When federal officials told students at Stuyvesant High School to return to school less than a month after the September 11, 2001, terrorist attacks, they said the school — located blocks from ground zero in TriBeCa — was safe. Nearly five years later, alumni of the prestigious public school say they were sent back too soon.

Dozens of the graduates returned to Stuyvesant yesterday, this time to stand with local politicians who are calling for increased federal funding for medical studies and health aid aimed at the thousands of people who may have developed illnesses related to the September 11 attacks.

“The federal government lied,” Rep. Jerrold Nadler, who represents Lower Manhattan, said. “They judged getting the economy moving a little more quickly was more important than the health of thousands of workers and children.”

Amid increasing reports of respiratory illnesses sustained by Lower Manhattan workers and residents, the Environmental Protection Agency has come under fire for the public statements it issued after September 11 claiming the air was safe to breathe in the blocks around the World Trade Center site. Workers, students, and residents have sued the agency and its director at the time, Christine Todd Whitman.

The government has defended Ms. Whitman’s actions, citing the need to reassure the public in the wake of the disaster.

At least one former Stuyvesant student, Amit Friedlander, has developed Hodgkin’s disease, a type of cancer, since September 11. An honors student at the school renowned for its science program, he researched the literature on his condition after he was diagnosed and discovered “exposure to toxic pollutants”is a major risk factor for the disease.

“You could smell smoke both inside and outside the building for months,” another Stuyvesant graduate who is leading the student response, Lila Nordstrom, said. Ms. Nordstrom is attempting to organize all of her old high school classmates to determine the extent of the health problems, but she said it has been difficult because the college-bound students have scattered across the country. Among the graduates Ms. Nordstrom has been in touch with, “there are a lot of respiratory problems,” she said, adding that her own asthma has gotten worse.

The Board of Education spent $1 million to rehabilitate Stuyvesant in the weeks following September 11. During the 2001-02 academic year, however, toxic waste was transported by trucks up West Street past the school from ground zero 24 hours a day. Cranes would then transfer the material to barges anchored in the Hudson River on the north side of the school. “Every time the crane took up a load of debris, they would drop it in the barge and a huge dust cloud would be kicked up,” Ms. Nordstrom said.

Mr. Nadler yesterday called for a special prosecutor to investigate Ms. Whitman and for a $2 billion federal grant to treat September 11-related illnesses through the Medicare program. The president of Manhattan, Scott Stringer, also appeared at Stuyvesant yesterday. He is pushing for a $16 million federal reimbursement for a September 11-related illness screening program established at the Bellevue Hospital Center by Mayor Bloomberg.