Current status and cause analysis of microplastic pollution in sea areas in China

As a new type of pollutants in the marine environment, microplastics have attracted increasing attention from scientific researchers and environmental protection workers in China and abroad. However, for the microplastic pollution in sea areas in China, there are a very limited number of studies on its current status and few reviews of research on the microplastics. This paper reviews the surveys and researches of microplastics in the Bohai Sea, the Yellow Sea, the East China Sea, the South China Sea, and main estuaries in China carried out in recent years and proposes an outlook for future work, aiming to provide research suggestions and solutions for ecological protection against microplastic pollution in sea areas in China. Previous studies have shown that microplastics are widely distributed in water bodies and sediments in sea areas and major estuaries in China. The Pearl River Estuary, in the South China Sea suffers the most serious microplastic pollution, followed by the Bohai Sea. In contrast, the microplastic pollution in the Yellow Sea and the East China Sea is comparatively slight. Microplastics in sea areas in China are mainly fibrous and are concentrated in offshore areas with developed industry and a dense population (especially around estuaries and bays). In addition, they are widely affected by human activities, such as shipping, aquaculture, industry, and sewage discharge. Here the authors suggest unifying measurement units and research methods and developing related standard systems to carry out researches related to microplastics. Furthermore, this paper also suggests further deepening researches on both the source-sink process of microplastics and nanoscale microplastics while enhancing the development and implementation of related policies, aiming to promote researches and control of microplastics in sea areas in China.