That's in addition to the 343 FDNY members killed on Sept. 11, 2001.
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SEE ALSO: 9/11 Timeline: How the September 11 attacks unfolded
Each year, first responders who've died from illnesses related to the attacks are honored as their names are added to the World Trade Center memorial wall at FDNY headquarters.
"Our Department made a solemn promise to never forget the bravery and sacrifice of the 343 members who gave their lives on September 11th, and the growing list of heroes who have died due to illnesses related to their courageous work throughout the rescue and recovery effort," said New York City Fire Commissioner Daniel A. Nigro. "Though we are unable to join in person this year to remember these 27 extraordinary individuals, we still pause to honor that promise by ensuring their memory lives on with their inclusion on our World Trade Center memorial wall."
In addition to firefighters who were on the scene that day, other first responders have not been immune to sickness and death.
The NYPD has lost more than 200 former and current officers because of related diseases since 2011, and more than 500 have related cancers.
In 2018, the FBI reported an increase in the number of agents who had died due to 9/11-related illnesses, ABC News reported.
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Those numbers have only gone up since last year. According to the World Trade Center Health Program, 3,496 deaths have been attributed to a variety of illness related to the attack's aftermath.
That number includes those who responded to the Pentagon and Shanksville, Pennsylvania.
An estimated 400,000 people were exposed to toxic dust and other debris when the twin towers were reduced to rubble.
This year's COVID-19 pandemic has taken an even greater toll on survivors and first responders, as at least 42 of them have died due to complications from the virus.
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