Leibniz-Institut für Polymerforschung Dresden e.V. (IPF), Hohe Str. 6, 01069, Dresden, Germany.
Organische Chemie der Polymere, Technische Universität Dresden, 01062, Dresden, Germany.
Anal Bioanal Chem. 2018 Aug;410(21):5313-5327. doi: 10.1007/s00216-018-1185-5. Epub 2018 Jun 16.
In recent years, many studies on the analysis of microplastics (MP) in environmental samples have been published. These studies are hardly comparable due to different sampling, sample preparation, as well as identification and quantification techniques. Here, MP identification is one of the crucial pitfalls. Visual identification approaches using morphological criteria alone often lead to significant errors, being especially true for MP fibers. Reliable, chemical structure-based identification methods are indispensable. In this context, the frequently used vibrational spectroscopic techniques but also thermoanalytical methods are established. However, no critical comparison of these fundamentally different approaches has ever been carried out with regard to analyzing MP in environmental samples. In this blind study, we investigated 27 single MP particles and fibers of unknown material isolated from river sediments. Successively micro-attenuated total reflection Fourier transform infrared spectroscopy (μ-ATR-FTIR) and pyrolysis gas chromatography-mass spectrometry (py-GCMS) in combination with thermochemolysis were applied. Both methods differentiated between plastic vs. non-plastic in the same way in 26 cases, with 19 particles and fibers (22 after re-evaluation) identified as the same polymer type. To illustrate the different approaches and emphasize the complementarity of their information content, we exemplarily provide a detailed comparison of four particles and three fibers and a critical discussion of advantages and disadvantages of both methods.
近年来，发表了许多关于环境样品中微塑料（MP）分析的研究。由于不同的采样、样品制备以及识别和定量技术，这些研究几乎无法进行比较。在这里，MP 的识别是一个关键的陷阱。仅使用形态学标准的目视识别方法往往会导致重大错误，对于 MP 纤维尤其如此。可靠的、基于化学结构的识别方法是必不可少的。在这方面，经常使用的振动光谱技术以及热分析方法已经建立。然而，对于分析环境样品中的 MP，从未对这些从根本上不同的方法进行过严格的比较。在这项盲法研究中，我们研究了从河流沉积物中分离出的 27 个未知材料的单微塑料颗粒和纤维。依次采用微衰减全反射傅里叶变换红外光谱（μ-ATR-FTIR）和热解气相色谱-质谱联用（py-GCMS）结合热化学解吸的方法。两种方法在 26 种情况下以相同的方式区分了塑料与非塑料，19 个颗粒和纤维（重新评估后为 22 个）被鉴定为相同的聚合物类型。为了说明不同的方法，并强调其信息内容的互补性，我们举例详细比较了四个颗粒和三个纤维，并对两种方法的优缺点进行了批判性讨论。
