To become law, the ban would require approval by the City Council. The Council speaker, Christine C. Quinn, suggested in an interview that she was open to a ban on plastic foam as part of a larger effort to increase recycling.

“It lives forever,” Ms. Quinn said. “It’s worse than cockroaches.”

The plastic foam used in food packaging is not actually Styrofoam, according to Dow Chemical, the company that makes Styrofoam. The company says its product is widely used as insulation, but not “in the manufacture of disposable foam products, such as cups, coolers, meat trays and packing peanuts.”

Officials at City Hall said a plastic-foam ban could save millions of dollars a year. Plastic foam, which is not biodegradable, can add up to $20 per ton in recycling costs when the city processes recyclable materials. The city handles about 1.2 million tons of food waste each year; the mayor’s office estimated that the city’s annual waste stream included about 20,000 tons of plastic foam.