Brands rely on “recycled” clothing to achieve their sustainability goals. How are they made? And why is it even more difficult to recycle them?

Today, we make more clothes than ever. And the driving force behind this is primarily economic, rather than human need. Over the past decade, the term “circular economy” has entered the lexicon of the fashion industry, where materials are designed to be reused and recycled by design.

Yet we haven’t seen the same level of recycling in fashion as in other spaces, like plastic recycling, for example. And that’s mainly because garment-to-garment recycling is much more difficult.

The use of recycled polyester and cotton by brands such as H&M and Cotton On are key aspects of these companies’ sustainability initiatives, but the source of these recycled fibers is generally not clothing. Recycled polyester tends to come from plastic bottles and recycled cotton is usually made from manufacturing waste.

The thing is, most clothes just aren’t designed to be recycled. Even when this is the case, the fashion industry lacks the kind of infrastructure needed to truly embrace a circular economy model.

Why is recycling clothes difficult?

Recycling clothes is not like recycling paper, glass or metal. Clothing is infinitely variable and unpredictable. They are therefore not ideal for recycling technologies, which require a stable and consistent source material.

Even a seemingly simple garment can contain multiple materials, with fiber blends such as cotton/polyester and cotton/elastane being common.

Different fibers have different recycling abilities. Natural fibers such as wool or cotton can be mechanically recycled. In this process, the fabric is shredded and re-spun into yarn, from which a new fabric can be woven or knitted.

However, the fibers become shorter during the shredding process, resulting in lower quality yarn and fabric. Recycled cotton is often blended with virgin cotton to ensure a higher quality yarn.

Most fabrics are also dyed with chemicals, which may have implications for recycling. If the original fabric is a mixture of several colors, the new yarn or fabric will likely need to be bleached to be dyed a new color.

A complex garment such as a lined jacket easily contains more than five different materials, as well as trimmings including buttons and zippers. If the objective of recycling is to arrive at a material as close as possible to the original, it would first be necessary to separate all the components and fibers of the garment.

This is labor intensive and can be expensive. It is often easier to shred the garment and turn it into a poor quality product, such as shoddy used for insulation.

Read more: To make our wardrobes sustainable, we need to reduce the number of new clothes we buy by 75%

Industry Progress and Challenges

Companies such as BlockTexx and Evrnu have developed processes to recycle fibers from blended fabrics, although these recycled fibers are not yet widely available.

Using proprietary technology, BlockTexx separates cellulose (found in both cotton and linen) and polyester from textile and clothing waste for new uses, including new garments. And Evrnu has developed a type of lyocell made entirely from textile and clothing waste.

The Spanish company Recover meticulously sorts different types of cotton textile waste to produce high-quality mechanically recycled cotton fibre.

There is also biological recycling. Lint waste from the Rivcott cotton gin (or cotton machine) is composted to become fertilizer for a new cotton crop. The same is possible with the natural fibers of used clothing, after dyes and potentially toxic chemicals have been removed.

Synthetic fibers such as polyester and polyamide (nylon) can also be mechanically and chemically recycled. Chemical recycling by repolymerization (when the plastic fiber is melted down) is an attractive option, as the quality of the original fiber can be maintained.

In theory, it is possible to use polyester clothing as a source for this. But in practice, the source is usually bottles. Indeed, clothes are usually “contaminated” by other materials such as buttons and zippers, and separating them is too much work.

The plastic problem

Almost all recycled polyester in clothing today comes from recycled plastic bottles, rather than previous polyester clothing. This is significant considering that polyester accounts for over 60% of all fiber usage.

Given the rapid increase in the production of synthetic fibers and the still unknown impact of microplastics (which were documented in human placentas last year) – the question remains whether clothing should be made from biologically incompatible materials.

Polyester clothing, regardless of fiber sources, contributes to microplastic pollution by shedding fibers when worn and washed.

A new generation of synthetic fibers from renewable sources (recyclable and also biodegradable) offers a way forward. For example, Kintra fiber is made from corn.

Reduce and reuse before recycling

There is ample evidence that reducing clothing consumption by wearing clothes longer and buying second-hand clothes is preferable to buying clothes made from recycled fibers.

But even second-hand fashion is not without its problems considering the scale and pace of clothing production today.

Liz Ricketts of the US-based OR Foundation, a charity focused on sustainable fashion, paints a gruesome picture of the Kantamanto market in Ghana, where much of the world’s second-hand clothes end up (including from Australia) .

One way forward is for companies to take responsibility for end-of-life products. American fashion brand Eileen Fisher is a pioneer on this front.

The company has been buying clothes from its customers since 2009. These are cleaned and sorted, and mainly resold under the Eileen Fisher Renew brand.

Garments that are too damaged to be resold are handed over to a dedicated design team, who redesign them for resale as the Eileen Fisher Resewn collection. The scraps from this process are captured and turned into textiles for later use.

Read more: It’s time to make fast fashion an issue for its creators, not charities