Two consumer groups accused the Reagan administration yesterday of not protecting the public from an array of potentially hazardous chemicals added to the nation's food.

"The federal government has not done what it should to protect the public from controllable risks in the food supply, and the Reagan administration has only increased these risks further," said Ellen Haas, head of a new consumer group, Public Voice for Food and Health Policy. "We need to strengthen government protection, not weaken it."

At a separate news conference at the Capitol, the Center for Science in the Public Interest focused on problems in the regulation of food additives, particularly sodium bisulfite, a preservative commonly used to make salads and other foods appear fresh.

Michael Jacobson accused the Food and Drug Administration of "incompetence and lethargy" in handling sodium bisulfite and related chemicals. The agency proposed last summer that those chemicals continue to be "generally recognized as safe." Jacobson's group asked the FDA last fall "to ban or severely restrict" their use.

Yesterday Jacobson announced that sodium bisulfite has since been linked to the death of an Arizona man with asthma who reportedly ate lettuce treated with the chemical in a restaurant. He released a letter from an allergy researcher, Dr. Ronald Simon of the Scripps Clinic and Research Foundation, concluding that the death "was the result of a sulfite sensitive reaction."

Simon and others have documented a range of allergic reactions to sodium bisulfite, according to Jacobson, who said Simon has estimated that one in 20 asthmatics--as many as 500,000 Americans--may be sensitive to such chemicals.

Sulfiting agents are used to prevent discoloration or bacterial growth in potatoes, lettuce and sauces at restaurants, in fish, in wine and some beers, in dried fruits, in numerous packaged foods and in many drugs, according to the consumer group.

The FDA recently recommended to state health officials that restaurants post announcements that sulfites are used. Jacobson called this "totally inadequate," and said "we are extremely concerned that FDA is also reluctant to take action on other hazardous food additives."

The Public Voice consumer group listed 10 food-hazard problems, seven at the FDA and the rest at the U.S. Department of Agriculture, the Environmental Protection Agency and the National Marine Fisheries Service.

It said that these included lack of safety inspection of two-thirds of all fish consumed, pesticide residues on fresh produce, chemical residues in meat and poultry, excessive exposure to a natural cancer-causing agent called aflatoxin, relaxation of additive policy, delays in reviewing food color additives, and lead in food cans.

FDA spokesman William Grigg said that in general "our tests of the food supply show no areas in which pollutants have reached a danger level for anyone eating a balanced diet." He added that many of the changes requested by Public Voice require congressional action.

Grigg said that the agency has not decided what to do about sodium bisulfite chemicals, and he credited Jacobson's group with calling the problem to the government's attention. "What we hope to do is to reduce sulfites when use is not necessary and label it when it is," he said.