How Eco are Plastic Bag Alternatives?
Sales of single-use plastic carrier bags in the UK have dropped by more than a whopping 95% since charging was introduced in October 2015.
The average person now buys just 4 single use plastic bags a year from the main supermarket retailers, compared with 140 in 2014. In fact, many supermarkets have stopped selling them and now only offer sturdier Bags for Life.
The charge has certainly helped reduce our consumption of single use plastic, but how do the eco credentials of the alternatives stack up in comparison?
Paper bags are often hailed as the eco alternative to plastic and while they do have many benefits, such as being made from a renewable source, one of the main downsides is that they fall apart very easily. They are difficult to reuse more than a couple of times which, in a way, actually makes them more disposable than plastic.
The best way to use paper bags is to avoid over filling or filling with wet/chilled items, to ensure they can be reused as many times as possible. Also, make sure they are made from recycled content, or from an ethical and sustainable source.
Bag for Life
Although still made from plastic, these bags are durable and designed to be reused multiple times. Some are made from a non-woven polypropylene which gives a more fabric like feel.
However, research shows that we still buy an average of 54 bags per household per year so we’re still viewing them as single use bags and they’re not being used to their full potential.
Cotton bags can be kept in rucksacks and handbags and are easily machine washable. They’re great for those times when you’re out and about and have to pop to the shops for a few items. Many of us will have a collection of cotton bags that we’ve acquired over the years and they’ve become a popular advertising tool for retailers, but it’s important to remember that cotton still has a high environmental impact. The growing process uses vast amounts of water and land, and pesticides if non-organic.
Jute and hemp bags
These bags are more robust than cotton. Jute is efficient to grow, doesn’t require vast amounts of water or pesticides, and takes minimal processing to make it into a usable fibre. It’s more sustainable than cotton and can be grown in the UK, although 90% of the world’s jute is grown in Bangladesh.
Hemp is a highly sustainable, low-impact crop that requires very little water, few pesticides and relatively little land to grow. Hemp has not had the industrial support of its mainstream counterparts, such as cotton, so its growth as an industry has been stunted. Demand is lower than that of other fabrics and therefore it is more expensive.
Biodegradable and compostable bag (bioplastics)
Most biodegradable and compostable plastics are bioplastics, made from plants rather than fossil fuels. Biodegradable plastics can be broken down by microbes and compostable bioplastics can be turned into compost. Bioplastics are not the same as oil derived plastics although they can look the same, which causes confusion when it comes to disposing of them. Bioplastics only break down in specific conditions which require a specialist industrial process. They cannot be recycled in the same way as oil derived plastics so it’s a tricky material to deal with once it’s reached its end of life.
So which of these materials is the best alternative to single use plastic? Well, it really depends on how much you use them.
A UK study found that to have lower global warming potential than single-use plastic bags:
- paper bags should be used three times
- plastic Bags for Life should be used four times
- non-woven polypropylene Bags for Life should be used 11 times
- cotton bags should be used 131 times.
As with products in general, reusability is the key to increasing sustainability. Using a bag just once, whether it’s plastic, paper, cotton etc, is always going to be bad for the environment in varying degrees. Recycling it is better than throwing it away, but reusing it endlessly is even better.
Overall, the best bag is the one you already own.