New York City officials a quarter century ago knew the potential dangers that lurked in the air after the 9/11 attacks, according to new documents released days before the anniversary.
Mayor Zohran Mamdani announced the release of more than 170,000 records about the air quality after the September 11, 2001 attacks, which showed that city officials knew that it was dangerous to breathe the air near Ground Zero.
One of the released documents is known as the “Harding Memo,” sent by then-Deputy Mayor Robert Harding, who said thousands of lawsuits could follow from exposure to the post-attack air and the lack of safety equipment. It also spelled out legislative moves that could limit the city’s legal liability, CNN reported.
The memo from Michelle Goldstein to Harding with the subject, “Legislative Alternatives to Limit the City’s Liability relating to 9/11/01″ reads in part: “According to the Law Department, there are approximately 35,000 potential plaintiffs as a result of the events of September 11 and it is estimate that 10,000 would file a claim.”
The memo is on the 9/11 portal, announced by Mamdani using the document’s subject (“Legislative Alternatives to Limit the City’s Liability relating to 9/11/01″).
Potential lawsuits, according to the memo, were:
- “Health advisories caused individuals either to return to the area too soon (causing toxic exposure or emotional harm) or too late (causing economic hardship).
- “Rescue workers were provided with faulty equipment or no equipment (i.e. respirators).”
- “Unsafe workplace (OSHA, FEMA, Labor Law)”
- “Inadequate clean up”
The New York Times reported that 10 months after the attack, health officials still found evidence of asbestos in the air a half mile from Ground Zero.
The documents include 170,000 pages of air quality reports, contamination records and memos between New York officials that were held in 68 boxes stored since 2001 and discovered in 2025, the newspaper said. The documents unveiled this week are a “fraction” of reports and memos, and “many more are presumably absent.”
Still, more documents will be released after reviews and redactions are complete.
The advocacy organization, 9/11 Health Watch, sued for the documents’ release.
“As the years pass and the human toll grows, we reckon with the cost of September 11th whenever another New Yorker is stolen from us too soon,” Mamdani said on Tuesday, according to CNN. “Now, close to 25 years later, more people have died from 9/11-related illnesses than were killed on the day itself.”
Many have died from lung and blood cancer, as well as heart and respiratory disease, the Times reported.
“People got sick because the leaders they trusted lied and told them they were safe to breathe in toxic air,” Mamdani said.
The mayor was joined by 9/11 families and Jon Stewart, who has demanded increased transparency and resources for first responders and survivors of the attacks.
“There was poison in the air, and on the ground, and in the window sills, and in your air conditioners and covering your pets and your clothes, and it stayed there for months. Everyone knew. Now it’s very clear that the city knew as well,” “The Daily Show” host said.
Ben Chevat, 9/11 Health Watch executive director, said the documents showed that officials knew about the danger “even as city officials continued messaging to the public that the air was ‘safe and acceptable,’” the Times reported.
The release may also open the door to new or amended lawsuits and allow more people to access the Sept. 11 victim compensation funds, according to the newspaper.
One woman, Marisa Ramírez de Arellano, wrote that she had “scooped up dust from coffee table into a paper bag,” after the attacks. She “also started to clean the floor with wet paper towels,” which she called “mostly futile.”
This week, the now-80-year-old woman told the Times she had sought out treatment from an allergist and pulmonologist, who feared that she had lung damage from 9/11.
She said she “didn’t realize that very lightweight dust that was coming in was as bad for human beings as it turned out to be.” She left her apartment when firefighters evacuated her, but when she returned several weeks later, she was told the air was safe to breathe. Ramírez de Arellano said she doubted it, especially after a hazmat team dug up grass near her home.
They dug several inches down and took it all away and replaced it with new dirt, new sod, new grass,” she said. “And I thought, if they were thinking the grass is contaminated, then what are we all breathing?”
Rep. Jerrold Nadler, who represented the area around Ground Zero at the time, said this week that he tried to convince then-Mayor Rudy Giuliani and then-Gov. Michael Bloomberg to release any air quality reports they had for the recovery sites.
“They knew about the air quality, and they essentially did nothing about it,” Nadler told the Times. “I suspect that all they cared about was getting Wall Street reopened, and they didn’t give a damn about the health of the people down there.”
Neither Giuliani nor Bloomberg commented when asked by the Times this week.
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