The names read this Friday, in the 25th anniversary of the terrorist attacks on September 11 memorialize the 2,977 people killed in New York, at the Pentagon and near Shanksville, Pennsylvania, in 2001. But thousands of additional victims remain largely absent from the public accounting.
They were firefighters, police officers, paramedics, construction workers, and volunteers who participated in the rescue, recovery, and cleanup operations. They were also office employees, students, and residents who returned to Lower Manhattan after government officials assured the public that the air was safe.
Nearly 9,700 responders and survivors have reportedly died from illnesses associated with exposure to the toxic dust and smoke, according to figures cited ahead of the 25th anniversary. Cancer alone has been connected to almost 5,900 deaths.
Combined with those killed on September 11, the attacks and their aftermath have now claimed more than 12,000 lives. The precise secondary death toll remains difficult to establish because federal databases count deceased program members differently, and proving that an individual illness resulted from exposure can take years.
The broader trend, however, is unmistakable. More people have died in the years following 9/11 than were killed during the attacks themselves.
The federal World Trade Center Health Program now serves more than 145,000 responders and survivors. More than 57,000 program members have received certifications for cancer, while tens of thousands have been diagnosed with chronic sinus problems, gastroesophageal reflux disease, asthma, respiratory disorders, and post-traumatic stress disorder.
Those figures are expected to keep rising because some cancers and neurological conditions can take decades to appear.
The hidden toll gained renewed attention this week when New York City released approximately 170,000 pages of previously withheld records concerning air quality and the government's response after the towers collapsed.
The release resulted from litigation brought by the advocacy organization 9/11 Health Watch. According to The Guardian, the records include internal discussions about dangerous environmental conditions and the city's possible legal liability.
The papers raise new questions about what officials knew while rescue workers labored without adequate respiratory protection and residents were encouraged to return to apartments, schools and workplaces.
"People got sick because the leaders they trusted lied and told them they were safe to breathe in toxic air," New York City Mayor Zohran Mamdani said while announcing the records portal.
The collapse released pulverized concrete, glass fibers, asbestos, lead, mercury, silica and other hazardous materials. Fires continued burning beneath the debris for months, exposing workers to smoke and airborne contaminants during the prolonged search and cleanup.
Northwell Health has reported a 75% increase in the number of 9/11-related cancer cases treated through its World Trade Center program over the past three years. Its total rose from approximately 1,630 cases during the program's first decade to 2,445 by June 2026, according to the New York Post.
Recognition of these victims has come slowly. For the first time, the 2026 ceremony at Ground Zero added a seventh moment of silence to honor those who died from illnesses connected to the attacks and their aftermath.
Medical care and financial assistance have also required repeated political battles.
The World Trade Center Health Program provides monitoring and treatment without out-of-pocket costs for qualifying conditions. The separate September 11th Victim Compensation Fund compensates eligible responders, survivors and families for illness, economic losses and deaths.
The VCF was receiving approximately 750 new claims each month as of August 2026. It had received more than 112,000 claims, approved about 77,000 and issued more than $18.5 billion in award determinations. The fund is authorized through 2090.
Health coverage has proved less secure. Responders and survivors have repeatedly traveled to Washington to demand sufficient funding and staffing for the health program. Federal cuts and hiring restrictions caused delays in cancer certifications, treatment authorizations and enrollment appeals. Some patients reportedly waited close to a year for decisions.
Congress approved approximately $3 billion in additional funding in early 2026, while federal officials later authorized the hiring of 37 employees to help restore the program's workforce. Advocates nevertheless argue that permanent, dependable funding and adequate staffing remain essential as enrollment and treatment costs increase.
The expanding casualty list has transformed the meaning of the 9/11 death toll. It no longer describes only one terrible morning. It includes the rescue workers who ran toward Ground Zero, the laborers who cleared its wreckage and the families still fighting to have a loved one's illness recognized.
