Synthetic Shedding Nightmare: Blended Fabrics May Be Bigger Microplastic Threat than Pure Polyester

A new peer-reviewed study reveals that cotton-polyester blends, commonly used in everyday textiles, release significantly more microplastics than pure polyester fabrics. The research introduces a novel separation method to measure synthetic fibre shedding accurately, offering a validated approach to quantify microplastic pollution released during domestic and laboratory-scale laundering.

Long Story, Cut Short
  • Polyester-cotton blends shed more microplastics than 100% polyester during regular washing, according to a new study using advanced fibre separation techniques.
  • Researchers developed a chemical method to isolate polyester from cotton to accurately measure microplastic release from common textile blends.
  • The findings raise environmental concerns over widespread textile blends used in clothing, bedding, and industrial fabrics globally.
Researchers compared five fabric types: pure polyester, pure cotton, and three polyester-cotton blends with varying weaves.
Comparative Study Researchers compared five fabric types: pure polyester, pure cotton, and three polyester-cotton blends with varying weaves. [Illustrative image] AI-Generated / Gemini

Cotton-polyester blends release more microplastics than previously understood, especially compared to 100% polyester fabrics, a new fibre separation method has shown. The study, conducted by researchers from Deakin University (Australia), applied a modified ISO standard using acid digestion to distinguish synthetic fibres from biodegradable ones.

  • Polyester-cotton blends showed higher total shedding than pure polyester, largely due to cotton’s structural properties.
  • Researchers used FTIR and SEM tools to identify polyester fragments after chemical separation from cotton fibres.
  • These fibre blends are integral to global supply chains across apparel, home textiles, and institutional fabrics.

THE STUDY: Titled Decoding microplastic shedding from cotton/polyester blends: An analysis through fiber identification, the research was conducted by Yi Zhang, Abu Naser Md Ahsanul Haque, Shervin Ranjbar, David Tester, and Maryam Naebe. It was published in the journal Environmental Pollution.

  • The paper presents a novel method for isolating and quantifying synthetic microplastics from blended fabrics.
  • The publication introduces a validated analytical method to quantify polyester shedding from blended fabrics.
  • The method claims to correct longstanding misclassifications in past fibre-shedding research.
  • Researchers chemically removed the cotton content to isolate the synthetic fraction.
  • They then assessed microplastic weight and morphology with improved accuracy.
The method was validated using commercial laundry wastewater samples, successfully isolating polyester microplastics from cotton fibres.
The method was validated using commercial laundry wastewater samples, successfully isolating polyester microplastics from cotton fibres. The method was validated using commercial laundry wastewater samples, successfully isolating polyester microplastics from cotton fibres. [Illustrative image] AI-Generated / Gemini

DATA SNAPSHOT: Researchers compared five fabric types: pure polyester, pure cotton, and three polyester-cotton blends with varying weaves. The satin-weave 50:50 blend shed the most microplastics by weight. Polyester remained chemically stable during acid treatment, confirming its synthetic composition. After separation, polyester microplastics predominantly measured under 250 μm, though unseparated fibre lengths had previously reached several hundred microns.

  • A 50:50 satin-weave blend released more polyester than plain-weave variants under the same washing conditions.
  • Polyester fibres identified post-separation showed melted ends typical of industrial finishing processes.
  • The method was validated using commercial laundry wastewater samples, successfully isolating polyester microplastics from cotton fibres.

YES, BUT: While blended fabrics release more total fibres, not all of them are microplastics. Cotton fibres are biodegradable and should not be classified as plastic pollutants. Many past studies failed to distinguish fibre types, leading to inflated pollution estimates. The new method claims to correct this, though further refinement may be needed under varying water conditions.

  • Earlier methods using thermal analysis risked misclassifying fibre types due to overlapping decomposition temperatures.
  • Cotton fibres degrade in natural conditions, and acid treatment confirms their absence post-separation.
  • Laundry detergents and finishing chemicals may also interfere with microplastic measurements.

WIDER LENS: These findings have implications for the textiles industry, particularly given the dominance of cotton and polyester in global production. The newly quantified microplastic shedding highlights the need to evaluate the environmental footprint of blended fabrics across production and end-of-life stages.

  • The global poly-cotton market is projected to reach USD 20.6 billion by 2035.
  • Blended fabrics are prevalent in hotel linens, hospital textiles, uniforms, and casual clothing.
  • Blended fibres undergo heavy water-based dyeing, which may amplify microplastic release.

NEXT STEPS: The method could potentially be adapted for:

  • Other common blends such as cotton-acrylic or cotton-viscose
  • Hard water conditions
  • Integration with textile sustainability assessments
  • More laboratory-scale studies under different detergent and rinse conditions
How the Method Works
  • Researchers applied a modified ISO protocol using sulphuric acid digestion to break down the cotton component in blends.
  • The process retained polyester integrity, allowing post-treatment identification of synthetic microplastics in mixed-fibre fabrics.
  • FTIR and SEM imaging confirmed polyester morphology and chemical signature after cotton fibres were fully digested.
  • The method was tested successfully on samples from both lab-washed textiles and commercial laundry wastewater.
  • The technique allows for fibre-specific quantification, correcting past overestimations of synthetic microplastics from textile blends.
Fabric Types Compared
  • The study tested five fabrics: 100% polyester, 100% cotton, and three polyester-cotton blend variations.
  • A 50:50 satin-weave blend released the highest volume of polyester microplastics during laboratory washing.
  • All polyester-cotton blends shed more total fibre than the pure polyester control under standardised conditions.
  • Polyester fibres in blended fabrics remained chemically stable even after exposure to sulphuric acid digestion.
  • Polyester microplastics from blends mostly measured under 250 μm after cotton fibre removal and filtration.
 
 
  • Dated posted: 31 July 2025
  • Last modified: 31 July 2025