Technology and Society Laboratory, Empa-Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 901 St. Gallen, Switzerland.
Process Engineering Department, Eawag-Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600 Dübendorf, Switzerland.
Environ Sci Technol. 2020 Apr 21;54(8):4847-4855. doi: 10.1021/acs.est.9b07395. Epub 2020 Apr 6.
Microplastic fibers (MPFs) have been found to be a major form of microplastics in freshwaters, and washing of synthetic textiles has been identified as one of their main sources. The aim of this work was to use a panel of 12 different textiles of representative fibers and textile types to investigate the source(s) of the MPF during washing. Using standardized washing tests, textile swatches tailored using five different cutting/sewing methods were washed up to 10 times. The MPF quantity and fiber length were determined using image analysis. The 12 textiles demonstrated great variability in MPF release, ranging from 210 to 72,000 MPF/g textile per wash. The median MPF length ranged from 165 to 841 μm. The number of released MPF was influenced by the cutting method, where scissor-cut samples released 3-21 times higher numbers of MPF than the laser-cut samples. The textiles with mechanically processed surfaces (i.e., fleece) released significantly more (-value < 0.001) than the textiles with unprocessed surfaces. For all textiles, the MPF release decreased with repeated wash cycles, and a small continuous fiber release was observed after 5-6 washings, accompanied by a slight increase in the fiber length. The decrease in the number of MPF released is likely caused by depletion of the production-inherited MPFs trapped within the threads or the textile structure. The comparison of MPF release from laser-cut samples, which had sealed edges, and the other cutting methods allowed us to separate the contributions of the edge- and surface-sourced fibers from the textiles to the total release. On an average, 84% (range 49-95%) of the MPF release originated from the edges, highlighting the importance of the edge-to-surface ratio when comparing different release studies. The large contribution of the edges to the total release offers options for technical solutions which have the possibility to control MPF formation throughout the textile manufacturing chain by using cutting methods which minimize MPF formation.
微塑料纤维（MPFs）已被发现是淡水中微塑料的主要形式之一，而合成纺织品的洗涤已被确定为其主要来源之一。本工作旨在使用代表纤维和纺织品类型的 12 种不同纺织品的小组来研究洗涤过程中 MPF 的来源。使用标准化的洗涤测试，使用五种不同的切割/缝纫方法裁剪的纺织品样本被洗涤了多达 10 次。使用图像分析确定 MPF 的数量和纤维长度。12 种纺织品的 MPF 释放量差异很大，每次洗涤从 210 到 72,000 个 MPF/g 纺织品不等。MPF 的平均长度范围从 165 到 841μm。释放的 MPF 数量受到切割方法的影响，其中剪刀切割的样品释放的 MPF 数量比激光切割的样品高 3-21 倍。具有机械加工表面（即绒毛）的纺织品比未加工表面的纺织品释放出的 MPF 多得多（-值 < 0.001）。对于所有纺织品，随着重复洗涤周期的进行，MPF 的释放量减少，并且在 5-6 次洗涤后观察到少量连续纤维释放，并伴有纤维长度略有增加。释放的 MPF 数量减少可能是由于被困在线或纺织品结构中的生产继承的 MPF 耗尽所致。比较激光切割样品（具有密封边缘）和其他切割方法释放的 MPF，允许我们将边缘和表面来源的纤维与纺织品的总释放区分开来。平均而言，84%（范围为 49-95%）的 MPF 释放来自边缘，突出了在比较不同释放研究时边缘与表面积比的重要性。边缘对总释放的大量贡献为技术解决方案提供了选择，这些解决方案有可能通过使用最小化 MPF 形成的切割方法来控制整个纺织品制造链中的 MPF 形成。
