Occurrence and pollution characteristics of microplastics in surface water of the Manas River Basin, China

Microplastics, as a new type of pollutant, are widely found in various environmental media, and their effects on organisms are of great concern to society. However, research on the characteristics of microplastic pollution in inland rivers in China is still rare. The Manas River, which is located in the interior of Northeast China, was selected as the research object. The occurrence and pollution characteristics of microplastics in the surface water of the river were explored. The range of abundance of microplastics in the Manas River Basin was 21 ± 3-49 ± 3 items/L. Fibrous microplastics were dominant in all sites (88.0%); their size was mainly distributed between 0.1 and 1.0 mm (82.6%), and white and black were the dominant colours (82.9%). In addition, the size range of flaky-type microplastics were investigated in this study, which was principally between 2.5 × 10³-9.0 × 10⁴ μm² (84.5%). Infrared spectral analysis revealed that most of the selected particles were identified as microplastics, and polymer types of microplastics were dominated by polypropylene and polyethylene terephthalate (48.3%). This study can be used as a reference to better understand the contamination features of microplastics in inland rivers.