Evaluating the role of urban green infrastructure in combating traffic-related microplastic pollution

IF 8.2 1区环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES

Science of the Total Environment Pub Date : 2025-05-19 DOI:10.1016/j.scitotenv.2025.179688

Abdullah Khan , Valda Araminienė , Ieva Uogintė , Iveta Varnagirytė-Kabašinskienė , Valentinas Černiauskas , Valda Gudynaitė-Franckevičienė , Algis Džiugys , Lina Davulienė , Edgaras Misiulis , Mehri Davtalab , Steigvilė Byčenkienė

{"title":"Evaluating the role of urban green infrastructure in combating traffic-related microplastic pollution","authors":"Abdullah Khan , Valda Araminienė , Ieva Uogintė , Iveta Varnagirytė-Kabašinskienė , Valentinas Černiauskas , Valda Gudynaitė-Franckevičienė , Algis Džiugys , Lina Davulienė , Edgaras Misiulis , Mehri Davtalab , Steigvilė Byčenkienė","doi":"10.1016/j.scitotenv.2025.179688","DOIUrl":null,"url":null,"abstract":"<div><div>As cities grapple with the invisible threat of airborne microplastics (MPs), non-exhaust emissions, especially traffic-related MPs, contribute significantly to urban air pollution. While emission regulations have reduced exhaust pollutants, non-exhaust sources remain a significant challenge. Urban green infrastructure (UGI), valued for aesthetic and ecological functions, remains underexplored for MP mitigation. This study assesses the role of a <em>Thuja occidentalis</em> hedge in Kaunas, Lithuania, as a natural barrier against traffic-related MPs. Over a four-month seasonal campaign, passive deposition sampling was conducted at four distances from the street, with additional sampling in the hedge's absence for an experimental-control comparison. Optical microscopy revealed distinct size and shape distributions, while μ-FTIR spectroscopy confirmed dominant polymer compositions: PE (69.05 %) in spring, PIR (35.96 %) in winter, and ACRs (28.52 %) in summer. The highest average fragment concentration occurred in spring (98.25 %), while fibers peaked in winter (12.75 %). Black was dominant year-round, with the highest average in spring (55.35 %), followed by white in winter (42.16 %) and brown in spring (26.98 %). MPs in the 50–100 μm range were most abundant, reaching 55.26 % in spring. A similar trend appeared in vertical MP distribution. The most pronounced difference was noticed at (+1 m) behind the hedge, where MP concentration was 4.59 particles cm<sup>−2</sup> day<sup>−1</sup>, significantly lower than 9.2 particles cm<sup>−2</sup> day<sup>−1</sup> in the control. The hedge showed peak removal efficiencies in summer (64.5 % total MPs, 64.3 % fragments, 71.4 % fibers). The 50–100 μm range exhibited the highest efficiency, averaging 67.25 % with a seasonal high of 94.24 % in spring. Strong Mantel (<em>rm</em>) and Pearson's (<em>r</em>) correlations of very small MPs (<20 μm) at -1 m suggest a significant influence from tire wear, brake wear, and road dust resuspension. This study highlights Thuja hedge as an active defender against MP pollution, advocating for its strategic integration into urban design to enhance public health protection.</div></div>","PeriodicalId":422,"journal":{"name":"Science of the Total Environment","volume":"983 ","pages":"Article 179688"},"PeriodicalIF":8.2000,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Science of the Total Environment","FirstCategoryId":"93","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0048969725013294","RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}

引用次数: 0

Abstract

As cities grapple with the invisible threat of airborne microplastics (MPs), non-exhaust emissions, especially traffic-related MPs, contribute significantly to urban air pollution. While emission regulations have reduced exhaust pollutants, non-exhaust sources remain a significant challenge. Urban green infrastructure (UGI), valued for aesthetic and ecological functions, remains underexplored for MP mitigation. This study assesses the role of a Thuja occidentalis hedge in Kaunas, Lithuania, as a natural barrier against traffic-related MPs. Over a four-month seasonal campaign, passive deposition sampling was conducted at four distances from the street, with additional sampling in the hedge's absence for an experimental-control comparison. Optical microscopy revealed distinct size and shape distributions, while μ-FTIR spectroscopy confirmed dominant polymer compositions: PE (69.05 %) in spring, PIR (35.96 %) in winter, and ACRs (28.52 %) in summer. The highest average fragment concentration occurred in spring (98.25 %), while fibers peaked in winter (12.75 %). Black was dominant year-round, with the highest average in spring (55.35 %), followed by white in winter (42.16 %) and brown in spring (26.98 %). MPs in the 50–100 μm range were most abundant, reaching 55.26 % in spring. A similar trend appeared in vertical MP distribution. The most pronounced difference was noticed at (+1 m) behind the hedge, where MP concentration was 4.59 particles cm⁻² day⁻¹, significantly lower than 9.2 particles cm⁻² day⁻¹ in the control. The hedge showed peak removal efficiencies in summer (64.5 % total MPs, 64.3 % fragments, 71.4 % fibers). The 50–100 μm range exhibited the highest efficiency, averaging 67.25 % with a seasonal high of 94.24 % in spring. Strong Mantel (rm) and Pearson's (r) correlations of very small MPs (<20 μm) at -1 m suggest a significant influence from tire wear, brake wear, and road dust resuspension. This study highlights Thuja hedge as an active defender against MP pollution, advocating for its strategic integration into urban design to enhance public health protection.

查看原文本刊更多论文

评估城市绿色基础设施在对抗交通相关微塑料污染中的作用

随着城市努力应对空气中微塑料（MPs）的无形威胁，非废气排放，特别是与交通有关的MPs，对城市空气污染起着重要作用。虽然排放法规减少了废气污染物，但非废气源仍然是一个重大挑战。城市绿色基础设施（UGI）具有美学和生态功能的价值，但在缓解环境污染方面仍未得到充分探索。本研究评估了立陶宛考纳斯的西方树篱的作用，作为对抗交通相关MPs的天然屏障。在为期四个月的季节性活动中，在距离街道四个距离的地方进行被动沉积采样，并在没有树篱的情况下进行额外采样，以进行实验对照比较。光学显微镜观察到不同的尺寸和形状分布，μ-FTIR光谱证实了主要的聚合物组成：春季为PE(69.05%)，冬季为PIR(35.96%)，夏季为ACRs（28.52%）。平均碎片浓度在春季最高（98.25%），纤维浓度在冬季最高（12.75%）。全年以黑色为主，春季最高（55.35%），其次为冬季白色（42.16%）和春季棕色（26.98%）。MPs在50 ~ 100 μm范围内最为丰富，春季达到55.26%。在垂直MP分布中也出现了类似的趋势。在树篱后（+1 m）处发现了最明显的差异，其中MP浓度为4.59颗粒cm - 2 day - 1，显著低于对照组的9.2颗粒cm - 2 day - 1。在夏季，树篱的去除效率最高（总MPs为64.5%，碎片为64.3%，纤维为71.4%）。在50 ~ 100 μm范围内效率最高，平均为67.25%，春季最高为94.24%。非常小的MPs （<20 μm）在-1 m下的强Mantel （rm）和Pearson (r)相关性表明，轮胎磨损、制动磨损和道路粉尘重悬浮对车辆的影响很大。本研究强调了Thuja树篱作为MP污染的积极捍卫者，倡导将其战略性地融入城市设计中，以增强公共健康保护。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Science of the Total Environment 环境科学-环境科学

CiteScore

17.60

自引率

10.20%

发文量

8726

审稿时长

2.4 months

期刊介绍： The Science of the Total Environment is an international journal dedicated to scientific research on the environment and its interaction with humanity. It covers a wide range of disciplines and seeks to publish innovative, hypothesis-driven, and impactful research that explores the entire environment, including the atmosphere, lithosphere, hydrosphere, biosphere, and anthroposphere. The journal's updated Aims & Scope emphasizes the importance of interdisciplinary environmental research with broad impact. Priority is given to studies that advance fundamental understanding and explore the interconnectedness of multiple environmental spheres. Field studies are preferred, while laboratory experiments must demonstrate significant methodological advancements or mechanistic insights with direct relevance to the environment.