New York City on Tuesday released nearly 170,000 pages of previously hidden records related to the aftermath of the September 11th terrorist attacks. The documents detail health and air quality concerns and suggest that city officials may have misled the public about the toxic risks present in Ground Zero's air.
The release follows a settlement in lawsuits brought by the 9/11 Health Watch watchdog group and represents a significant achievement for advocates who have long raised concerns about air toxins following the collapse of the World Trade Center towers.
"It is time for this painful chapter to end," said Mayor Zohran Mamdani at a City Hall press conference, joined by Jon Stewart and other advocates for 9/11 survivors and first responders. "These are documents that show what the city knew about toxic air around Ground Zero, when they knew it and how they acted to limit liability." He added that the records contain details about the Department of Environmental Protection's response, the prevalence of asbestos found in tested areas, and will aid New Yorkers in accessing necessary healthcare.
Among the released files is a critical memo from October 2001, often referred to as the "Harding memo." This document, written by New York City lawyers to Bob Harding, then deputy mayor for economic development under Mayor Rudy Giuliani, acknowledged the city's potential liability for tens of thousands of lawsuits stemming from toxic exposure.
Additional records include "68 boxes" of health-related documents from 9/11 that were only located in 2025. The newly available documentation is now accessible through an online portal.