Distribution Characteristics of Microplastics in Bellamya aeruginosa in Typical Area of Poyang Lake

A large number of studies have revealed that aquatic organisms can ingest microplastics. However, little research has been done on the ingestion of microplastics by freshwater benthic organisms. This study investigated the distribution characteristics of microplastics in Bellamya aeruginosa sampled from Poyang Lake, the largest freshwater lake in China. Bellamya aeruginosa samples were collected from seven sites, which included five rivers flowing into Poyang Lake, a nature reserve, and a lake outlet. The microplastics in B. aeruginosa were separated by tissue digestion and identified by microscopy and infrared spectroscopy. The results showed that the abundance of microplastics in B. aeruginosa in the typical area of Poyang Lake ranged from (0.52±0.15) to (2.48±0.90) n•g-1. The microplastic abundance in B. aeruginosa from the Gan River on average contained more microplastics than those collected from the other estuary because the Gan River flows through the densely populated city of Nanchang and has a large catchment area, the amount of microplastics discharged into the Gan River. Samples from the Nanjishan Wetland had the lowest average amount of microplastics. The microplastics in the B. aeruginosa samples were mainly fibers with a particle size of less than 1 mm, probably because small fiber particles are more likely to adhere. The abundance of microplastics in the gut of B. aeruginosa was higher than that in the muscle. Ingestion and adhesion may be two important pathways by which microplastics enter B. aeruginosa. This study suggests that human activities are an important factor affecting the abundance of microplastics in B. aeruginosa, thus demonstrating that effective protection can control microplastic pollution. The investigation of microplastics in benthic animals is helpful to comprehensively understand the ecological risks of microplastic pollution. © 2022, Science Press. All right reserved.