Tuesday, June 19, 2012

WSJ.com - Bans on Plastic Bags Harm the Environment


WSJ.com - Opinion: Bans on Plastic Bags Harm the Environment


With the urging of environmental groups backed by the celebrity firepower of actress Julia Louis-Dreyfus, the city of Los Angles banned plastic supermarket bags last week. The law received added support from the Los Angeles Times, which published a house editorial encouraging the city council to enact the ban. Without presenting any quantitative evidence, the editors wrote that plastic bags pose a "huge cost to the environment" and that reusable totes and paper bags are "better options." Unsupported claims to this effect are widespread in the press and among advocacy groups, but they are at odds with scientific data.

In 2011, the United Kingdom's Environment Agency released a study that evaluated nine categories of environmental impacts caused by different types of supermarket bags. The study found that paper bags have a worse effect on the environment than plastic bags in all nine impact categories…

Furthermore, the study found that the average supermarket shopper would have to reuse the same cotton tote from 94 up to 1,899 times before it had less environmental impact than the disposable plastic bags needed to carry the same amount of groceries…

For example, a shopper would need to reuse the same cotton tote 350 times before it caused less fresh water aquatic ecotoxicity than all of the plastic bags that it would replace over this period. Given the improbability that the same cotton tote would last that long (its expected life is 52 reuses), in most cases plastic bags will have less environmental impact.

The environmental impacts of supermarket bags are dominated by the energy and raw materials needed to manufacture them. Plastic bags are inexpensive because relatively small amounts of energy and raw materials are needed to make them. These same attributes that make plastic bags affordable and light also make them easier on the environment than alternatives like paper bags and reusable cotton totes.

The study did find that with moderate reuse, plastic totes made from polypropylene are better for the environment than disposable plastic bags, but this doesn't negate the fact that standard plastic bags are a more environmentally friendly choice than so-called green alternatives like paper bags and reusable cotton totes. Thus, when governments outlaw plastic bags to "improve the environment," they actually create more pollution.




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