Are Plastic Bags the Greenest Option After All?


Image credit: Kate Ter Haar, used under Creative Commons license.

I must admit I have never really understood the environmentalist obsession with plastic bags. As I noted in my post on a ban plastic bags rap that went viral, I've always felt there are bigger issues to be tackled than what we take our groceries home in. (Not least, what groceries we actually take home!) Now one research paper is suggesting a rather scandalous notion—not only is the plastic bag not the biggest environmental issue out there, it may even be environmentally preferable to cotton or paper...Life Cycle Assessments Balance Competing Concerns
OK, as always we should note that Life Cycle Assessments are a tricky business. How, for example, do you weigh up the problems of litter, waste disposal and hazards to wildlife versus energy and resources used in manufacture. And just how do you measure a single use item like a plastic or paper bag versus a reusable item like a cotton tote?

Nevertheless, it's important that we try. And Martin Hickman reports at the Independent, one study commissioned by the UK Environment Agency suggests that plastic bags may be environmentally preferable to paper or cotton:

HDPE bags are, for each use, almost 200 times less damaging to the climate than cotton hold-alls favoured by environmentalists, and have less than one third of the Co2 emissions than paper bags which are given out by retailers such as Primark. The findings suggest that, in order to balance out the tiny impact of each lightweight plastic bag, consumers would have to use the same cotton bag every working day for a year, or use paper bags at least thrice rather than sticking them in the bin or recycling.

How Reused are Reusable Bags?
Without seeing the original paper, it's hard to assess whether these numbers are accurate—and there are some interesting assumptions being made. According to Hickman, for example, the researchers assumed that each reusable cotton tote is only used 51 times before being discarded—a number that sounds relatively low to me. We should also never forget—as the roundly debunked argument that Hummers are greener than Priuses has shown—we can't believe everything we read in a research paper.

Report "Suppressed"?
All this debate is complicated by the fact that the report—which was originally commissioned in 2005, and scheduled for publication in 2007, has yet to see the light of day. It is, apparently, still in the peer review process. The incredibly long time line has lead to accusations from Barry Turner, chief executive of the Packaging and Films Association, that the agency has tried to "suppress" the findings because they contradict the political zeitgeist of our times.

Whatever the truth about this particular report, it is one more reminder that we should always keep asking questions. And it is also a reminder that environmentalism is not about token items or must-have status symbols. It is about designing our lives to have the least negative impact possible—and to do that we have to keep learning.

More on Plastic Bags
Ban Plastic Bags Rap Goes Viral
Paper Bags or Plastic Bags: Everything You Need to Know
Plastic Bags are a Distraction - Monbiot

Tags: Life Cycle Analysis | Plastics | United Kingdom