Heresy! The best choice for grocery bags may be plastic

Heresy! The best choice for grocery bags may be plasticOne of the more common environmental choices made every day is choosing paper or plastic or reusable bags to pack groceries. The choice usually isn’t difficult for the environmentally informed person; picking plastic grocery bags has even become anathema in some places. But a recent study suggests that, from an environmental standpoint, plastic groceries bags are actually the best option. With conflicting reports, what is an environmentally responsible person to do?

In spite of conventional wisdom, choosing among plastic, paper, or cloth grocery bags is not a straightforward decision. It depends on how often they are used. A recent unpublished study performed a life cycle assessment on seven types of bags to determine which one had the lowest environmental impact. The study concluded that the vilified HDPE grocery bag was in fact the best. According to the study, cotton bags would have to be reused 171 times, and paper bags four times, for them to have less of an environmental impact compared to a plastic bag. The study also noted that cotton bags are normally only used 51 times.

Of course, this study has not yet been peered review and released. Whether that is because it doesn’t fit into the environmental narrative that plastic is always bad, or that there are other problems with the study, isn’t clear. The study does not, however, seem to account for the effects of accumulation of plastic in the environment, such as its inclusion in the food chain and mountains of plastic debris in the oceans.

But the manufacture of paper and cloth bags has environmental impacts as well. The lesson here is that common sense may not always indicate which technology is greener. But common sense practices such as reusing bags, recycling bags, and reducing the number of bags used will always be the environmentally responsible thing to do, no matter what type of grocery bag you choose.

Because it’s not the technology that makes something green or not. It is how the technology is used that really matters.

If you want to stay away from plastic bags, here’s an option for a washable, reusable bag.