Decoding microplastic shedding from cotton/polyester blends: An analysis through fiber identification

Microplastics have joined a growing list of environmental pollutants that affect the ecosystem in general, as well as the health of land and sea fauna and humans. Textiles are a major source of microplastics, led by the release from polyester fibers that are two-thirds of global textile production. Polyester is used both in filament and staple fiber form, while staple fibers are more prone to shedding due to their shorter size, and therefore a greater number of fibers ends. Despite staple polyester fibers being popular for blending with natural fibers (mostly cotton) to produce a wide variety of garments, current literature has concentrated on reporting the release of polyester from 100 % polyester fabrics rather than blends. These blends make up everyday items such as sheets, pillowcases, and clothing. However, the true shedding characteristics of polyester fibers when they are used in a blend are unclear. This paper, for the first time, employs a chemical separation method to accurately quantify the proportion of polyester shed from cotton/polyester blend fabrics. By analyzing fabrics with different structures, this study provides a realistic assessment of microplastic shedding during regular use, offering valuable insights for developing more sustainable textiles and reducing environmental pollution. The accuracy of the proposed method was also validated by testing wastewater from commercial slurry. Results confirmed that the majority of the cotton fibers were effectively removed using this technique, leaving the polyester fibers intact, and facilitating precise measurement of the quantity of microplastics. It was observed that both the weave structure and the proportion of polyester in the blend can affect the microplastic release. The shedding phenomenon is observed significantly higher for cotton/polyester blends compared to polyester fabric alone. Overall, this study provides a clear understanding of the shedding behavior of polyester from blend fabrics, offering valuable evidence for the mechanism of microplastic formation and release.