On the 25th anniversary, New York posts 170,000 pages on Ground Zero air

Friday is the 25th anniversary of the 11 September 2001 attacks. In New York, Mayor Zohran Mamdani used the week to put more than 170,000 pages of city records online. The files concern air quality and official knowledge around Ground Zero in the months after the towers fell. He said previous leaders "lied and told them they were safe to breathe in toxic air." Comedian and advocate Jon Stewart stood with him at City Hall.

The portal cost more than $34 million, Mamdani said. It holds 68 boxes of papers found last year in a city office, archives from Rudolph Giuliani's mayoralty, records on Seven World Trade Center, and the Harding Memo written weeks after the attacks. That memo, sent toward then-deputy mayor Robert Harding, discussed lawsuits that could follow toxic exposure and the shortage of protective equipment. It also discussed legislation that might limit the city's liability.

The New York Times reviewed documents before release. A November 2001 audit, using figures from the Department of Environmental Protection, recorded elevated benzene near Ground Zero that month and higher ambient asbestos on Staten Island. Ten months after the attacks, asbestos was still being found around 15 John Street, less than a mile from the site. Those readings sit against the public assurances issued in 2001 that the air was safe to breathe.

Mamdani settled two lawsuits brought by 9/11 Health Watch as part of the release. More records are to be uploaded on a rolling basis. He said more people have now died of 9/11-related illness than died on the day itself. That comparison has been used by advocates for years. The new portal does not invent the illnesses. It shows what the city had in its own files while the first public statements were being made.

At the United Nations, a few miles north of the memorial pools, Antonio Guterres issued a statement on Thursday. He called the attacks an assault on humanity itself, named the nearly 3,000 dead from the United States and more than 90 other countries, and noted that 2026 is also 20 years since member states adopted the UN Global Counter-Terrorism Strategy. Independent human rights mandate-holders, in a separate text, argued that wars on terror had stretched international law. Those two UN products will be read together this weekend whether or not they were written to be.

Lower Manhattan is closed in layers for the Friday ceremony. FOX 5 described street shutdowns south of Canal Street and a heavy police presence. The National September 11 Memorial and Museum will run the familiar rite of names. Ipsos found that about half of U.S. adults still rank the attacks among the most important historic events of their lifetimes. For students who were not born in 2001, the day is a syllabus item.

The health file is the part of the anniversary that still produces new paper. The original death count is closed. The illness count is not. First responders, recovery workers and nearby residents have spent two decades in the World Trade Center Health Program. The Harding Memo and the 68 boxes do not treat those people. They show the city arguing with itself, in 2001 and 2002, about what to say and what to fear in court.

Mamdani's charge is blunt. The documents are not. They are audits, memos, contamination logs and correspondence. Readers can see benzene numbers in November and asbestos at 15 John Street the following summer. They can see a deputy mayor's office thinking about lawsuits before the pile had finished burning. That is the information gain of this anniversary week. The names in the pools are the same names as last year. The city's own archive is not.