School of Biosciences, The University of Melbourne, Parkville, 3010, Victoria, Australia; State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China.
School of Biosciences, The University of Melbourne, Parkville, 3010, Victoria, Australia.
Chemosphere. 2020 Aug;252:126567. doi: 10.1016/j.chemosphere.2020.126567. Epub 2020 Mar 27.
Microplastic pollution is an important issue for environmental management as their ubiquity in marine and freshwaters has been confirmed. Pollution sources are key to understanding how microplastics travel from land to open oceans. Given that information regarding microplastic transport from diffuse sources is limiting, we conducted a study on roadside dust from rural and urban Victoria, Australia, over two seasons. Any deposited fugitive dust and particulate matter may also be present in our samples. The average microplastic abundance over two seasons ranged from 20.6 to 529.3 items/kg (dry weight based), with a predominant portion of fibers and items less than 1 mm. Polyester and polypropylene were the dominant polymer types (26%) while cotton and cellulose were the most common non-plastic items (27%). Sampling sites displayed consistent microplastic abundances over time and shared similar patterns in size, shape and polymer composition. Multiple correlation and principal component analysis suggest that urbanization and rainfall are important influences to roadside microplastic accumulation. The observed microplastic hotspots were generally located within close vicinity of areas where urban intensive land use and regional population sizes are high. Microplastics accumulated on roads and road verges during periods of dry weather and were flushed away during heavy storms while the corresponding trigger value was unknown. Monitoring roadside dust can be considered as an initial and cost-effective screening of microplastic pollution in urban areas. Further efforts should be made to optimize the methodologies and we advocate prolonged sampling schemes for roadside dust monitoring.
微塑料污染是环境管理的一个重要问题，因为它们在海洋和淡水中的普遍存在已经得到证实。污染来源是了解微塑料如何从陆地传播到开阔海洋的关键。鉴于有关从弥散源传播的微塑料的信息有限，我们在澳大利亚维多利亚州的农村和城市地区进行了一项关于路边灰尘的研究，历时两个季节。任何沉积的逸散性灰尘和颗粒物也可能存在于我们的样本中。两个季节的平均微塑料丰度范围为 20.6 至 529.3 个/千克（基于干重），主要部分为纤维和小于 1 毫米的物品。聚酯和聚丙烯是主要的聚合物类型（26%），而棉花和纤维素是最常见的非塑料物品（27%）。采样点在时间上显示出一致的微塑料丰度，并且在大小、形状和聚合物组成方面具有相似的模式。多元相关和主成分分析表明，城市化和降雨对路边微塑料积累有重要影响。观察到的微塑料热点通常位于城市密集土地利用和区域人口密度高的区域附近。微塑料在干燥天气期间在道路和路缘上积累，并在暴雨期间被冲走，而相应的触发值未知。监测路边灰尘可以被视为城市地区微塑料污染的初始和具有成本效益的筛选。应进一步努力优化方法，我们提倡延长路边灰尘监测的采样方案。
