Cotton is one of the world’s most popular and oldest biomaterials, accounting for around a quarter of all textile production. Yet its future as a cheap clothing staple is now in question as overproduction fuels environmental breakdown.
Intensive cultivation in this thirsty crop has been linked to increasing drought conditions. Aside from this, the plant requires massive amounts of fertilizer that leaches into waterways, contributing to habitat and biodiversity loss. Water usage doesn’t stop at cultivation and harvest either. Making a single cotton t-shirt requires a further 713 gallons of water.
The virtues of organic cotton
Some companies are opting for certified organic cotton cultivated without toxic chemicals. According to the Higg Materials Sustainability Index, organically grown crops have roughly half the environmental impact of conventional cotton. Companies looking to source organic cotton would do well to look at the guidance given by The Better Cotton Initiative, whose output dominates the organic cotton market.
However, there are sustainability problems with relying on virgin cotton sourcing, even when the products are organic. There are limits on how far fertilizer, water use, and land use can be reduced to meet demand. Another problem is the labelling around virgin materials. Sustainable cultivation certification schemes like The Better Cotton Initiative must negotiate a balance between the stringency of its sustainability criteria and the imperatives of meeting global demand with industrial production levels. It is challenging for a scheme to incorporate the preferences of diverse stakeholders along the supply chain which include both the consumer expectation of falling prices and the producers’ desire to maintain income levels.
Recycled cotton for maximal sustainability
For these reasons, some fashion companies are eschewing virgin cotton altogether, whether organic or not. Brands like US Back Beat Co., Re/Done, and eco-conscious Wolven have gone for recycled cotton, which Patagonia’s head of material development has deemed the “most responsible’ material from a carbon reduction perspective.
Recycled cotton can be made from waste at either the pre-consumer end of the supply chain or from discarded consumer items. Compared even to organic crops, recycled materials can offer greater sustainability gains as it eases both the social and environmental pressures associated with textile agriculture.
Like in polyester recycling, mainstreaming recycled cotton will depend on finding ways to recover second-hand yarn so that the fibres are as durable and functional as those made from virgin materials. Compared to research on the recyclability of polyester, there is less work on the quality of recycled cotton but the work that’s out there finds that in general, recycled cotton fibres from dyed fabrics sowed lowe quality once recovered. The best post-recycling quality was obtained from single-jersey griege cotton fabrics. Mechanical recycling methods like shredding also lowers the strength of the end product. Another problem in cotton recycling is finding efficient processes for separating cotton from the fibres it is blended with, commonly polyester.
Both problems of traditional cotton recycling– maintaining strength and separating belnds – are being tackled by several new textile recycling startups. Ervnu and Circ are two companies that recover cotton as well as polyester and nylon from used fabrics using proprietary technologies. Circ uses a combination of water, heat, pressure, and responsible chemicals to break down the textile and get 90 percent of the original materials. By 2021 they had dealt with 12 tons of clothing waste, but with investment backing from Patagonia, Japanese and Marubeni corporations, they plan to achieve 2 tons per day shortly.
A more established company is Worn Again Technologies, founded in 2005 in East London. It recycles cotton as well as polymers like polyester. It has gone one step further than its competitors by building a whole ecosystem for circularity. Its Swiss Textile Recycling Ecosystem project brings together fabric manufacturers, waste collectors, retailers, brand owners and technology providers around its demo plant in Winterthur Switzerland. This pilot plant will have 1000 tonne annual recycling capacity and the experiment will lay the groundwork for a planned full-scale plant in Copenhagen.
Once recovered, cotton can also be made into entirely new materials. The Natural Fiber Welding company, founded in 2015 by a chemistry professor at Bradley University, turns low-grade used cotton into a moisture-removing textile called CLARUS. The textile offers a replacement for oil-based synthetics ordinarily used in applications where maintaining dryness is important – in sportswear, for example. The founder has acquired a dozen patents with 100 more pending. Ralph Lauren is now using its products to achieve greater circularity in their clothing, such as in their RLX Clarus Polo.
Cotton for biodiesel
Although post-consumer waste in the cotton supply chain is a significant enough problem on its own, it is only part of the equation when it comes to transforming the industry. Cotton processing also contributes its fair share of unused materials.
The byproducts of cotton ginning are proving its circular value in central Kenya, where cotton-ginning factories are making biodiesel by crashing cotton seeds separated from the cotton bales during processing. This is part of a USAID project which has helping factory operators create biodiesel for sale to local cotton and food crop farmers, who use it to power irrigation systems. Currently, the programme is being hindered by a lack of financing for local farmers to obtain biodiesel-based water pumps. Nonetheless, the project gives a good model for building local resilience around the waste products of the cotton indsutry.
Bio-based alternatives for a biobased material
Cotton is a material that occupies a unique status within discussions around circularity. While most sectors are focusing on moving from petro-chemicals to biological feedstocks, cotton is already a renewable biomaterial. Nonetheless, its resource-intensive growth cycle and huge global demand combine to make it almost as problematic from a green standpoint as polyester and nylon.
Infinited Fiber makes cotton substitute textiles from low-impact, high-abundance biomass. Their feedstock is cellulose, found in every single higher plant on the planet. Because the substance is so common in the natural world, it gives manufacturers a huge range of choice in which species to use as feedstock – many of which will have dramatically lower fertiliser, water, and input needs compared to cotton plants. It can also be derived from cotton waste streams as well as from cardboard, paper, and agricultural residues like wheat and rice straw.
Infinited Fiber Company’s Infinna fibres could potentially replace jersey, denim, and woven fabrics, as well other cotton applications in hygiene products and wipes. It also offers easy substitution for manufacturers looking to make the circular transition, as it can be blended with conventional cotton as well as fibres from recycled textile waste. Infinited Fiber Company will open a 30, 000 tonne per year factory in Finland in 2024 to step up production to meet demand.
Cultural shifts
For circular strategies to make a real difference in reducing fashion’s impacts on the environment, retailers cannot just focus on innovative upcycling technologies. Retaining a business model that revolves around rapidly produced disposable items is not compatible with long-term sustainability goals, even if large-scale recycling is implemented. The fashion industry must now mount a dual-pronged attack on waste and emissions resource simultaneously. On top of partnering with recycling innovators, they must produce product lines built to last.
Of course, prioritising durability and quality in apparel entails a wider cultural shift both within the industry and across its consumer base. Today, the term ‘fashion’ does not just refer to the clothes we wear, but more broadly signifies a seasonal churn of aesthetic trends that disappear almost as soon as they emerge. This association between apparel and a constant stream of faddish novelty must be broken. Designers and manufacturers must pivot away from mimicking catwalk trends that change by the season and towards longer aesthetic cycles. Marketing has a role to play in inspiring consumers to value classic looks and durability over the fix of novelty, to prize material integrity as well as aesthetic appeal.