Four Fairfax County supervisors who have pledged not to accept campaign contributions from real estate developers said yesterday they will return $10,000 to a political action committee after learning that the bulk of the money had come from a developer.

One of the incumbents, Vice Chairman Martha V. Pennino (D-Centreville), said she felt "compromised and betrayed" by the contribution. She returned $3,500 yesterday to the county's Chamber of Commerce, which organized the PAC. Supervisor Nancy K. Falck (R-Dranesville), who received $1,500 from the PAC, said: "The money will certainly be returned."

A spokeswoman for Republican Chairman John F. Herrity also announced that his campaign had decided to return his $3,500 to the chamber. "It certainly puts our campaign on the defensive and it's not something we need," she said.

Six candidates for the county board, who are up for election on Tuesday, received money from the PAC, according to campaign finance forms filed with the state electoral board. Spokesmen for five of the six -- one could not be reached -- said they were not aware when they accepted the money that the principal source of the chamber's PAC funds was Bahman Batmanghelidj, a developer who is planning a huge mixed-use project on 211 acres near Dulles International Airport. Batmanghelidj gave $10,000 of the PAC's $17,400. Other developers with pending applications also contributed to the PAC.

Supervisor T. Farrell Egge (R-Mount Vernon), who received $1,500, did not return phone calls from a reporter yesterday. A spokesman for the Republican candidate for the Annandale District seat, D. Patrick Mullins, said he had no policy limiting developers from donating to his campaign.

Supervisor Elaine N. McConnell (R-Springfield), who received $1,500 from the PAC, at first said she felt "badly" about the source but would not make a decision on returning it until she had met with her staff. A half-hour later, she said "we probably are going to give our money back."

A trustee of the chamber's PAC, Philip M. Reilly, said the PAC had accepted money from all sources with no strings attached. The PAC, which has a bipartisan board of trustees, asked "candidates . . . if they were not going to accept money from a PAC and nobody came back and said we won't," he said.

In another campaign finance matter, Herrity's campaign said that a major hotelier who plans to build a large hotel in the Dulles Access Road corridor is free to donate money to Herrity because he is not a developer. The hotelier, Daniel M. Ross, who is also a lawyer, gave Herrity $10,000 last week, the largest contribution from an individual to the campaign.

Ross is the principal owner and manager of the Sheraton Premiere at Tysons Corner and the Sheraton International Conference Center in Reston. He said in an interview that he plans an expansion but does not expect those applications to come before the county board for at least two years.

In a separate matter, Herrity's spokeswoman, M. Constance Bedell, said that a total of $2,000 in donations from two other developers with land-use applications had slipped through the screening process at Herrity's headquarters and will be returned. "We have 3,500 contributors and we have three or four volunteers who struggle through this and maybe they miss a few," she said. "We're doing the best we can."

Bedell said Herrity's campaign already has returned at least $16,000 in contributions from developers.

One of those who contributed to Herrity's campaign, Jacques J. Moore, is the owner of Moore Cadillac Co., a Tysons Corner auto dealership. Moore is a limited partner in High Ridge Associates, a development concern that came before the county board with a land-use matter Oct. 19.

The board voted 5 to 0 to approve the application, with Herrity and three other supervisors out of the room. Bedell said that Herrity had not left the room intentionally to avoid disclosing the contribution from Moore. She said he probably had stepped out of the meeting to visit the men's room.

Herrity said last year that he had walked out of the county board's public meetings in some land-use cases over the years instead of disclosing his ties to the developers involved. He said it was common practice on the board to do so -- a statement that several other supervisors disputed.

State law requires that supervisors disclose their contributions from developers and others involved in land-use cases before voting on those cases.