Oligomers are a major fraction of the released submicrometre particles released during washing of polyester textiles

Abstract Synthetic textiles are a significant source of microplastic fibre pollution. While the microplastic fibre release mechanism during the washing of textiles is well studied, little is known about the release of nanoplastics. The first investigations on the nanoplastic fraction released during the washing and abrasion of polyester textiles have been published; however, questions were raised regarding the chemical composition of the observed submicrometre particles. Using a combination of analytical methods, we show here that 12 different polyester textiles released 4.6 × 10 10 to 8.9 × 10 11 particles per gram of textile during washing, with a mean size of 122–191 nm. The number of released submicrometre particles was not significantly influenced by the cutting method nor by the textile structure, but positively correlated ( P < 0.01) with the number of submicrometre particles present on the fibre surface before washing. We found that 34–89% of the extracted submicrometre particles were soluble in ethanol. These particles are most likely water-insoluble poly(ethylene terephthalate) oligomers. Our results clearly show the urgent need to better understand the contribution of water-insoluble oligomer particles to the pollution of the environment by anthropogenic nanoplastics.