Microplastics: study highlights the drawbacks of recycled polyester

In a report of around 40 pages, the Dutch NGO Changing Markets casts doubt on polyester’s virtuous image, suggesting it releases far more microplastics than virgin polyester, according to research conducted at Çukurova University in Turkey.

The university carried out tests on 51 “representative” garments from the product ranges of the brands Adidas, H&M, Nike, Shein, and Zara. The document, reviewed by FashionNetwork, indicates that recycled polyester sheds 54.8% more microplastic particles. The NGO believes this figure may even be an underestimate.

Changing Markets argues that the polyester presented as recycled by Shein is not actually recycled. This appears to be borne out by the platform itself, as the word “recycled” has disappeared from the product pages of certain items. According to the study, this “polyester fraud” is commonplace in the textile industry, with the study noting evidence of similar practices at H&M and Nike.

When Shein products are excluded from the analysis, the volume of microfibres released is 72% higher than for virgin polyester. The document also notes that microfibres from recycled polyester are 20% smaller than those released by virgin polyester.

Use of bottles under scrutiny

Why the disparity? The study offers little explanation, simply noting that recycling processes, whether chemical or mechanical, weaken polymer chains, creating shorter, more imperfect molecular structures.

However, this is not the study’s main focus, which primarily targets the conversion of plastic bottles into polyester, with 98% of recycled polyester not coming from recycled textiles and clothing. Changing Markets likens this to a form of greenwashing, and argues that the practice misleads consumers about the supposed environmental virtue of these products.

“Recycled polyester has become a practical solution for the industry, allowing brands to claim progress in reducing their reliance on virgin plastic while increasing overall synthetic fibre production,” reads the study. “Textile Exchange data makes this clear: although recycled polyester volumes increased last year, its overall market share fell from 12.5% to 12%, as virgin polyester grew even faster.”

Disputed findings

Nike proved the most polluting (for both virgin and recycled fabrics), ahead of Adidas: Nike’s recycled polyester shed over 30,000 fibres per gram of garment on average, nearly four times more than H&M and seven times more than Zara.

Adidas maintains that it sees “an environmental benefit in using recycled polyester,” a spokesperson told AFP, because “no crude oil needs to be processed and plastic waste is reused.”

“Compared with virgin polyester, it generates far fewer greenhouse gas emissions,” continued the German sportswear company, citing other scientific studies, such as that by the NGO Microfibre Consortium, which find no significant differences between recycled and virgin fibres when it comes to microfibre shedding.

“The H&M Group shares concerns about the environmental impact of fibre fragments,” the Swedish brand told AFP, pointing out that polyester accounts for only 22% of its production and saying it is working in particular on “research into production processes that reduce the release of particles.”

For now, Nike, Shein, and Zara have not responded to AFP’s requests regarding the study’s findings.

FashionNetwork.com with AFP