Institute of Environmental Assessment and Water Research (IDAEA-CSIC), C. Jordi Girona, 18-26, 08034, Barcelona (Spain).
ISGlobal, C. Doctor Aiguader, 88, 08003, Barcelona (Spain); Universitat Pompeu Fabra (UPF), Pl. de la Mercè, 10-12, 08002, Barcelona (Spain); CIBER Epidemiología y Salud Pública (CIBERESP), Av. Monforte de Lemos, 3-5, 28029, Madrid (Spain).
Water Res. 2022 Jul 15;220:118645. doi: 10.1016/j.watres.2022.118645. Epub 2022 May 22.
Microplastics (MPLs) are emerging persistent pollutants affecting drinking water systems, and different studies have reported their presence in tap water. However, most of the work has a focus on particles in the 100-5 µm range. Here, a workflow to identify and quantify polymers of micro and nanoplastics (MNPLs), with sizes from 0.7 to 20 µm in tap water, is presented. The analytical method consisted of water fractionated filtration followed by toluene ultrasonic-assisted extraction and size-exclusion chromatography, using an advanced polymer chromatography column coupled to high-resolution mass spectrometry with atmospheric pressure photoionization source with negative and positive ionization conditions (HPLC(APC)-APPI(±)-HRMS) and normal phase chromatography HILIC LUNA® column and electrospray ionisation source in positive and negative mode (HPLC(HILIC)-ESI(±)-HRMS). The acquisition was performed in full scan mode, and the subsequent tentative identification of MNPLs polymers has been based on increasing the confirmation level, including the characterisation of monomers by using Kendrick Mass Defect (KMD) analysis, and confirmation and quantification using standards. This approach was applied to assess MNPLs in tap water samples of the Barcelona Metropolitan Area (BMA), that were collected from August to October 2020 from home taps of volunteers distributed in the 42 postal codes of the BMA. Polyethylene (PE), polypropylene (PP), polyisoprene (PI), polybutadiene (PBD), polystyrene (PS), polyamide (PA), and polydimethylsiloxanes (PDMS) were identified. PE, PP, and PA were the most highly detected polymers, and PI and PBD were found at the highest concentrations (9,143 and 1,897 ng/L, respectively). A principal component analysis (PCA) was conducted to assess differences in MNPLs occurrence in drinking water, that was provided from the two drinking water treatment plants (DWTPs) suppliers. Results showed that no significant differences (at 95% confidence level) were established between the drinking water supplies to the different areas of the BMA.
微塑料（MPLs）是新兴的持久性污染物，影响饮用水系统，不同的研究已经报道了它们在自来水中的存在。然而，大多数工作都集中在 100-5μm 范围内的颗粒上。在这里，提出了一种用于识别和量化微纳米塑料（MNPLs）聚合物的工作流程，这些聚合物的尺寸在 0.7 到 20μm 之间，存在于自来水中。该分析方法包括水分级过滤，然后用甲苯超声辅助提取和尺寸排阻色谱法，使用先进的聚合物色谱柱与大气压光电离源结合，带有正负离子化条件（HPLC(APC)-APPI(±)-HRMS）和正相色谱 HILIC LUNA®柱和电喷雾电离源在正负模式下（HPLC(HILIC)-ESI(±)-HRMS）。采集是在全扫描模式下进行的，随后对 MNPLs 聚合物进行了初步鉴定，包括通过使用 Kendrick 质量缺陷（KMD）分析对单体进行特征描述，以及使用标准进行确认和定量。该方法应用于评估 2020 年 8 月至 10 月间从巴塞罗那大都市区（BMA）志愿者家中水龙头收集的自来水中的 MNPLs。鉴定出了聚乙烯（PE）、聚丙烯（PP）、聚异戊二烯（PI）、聚丁二烯（PBD）、聚苯乙烯（PS）、聚酰胺（PA）和聚二甲基硅氧烷（PDMS）。PE、PP 和 PA 是检测到的最主要聚合物，PI 和 PBD 的浓度最高（分别为 9143 和 1897ng/L）。进行了主成分分析（PCA），以评估饮用水中 MNPLs 存在的差异，这些饮用水来自两个饮用水处理厂（DWTPs）供应商。结果表明，BMA 不同地区的饮用水供应之间没有建立显著差异（置信水平为 95%）。
