Species sensitivity distributions of microplastics based on toxicity endpoints and particle characteristics:...

The prevalence of microplastics (MPs) in Tai Lake poses significant environmental concerns; however, research on MPs' ecological risk assessment is limited. To advance our understanding of MPs' toxicity in Tai Lake, species sensitivity distributions (SSDs) were used to evaluate how organisms respond to different MPs properties and endpoints in Tai Lake. A total of 102 data points were categorized and utilized in SSD estimation. It was found that the hazardous concentration for 5% of species (HC₅) for MPs is 237.98 (26.89-2.59 × 10³) particles/L in Tai Lake. In terms of endpoints, the HC₅ follows the descending order: reproduction 1.03 × 10³ (16.30-6.05 × 10³) > growth 153.36 (11.37-2.53 × 10³) > mortality 67.60 (4.55-4.29 × 10³) particles/L. It was found that fibers and polyvinyl chloride (PVC) exhibit the most adverse effects among the MPs' shapes and types assessed. Among size fractions, 100-1000 μm exhibited higher toxicity to Tai Lake biota compared to 1-10 and 10-100 μm. The ecological risk assessment suggested that the likelihood of ecological risk from MPs in Tai Lake is higher for fibers and PVC. Notably, fish species were identified as the most sensitive species in Tai Lake compared to crustaceans and mollusks. This research leads to a better insight into the physical characteristics and toxicity endpoints of MPs in determining their toxicity for estimating SSDs in aquatic environments. Moreover, it highlights the importance of implementing effective management strategies to address the negative impacts of MPs in Tai Lake.