What did City Hall know about post-9/11 air quality, when did they know it, and why didn’t they tell the public?
The City Council leadership is demanding answers to that critical question nearly 25 years after the Sept. 11, 2001, terrorist attacks destroyed the World Trade Center, killed more than 2,800 people, and left hundreds of firefighters and other recovery workers exposed to toxins that would later take their lives.
City Council Member and former Manhattan Borough President Gale Brewer (D-Manhattan) and City Council Speaker Julie Menin (D-Manhattan) on Thursday stood with other advocates for 9/11 survivors on the steps of City Hall on Thursday demanding a Department of Investigation (DOI) inquiry into post-9/11 air quality records while also urging the Mamdani administration to take quick action toward transparency.
The demand comes after attorneys unearthed a memo this week revealing that the city had been preparing for lawsuits related to air quality effects in the weeks following the Sept. 11, 2001, terrorist attacks. The memo, obtained by amNewYork, was uncovered by attorneys who have long been pushing the city to release documents related to post-9/11 air quality, some of whom were at Thursday’s press conference, where Brewer and Menin made their demands.
“It’s shameful, shameful, that the city hid this information, refused to disclose this information,” said Menin, who lived near Ground Zero when the attacks took place and played an instrumental role in helping Lower Manhattan rebuild in the years after. “It is unconscionable that the City of New York did not take responsibility for basically lying to not only first responders but to the whole downtown community.”
Why so many 9/11 firefighters, recovery workers became ill
The impacts of two hijacked airliners — American Airlines Flight 11 and United Airlines Flight 175 — into the World Trade Center’s 110-story twin towers set off fires that precipitated the collapse of both buildings within 102 minutes on Sept. 11, 2001. The collapses sent plumes of dust filled with asbestos, pulverized concrete and sheet rock, heavy metals, and other toxins into the air, covering Lower Manhattan and filling the lungs of rescue workers and others near the site that became known as Ground Zero.
Subterranean fires under the rubble of the Twin Towers burned for weeks as firefighters, police officers, iron workers, volunteers and other rescue workers dug through and cleared away debris in search of missing victims. Investigators later determined that the air quality at Ground Zero was far worse than officials at the time claimed.
In the years that followed, hundreds of people who worked at Ground Zero became sick from cancer and other illnesses tied to their exposure to the toxins that were in the air. In fact, more firefighters have died from 9/11-related illnesses (over 409 as of Sept. 11, 2025, according to the International Association of Firefighters) than in the actual 9/11 attack itself (343).
Andrew Ansboro, the president of the Uniformed Firefighters Association, the union “representing the health, safety and interests of New York City Firefighters,” said he hopes the city will bring transparency to firefighters and the public.
“They lied to limit their liability, and then they hid the records. They made a conscious choice to hide it instead of enforcing [Occupational Safety and Health Administration] rules,” Ansboro said at the press conference, accusing the city of not being “proactive” in the public health crisis that followed 9/11.
City Hall passed the buck for years, pols say
Brewer spearheaded legislation in 2024 that aimed to reveal how much the city knew about lethal toxins in the air following the attacks. The union representing FDNY firefighters has called on the city to release documents related to post-9/11 air toxins.
The council passed that legislation in July 2025, ordering a two-year DOI probe, but Brewer raised concerns on Thursday that the department is under-resourced. Former Mayor Eric Adams’ administration, and his predecessors, had refused to release the documents, pushing the deadline into Zohran Mamdani’s term.
“The importance of ethical oversight of city government has been front and center over the past few years,” Brewer said, urging Mayor Mamdani to allot more funding to DOI so it can complete its inquiry, which was approved by the City Council last year.
Spokespeople for Mayor Mamdani did not immediately respond to a request for comment. In previous statements, spokespeople for Mayor Mamdani have said the administration will look at the toxins records “more closely,” but did not commit to any official moves toward transparency.
Boxes of hidden secrets right under city’s noses
City officials said in November 2025 that 68 previously undisclosed boxes had been discovered in a Department of Environmental Protection facility after Brewer and the City Council enlisted the DOI to probe the matter.
The unearthed memo, sent to Deputy Mayor Robert Harding sometime in late 2001, reads that “there are approximately 35,000 potential plaintiffs as a result of the events of Sept. 11 and it is estimate (sic) that 10,000 would file a claim.”
The memo listed potential claims against the city, including “health advisories causing individuals to return to the area too soon (causing toxic exposure).”
Yet, the city’s public stance on air toxins at the time was starkly different. City and federal government officials assured New Yorkers that the air at Ground Zero was safe to breathe in the aftermath of the attacks.
The memo also raises concerns that “Rescue workers were provided with faulty equipment or no equipment (i.e., respirators).”
Jim Brosi, president of Uniformed Fire Officers Association Local 854, the union that represents FDNY fire officers including lieutenants, captains, and chiefs, said at the press conference that the union “couldn’t be more grateful” for the pressure from the electeds.
“[The memo] only revealed what we already knew, they were well aware of the toxins, they were well aware of the liability, and they were well aware of the impact it would have on us,” Brosi said, noting that the FDNY members are still dying from cancer related to post-9/11 toxins.
He urged Mayor Mamdani to do “the right thing” and release the documents that have long been kept from the public.
Tom Hart, president of Local 94 Operating Engineers, which represents HVAC workers, seconded the demands at Thursday’s press conference.
“The people that are getting sick need the proper answers,” Hart said. “It’s time for our new mayor to step up and do what he needs to do to get the information out to the people who really need it.”
U.S. Rep. Dan Goldman (D-Manhattan/Brooklyn) spoke in support of the investigation, hoping for “closure” for those impacted by 9/11-related air toxins.
“The idea that monetary and financial concerns would dictate the actions of the City of New York for 25 years is repulsive,” Goldman said. “The victims, the survivors, deserve to know what they went through, what they endured, what air they breathed.”
Goldman called on Mamdani to “do the right thing by the survivors and the victims, not by the financial coffers.”
