IAN LEVENTHAL, papier mache sculptor, has had his work exhibited at such spots as the Art Gallery of Ontario, the nearby Art Gallery of Hamilton and the Tokyo An Gallery. Born in Toronto, he received a Bachelor of Arts degree from York University. He's had sellout one-man shows at the Gallery Danielli and is now represented by Maurice Fisher of the Salon des Artistes. Creeds recently bought an entire 50-piece Leventhal collection for its store and Holt Ren- frew showed eight enormous sculptures as part of its window displays. Some of his work Is In New! York in Tiffany's Fifth Avenue windows until Aug. 21. The theme is the Four Elements, but, as put by Mr. Leventhal: "Unfortunately, there are five windows, so the fifth one is dedicated to the Unknown Element. The window Air is represented by a lady on a pink swan; Earth by a lady in a bowl of fruit on the back of an elephant; Fire by two steamy dancers consumed by orange flames; Water, a Venus emerging from her shell; and Unknown by a futuristic figure on a charging horse." Concurrently, 19 of his latest works are on view in Chicago in the Merrill Chase Gallery; and another shipment is enroute to Los Angeles for an opening on Aug. 19 in the Galerie Michael. ; Mr. Leventhal, 28, owns a graphic design busi- ness and has just signed a contract with a U. S. publisher to produce limited-edition prints of his work. He is married to Renee Beranbaum and they have one daughter, Elyssa, 6 months old. Her father told me: "She's my best creation to date. and that's the truth."