The D.C. City Council is preparing to pass a bill that calls upon city agencies to shun purchases from companies in North Carolina until the state frees all members of the Wilmington 10.

The legal effect of such a measure in the future is uncertain. The D.C. government currently has $283,000 in contracts with North Carolina firms, including $114,000 for tobacco products it buys to resell to inmates in D.C. prisons.

Of the Wilmington 10, nine are young blacks in prison for firebombing an empty grocery store following racial disorder in that coastal city in 1971.

Earlier this year, Gov. James B. Hunt Jr. shortened their sentences but refused to pardon them. The 10th member of the group, a white woman, was paroled last year.

The Wilmington 10 case has attracted national and international attention, with the defendants widely portrayed as the victims of Southern racism - a view disputed by Gov. Hunt, among others.

The proposed D.C. council measure says the Wilmington 10 "continue to be the victims of injustice at the hands of North Carolina authorities and have become well-known symbols of oppression . . ."

It calls upon the city agencies "to refrain from the award of any contract or business" to any firm or person located in North Carolina.

The Wilmington 10 provisions were attached by the council to another bill that requires city employes to boycott any meetings or conventions held in the 15 states - including North Carolina - that have failed to ratify the Equal Rights Amendment to the Constitution.

The ERA boycott already is in effect under terms of earlier emergency legislation and an executive order issued by Mayor Walter E. Washington.

The pending measure, sponsored by council members Marion Barry (D-At Large) and Hilda Mason (Statehood-At Large), reflects the activist mood of the mostly black council, which has adopted numerous resolutions supporting civil rights causes. The boycott measure was advanced procedurally at a council legislative review meeting yesterday, and will be on the agenda for preliminary approval next Tuesday.

The boycott measure is not a resolution, which would have only symbolic effect, but a bill, which would have at least the limited force of law. It also would be subject to review and a possible veto by Congress.

Gov. Hunt, tld of the council proposal, said in Raleigh, N.C., that "it is unfortunate that (the council members) have such a limited understanding of the case, and it is unfortunate that they picked such an inappropriate way to express their concern."

Rep. Stephen L. Neal (D-N.C.), whose district includes the tobacco company with the D.C. contract, said the proposal is "just ridiculous . . . I am not arguing the merits of the (Wilmington 10) case, but I just don't see that that kind of action would have any beneficial effect, period."