基于稀土上转换纳米颗粒示踪的球形与纤维状微塑料在河口潮间带中的环境归趋与生物富集研究OA

Current ecological risk assessments of microplastics predominantly use spherical particles as models,paying insufficient attention to ubiquitous non-spherical microplastics,such as fibers.This oversight may lead to an underestimation of their migration and accumulation risks in benthic en-vironments.This study employed rare-earth upconversion nanoparticles(UCNPs)tracer technology,combined with ICP-MS quantification and time-gated imaging(TGI),to compare the environmental fate and bioaccumulation characteristics of spherical PS and fibrous PAN during a 30-day exposure period within a multi-trophic estuarine intertidal mesocosm.The results indicate that PAN rapidly set-tles and accumulates in sediments,reaching a concentration of(30.94±5.52)μg·g-1 after 30 days;in contrast,PS remains suspended in the water column for a longer period.The accumulation concen-tration of PS in the biofilmed leaves of eelgrass(Zostera asiatica)reached as high as(511.69±108.16)μg·g-1,with a BCF of 11 449.The concentration of PS in the digestive gland of Crassostrea gigas((15.26±1.12)μg·g-1)was significantly higher than the PAN concentration.In contrast,Rap-ana venosa and Sebastes schlegelii exhibited a higher tendency to accumulate PAN in the sedimentary phase,with the material primarily retained in metabolic organs such as the digestive gland and liver.This study demonstrates that the physical characteristics of microplastics,including density,mor-phology,and their derived effective hydrodynamic size,are critical factors regulating their environ-mental fate and biological exposure pathways,providing a scientific basis for the precise control and risk prediction of microplastic pollution in estuaries.