0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Environmental Sources Sign in to save

Occurrence and characteristics of microplastics in the Haihe River: An investigation of a seagoing river flowing through a megacity in northern China

Environmental Pollution 2020 171 citations ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count.
Yang Liu, JiaoDi Zhang, ChuanYang Cai, Yong He, Liyuan Chen, Xiong Xiong, Huijing Huang, Shu Tao, Wenxin Liu

Summary

Microplastics were found throughout the Haihe River in northern China at concentrations of 0.69 to 74.95 items per square meter, with fibers dominant and polyethylene and polypropylene the most common polymers. Weathering features including scratches and micropores on particle surfaces confirmed long-term environmental exposure before collection.

Polymers
Study Type Environmental

Freshwater systems serve as important sources and transportation routes for marine microplastic pollution, and inadequate attention has been paid to this situation. Data on microplastic pollution of typical seagoing rivers in northern China are lacking. In the current study, we investigated the distribution and characteristics of microplastics in the main stream of the Haihe River, which flows through a metropolis with a high population density and level of industrialization and then flows into the Bohai Sea. The microplastic samples were collected by manta trawls with pore sizes of 333 μm, and the microplastic concentrations ranged from 0.69 to 74.95 items/m. Fibers dominated in the surface water of the Haihe River; their shapes that were categorized as fibers, film, foam, fragments, and spheres, and contributed 17.4-86.7% of the total microplastics studied. The size distribution of the microplastics was concentrated in a range of 100-1000 μm, with 54.7% of the total sizes corresponding to the 333-μm trawl. Micro-Fourier transform infrared (μ-FT-IR) spectra showed that the main components were polyethylene, poly(ethylene-propylene) copolymer, and polypropylene. Scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) measurements revealed scratches, micropores, and cracks on the surfaces of the microplastics due to mechanical friction, chemical oxidation and degradation processes. The results of this study confirmed the high abundance and high diversity of microplastics in an urban river and indicated appreciable impacts from point-source inputs on the microplastic pollution, such as effluents from wastewater treatment plants (WWTPs).

Share this paper