From NCPA

The past several years have seen a groundswell of regulations on plastics, particularly plastic bags and cups and food containers made from polystyrene or Styrofoam. Supporters of these bans mostly claim that such policies promote environmental protection, when in reality they carry considerable environmental tradeoffs and impose needless burdens on consumers and economic growth, says Angela Logomasini, a senior fellow at the Competitive Enterprise Institute.

• Plastic bags generate 39 percent less greenhouse gas emissions than regular paper bags and require only 6 percent of the water necessary to make paper bags.
• Simultaneously, they consume 71 percent less energy during production than paper bags and produce one-fifth the amount of solid waste.
• Similarly, reusable bags are only more environmentally friendly than plastic bags if they are used 103 times, yet on average they are used only 51 times before they are thrown away.
• A comparison of the environmental impacts of plastic cups with paper alternatives yielded similar results, with plastic causing 50 percent less solid waste by volume.

Much of the craze that has inspired frivolous and counterproductive environmental bans stems from news stories that emphasize the negative impacts of excessive pollution and littering. Specifically, numerous references are made by environmental blogs and activists to the infamous garbage "island" in the Pacific -- a giant trash heap that is "twice the size of Texas." However, researchers have debunked much of the hype regarding this "island" by showing that no such island exists. Regardless, concerns about littering should not provoke environmental bans -- they should provoke greater public support of antilittering movements, says Logomasini.

Source: Angela Logomasini, "Plastic Bag Bans Are Bad for the Environment," Competitive Enterprise Institute, November 8, 2011.