Authorities knew air quality after September 11 attack was poor in New York

Mayor Zohran Mamdani announced on Tuesday that the city of New York will release 170,000 pages of previously undisclosed documents, showing that authorities at the time knew that the air quality after the September 11 terrorist attacks posed health risks, despite having assured the public and first responders that the air quality was safe. Ahead of the 25th anniversary of the attacks, the city published the documents on a public access portal, which includes reports on air quality and correspondence between New York officials. Mamdani allocated $34 million from the city budget for the creation of the portal with the records. Many documents were stored in 68 boxes in a city hall office, and many were only discovered last year by employees. The initial version available on the portal includes the document known as the "Harding Memorandum," sent to then-Deputy Mayor Robert Harding in 2001.