Tuesday, November 10, 2009

On The Search For Most Green Grocery Bag

How much and what materials reusable paper, plastic, and fabric bags actually save depends largely on the life cycle of the bag, Fox news reports today. An analysis of a bag’s life cycle follows each bag from raw material through production and distribution and to the consumer's hands and tells a lot about the kind of impact using bags of all sorts has on the environment. A life-cycle analysis also takes into account whether a bag is reused, recycled or thrown in the garbage.

Fabric Totes: Some retailers and manufacturers opt for elaborately designed reusable fabric bags (commonly made from cotton) over custom printed poly bags; because of the machinery involved, however, the cotton-farming process is extremely fossil-fuel-intensive and according to the Pesticide Action Network of North America (PANNA), conventionally grown cotton uses more insecticides than any other single crop. Worldwide, cotton is responsible for 25 percent of all chemical pesticides (insecticides, fungicides and herbicides ) used on American crops. Chemical fertilizers are used to enrich the soil. Most of the cotton grocery bags are woven outside the U.S. where labor is less costly, but that increases the use of fossil fuels in getting them from the factory to American shores. Evidently, the life-cycle analysis of reusable cloth bags doesn't sound too green.

Paper bags: The process for making paper bags is also far from ideal; huge machines log, haul, and pulp trees. The entire paper-making process is heavily dependent on chemicals, electricity, and fossil fuels. To the paper industry's credit, however, it says it's been working to make its process cleaner and more efficient.

Plastic bags: Surprisingly, plastic may be greener than paper. The EPA reports that making paper bags generates 70 percent more air pollution and 50 times more water pollution than making plastic bags. The former also uses more energy and generates more solid waste.

Many manufacturers make plastic bags by pulling ethane gas out of natural gas; through a process of heat and pressure, the ethane is made into long chains of hydrogen and carbon which can be formed into polyethylene and then into custom plastic bags, a process commonly regarded as much a more efficient process than milling paper.

So do plastic bags come out on top? What happens when all three kinds of bag are thrown in the trash? For most purposes, it's all about space, and with the EPA stating that nearly 100 landfills close nationwide every year because they're full, every bit saved counts.

Plastic bags in general take up a lot less space in a landfill than paper bags. As an example, you could put 10,000 plastic bags in the trunk of your car, but it would take a warehouse to store 10,000 paper bags. And according to the American Chemistry Council, it takes 91 percent less energy to recycle a pound of plastic than it takes to recycle a pound of paper.

So between paper and plastic, who’s the winner? Experts agree that each has its merits and drawbacks and that the issue with all packaging is chiefly what the consumer does with it after its initial use.

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