Felicia Dunn-Jones died of lung disease five months after Sept. 11, and last year her family asked that the city's medical examiner add her name to the death toll.

New York City Chief Medical Examiner Charles Hirsch refused, writing back that his office could not link her death to the exposure "with certainty beyond a reasonable doubt."

That changed Wednesday, when Dunn-Jones was added to the medical examiner's list of attack victims. It marked the first time the city has officially linked a death to the toxic dust caused by the World Trade Center's collapse.

The 42-year-old attorney was caught in the dust cloud while fleeing the collapsing towers on Sept. 11, 2001. She died of sarcoidosis, a disease that causes inflammation and scarring in the lungs, on Feb. 10, 2002.

In explaining the reversal, Hirsch cited "accumulated scientific research" that concluded exposure to trade center dust can cause or contribute to sarcoidosis.

"Mrs. Dunn-Jones' exposure to World Trade Center dust on 9/11/01 contributed to her death and it has been ruled a homicide," Hirsch wrote. "Mrs. Dunn-Jones has now been added to the list of people who died as a result of the collapse of the World Trade Center towers."

The city puts the Sept. 11 death toll at the trade center at 2,750. Dunn-Jones will be listed on the Sept. 11 memorial when it opens in 2009, a spokeswoman for the World Trade Center Memorial Foundation said.

A class-action lawsuit has claimed that dozens of deaths have been caused by exposure to toxic trade center dust.

A study published this month by a Fire Department of New York doctor linked sarcoidosis definitively to exposure to the toxic plume that enveloped lower Manhattan after Sept. 11. It found that firefighters contracted the disease at a much higher rate after the attacks than before.

New York lawmakers seeking federal funding for Sept. 11 health issues said more names should be added to the list.

"Sadly, we have known that Felicia is not alone and that others have died from ailments caused by 9/11," said U.S. Rep. Carolyn Maloney, D-N.Y. "Dr. Hirsch must review the cases of other 9/11 heroes who, like Felicia, died in the prime of their lives."

A New Jersey medical examiner last year ruled that the January 2006 death of a retired police detective, 34-year-old James Zadroga, was "directly related" to his work at ground zero on and after Sept. 11.

Zadroga's father, Joseph Zadroga, said his son also suffered from sarcoidosis and that he and many others should be added to the list of victims with Dunn-Jones.

"I think that anybody that passes as a result of 9/11 should be listed on the wall," he said.

Dunn-Jones will be listed on the Sept. 11 memorial with the names of 2,973 people killed on Sept. 11 in New York, Pennsylvania and Washington, D.C., memorial foundation spokeswoman Lynn Rasic said.

Mayor Michael Bloomberg, who chairs the foundation, said his "thoughts and prayers are with the Dunn-Jones family."

"It is on their behalf and on behalf of all those affected by 9/11 that we are now building a memorial that remembers and honors the thousands of innocents that died," he said.