文献名： The influence of nanoplastics on the toxic effects, bioaccumulation, biodegradation and enantioselectivity of ibuprofen in freshwater algae Chlorella pyrenoidosa

作者： Fang Wang^a， Bin Wang^ab， Han Qu^ac， Wenxing Zhao^a， Lei Duan^a， Yizhe Zhang^a， Yitong Zhou^a， Gang Yu^ab

^a School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC), Tsinghua University, Beijing, 100084, PR China

^b Research Institute for Environmental Innovation (Suzhou), Tsinghua, Building 16, 101 Business Park, No, 158 Jinfeng Road, New District, Suzhou, 215163, China

^c Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ, 85712, United States

摘要：Plastic pollution has become a pressing issue due to its persistence in the environment. Smaller plastics are more easily ingested, potentially exerting greater influences on organisms. In this study, the effects of polystyrene nanoplastics (NP) on the toxic effects, bioaccumulation, biodegradation and enantioselectivity of ibuprofen (IBU) in algae Chlorella pyrenoidosa were explored. The influences on the growth rate, chlorophyll a, total antioxidant capacity (T-AOC), reactive oxygen species (ROS) and lipid peroxidation (MDA) were evaluated after 96 h of exposure to a combination of polystryene NP (1 mg L⁻¹) and IBU (5–100 mg L⁻¹). The results indicated that the inhibitory effect of IBU on C. pyrenoidosa growth was alleviated in the presence of NP. For instance, the 96 h-IC₅₀ value for rac-IBU in the treatment lacking NP was 45.7 mg L⁻¹, and the corresponding value in the treatment containing NP was 63.9 mg L⁻¹. The co-exposure of NP led to a significant enhancement of T-AOC and slight reduction of ROS and MDA compared with the individual exposure (IBU) group, suggesting a decreased oxidative stress. In addition, treatment with NP led to a decreased bioaccumulation and accelerated biodegradation of IBU in C. pyrenoidosa and enhanced removal in the medium. The enantioselective toxicity, bioaccumulation and biodegradation of IBU were observed both in the absence and presence of NP. S-IBU exhibited a greater toxicity, and R-IBU was preferentially accumulated and degraded in C. pyrenoidosa. No interconversion of the two enantiomers occurred regardless of the presence of NP. This consequence implied that the influence of coexistent NP should be considered in the environmental risk assessment of pharmaceuticals and personal care products in aquatic environments.