The company had previously promised to use only environmentally friendly packaging by 2020.
mcdonalds cups styrofoam make a comeback
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As long as your cold drink is ice-cold, you may not care what cup it comes in. But whether you're carrying a paper or plastic cup can have serious environmental impacts, and that's one reason Chicago-area residents—and the company's shareholders—weren't thrilled to see that McDonald's is back to serving its cold beverages in Styrofoam cups.

It's unclear how many McDonald's in the Windy City are back to using polystyrene cups that don't biodegrade and were supposedly being phased out across the company as the burger chain attempts to become more eco-friendly. In fact, McDonald's has promised to use only certified or recycled packaging by 2020. In 2013, McDonald's stopped using Styrofoam cups to serve its hot beverages, and in recent years, the company has only used Styrofoam cups for its iced tea—as opposed to all its cold beverages. (Both Dunkin' Donuts and Chick-fil-A also use Styrofoam cups.)

But in some locations in Chicago, all large, cold beverages are coming with Styrofoam cups, and a company spokeswoman declined to say why—or whether we can expect to see more of them at additional locations across the country. Instead, spokeswoman Becca Hary told The Chicago Tribune only that, "this summer, Chicago-area restaurants may be using a large Styrofoam cup to serve their customers select cold beverages. We continue to work with our suppliers on sustainable packaging options that reduce our sourcing footprint." But with the chain's summer promotion of selling every soft drink for 99 cents, they'll likely be selling a lot of the large beverages.

Polystyrene is a popular material used across the restaurant industry because, not only does it keep cold beverages cooler (or warmer) for longer, it's an inexpensive option that doesn't "sweat" like so many other beverage containers often do. But the material's very large, eco-unfriendly-footprint is cause for serious concern. And in May, 32 percent of McDonald's shareholders voted to force the chain to assess the environmental impact of its Styrofoam cups, a sign they're not pleased that McDonald's continues to use a product that so greatly impacts the environment.

Other companies—including 15 who recently endorsed a U.K. report that recommended replacing polystyrene cups with other, more eco-friendly options—are moving away from using Styrofoam cups, making it even more surprising McDonald's would expand its use of these cups in Chicago, or anywhere for that matter.