Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 97187 Luleå, Sweden.
Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 97187 Luleå, Sweden.
Sci Total Environ. 2022 Dec 10;851(Pt 2):158306. doi: 10.1016/j.scitotenv.2022.158306. Epub 2022 Aug 26.
The microplastics (MP) pollution has been receiving high attention in recent years, because of the massive amounts of plastics it contributes to the environment. Tyre wear and road wear particles (TWP and RWPs) were identified as major sources of MPs, but the observed data on these particles in urban snow deposits and snowmelt is scarce. To contribute to remediation of this situation, a study designed to quantify TWPs and RWPs in urban roadside snowbanks, and assess the MP occurrence in three size fractions, was conducted in the Luleå and Umeå municipalities in Northern Sweden. TWPs and RWPs were determined in three size fractions: 50-100 μm, 100-300 μm, and ≥300 μm, and their release from melting snow was investigated in the laboratory under controlled conditions. Among the MPs identified in snow and the associated snowmelt samples, a majority consisted of both types of particles (T&RWPs) with an average of 20,000 ± 48,000 number/L, whereas other MPs (fibres, fragments, flakes, and films of plastic) were much less plentiful with an average concentration of 24 ± 16 number/L. The largest proportion of T&RWPs was detected in the size fraction 50-100 μm (around 80%), and the smallest proportion was in the fraction ≥300 μm (about 2%). Of the T&RWPs, about 85% were black bitumen particles (RWPs), composed of bitumen, mineral material and polymer modifiers, and 15% were tyre wear particles (TWPs) composed of rubber. The laboratory snow melting experiments demonstrated that urban snow stored MPs, which were eventually released during snowmelt. The ultimate fate of released MPs would depend on snowmelt drainage; it may either drain away from the road pavement and infiltrate into the ground, or enter the road gutter and be conveyed to storm sewers discharging to the receiving waters.
近年来，由于微塑料（MP）对环境造成的大量污染，其受到了高度关注。轮胎磨损和道路磨损颗粒（TWP 和 RWPs）被确定为 MPs 的主要来源，但在城市积雪和融雪中观察到这些颗粒的数据却很少。为了改善这种情况，在瑞典北部的吕勒奥和于默奥市进行了一项研究，旨在量化城市路边雪堤中的 TWP 和 RWPs，并评估三种粒径的 MPs 出现情况。TWP 和 RWPs 被确定在三个粒径：50-100μm、100-300μm 和≥300μm，并在实验室控制条件下研究了它们从融雪中的释放情况。在所分析的雪和相关融雪样本中的 MPs 中，大多数由 T&RWPs 组成，平均浓度为 20000±48000 个/L，而其他 MPs（纤维、碎片、薄片和塑料膜）的浓度要低得多，平均浓度为 24±16 个/L。T&RWPs 的最大比例出现在 50-100μm 的粒径中（约 80%），最小比例出现在≥300μm 的粒径中（约 2%）。在 T&RWPs 中，约 85%为黑色沥青颗粒（RWPs），由沥青、矿物材料和聚合物改性剂组成，15%为轮胎磨损颗粒（TWPs），由橡胶组成。实验室融雪实验表明，城市积雪中储存的 MPs 最终会在融雪时释放出来。释放的 MPs 的最终命运将取决于融雪的排水情况；它可能会从道路路面排走并渗透到地下，或者进入道路排水沟并被输送到排放到受纳水体的雨水沟。
