A consumer coalition petitioned the Agriculture Department yesterday to ban the use of sodium nitrite and nitrates in all processed meat.

"The use of nitrates and nitrates in meat and meat food products poses extreme health hazards" because they can combined with other substances to cause cancer, the petition said.

The coalition was led by the Community Nutrition Institute and was joined in its petition by Rep. Fred Richmond (D-N.Y.). Other petitioners included the Consumer Federation of America. National Consumers League, Consumers Affairs Committee of Americans for Democratic Action, and the Virginia Citizens Consumer Council.

Last month, the Agriculture Department gave the food industry until Jan. 16 to prove that the use of nitrates - and nitrates from which they are derived - to not produce cancer-causing nitrosamines during ordinary processing or kitchen preparation of bacon.

Similar information will be required over the next two years for other processed meats, including cooked sausages and canned products, in an effort by the department to gain more information. If the proof is not provided, the department says, it might prohibit the use of nitrites in some or all cured meat products.

Nitrates and nitrites have been used for centuries in the form of saltpeter, for example, to preserve meat. Modern use has been directed to the prevention of deadly botulism bacteria, to provide color to red meat and to aid in curing.

Richard E. Lyng, president of the industry-supported American Meat Institute, said the consumer petition was based on "absolutely no evidence" that the amounts of nitrite used in meat processing are harmful. "To even suggest that sodium nitrite be banned is ridiculous," Lyng said in a statement.