Microplastic risk assessment in surface waters: A case study in the Changjiang Estuary, China.

The rapid development of plastic industry has resulted in a series of environmental problems caused by microplastics originating from larger plastics. Microplastic pollution risk in surface waters of the Changjiang Estuary was explored based on risk assessment models. The average microplastic concentration was 23.1 ± 18.2 n/100 L. Shape, size, color and composition types of microplastics were examined. The risk assessment models were developed using data on both the concentration and chemical hazard of microplastic polymers. Assessment results indicated that polyvinyl chloride exhibited a critical concern for microplastic risk. Areas around aquaculture farms were regarded as "hotspots" of microplastic pollution due to the accumulation of microplastics and the presence of hazardous microplastic. This risk assessment of microplastics bridged gaps in understanding between field research and policy-making for surface waters. This research provides baseline data for assessing the environmental risk of microplastics in this growing area of research.