Paper or plastic?

Forrest M. Mims III

Is the environment better off if we sip water from a paper or a plastic cup?

Plastic cups are made from petroleum and natural gas. They do not break down in landfills. Paper cups cost more, but they are manufactured from wood, a renewable resource. Thus, we should use paper cups. Right?

Fifteen years ago Canadian scientist Martin Hocking analyzed this issue in a paper published in the journal Science and concluded, “The paper cup consumes 12 times as much steam, 36 times as much electricity, and twice as much cooling water as the plastic cup.”

Hocking also found that producing a paper cup produces about 580 times the volume of waste water required to produce a plastic cup. Making a paper cup also causes considerably more air and water pollution than making a plastic cup.

Hocking’s study stimulated a flurry of responses from environmentalists who had been condemning the use of plastic packaging. Shortly before Hocking’s study appeared, they had persuaded McDonald’s to wrap hamburgers in paper instead of selling them in plastic clamshell containers.

Hocking’s numbers have been refined, but his basic conclusion that a plastic cup is more environmentally friendly than a paper cup still stands.

Studies similar to Hocking’s have given similar results for plastic versus paper bags. Studies have shown that plastic bags consume much less landfill space, they are cheaper to make and they produce far less air pollution than paper. They are also easily reused and they can be recycled.

There is no free lunch, and the plastic versus paper controversy is no exception. Plastic requires petroleum, and you know where most of that originates. Shouldn’t we be reducing our use of petroleum wherever possible?

Again, the answer is not so simple. For while plastic is made from oil, the energy required to produce paper far exceeds that required by plastic.

The "Paper or plastic?" question demonstrates that environmental questions are often much more complicated than they might at first appear.

There is plenty of middle ground between radical environmentalists and energy wasting businesses, governments and consumers. Perhaps both sides would do well to carefully reassess their positions. Responsible environmental stewardship can save money and reduce oil imports.

Forrest M. Mims III and his science are featured online at www.forrestmims.org.

This feature was originally published in Forrest Mims's weekly science column in the Seguin Gazette-Enterprise, Seguin, Texas. The column is written for a general audience.