The executive director of the American-Arab Anti-Discrimination Committee, who was among Arab-Americans who met with President Reagan last week, has charged that the White House distributed "Israeli propaganda" in a document about the Palestine Liberation Organization in Central America.

Omar Kader said in a written statement that the group was "shocked" when it saw the document, a July 20, 1983, edition of the "White House Digest" saying the PLO "is an active ally of communist revolutionaries throughout Central America."

Kader said the document was part of the "official White House packet" given the group.

Kader also criticized the White House for a photo session with Reagan as a "pat on the head" for Arab Americans. Kader said that group members thought "we were being asked to attend a serious discussion" with the president, but that Reagan "had no intention of discussing the Middle East and said so."

Kader also charged that Assistant Secretary of State Richard W. Murphy, who spoke to about 150 U.S. Arab-American leaders, "appeared oblivious to any cases of mistreatment of Arabs in Israel." He said Murphy was "challenged" at the meeting by Mike Hazem Monsour of New Mexico, who said he was tortured for 21 days last year by Israeli police while visiting his mother on the West Bank.

George Salem, a Washington attorney and former executive director of ethnic voters for Reagan-Bush, said that the document to which Kader referred had been left behind from an earlier briefing on Central America to a different group and was not included in the packet for the Arab Americans. He said White House officials apologized and agreed to talk about the document. Reagan said in a speech Jan. 24 that a "new danger" in Central America "is the support being given the Sandinistas" by the . . . Palestine Liberation Organization."

Referring to the session with Reagan, Salem said, "no one was disappointed, except perhaps" Kader. The meeting Friday was part of the founding session of the Arab American Institute, which seeks to increase participation of Arab Americans in national and local U.S. elections.