Like other federal workers facing furloughs, researchers at the Food and Drug Administration are fretting over how they'll pay mortgages and buy Christmas presents. As scientists, however, they have an extra fear: that years of research on food-borne disease may be jeopardized.

And, although they offered, the researchers wouldn't be allowed to come in on their own time to maintain cell cultures and work on animal studies.

"We're being banished from the building," said researcher Kristina Williams, who said that projects she has been working on for four years could be rendered useless unless she can tend to them.

The frustration that Williams and her colleagues at the downtown facility have been feeling at the FDA is shared by millions of federal workers across the country. Besides threatening stability at home, the furloughs have the potential to wreak havoc on the job.

A spokesman for the FDA, whose furlough plans call for closing on Thursdays and Fridays, said workers were being kept out of the building because of a statute cited by the Office of Personnel Management.

Mary Ann Maloney, a spokeswoman for the personnel agency, said there were two reasons for the practice.

If an employee on the premises during a furlough were to be injured, that person would not be covered by workers' compensation, she said. Also, if a supervisor was aware the employee had been working, the government could be compelled to pay the employee under the Fair Labor Standards Act.

"That would defeat the whole purpose of Gramm-Rudman," Maloney said.

Although the FDA researchers have been told not to come to work on furlough days, employees in other government offices said they have not been discouraged by supervisors from coming in. Many political appointees who may be fuloughed have said they believe they are expected to come in.

The scientists say they are worried not about money, but about their work.

"I only know that FDA management is threatening my research, which is my whole life," said Barbara A. McCardell, acting branch chief for the agency's research arm.

"They're playing a game of chicken and we have to suffer," said researcher Stayce Keasler.

Officials at FDA could not say how strictly they would enforce the no-volunteer-work policy for the 19 people McCardell supervises and for the nearly 800 other researchers at the agency. But McCardell did remember that during the brief 1981 furlough a colleague was "escorted out of the building."

McCardell and her colleagues are conducting basic research on food- and water-borne diseases such as salmonella, work that requires extensive culturing of antibodies and maintaining cell lines. They often come in on weekends, she said.

"You have to take it out and feed it every other day," McCardell said. "We've been maintaining this one particular culture for years. It would be hard to replace."

But FDA officials have told workers they must be out of the building from Wednesday afternoon until Monday morning if a long-term furlough plan is set in motion.

McCardell said the furlough policy would also severely affect the lab's ability to respond to emergencies, such as outbreaks of suspected food poisoning.

FDA spokesman Jeff Nesbit said the agency is drawing up emergency plans so that it would be able to handle such situations. The agency's plans if furloughs go into effect call for lab animals to be cared for by medical core personnel exempt from the furlough, but the researchers fear they would mishandle the animals and jeopardize the validity of studies.

The scientists' worry about their research is just part of their deeper, long-term frustration with working for the federal government, subject as it is to political tremors and budgetary battles.

"You feel like saying you just want to get out of government work," Williams said. "You lose your motivation; it's very depressing."

All this is not to say that the prospect of doing without two-fifths of her pay before Christmas is not devastating to a worker such as researcher Joan Jappa.

"I live from paycheck to paycheck," said Jappa, a single mother who is supporting her 10-year-old daughter and her mother on a $32,000 annual salary.

The District resident said she has virtually nothing left over after paying basic expenses such as her mortgage, utilities, food bills and tuition at Howard University, where she is pursuing a doctoral degree in genetics.

"The first possible furlough would take $400 out of my take-home pay. I just can't afford to lose that," Jappa said.

For Keasler, a recent college graduate who just began working at the FDA this year, the furlough has been a rude awakening.

"I uprooted my husband. We just came from Alabama. We're just starting out; they told me I was going to make a certain amount, and I counted on it. We wanted to buy a house. I wanted to go back to school," she said. "If this is going to happen every year, how can they get the best people? How can they treat people like this?"