McDonald's, whose disposable fast food containers have become a symbol of a throwaway society, said yesterday that it has agreed with one of the nation's leading environmental groups to study ways to reduce the amount of garbage it produces.

McDonald's Corp. and the Environmental Defense Fund agreed to a six-month joint task force to identify ways of dealing with the hundreds of millions of pounds of trash the fast food company generates each year.

The announcement comes at a time when stringent new regulations threaten to close as much as one-third of the nation's landfills, making disposal of solid wastes more difficult. Companies such as McDonald's that use disposable plastic products have come under increased criticism in recent years and have found themselves fighting off local legislation that would ban these products, which are not biodegradable.

Under the agreement, McDonald's is not bound to implement the recommendations of the task force, and the test of the effort will be in what it does with the study, the EDF and other environmentalists said yesterday.

The task force will look at possible solutions, including the redesign of packaging and shipping materials so that less would be used, and the potential for composting that could turn used french fries into potting soil.

Shelby Yastrow, McDonald's senior vice president, said that small changes have large potential, given the company's size.

For instance, he said, McDonald's redesigned a box that contains frozen french fries so that each box holds 39 pounds instead of 36. For a company that uses 1,000 tons of frozen fries a day, that change means many fewer boxes to throw away, he said.

The agreement with EDF is part of a major move by McDonald's to position itself as an environmentally and nutritionally concerned company at a time when it has been under attack for everything from its plastic foam food containers to the beef tallow in which it until recently fried its potatoes.

Fred Krupp, EDF executive director, who originally proposed the idea to McDonald's, said that the effort was worth pursuing because of the company's overwhelming presence in the fast food industry.

"We are determined to see McDonald's make fundamental changes in the way it operates," he said. "It's time to turn the golden arches green."

EDF will receive no money for its work on the task force and will be free to use tools including litigation to pursue solutions it believes in, no matter what McDonald's decides to do, said Krupp. The agreement also precludes McDonald's from using the agreement with the environmental group in marketing and advertising, he said.

Yastrow of McDonald's said that the firm's marketing studies indicate neither a loss of market share nor a potential market gain as a result of environmental issues. But he cited several examples of what he said is the company's commitment to the environment. These included the use of "more recycled paper than anyone in our industry" and promises to spend $100 million this year on products made with recycled materials to build and equip its restaurants.

While McDonald's actions have left many environmentalists skeptical, restaurant industry analysts said the company's moves reflect a genuine concern about both the environment and its corporate image.

The environmental moves are consistent with a long-term commitment to community responsibility that has included the creation of the company's Ronald McDonald houses, which provide an opportunity for the families of critically ill children to stay near the hospitals where the children are treated, said Leslie Steppel, a restaurant industry analyst with Prudential-Bache Securities Inc.

Ralph Nader saw it differently. "By concentrating on 'waste management' rather than offering to end the production of waste, McDonald's ignores the human health dangers posed by hazardous chemical emissions produced as McDonald's unneeded plastic and styrofoam packaging is manufactured," he said in a statement issued last night. "Grass-roots environmental groups are not convinced that McDonald's is serious about creating a better environment," Nader said.

"McDonald's has not been the most progressive company when it comes to the solid-waste issue in the past," said Jeanne Wirka, a solid-waste policy analyst with Environmental Action Inc., another environmental advocacy group. "This may be a change, but the real test will be in what they do with the recommendations," she said.