As recently as a week ago, McDonald's Corp. was preparing to respond to public pressure for a cleaner environment by announcing that it would extend its limited plastics-recycling program to all of its 8,500 restaurants nationwide.
But then the fast-food chain changed course, announcing yesterday that it will do away with its plastic foam "clamshell" hamburger box and switch to paper packaging.
That abrupt decision came largely as a result of an unusual alliance forged in August with the Environmental Defense Fund, people involved in the discussions said.
The change to paper, which will be phased in starting in about a month, is an indication of the way public pressure can affect a company's decisions, particularly one as concerned about its image as McDonald's.
The company had insisted that its foam packaging was environmentally sound. But "our customers just don't feel good about it," said Edward H. Rensi, the president of McDonald's U.S.A. "So we're changing."
"Customer demands are changing," said Jonathan Asher, a vice president of Gerstman & Meyers, a design firm. "In the past, convenience was the most important attribute of a package. Now there is a new need: to be sensitive to the environment."
McDonald's decision to switch to paper illustrates how a giant company can work with special interest groups. Long before the move, McDonald's established a joint task force with the Environmental Defense Fund to study how to deal with the company's solid-waste problem.
When it decided last week that it would stick with recycling, Frederic D. Krupp, the executive director of the environmental group, was able to call Mr. Rensi directly to object.
"When we learned they were planning to go to comprehensive recycling, we reacted strongly," Mr. Krupp said during a joint interview yesterday with Mr. Rensi at McDonald's headquarters in Oak Brook, Ill.
Mr. Rensi said Mr. Krupp's protest prompted a top-level management review of the company's approach to packaging.
Mr. Rensi indicated that the company had been studying the feasibility and economics of the switch, so that it already had most of the information needed to make a decision.
"We already knew we could switch to paper and save money," he said.
Mr. Krupp said the environmental group is not against recycling but felt that it was not economical to recycle foam and that the benefits of a switch in materials was greater.
"The hierarchy is reduce, reuse and recycle," he said. "The new packaging has 90 percent less bulk than the foam."
Weighing all of the factors, the company decided early this week to make the change.
The McDonald's move, Mr. Krupp said, will be a signal to industry in general to move toward more environmentally sensitive packaging. "The end of the polystyrene clamshell represents the turning of the tide on the throwaway society," he said.
R. Jerry Johnson, executive director of the Polystyrene Packaging Council, a trade association, said the total market for foam packaging such as the McDonald's box is about 1 billion pounds a year in the United States. "Our sense is that McDonald's is about 7 or 8 percent of that," he said.
McDonald's officials said the new packaging will include a cellophane-like outer wrapper.
The first package to be phased out will be the foam hamburger box, which Mr. Rensi said accounts for 75 percent of the total foam the company uses.