In recent years, plastic bags have been the target of a global crackdown. Single use plastic bags have been banned by many countries, states and cities globally in an attempt to curb the massive impact of plastics on the environment. But are such measures really effective? Let's see what the data has to say.
In 2002, Bangladesh became the first country in the world to ban single use plastic bags. Rwanda, Taiwan, China, and Macedonia have all followed suit. Many other countries have implemented plastic bag taxes or laws which require retailers to charge a fee for bags. Single-use plastic bags, also known as low-density polyethylene (LDPE) bags, have become a scapegoat for the massive problem of plastic pollution. But with more and more countries banning the bag, it's important to examine the data. Are plastic bag bans actually effective in reducing our impact on the environment?
The Environmental Impact of Plastic
Plastic takes over 400 years to break down, meaning that every piece of plastic which has ever been made still exists. In 2016 alone, an estimated 335 million metric tons of plastic was manufactured! Only about 9% of plastic waste is recycled. Much of the rest eventually ends up in the ocean where it is consumed by marine life. Birds mistake plastic waste for food, which can lead to starvation as their stomachs become full of plastic. Alarmingly, 95% of Great Shearwaters, 93% of Blue Petrels, and 80% of Northern Fulmars have plastic in their stomachs. Clearly, this is a huge problem!
Alternatives to Plastic Bags
Various alternatives to LDPE (single use) plastic bags are in use. One solution is for retailers to charge a small fee for a high-density polyethylene bag - a more durable plastic bag intended for reuse. Most supermarkets also offer 'green' bags and encourage customers to bring their own bags. These measures are intended to reduce the impact we have on the environment. But studies have shown that it actually takes more resources to manufacture alternatives to single-use bags! Potentially this could have a greater impact on the environment. Let's take a look at the data...
Based on a life cycle analysis of their manufacturing process, energy and resource consumption, single use plastic bags appear more environmentally friendly! For the amount of resources it takes to produce a 'green' bag, you would have to re-use at least ten times for it to have its intended effect. A heavy LDPE bag requires 4 uses, while a paper bag needs 3. But over 80% of Australians said they reuse supermarket bags as bin liners. How does this change our comparison?
If 40% of all single use plastic bags were reused, you would need to use your green bag 14 times to have the same environmental impact. If all plastic bags were reused, you'd need to use it 26 times! The plastic bag ban is looking shaky as a way of saving the world from plastic pollution!
Reducing Our Impact
Of course, this analysis is only based on the resources needed to make different kinds of bags. We haven't taken into account the typical usage patterns of these bags, or their impact on specific species or habitats. Single use plastic bags are known to cause a myriad of problems, particularly once they enter the ocean. But banning plastic bags alone aren't enough to save the planet. If we just replace one type of bag with another without changing our usage patterns, the world could end up worse off than when we started. The key to minimizing the environmental impact of our shopping bags is to reuse them as many times as possible. Banning plastic bags isn't useful on its own - instead, we need to focus on changing our habits.