Which Bag Is Better? Paper Or Plastic

You’re checking out of the grocery store and, as usual, the bagger asks, “Paper or plastic?”

You want to do the right thing for the environment. But what is it? What it is, unfortunately, is complicated.

A grocery bag’s effect on the environment is multifaceted. A bag consumes natural resources - petroleum and natural gas in the case of plastic, and trees in the case of paper. The manufacturing process generates pollution, as does incineration of used bags. And if buried, of course, bags consume landfill space.

In a study published in 1990, Franklin Associates Ltd., a solid-waste and environmental consulting firm in suburban Prairie Village, Kan., tabulated most of the environmental costs associated with the two dominant grocery sacks: unbleached kraft paper and polyethylene bags.

First, the study found that fewer groceries on average are packed into plastic bags than in paper bags. From 1.5 to 2 plastic bags are used for every paper bag.

Nonetheless, Franklin Associates concluded that by most measures, plastic bags exacted a smaller environmental price. Compared with paper, their manufacture creates less air and water pollution and less solid waste in landfills. When incinerated, polyethylene bags produce more heat and less ash than paper, both points in their favor.

And as a larger proportion of bags are recycled and reprocessed into other products, polyethylene bags gain an even bigger edge over paper bags in energy savings, according to the study.

Paper bags gain points if they’re made with recycled content.

And consider your habits. If you will reuse a bag, that’s reason to choose it, according to Bill Franklin, chairman of Franklin Associates. He routinely takes his sacks back to the store with him, although he noted that his wife usually forgets. Even so, he said, “If you reuse that bag just once, the consequences (of manufacturing and disposal) are cut in half.”