The amount and characteristics of plastic waste in the environment are closely monitored with the regular expansion of their collection to smaller debris sizes and new compartments, such as atmosphere, soil and even food. These data, subject to constant re-evaluation, are necessary to assess the threat that plastic particles pose. In this article, we take stock of the most recent measurements of their size distribution on the ocean surface. We confront the observed size distribution to the commonly invoked degradation modes of plastics and propose a scenario that accounts for the quite unusual features of the size distribution of floating debris. We conclude that delamination alone could be a major mechanism explaining the large number of small microplastics (<150 μm) in the ocean.

环境中塑料垃圾的数量和特征受到密切监测，定期将其收集范围扩大到较小的碎片尺寸和新的隔间，例如大气、土壤甚至食物。这些数据需要不断重新评估，以评估塑料颗粒构成的威胁。在本文中，我们评估了它们在海洋表面上的尺寸分布的最新测量结果。我们将观察到的尺寸分布与常见的塑料降解模式进行对比，并提出了一个方案，该方案解释了漂浮碎片尺寸分布的非常不寻常的特征。我们得出结论，单独的分层可能是解释海洋中大量小型微塑料（<150 μm）的主要机制。