New York ? Respiratory ailments, mental trauma and other problems that arose after the Sept. 11, 2001, attacks are costing the U.S. health care system $393 million per year, according to an analysis released Tuesday.

The estimate was part of a report by a panel that Mayor Michael Bloomberg convened last year to study 9/11 health effects and treatment programs, which are said to be running out of funding 5 1/2 years after the attacks.

Some of the people who worked amid the dust, smoke and ash at the site have died. Others have developed conditions including respiratory problems, anxiety, depression and post-traumatic stress disorder.

The panel noted the liability fight as another mounting expense. At least 6,000 federal lawsuits have been filed by emergency workers.