New York City officials recently released more than 170,000 pages of previously unavailable records In commemoration of the 25th anniversary of the September 11 attacks on the World Trade Center.
These documents include documented concerns about asbestos and other carcinogenic materials, including what city officials knew and how they responded to the scene. The Harding Memo, the “68 boxes” of records not located until 2025 and other records related to the World Trade Center 7 incident are also among the released documents.
The documents shed light on the city’s response to the toxic air around Ground Zero. Mamdani said they show “what the city knew about the toxic air around Ground Zero, when they knew it and how they acted to limit liability.”
Mayor Mamdani has promised that his office will release more of these documents as part of his commitment to governmental transparency: “The 170,000 pages posted today are only the first release. This is only the beginning. Over the coming months, we will continue to release updates to the portal.”
The release follows new health data showing that illnesses linked to 9/11 exposure continue to be diagnosed and treated 25 years after. They also provide a clearer picture of the longterm respiratory, cardiovascular and cancer risks related to exposure to Ground Zero and nearby sites.
9/11 Health Effects Are Still Unfolding
Cancer is one of the main long-term health effects linked to 9/11 exposure. However, the full health impact of 9/11 are still unfolding.
Northwell Health, one of the seven federally funded New York Metro organizations treating World Trade Center responders, recorded a 75% increase in newly certified 9/11-related cancer cases.
The program, which provides monitoring and treatment for first responders and survivors, reported a rise in case cases from 177 in 2023 to 235 in 2025. The program also reported 132 new cases in the first half of 2026, bringing the total to 811 new cases in 42 months. The report identifies skin and prostate cancers as the most common cancers diagnosed among responders and survivors, followed by breast and urinary tract cancers.
Findings from the Fire Department of the City of New York also show the longterm health toll. In total, 10,562 FDNY members have received diagnoses for at least one 9/11-related physical condition, including 4,257 who have received cancer certification. Many of these members encountered dust, gases, chemicals and other contaminants during the rescue and recovery effort.
Cancer’s long latency is a primary reason new cases continue to surface years after exposure. Some malignancies can take decades to manifest after exposure to carcinogens. This timing is why the World Trade Center Health Program establishes minimum latency thresholds for cancer certification, before formally recognizing a member’s condition as associated with 9/11-related exposure.
Effects Extend Beyond First Responders
The long-term health effects of 9/11 extend far beyond first responders and immediate survivors. Non-responder exposure also continued beyond September 11. People in the area were exposed to dust and other contaminants in the days and months that followed, including pulverized concrete, glass fibers, lead, asbestos and other chemicals that settled in homes, schools and buildings.
Public health research has documented exposures among people who lived and worked near Ground Zero. Children also faced exposure, but researchers still know less about how exposure at a young age may affect health later in life.
Effects On Youths
That gap is now becoming a major focus of federal research. Congress directed the World Trade Center Health Program to establish a Youth Research Cohort for people who were 21 or younger at the time of their exposure, including those whose mothers were pregnant with them. Federally funded research is also examining the long-term health effects of 9/11 exposure among people who were 21 or younger at the time of the attacks, including those exposed in utero.
Researchers have documented cancers among young people exposed to 9/11 toxins. A study on the WTC Environmental Health Center enrollees who were ages 0 to 30 on 9/11 identified 278 cancer diagnoses across 23 cancer types, including cancers considered rare for that age group. Many of those patients did not have traditional cancer risk factors such as tobacco use.
A Columbia University’s Center for Children’s Environmental Health study on children exposed to the environmental aftermath of 9/11 before birth found found associations between exposure to pollutants, including polycyclic aromatic hydrocarbons,, and reduced fetal growth, including lower birth weight and smaller head circumference. Other longitudinal research has linked prenatal exposure to environmental pollutants with poorer neurodevelopment, respiratory problems, asthma and behavioral and cognitive effects in childhood.
A study from Columbia University’s Center for Children’s Environmental Health on children exposed to the environmental aftermath of 9/11 before birth found associations between exposure to pollutants, including polycyclic aromatic hydrocarbons, and reduced fetal growth, including lower birth weight and smaller head circumference.
Other longitudinal research has linked prenatal exposure to environmental pollutants with poorer neurodevelopment, respiratory problems, asthma, and behavioral and cognitive effects in childhood.
Clinician’s Role In Connecting Patients To 9/11 Care
The 25-year health legacy of 9/11 can still show up in the exam room. The CDC and New York City health officials advise clinicians to ask patients about their 9/11 exposure history, particularly if they have respiratory symptoms, chronic rhinosinusitis, gastrointestinal conditions, cancer, or certain mental health conditions.
Clinicians also play a role in connecting patients to care they may not know exists. Clinician can refer patients with 9-11 related conditions to the WTC Health Program provider for evaluation. Program physicians can then request certification when they determine that a condition meets the program’s medical and exposure criteria. Once certified, eligible patients can receive medically necessary treatment for that condition through the program with no out-of-pocket costs.
Patients not enrolled in the program could have screenings covered by their regular insurance. However, elevated risk from 9/11 exposure does not automatically guarantee coverage for additional screening through a private insurer. Coverage will depend on the individual policy and the patient’s medical history.
That distinction matters even decades after the attacks because the WTC Health Program provides a direct path to specialized care for eligible patients with covered conditions. By asking about 9/11 exposure, clinicians can help identify high-risk patients who may benefit from the program rather than relying solely on standard insurance pathways, which can involve additional administrative requirements and out-of-pocket costs.
