You’ve heard it touted as the fast-growing, water-saving eco-solution to disposable plastic cutlery, toothbrushes and less sustainable types of fabric. But where it actually is helping solve the problem of single-use cutlery and the four toothbrushes you go through in a year (if you follow your dentist’s advice), bamboo fabric isn’t quite as straightforward. There are two overarching types of bamboo fabric, and we’re going to investigate them individually. The majority of this article will focus on the first and most common type of bamboo, bamboo viscose.
Is viscose made from bamboo?
The answer is, sometimes. We’ve written lots of articles about the various versions of viscose, including Lenzing modal, a brand-name version of rayon/viscose, and the trademarked version of lyocell, Lenzing Tencel. Almost all bamboo is viscose, but only some viscose is bamboo. Confusing right?
Just to reiterate, bamboo viscose is by far (can we underline that two times?) the most common variety of bamboo. You can interchange the words ‘viscose’ with ‘rayon’, but what we mean is that the most common variety of ‘bamboo’ fabric is a cellulosic fabric that was once bamboo, but has gone through so much chemical processing it’s really just the memory of the carcass of the bamboo plant.
If you’re in Australia or NZ, bamboo is unlikely to be labelled as ‘bamboo viscose’ or ‘bamboo rayon’. It’ll just be labelled ‘bamboo’, so if the fabric is soft or silky to the touch, that’s your clue that it’s a type of bamboo viscose, which is a semi-synthetic fabric; not a true synthetic like a fibre created of petrochemicals, but also no longer distinguishable as plant material under a microscope.
Why is bamboo labelled as “sustainable”?
The reason bamboo took the eco world by storm is that it is extremely fast growing- it can grow four feet in one day. It doesn’t require heavy water-use or fertilisers. There is plenty of bamboo out there that is completely organic even if it is not certified as such. The plant itself has potential to provide us with a sustainable fabric option.
How is bamboo made into fabric?
Bamboo fabric starts out as a wood pulp. This is dissolved by chemicals, and the resulting liquid, known as viscous, is pushed through something called a spinneret. When you push play-dough through a colourful plastic spaghetti-maker, and you get those stringy bits? A spinneret with viscous is like a very tiny and more professional version of that. Those fibres are dried, then woven or knit together to create fabric. They tend to be long fibres, and long fibres feel lovely and silky against the skin.
If you’re interested, we recommend checking out this video, which shows the processing of pulp to make viscose fibres. It’s interesting, we swear!
Is bamboo fabric actually sustainable?
So, is bamboo fabric sustainable or not? Despite the speedy growing process of bamboo and the low level of resource wastage, the demand for bamboo has grown so large, that it’s now commonly grown as a monocrop, meaning that the natural biodiversity of the landscape in which it would traditionally grow is eradicated.
When any ecosystem is thrown out of balance (thanks to humans), humans need to step in and try to fix the problem. In our arrogance (or driven by desperation to survive and necessity), we do not restore the ecosystem but instead try to silence it further with pesticides. And that’s what’s happening now with bamboo. It’s also not uncommon (thanks to a breed of capitalism that thinks we can only derive value from a landscape we whip into subservience- are we becoming too political?! Sorry we’ll stop) to fertilise the monocrops synthetically to try to develop a higher yield.
In China it’s also becoming common to clear natural forests to grow bamboo. Ironically, this brings us back to square one; viscose is made from wood pulp, and we are usually not growing that wood regeneratively.
Then there’s the chemical processing of bamboo viscose to consider. Bamboo pulp is dissolved in toxic chemicals such as carbon disulphide, which can be deadly to the workers who use it, and a disaster for the environment, when up to 50% of the chemical is not recovered and reused.
The spinning process uses sulfuric acid and zinc sulfate, which are incompatible with nature outside of a closed-loop chemical system; ‘water and air pollution caused by toxic compounds [has] darkened the image of the man-made cellulosics’ (Shen & Patel 2010).
Viscose fabrics have the worst ratings for CO2 emissions per kg of fibre of all fibres, which Shen & Patel (2010) say range from 1.2- 5.3 kg CO2/kg of fibre.
There are no organic options for any wood-pulp based fibre, because they all require processing with toxic chemicals. We’ve noticed some brands claiming they use organic bamboo. The bamboo plant may have been organic, but the chemicals applied in fabric manufacture aren’t, and so the finished fabric isn’t. These brands often suggest that they use chemicals that are non-toxic and are kept in a closed-looped system. Unfortunately, upon repeated contacting, the brands have ignored our requests for information about the particular chemicals used. This lack of transparency raises questions for us.
Can bamboo sustainably be turned into fabric?
Yes, we have an exception! It’s the second type of bamboo that we hinted at in the beginning, and it’s called bast bamboo. You can create a coarser, rougher fabric from bamboo without dissolving its pulp, by taking fibres from strands of the wood itself. Bast fibres are taken from the inside of the bamboo stalk, which are longer and therefore manage to create a slightly smoother weave. It ends up looking a lot more like linen than the soft bamboo you’re used to touching.
You can find certified organic versions of this, which is the ideal scenario; you know you’re avoiding the devastation of monocropping and toxic pesticides and fertilisers.
Are there any sustainability benefits to bamboo?
Refer back to the ‘growing bamboo’ section. It’s a fantastic option if you can find an organic bast bamboo- one of the most sustainable options out there, alongside hemp and linen.
In terms of bamboo rayon, the main benefit of a semi-synthetic fibre over a synthetic is that a semi-synthetic, under the right conditions, has the capacity to biodegrade in a matter of six weeks (Warnock et al. 2010).
How do I know if a bamboo product is sustainable?
What are the red flags to look for so you know whether the bamboo product you’re buying is sustainable? As we said, if it feels soft & silky, it’s unsustainable (until non-toxic solvents have been disclosed and proven as such).If it feels more like linen, it’s a pretty good option! If it’s organic, you know with certainty that it’s sustainable, and you should shout about your purchase from the rooftops! If people act less than impressed with how exciting your purchase is, you could shout it from social media and link this article, which either provides you with a scapegoat or will show them you were right to be excited all along.
What is bamboo fabric used for?
Just like you, bamboo fabric can basically be anything it wants to be (cute, right?). Bamboo fabric is used for a wide variety of items, from garments such as underwear and yoga-wear to household products like sheets and towels. Take sustainable brand Kappi, for instance: not only do they use bamboo for their toothbrushes, but they also use it as the material for their exfoliating gloves and reusable make up remover pads.
What does bamboo fabric feel like?
Bamboo is breathable, lightweight, moisture-wicking, and soft and smooth to the touch, and there is often a comparison between the feel of bamboo and the feel of fabrics such as cotton and silk. Also, as bamboo is a natural product, any garment made from 100% bamboo or a mixture of bamboo and another naturally-derived fabric like cotton or hemp is compostable at the end of its lifespan.
Here’s a few of our favourite brands that utilise bamboo (the sustainable type):