The 5p levy on plastic bags was introduced in England in 2015 and from 21 May 2021 retailers of any size (large, medium, small, micro and airport retailers) must charge a minimum of 10 pence for single-use carrier bags in England.[1]

As shoppers are now charged a levy on single use bags, there is a shift towards the use of ‘bags for life’ and retailers are also stocking a variety of bags including paper, plastic and cotton. But which is best for the environment?

How do you know which is the most sustainable?

To know the most sustainable solution it is important to base any decision based upon the impact on the environment.

A life cycle analysis (LCA) is the act of measuring the environmental impact of a product or service throughout its life cycle, from the resources used to create the product or service, throughout its use phase by the user, up until its final end of life destination.

An LCA measures the environmental impacts of each distinct part involved in creating and using products and services, such as energy used in production, fuel used in transport, and end of life ecological costs. This helps to compare between products, materials, and methods used, providing useful information from which to make decisions that could help the environment. LCAs can differ depending on the input.

What does an LCA on bags tell us?

The Environment Agency conducted an LCA on bags in 2011 to fully understand the environmental impacts of the different materials bags are made from throughout their life.[2] Figure 7.1 from the study displays the results.

 

This study compared bags for life (LDPE), conventional carrier bags (HDPE), durable plastic bags (PP), biodegradable bags (starch polyester bags), as well as paper and cotton.

The report concluded that the conventional HDPE bag had the lowest environmental impacts of all the lightweight bags in eight of the nine impact categories. The LDPE bag must be used five times to reduce its global warming potential (GWP) to below that of the conventional HPDE bag. When used five times, its impacts were lower in eight of nine of the impact categories.

A paper bag must be used four or more times to reduce its GWP to below that of the conventional HDPE bag but was significantly worse than the conventional HDPE bag for human toxicity and terrestrial ecotoxicity due to the effect of paper production.

The cotton bag has a greater impact than the conventional HDPE bag in seven of the nine impact categories, even when used 173 times.

A further 2019 study compared a single use HDPE carrier bag, which displays a GWP of 5 (grams of CO2 eq./kg or litre of packaged product) to a recycled paper bag (single use) which had a GWP of 17.[3]

In summary, from an LCA perspective, plastic carrier bags often have a lower environmental impact than alternative materials. But they should be reused as much as possible and disposed of correctly and recycled wherever possible.  

What is the plastics industry doing to further reduce the environmental impact of bags?

Including recycled materials in packaging can have environmental benefits, improving resource efficiency and saving carbon while reducing the demand for virgin raw material. The level of resources and carbon saved depends upon the level of recycled content alongside the application of the packaging and the recovery method employed.

How can you shop more sustainably?

The fundamental way to reduce the environmental impact of your bags whilst shopping is to reuse them as many times as possible and recycle them at the end of their life.

Are plastic bags recyclable?

Plastic bags - both single use and bags for life - are 100% recyclable.

What do I do with my bag at the end of its life?

Bags for life can be returned to a store and swapped for a new one (retailers will recycle the old one for you). Thin carrier bags can be recycled at most supermarkets, along with other plastic bags and wrapping at selected retailers and put it in their front-of-store collection points for recycling.

In the UK, most councils provide a collection service for plastic bottles, pots tubs and trays. However, very few councils collect flexible plastic packaging such as plastic film, wrappers and bags. This will change in the future as the government is undergoing consultations regarding the consistent collection of all plastic packaging from households and businesses from 2023.

In the interim, several major retailers have launched front-of-store collection points for consumers to return their bags, films, and flexible packaging for recycling in selected stores across the UK. Further information on collections in England is available here.

To further scale up the collection and recycling of this valuable material, the Flexible Plastic Fund, a first-of-its kind collaboration between major brands, retailers, recyclers, a producer responsibility compliance scheme, and an environmental charity has been set up. The £1m fund is intended to improve the recycling of flexible plastic packaging (bags, wrappers, and films), establish a stable value for the material and increase the availability of recycled plastic.

 

Which supermarkets are hosting return points?

Tesco has rolled out soft plastic recycling points to 171 stores in the South West of England and Wales, with plans to roll out to all large stores nationwide.  Tesco to launch UK’s biggest network of recycling points for soft plastic (circularonline.co.uk).[4]

Sainsburys are rolling out 524 collection points.[5]

Waitrose are rolling out a trial at 37 stores.[6]

Recycling units for ‘soft’ plastics will launch in 1,500 Co-op stores this month (July) and 2,300 stores by November.[7]