Microfibres from natural sources, like the cotton used to make jeans, could be just as damaging
Over the last few years many of us have become familiar with the word ‘microfibres’ – tiny pieces of the fabric used to make our clothes, which break off when we wash and wear them.
In most cases, when we talk about microfibres we think of clothes made from synthetic fabrics like polyester or nylon, which are made from the same oil-based compounds used to make many other plastic items, like straws or carrier bags.
But now scientists are beginning to ask a troubling question – could ‘natural’ microfibres, like cotton, also be a problem?
It’s estimated that on any given day half the world’s population could be wearing jeans. But our love affair with this wardrobe staple is having an impact on the environment.
In fact, the study found that fibres from denim jeans were so widespread that they made up between 10%-23% of ALL the microfibres found during the research.
Other findings show:
- 1 pair of used jeans can shed 56,000 microfibres per wash
- More than 13 million denim microfibres could be released from laundry in just 1 Canadian household every year
Until now, scientists studying microfibre pollution have tended to focus on synthetic fibres which present a potentially serious threat to marine environments and wildlife. Around 500,000 tonnes are released into the ocean every year from washing clothes and, once in the ocean, they last for a very long time.
To date, researchers have been less concerned by the scale and impact of ‘natural’ microfibres on the assumption that, as an organic substance, they will rapidly degrade in ocean environments.
But Toronto’s study suggests that may not the case. It shows that ‘natural’ microfibres can last a long time in the environment, certainly long enough to be transported great distances on Arctic ocean currents.
And other research has suggested that there may actually be more ‘natural’ microfibres in the ocean than synthetic. If that is true then many of the natural microfibres shed from clothes made decades ago, before the rapid growth in the use of synthetics, could still be floating around in the oceans today.
Not that ‘natural’
One of the reasons suggested by the Toronto researchers that ‘natural’ fibres do not break down in the environment, is the addition of chemicals during the manufacturing process. These include things like flame retardants or, in the case of Toronto’s study of jeans, the addition of indigo dyes.
It could be these types of chemical processes that are responsible for slowing down the degradation of natural fibres in the environment.
In fact, Toronto argues that these processes modify natural fibres to such an extent that they do not refer to denim microfibres as ‘natural’ at all. Instead, Toronto prefers to call them ‘AC’ microfibres or ‘Anthropologically Modified Cellulose’.
All naturally sourced fibres go through a series of chemical processes whilst being turned into fabrics and garments and, just like denim, they will shed microfibres when they are washed.
Should We Stop Buying Synthetic?
If natural fibres like cotton shed as many (or more) microfibres than synthetics fibres like polyester, and they last a long time in the environment, should we stop buying synthetic clothes and only buy natural instead?
This is an argument often put forward by some campaigners who believe that naturally sourced fibres are a more sustainable choice.
But based on the latest microfibre research the short answer must be, no.
There are other important environmental considerations too. Cotton, for example, takes huge amounts of water to produce, mainly due to it being such a thirsty crop to grow.
Analysis by Levi, more than a decade ago, showed that a single pair of jeans consumed 3,781 litres of water across its entire lifecycle, with almost 70% of that used in just growing cotton.
That’s more water than an average person will drink in more than three years – for just one pair of jeans.
Further Study is Required
Further research will be needed to understand just how long these ‘natural’ microfibres last in the environment, the impact they have and, crucially, what damage they can cause to delicate ecosystems, wildlife and us.
But Toronto’s study of denim microfibres shows that we can no longer talk only about microplastics when we talk about microfibre pollution. Naturally sourced fibres in our clothes could present as big a problem to our rivers, oceans, wildlife and us.
You can read more about the research into denim and microfibres in our Q&A with Samantha Athey, Microfibre Scientist.
Or read more about the practical steps you can take to minimise microfibre pollution from your laundry.