Q: Paper or plastic: Which supermarket choice is better for the environment?

A: Tuncer Edil, a professor of civil and environmental engineering at UW-Madison, came back with a surprise answer: C, "Neither of the above."

"Both are bad," Edil said, "but plastic wins the number- crunching in life-cycle analysis."

When applied to this question, the life-cycle analysis technique measures each bag's need for energy, material and landfill space.

Some other variables that do not enter life-cycle analysis are also important, Edil said.

"Plastic bags are a menace to wildlife and do not decompose for a long time if they escape into the environment."

Paper bags are easier to break but also to recycle.

"The best advice is to bring your own bag, box or day pack, to the store," Edil said. "In the old days, people used cloth bags or net bags to carry their groceries. But don't forget, you can reuse a 'single use' bag two or three times."

So here's a better question: "Throwaway bag or reusable?"

- Produced in cooperation with University Communications

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