WASHINGTON – The federal government may be unprepared for future environmental disasters on the scale of the September 11, 2001, terrorist attacks, according to a new report that criticizes the Bush administration’s latest effort to decontaminate apartments near the World Trade Center.

In a study released today, the Government Accountability Office concludes that unless federal agencies develop better plans for handling environmental crises, “the nation may face the same challenges after future disasters” as it did when the collapse of the Twin Towers blanketed the streets and buildings of Lower Manhattan with toxic dust and debris nearly six years ago.

Studies over the past year have begun to show links between the toxins released during the collapse and respiratory illnesses suffered by people who worked and lived in the area, particularly the rescue workers who toiled for weeks at ground zero.

The GAO report examines a program that the federal Environmental Protection Agency began in January to test and clean living spaces near ground zero following concerns that its initial decontamination attempts were inadequate.

Senator Clinton and two New York lawmakers seized on the findings today to escalate their long-running criticism of the Bush administration’s response to the attacks. At a Capitol Hill press conference this afternoon to release the report, Mrs. Clinton said the study “confirms our worst fears about the Bush administration’s incompetence and indifference.”

The Democratic presidential front-runner has assumed a leading role on issues related to the September 11 attacks, in anticipation of a possible general election battle with Mayor Giuliani, whose widely-hailed performance in the immediate aftermath of the disaster helped vault him to the lead in the Republican primary race.

Mr. Giuliani has also drawn criticism from some corners for the city’s response to the attacks. Asked today whether the city, and the former mayor in particular, bore any responsibility for the environmental and health problems, Mrs. Clinton said she was focused on the federal response, but she allowed that there were “problems at all levels of government.” She also referenced a public hearing in February 2002, during which she said city officials “readily admitted they were ill-prepared.”