9/11 toxic air files show NY withheld data, mayor says

New York Mayor Zohran Mamdani said Tuesday that newly released documents show the city did not disclose all it knew about toxic air after the September 11 attacks.

The city released about 170,000 pages of documents online covering health concerns, air quality and New York's response to the attacks. Mamdani said the documents showed what the city knew about toxic air around Ground Zero, when it knew it and how it acted to limit liability.

The release comes ahead of the 25th anniversary of the September 11, 2001, attacks, which killed 2,977 people in the United States, mostly in the collapse of the Twin Towers in New York. More than 9,400 people have died from illnesses linked to exposure to the area in the years since, according to a federal medical monitoring program.

The publication is part of an agreement with 9/11 Health Watch, a victims' advocacy group that had taken legal action to compel the city to make the documents public. Benjamin Chevat, the group's director, said four mayoral administrations had kept documents from the public, the US Congress and the City Council for 25 years while city officials continued saying the air was “safe and acceptable”.

Asked about officials who withheld information, Mamdani said the issue crossed “a multitude of those that New Yorkers have trusted.” He added: “People got sick because the leaders they trusted lied and told them they were safe to breathe in toxic air.”

Additional documents are due to be published online in waves over the next 12 months. New York City's chief counsel Steven Banks said some of the released documents concern discussions during Rudy Giuliani's administration about legal liability and health risks. Another document concerns information provided by Congressman Jerry Nadler during Michael Bloomberg's tenure about air-quality concerns from Lower Manhattan residents.