The Planet Money article also cites a 2011 study by the UK government that found a person would have to reuse a cotton tote bag 131 times before it was better for the environment than using a plastic grocery bag once. When you factor in the manufacturing process used to make cotton bags, the impact on the climate is even worse than plastic.
Cotton, if grown in the United States, requires planting with heavy equipment, which uses fuel; weed killer; and the use of an exfoliant to remove cotton leaves before the cotton balls can be harvested using more large machines fueled by diesel or gasoline. Then there’s the process of actually manufacturing the cotton items. The Danish government estimates that “these factors make cloth bags even worse than plastic,” said the Planet Money article. “They estimate you would have to use an organic cotton bag 20,000 times more than a plastic grocery bag to make using it better for the environment.”
The Danish government study concluded that the best reusable bags “are ones made from polyester or plastic like polypropylene” but cautions that “those still have to be used dozens and dozens of times to be greener than a plastic grocery bag, which has the smallest carbon footprint for a single use.”
Plastic is fantastic in many ways. The next time you go to the grocery store, tell the store manager that you want the eco-friendly plastic carryout bags.