Sedimentary record of microplastics in coastal wetland, eastern China

Microplastic (MP) dynamics can reflect history of plastic production and waste management in nearby areas. However, the stratigraphy of MPs in coastal wetlands and their link to policy and economic pattern changes are currently unclear. Here, MP stratigraphic records in sediment core from coastal wetlands in Yancheng, China, were used to reconstruct plastic pollution history. Neural network models simulated how policy intervention and economic development affected MP accumulation over time. We showed that MP abundance curves with boundaries from 1920 to 2019 had four stages. MP growth slowed or even decreased in the mid-to-late 1980s due to improved waste management and wastewater treatment since the late 1980s. Human activities were the primary factor affecting MP abundance and shape, followed by sediment properties. We predict that the environmental impact of MPs will continue to increase in the next decade. Current plastic policy measures focus on predictable waste emissions, but hidden sources like clothing fibers and tire wear that significantly contribute to MP pollution require further attention.