Plastic Bag Fears Based on Misquoted Study

Published May 1, 2008

Shoppers the world over can breathe a collective sigh of relief now that leading scientists are stepping forward and defending the widespread use of plastic bags at supermarkets and other retail outlets.

Misquoted Study Fuels Fears

In recent years, polyethylene bags, usually made from petroleum or natural gas, have largely displaced the more cumbersome paper sack as a means of carrying items from the store to the home or office. But their ubiquitous presence has drawn the ire of environmental activists and politicians who claim the bags inflict significant harm on the environment, including causing the death of 100,000 mammals and one million seabirds annually.

The plastic bag scare, it turns out, is based on a 1987 Canadian study that investigated the harm to marine mammals and seabirds from discarded fish nets. For reasons not fully understood, Australian researchers, in a follow-up study conducted 15 years later, mistakenly attributed the death of 100,000 marine animals to plastic bags instead of the “plastic litter” cited in the Canadian research.

“Plastic bags do not figure in entanglement. The main culprits are fishing gear, ropes, lines, and strapping bands,” David W. Laist, an analyst with the U.S. Marine Mammal Commission, told the March 8 Times of London.

“Most mammals are too big to get caught up in a plastic bag,” Laist continued. “The impact of bags on whales, dolphins, porpoises, and seals ranges from nil for most species to very minor for a few species. For birds, plastic bags are not a problem either.”

Activists Persist

Despite such assurances, the campaign against plastic bags shows no signs of letting up.

Earlier this year British Prime Minister Gordon Brown announced plans to charge supermarkets for handing out the bags. “The danger that single-use plastic bags inflict on the environment is such that strong action must be taken,” Brown said in the February 29 London Guardian. “If government compulsion is needed to make the change, we will take the necessary steps.”

The BBC recently reported towns throughout the UK are competing with one another to see which will be the first to ban the use of plastic bags. Similar efforts are underway in Ireland, Bangladesh, Thailand, Taiwan, and South Africa.

In the United States, San Francisco and Oakland last year banned the use of plastic bags in large supermarkets and pharmacies, and similar measures are under consideration in Santa Monica, California; New Haven, Connecticut; Annapolis, Maryland; and Portland, Oregon.

Heated Rhetoric

Leading the charge against plastic bags in the United States is the California-based Earth Resource Foundation (ERF).

Meshing the separate issues of plastic entanglement (fishing gear) and plastic bags, ERF’s “Sea Turtles Don’t Shop” campaign claims on the group’s Web site, “Over 100,000 marine animals DIE each year from plastic entanglement.”

Saying plastic bags are “made from petroleum, a nonrenewable resource,” ERF recommends, among other things, that consumers take their own cloth bags with them when they go shopping.

The campaign against plastic bags has tended to take on over-the-top rhetoric.

An August 2007 article by Katherine Mieszkowski in salon.com carried the title, “Plastic bags are killing us: The most ubiquitous consumer item on Earth, the lowly plastic bag is an environmental scourge like none other, sapping the life out of our oceans and thwarting our efforts to recycle it.”

Plastic Good for Environment

Angela Logomasini, director of risk studies at the Washington-based Competitive Enterprise Institute, says such rhetoric is far off the mark.

“In our energy-conscious age, the attack on plastic bags is perplexing,” Logomasini said. “Plastic bags have beat out paper bags in the marketplace because they are not only easier to carry and easier to store and transport, but also because they have important environmental benefits that also make them less expensive.

“For example,” Logomasini noted, “studies have shown that plastic bags require 40 percent less energy to make than paper bags, and they produce only 4 percent of the waste that paper produces. And if you are worried about carbon emissions, plastic bags produce 60 percent less ‘greenhouse gases.'”


Bonner R. Cohen, Ph.D. ([email protected]) is a senior fellow at the National Center for Public Policy Research.