The decision by Dr. John Howard, director of the National Institute for Occupational Safety and Health and administrator of the World Trade Center Health Program, approved all of the 14 cancers recommended by the program's advisory committee.

"We recognize how personal the issue of cancer and all of the health conditions related to the World Trade Center tragedy are to 9/11 responders, survivors and their loved ones," he said in a statement.

The decision comes as welcome news for members of the emergency services and people who lived or worked in downtown Manhattan and developed cancers after September 11 but were previously ineligible for compensation from the fund.

It also covers those affected in the September 11 attack on the Pentagon and in Shanksville, Pennsylvania, where hijacked United Flight No. 93 crashed.

Thousands of firefighters, police officers, construction workers and other rescue and recovery workers spent months at the site of the World Trade Center towers that were felled by two hijacked jets.

RUBBLE SMOLDERED FOR WEEKS

The rubble and remains of the towers burned and smoldered for weeks after the attacks, exposing workers and nearby residents to an array of dangerous chemicals.

"No group suffered greater exposure to the 9/11 toxins than New York City Firefighters," said Steve Cassidy, president of the Uniformed Firefighters Association of Greater New York.

"We toiled at the site for months on end, throughout the rescue and recovery efforts," he said in a statement.

"While this inclusion of cancers will not solve the health issues of those that are sick, it is a critically important decision towards protecting their families."

Among the cancers to be covered are lung, trachea, stomach, colon, rectum, liver, bladder, kidney, thyroid and breast.

Officials overseeing the fund have struggled with the difficulty of distinguishing between people who developed cancer because of exposure to the attack sites and those who would have developed cancer regardless.

Explaining his decision, Howard said there was little definitive scientific evidence establishing a causal link between exposure to toxins after the September 11 attacks and the development of certain cancers.

He said there was only one scientific study of the health impact of exposure at the site of the attacks, published last year in The Lancet. It found an increased incidence of cancer among firefighters exposed to toxins at the World Trade Center.

Howard said his decision was largely based on the presence of known carcinogens at the sites.

The victim compensation fund was expanded by law in 2010 through the James Zadroga 9/11 Health and Compensation Act.

The list of health conditions covered by the fund has so far been largely restricted to less-serious respiratory illnesses, although it was always intended that it be reviewed periodically.

Howard said he estimated the cost of adding the cancers to the World Trade Center Health Program would be between about $2 million and $5 million for the first year.

U.S. Representatives Carolyn Maloney, Jerrold Nadler and Peter King, who sponsored the Zadroga Act, said they were "thrilled" by the recommendation and raised the possibility of expanding the fund.

"Next, we need to start working to extend the Victims Compensation Fund past its current end point in 2016 in order to ensure that responders and survivors who develop these cancers after that will be able to receive compensation," they aid in a statement.

The proposal to add the cancers will be open to public review and comment for 30 days before it becomes final.

(Reporting by Jonathan Allen, Editing By Ellen Wulfhorst and David Brunnstrom)

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