Views that plastic bags are worse for the environment than so-called sustainable bags are narrow and there is more than meets the eye, argues regional director of PlasticsEurope Jan-Erik Johansson.
As plastic bags are being discussed across the country, it is often argued that they are less sustainable than other options. However, a thorough examination of the bags’ environmental value rapidly reveals that things are more complex than meets the eye.
Attacking plastic bags might be an easy solution, but eliminating their use won’t actually do any good for the environment.
First of all, we need to put the matter into perspective: of all the household waste going to landfill in the UK, plastic bags constitute a mere 0.3%, of all waste going to landfill it is 0.05%. In addition, plastic bags today use 70% less polymer than those used 20 years ago. They do more with less.
Independent research has shown that plastic bags have positive environmental credentials compared to alternatives which are currently being championed as more sustainable.
For example, a study commissioned by the Australian Department of the Environment and Heritage shows that reusable bags made from plastics are better than cotton bags.
Cotton consumes the enormous quantity of 10.000-30.000 litres of water per kg, while around 10% of the world’s pesticides and 25% of the world’s insecticides are used to grow cotton. Also, during their useful life, cloth bags need to be washed regularly – often requiring harsh detergents to ensure elimination of bacteria and odours.
Other studies confirm the environmental credentials of plastic bags like the 2004 report commissioned by Europe’s biggest retailer Carrefour. It compared the overall ecological footprint of several different ways to carry a year’s grocery shopping home.
It found that re-using plastic bags performed best for all environmental indicators. Because plastic bags are so much lighter than other bags they use fewer resources in production and less energy to transport them, which saves even more greenhouse gas emissions.
A Defra survey found in 2002 that 80% of UK households were reusing their plastic carrier bags. At the end of their useful life, they can be recycled or processed to recover energy from them.
Putting plastic bags in landfill would be a waste of resources and equivalent to burying energy back in the ground. Banning or taxing plastic bags runs the risk of encouraging a switch to less sustainable alternatives and thus undermining environmental protection – and Defra agrees with me in this. Campaigns against plastic bags are rarely based on science and solid facts.
In fact, the latest assessment of the impacts of a ban on plastic bags in San Francisco show a clear switch to higher-impact paper bags – with a high frequency of double-bagging to compensate for their lack of strength (www.use-less-stuff.com).
It is very sad that marine mammals are affected by marine litter and ocean-borne debris but the blame can’t be put onto plastic shopping bags. Plastic bags have even been accused of causing the death of marine mammals, a charge that Greenpeace doesn’t think holds true: “It’s very unlikely that many animals are killed by plastic bags. The evidence shows just the opposite,” said Greenpeace marine biologist David Santillo in an interview with The Times on 8 March 2008.
Most deaths are in fact caused when sea creatures become entangled in fishing gear, ropes, lines and strapping bands either lost or thrown overboard from fishing boats and other vessels.
Rather than campaigning against plastic bags, governments should work with other stakeholders to educate consumers to reuse their shopping bags and improve their waste management by creating recycling options and by reducing landfill – a source of both litter and methane, a greenhouse gas 23 times more powerful than CO2 when products other than conventional plastics are buried.
Environmental issues need to be considered from a holistic point of view.
We have to scrutinise the entire lifecycle of products to be able to judge them fairly. Life-cycle assessments, like Carrefour’s study quoted above, demonstrate that plastic bags are of great value for the environment when used responsibly, re-used and then recycled or recovered.
The problem of littering is caused by people’s behaviour and the lack of access to disposal bins for used products, not by the material itself.
To foster a responsible attitude to the plastic bag we must through education change the perception of society that the plastic bag is a cheap disposable product to understand the value of re-using these products and the net environmental contribution they make when compared with alternatives.
The European plastics industry supports a responsible use of plastic bags to ensure that the number used are kept to a minimum.
