Editor’s note: Art Woolf is an associate professor of economics at the University of Vermont. He served for three years as state economist for Gov. Madeleine Kunin beginning in 1988.

The Vermont Senate recently passed, by a vote of 30-0, a bill (S.113) that bans the free plastic bags that are currently used by just about every grocery store in Vermont. The bill is likely to pass the House as well. Plastic bags have come under increasing scrutiny over the past few years, ever since a large mass of floating debris, much of it plastic, was discovered in the middle of the Pacific Ocean.

Banning plastic bags in Vermont, or anywhere in the U.S., won’t do much to solve that problem since most of the plastic comes from Asia. Banning plastic bags in Vermont will, according to advocates, reduce roadside litter, prevent bits of plastic from contaminating soil and water supplies, and reduce the amount of plastic waste going into landfills.

Those are all likely outcomes. However, it’s worthwhile to consider some other consequences of banning the flimsy plastic bags we are all accustomed to using when we shop. First, those cheap plastic bags, which cost about a penny, will not be banned. They just won’t be free. Shoppers will have to pay 10 cents for a bag. Advocates argue that will encourage people to bring their own bags to the store, and that will probably happen.

But some people won’t bring their own bags. They may forget them or just pay the 10-cent charge because it’s more convenient than bringing bags into the store. Since the bags are more costly to shoppers, storeowners are likely to provide customers with a higher quality, sturdier, plastic bag; one that costs the store less than a dime, but more than a penny. As long as customers are paying for something, stores might as well give them something of more value and will reuse them.

The 10-cent charge may encourage other stores to provide more expensive paper bags to their customers. To most supporters of the plastic bag ban, the best solution would be for people to use cloth bags, which many people already do.

But all of those alternatives — thicker plastic bags, paper bags and cloth bags — have environmental problems of their own, and the Danish and English equivalents of our Environmental Protection Agency have analyzed their environmental footprints by calculating how many times these alternative bags would have to be used to have the same environmental impact as disposable plastic bags.

The English study, which focused only on the carbon impact of different bags, found that paper bags would have to be reused at least three times to have the same impact on global warming as a disposable plastic bag. Sturdier plastic bags would have to be used at least four times, and cotton bags more than 100 times. That’s two years, assuming someone goes to the grocery store once a week.