A move is underway in Congress to stop the federal Office of Consumer Affairs from continuing one of its major activities of the past year. The effort comes as some consumer group leaders praised the work of the White House unit, citing it as one reason they support President Carter's reelection.

The Senate may vote as early as today on a proposal by Sen. John Danforth (R-Mo.) that would bar the OCA from formally intervening in regulatory proceedings in the future.

Danforth says that the OCA, which has been a formal party to five significant procedings before the Federal Communications Commission and the Federal Energy Regulatory Commission, has no statutory authority to take on such matters.

By formally becoming a party to a dispute before a regulatory agency, OCA can act on behalf of all consumers to protest proposals by industry and submit evidence that will be considered in the decision-making process. Generally, consumers have not been represented in cases before regulatory agencies, although the agencies are supposed the act in the public interest.

Calling the OCA interventions "an affront to Congress," Danforth has asked other Senate members in a "Dear Colleague" letter to support his amendment to the Department of Housing and Urban Development-Independent Agencies appropriations bill that specifically would bar the agency from Intervening.

Another Danforth amendment to the same funding bill would affect two regulatory agencies -- the Environmental Protection Agency and the Consumer Product Safety Commission. It would bar the two agencies from their current practice of offering funds to aid outside groups intervening in EPA and CPSC proceedings.

Esther Peterson, director of the consumer office and the special assistant to the president of consumer affairs, wrote last Friday to Sen. Warren Magnuson (D-Wash.), chairman of the Appropriations Committee, urging the Senate to defeat the proposals.

"Adjudicatory proceedings of this sort can dramatically affect the rates that consumers pay for telephone service, energy, and other utilities," Peterson wrote. "I believe our effects have had, and will continue to have, substantial benefit for consumers."

The Danforth proposal caught White House officials by surprise. Peterson apparently had not been told of Danforth's intentions until last Thursday, even though the issue could have come to the Senate floor the next day, and Edward Cohen, the general counsel in Peterson's office, went to Capitol Hill Friday in an effort to Capitol Hill Friday in an effort to make the OCA's case. It is unclear, however, whether Danforth's prosposal has the support of other Senate members.

Peterson's office has intervened in several controversial regulatory matters. Perhaps the most signifcant is the potentially multibillion-dollar case before the FCC on the question of whether American Telephone & Telegraph Co. should be given a higher rate of return.

The Office of Consumer Affairs has asked for $118,069, including $30,000 for experts in these interventions, in its fiscal 1981 budget request, Danforth pointed out in his letter.

Danforth also linked his view on the OCA matter to House action in 1978 that killed a proposal to set up a Consumer Protection Agency, a government body that would have been charged primarily with participating in such proceedings.

Noting Peterson's "zeal to represent consumer interests," Danforth said, "her efforts to use her office to that end are without statutory authorization" and "a repudiation of the vote [on the Consumer Protection Agency] in the House."

In fact, in a June 19 funding report for a similar approriations Committee said that "the committee has noticed a change in direction of the Office of Consumer Affairs."

"The office is undertaking certain activities that would have been authorized by a consumer representation bill," the report said. "The OCA is cautioned to limit its activities to those authorized by statute."