It was incorrectly reported that Dr. Donald Kennedy was sworn in as commissioner of the Food and Drug Administration on Friday. He was sworn in Thursday.

Dr. Donald Kennedy, who was sworn in today as the new commissioner of the Food and Drug Administration, couldn't have chosen a more difficult time to assume the job.

Without having participated in the FDA's controversial decision to ban the artificial sweetner saccharin, he will be expected to take part in deciding whether the ban should stand.

In an interview Kennedy, who until recently was chairman of the program in human biology at Stanford University, came down on all sides of the question surrounding the ban and other controversial matters before the FDA.

While he said "there is a need for the Delaney Amendment," he said it may need some revision. That 1958 amendment to the Food, Drug and Cosmetic Act, which was invoked to ban saccharin, says that any substance that causes cancer in animal or man when ingested must be banned. Revisions in the law are being called for across the country because the results on which the ban is based were from a study in which the animals were fed amounts of the sweetner far greater than humans consume.

Kennedy agreed that there are problems with animal testing because "we normally operate at levels way above those that occur in the environment and we are trying to figure out how this can be sensibly extrapolated" to what people consume. But at the moment, he said, "there is no real alternative to animal testing."

He said that consumers should have more to say about the regulatory process.

"Very often our interests in the welfare of consumers leads us to decide things for them without asking them," he said.

"Public policy decisions should not be made exclusively by technicians and scientists," said Kennedy, whose courses at Stanford explored the relationship between public policy and human health and environmental quality.

Kennedy is the first non-physician since 1965 to head FDA - he has a PhD in zoology - a fact that he said will not make any difference in his scientific judgments.

He has had an "overview" of the agency's mission as a member of the steering committee of the National Academy of Sciences world food and nutrition study and a senior consultant in food and nutrition to the White House Office of Science and Technology.

In this latter capacity he has been shuttling back and forth to Washington since the fall. Kennedy says it is FDA's responsibility to supply "good information" to the public through nutrition and drug education.

"In general," he said "people exercise choices to their advantage when they have the most information." FDA watchers believe Kennedy's stand on "the patient's right to know" will make him controversial.

Nutrition education would be easier, he said, if there were a "single place in the government at which nutrition policy and nutrition problems could converge and be integrated."

Some drug education can be achieved, he said, through patient package inserts in prescription medications, a proposal which FDA already has made for birth control pills. He also thinks it would be "reasonable" to require doctors to tell patients about "serious risks connected with certain drugs." And he said that this country should be do a better job of post-market surveillance of drugs.

Kennedy, who has been described by a Stanford colleague as a "superb scientist," frequently stressed the need for better scientific information on which regulatory decisions are based.

He is "very interested" in the idea of a national testing center which would conduct safety studies on drugs and food additives, funded by industry but independent of it.

"One attraction of the proposal," Kennedy said, "apart from the fact you are getting better or inherently fairer testing, is that we badly need a climate conducive to the development of better methods to establish the safety of compounds. This comes about best in strong institutions that are not fragmented."

Kennedy, a 1952 graduate of Harvard, said the agency's role between the public and industry is "obviously to protect the public," but once again, covering all the bases, he said, "it's equally obvious that the public includes some folks who happen to own stock in the pharmaceutical or food industry."

When it comes to regulatory actions with which he has had no experience, Kennedy said he hopes to make two kinds: "Some cautious decision which may prevent something from going on the market that many people want and . . . tough controversial decisions on the other side."

"I hope," he said, "to be good enough at the job to find the best middle."