Department of Civil Engineering, Aalborg University, Thomas Manns Vej 23, 9220 Aalborg, Denmark.
Department of Civil Engineering, Aalborg University, Thomas Manns Vej 23, 9220 Aalborg, Denmark.
Environ Pollut. 2019 Dec;255(Pt 2):113335. doi: 10.1016/j.envpol.2019.113335. Epub 2019 Sep 30.
Urban and highway surfaces discharge polluted runoff during storm events. To mitigate environmental risks, stormwater retention ponds are commonly constructed to treat the runoff water. This study is the first to quantify the retention of microplastics in the sediments of such ponds. It applied state-of-art FTIR-methods to analyse the composition, size, shape, and mass of microplastics in the range 10-2000 μm. Seven ponds serving four land uses were investigated, and the results are related to catchment characteristics, sediment organic matter content, and hydraulic loading. We have not found a correlation between the microplastics abundance, polymer composition, size distribution and the land use in the catchment, as well as the sediment organic matter content. Both the highest (127,986 items kg; 28,732 μg kg) and the lowest (1511 items kg; 115 μg kg) accumulation of microplastics were found in the sediments of ponds serving industrial areas. There was, however, a correlation to the hydraulic loading of the ponds, where the sediments of the highest-loaded ponds held the most microplastics. This study shows that sediments in stormwater retention ponds can trap some of the microplastics and prevent them from being transported downstream. These systems need to be considered when assessing the fate of microplastics from urban and highway areas.
城市和高速公路表面在暴雨事件中排放受污染的径流。为了减轻环境风险，通常会建造雨水滞留池来处理径流。本研究首次定量研究了这些池塘中沉积物对微塑料的截留作用。它采用了最先进的 FTIR 方法来分析 10-2000μm 范围内微塑料的组成、大小、形状和质量。研究了四个土地利用类型的七个池塘，结果与集水区特征、沉积物有机质含量和水力负荷有关。我们没有发现微塑料丰度、聚合物组成、粒径分布与集水区的土地利用以及沉积物有机质含量之间存在相关性。在服务于工业区的池塘沉积物中，微塑料的积累量最高（127986 个项 kg；28732μgkg）和最低（1511 个项 kg；115μgkg）。然而，这与池塘的水力负荷有关，高负荷池塘的沉积物中含有最多的微塑料。本研究表明，雨水滞留池中的沉积物可以截留一些微塑料，防止它们被输送到下游。在评估城市和高速公路地区的微塑料命运时，需要考虑这些系统。
