Any uncertainty in determining numbers of microplastics in the environment may be a barrier to assessing their impact and may stem from various aspects of methodologies used to quantify them. We undertook a comparison of approaches to quantify and characterize microplastics in 4 personal care products. The aim was not only to determine how many particles were present but to assess any differences due to the methods used. Counting of extracted microplastics was undertaken using particle size analysis, light microscopy, and imaging flow cytometry. Micro–Fourier transform infrared spectroscopy (µ-FTIR) was used to characterize the particles in each product. The mean size distribution of microplastics differed depending on the method employed, and it was apparent that imaging flow cytometry was affected by high background noise that may require staining of plastics to overcome. The application of µ-FTIR confirmed polyethylene as the microplastic in each product. Methodological challenges encountered in the study and the literature have highlighted the need for standardization of methods for determining microplastics. Environ Toxicol Chem 2022;41:880–887. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

中文翻译：

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在选定的个人护理产品中表征微塑料的不同方法的比较

确定环境中微塑料数量的任何不确定性都可能成为评估其影响的障碍，并且可能源于用于量化它们的方法的各个方面。我们对 4 种个人护理产品中微塑料的量化和表征方法进行了比较。目的不仅是确定存在多少颗粒，而且是评估由于使用的方法而产生的任何差异。使用粒度分析、光学显微镜和成像流式细胞术对提取的微塑料进行计数。微傅里叶变换红外光谱 (µ-FTIR) 用于表征每种产品中的颗粒。微塑料的平均尺寸分​​布因所采用的方法而异，很明显，成像流式细胞术受到高背景噪声的影响，可能需要对塑料进行染色才能克服。µ-FTIR 的应用证实了聚乙烯是每种产品中的微塑料。研究和文献中遇到的方法学挑战强调了确定微塑料的方法标准化的必要性。环境毒物化学2022；41：880–887。© 2021 作者。Wiley Periodicals LLC 代表 SETAC 出版的Environmental Toxicology and Chemistry 。