Temporal and Spatial Distribution of Microplastics in a Coastal Region of the Pearl River Estuary, China

This study conducted an analysis of microplastics (MPs) pollution in a coastal region of the Pearl River Estuary (PRE) in the South China Sea. The results show that the abundance of MPs during the rainy season reached 545.5 particles m−3, which was 1.85-fold higher than during the dry season. The spatial distribution of MPs also varied offshore in the following order: the river > estuary > sea. The average abundance of MPs in the river was 1.17-fold higher than that of the estuary and 4.65-fold higher than that of the marine environment. There were large amounts of gray, white, and green MPs, and about 53.5–73.9% of the MPs were less than 0.5 mm. The main forms of MPs were fibers, granules, fragments, and films. MPs composed of polyethylene accounted for 35.7–38.8%. PCA analysis showed that MPs carried by the river were an important source of MP pollution in the coastal waters.