Department of Environmental Sciences, Informatics, and Statistics; Ca' Foscari University of Venice, Via Torino, 155, 30172, Venezia-Mestre, Italy.
Department of Environmental Sciences, Informatics, and Statistics; Ca' Foscari University of Venice, Via Torino, 155, 30172, Venezia-Mestre, Italy; Institute of Polar Sciences, CNR-ISP; Campus Scientifico - Ca' Foscari University of Venice, Via Torino, 155, 30172, Venezia-Mestre, Italy.
Environ Pollut. 2023 Jun 1;326:121511. doi: 10.1016/j.envpol.2023.121511. Epub 2023 Mar 24.
Tire wear particles (TWPs) are one of the environment's most important emission sources of microplastics. In this work, chemical identification of these particles was carried out in highway stormwater runoff through cross-validation techniques for the first time. Optimization of a pre-treatment method (i.e., extraction and purification) was provided to extract TWPs, avoiding their degradation and denaturation, to prevent getting low recognizable identification and consequently underestimates in the quantification. Specific markers were used for TWPs identification comparing real stormwater samples and reference materials via FTIR-ATR, Micro-FTIR, and Pyrolysis-gas-chromatography-mass spectrometry (Pyr-GC/MS). Quantification of TWPs was carried out via Micro-FTIR (microscopic counting); the abundance ranged from 220,371 ± 651 TWPs/L to 358,915 ± 831 TWPs/L, while the higher mass was 39,6 ± 9 mg TWPs/L and the lowest 31,0 ± 8 mg TWPs/L. Most of the TWPs analyzed were less than 100 μm in size. The sizes were also confirmed using a scanning electron microscope (SEM), including the presence of potential nano TWPs in the samples. Elemental analysis via SEM supported that a complex mixture of heterogeneous composition characterizes these particles by agglomerating organic and inorganic particles that could derive from brake and road wear, road pavement, road dust, asphalts, and construction road work. Due to the analytical lack of knowledge about TWPs chemical identification and quantification in scientific literature, this study significantly contributes to providing a novel pre-treatment and analytical methodology for these emerging contaminants in highway stormwater runoff. The results of this study highlight the uttermost necessity to employ cross-validation techniques, i.e., FTIR-ATR, Micro-FTIR, Pyr-GC/MS, and SEM for the TWPs identification and quantification in the real environmental samples.
轮胎磨损颗粒（Tire Wear Particles，TWPs）是环境中最重要的微塑料排放源之一。在这项工作中，首次通过交叉验证技术对公路雨水径流中的这些颗粒进行了化学鉴定。提供了一种预处理方法（即提取和纯化）的优化，以提取 TWPs，避免其降解和变性，从而防止识别率降低，并避免在定量分析中出现低估。通过傅里叶变换衰减全反射（FTIR-ATR）、微傅里叶变换（Micro-FTIR）和热裂解-气相色谱-质谱联用（Pyrolysis-gas-chromatography-mass spectrometry，Pyr-GC/MS），使用特定标记物对 TWPs 进行了鉴定，比较了真实雨水样本和参考材料。通过 Micro-FTIR（微观计数）对 TWPs 进行了定量分析；丰度范围从 220,371 ± 651 TWPs/L 到 358,915 ± 831 TWPs/L，而更高的质量为 39.6 ± 9 毫克 TWPs/L，最低的为 31.0 ± 8 毫克 TWPs/L。分析的大多数 TWPs 小于 100 μm。通过扫描电子显微镜（SEM）也确认了这些颗粒的大小，包括样品中存在潜在的纳米 TWPs。通过 SEM 进行的元素分析支持了由刹车片和道路磨损、道路铺装、道路灰尘、沥青和道路施工等来源的有机和无机颗粒团聚形成的复杂混合组成特征，这些颗粒是复杂的。由于科学文献中缺乏关于 TWPs 化学鉴定和定量分析的知识，因此本研究为高速公路雨水径流中这些新兴污染物提供了一种新颖的预处理和分析方法，具有重要意义。本研究结果突出表明，在真实环境样品中对 TWPs 进行鉴定和定量分析时，最有必要采用交叉验证技术，即 FTIR-ATR、Micro-FTIR、Pyr-GC/MS 和 SEM。
