Neill Heath, once head of press and advertising for the World Wildlife Fund, has become the head of press and public information for the National Gallery of Art. Heath replaces Katherine Warwick, who had been at the gallery for 15 years before she left in June to become director of the Hillstead Museum in Farmington, Conn. Heath is arriving in time to work on the Treasure House exhibition and next month's royal visit of Prince Charles and Princess Diana. Heath is a Washingtonian who once worked for Hill & Knowlton and J. Walter Thompson . . .

Russell E. Train, former head of the Environmental Protection Agency and president of the World Wildlife Fund, has taken on a major new environmental position. He becomes chairman of the new World Wildlife Fund created by yesterday's merger of the World Wildlife Fund and Conservation Foundation. The World Wildlife Fund will be the name of both organizations now . . .

"The Gods Must Be Crazy," the poignant story of a primitive African bushman entangled in the 20th century, has become the greatest foreign movie box-office success in the history of American theaters. The South African film, written, produced and directed by Jamie Uys, has grossed $22 million and is still playing in selected theaters around the country. Its earnings topped, by $6 million, "La Cage aux Folles," the French movie that had previously held the record . . .

Authors Iris Murdoch, Doris Lessing and Jan Morris were named as candidates for Britain's most valuable literary award, the $20,850 Booker Prize. The new books that earned the nominations: Murdoch's "The Good Apprentice," Lessing's "The Good Terrorist" and Morris' "Last Letters From Hav." Murdoch's novel, "The Sea, The Sea," won the prize in 1978 . . .

Celebrity artist Andy Warhol was enjoying himself thoroughly Sunday at Manhattan, inc.'s first anniversary party in New York. He would approach people with an atomizer of Este'e Lauder's new perfume, "Beautiful," and spray it into the air. "It's so wonderful, I carry it everywhere with me," he said as he sprayed the scent on himself. "It's all in the name, you know. People can say you smell beautiful." Then after a professional's pause, he added, "I was thinking it might be fun to start my own perfume line and call it 'Stink.' "