate, and lung cancer are found to be the most common among 9/11 survivors.
These health concerns show no signs of slowing down. According to U.S. News, from 2021 to 2026, about 35% more 9/11 survivors have enrolled in government medical-care programs, and roughly half are being treated for cancer-related conditions (4).
Even at places of remembrance like the 9/11 Museum Workshop, air quality issues continue as chemical off-gassing from historical artifacts can pose health and safety concerns.
The takeaway
September 11 brought a national spotlight on personal safety, health protection, and community connections. As new data documents are unearthed, air quality and airborne pollutants are brought into a new light, further detailing the health effects and environmental conditions that occurred on that day.
By increasing air quality awareness and healthy breathing environments, new pathways to medical recovery and economic rebuilding can be established.
