3 March 2008The Guardian
How quickly the world turns. Last July, in the BBC's political satire, The Thick of It, the Daily Mail's night editor remarked: "It's not like we're the Independent. We can't just stick a headline saying CRUELTY then stick a picture of a dolphin or a whale underneath it."
Roll to last Wednesday, and Daily Mail readers were greeted with a picture of a turtle tangled in plastic bags under the headline "BIN THE BAGS". When the Independent and the Daily Mail are both campaigning against plastic bags, you can be sure there's a fair spread of public opinion against their target.
When Marks & Spencer join the fray by introducing a 5p charge on all bags, you can be sure that there's near unanimity. Saying "yes" when the disapproving cashier asks if you're absolutely certain you want a plastic bag is fast becoming moral equivalent to clubbing baby seals. For fun.
What did the humble plastic bag do to attract such ire? Its crimes seem numerous. Carrier bags can take a thousand years to decompose, and so litter the environment and harm wildlife. Producing bags pollutes air, water and soil. Transporting them generates carbon, contributing to climate change. Many of us don't even recycle or re-use the things.
We need to get shopping home from the supermarket - or farmers' market, or whatever - somehow. Producing anything, whether a disposable carrier or organic Fairtrade canvas bag, is going to generate pollution, as is transporting it to stores. The question is whether plastic bags are worse than the alternatives.
In a shock result, plastic bags seem to beat the traditional brown paper bag hands-down in the eco stakes. A report (pdf) for the Australian government revealed: "The making of a plastic bag uses up to 40% less energy, produces up to 80% less solid waste, 72% less atmospheric emissions and 90% less waterborne waste, than a paper bag."
The study also argued that as plastic bags are far lighter and more compact than paper bags, they generate less emissions through transport. Using recycled paper for the bags clouds the issue a little, but the coating required to make paper bags water-resistant causes further damage.
Buying a few durable bags and re-using them each time you visit the supermarket, however, wins hands down. Stronger bags - whatever they are made of - individually generate far more environmental damage than a single thin plastic bag, but as they are regularly used cause far less harm over their lifetime.
This only holds true if they're actually re-used, though. Anecdotally, many of us can admit buying several bags for life, canvas shoppers, or other environmental alternatives to carriers, only to leave them in the boot of the car, or in a kitchen drawer. Re-usable bags are also fairly useless for spontaneous food shopping after work.
Pictures of animals trapped in, or trying to eat, plastic bags upset many people. This consequence of the durability of plastic bags, and people's readiness to litter, is the most emotive argument against plastic.
There have been positive steps in tackling this. Many new carrier bags are degradable: they are broken down by light, and decompose far more quickly than traditional bags. The average time is 18 months, though some can decompose in just 60 days. Tesco pledged in 2006 to replace all their carrier bags with this variety. Switching to these bags, it's worth noting, would cost considerably less than the 5p-a-time M&S is to charge for old-style carriers.
No-one is suggesting carrier bags are good for the environment - but they are much less bad than many of us think. They use very little raw material, are very strong for their size, and thanks to their lightness it's not an especial loss if people don't bother to recycle. They are also one of the easiest items to re-use for most households.
Anyone who believes they are cutting their carbon footprint by cutting down on plastic bags is sorely mistaken. The average UK adult produces about 11 tonnes of carbon dioxide a year. Just 2 kilograms of this comes from plastic bags. Driving your car just over 100 metres generates the same amount of carbon dioxide as a plastic bag.
Carrier bags are at worst a minor evil. The UN has branded climate change the "greatest challenge facing humanity in the 21st century". In this context, the current hysteria about plastic bags is like complaining about traffic wardens during a world war. Have we really got nothing better to do?
