College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China.
College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China; Institute of Eco-Environmental Research, Guangxi Academy of Sciences, Nanning, 530007, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangzhou, 510006, China.
Fish Shellfish Immunol. 2022 Jul;126:21-33. doi: 10.1016/j.fsi.2022.05.025. Epub 2022 May 19.
Nanoplastics (NPs) are good carriers of persistent organic pollutants (POPs) such as polybrominated diphenyl ethers (PBDEs), and can alter their bioavailability and toxic impacts to aquatic organisms. This study highlights the single and combined toxic effects of polystyrene nanoplastics (PS-NPs) and 2,2',4,4'-tetrabromodiphenyl ether (BDE-47, one of the dominant congeners of PBDEs) on zebrafish embryos after an exposure duration of up to 120 hpf. Results showed that PS-NPs and BDE-47 co-exposure exacerbated the morphological deformities in terms of pericardial edema, yolk sac edema and curved tail in zebrafish larvae. Compared to BDE-47 single exposure, the combined exposure caused lower survival rates, shorter body lengths, and accelerated spontaneous movements. Further, PS-NPs were quickly aggregated on the surface of the embryonic chorions covered almost the entire membrane at 12 and 48 hpf, and concentration dependent accumulation was also found in the brain, mouth, trunk, gills, heart, liver and gastrointestinal tract at the larval stages. During the recovery period (7 days), PS-NPs were released from all the organs, with the highest elimination from the gastrointestinal tract. Histopathological examination revealed that co-exposure caused greater damage to retinal structures, muscle fibers and cartilage tissues. Responses of hypothalamic-pituitary-thyroid axis (CRH, TSHβ, NIS, TTR, Dio2, TG, TRα and TRβ) and reproduction (Esr2 and Vtg1) related genes were also investigated, and results showed that the co-exposure induced more significant upregulated expressions of TSHβ, TG, Doi 2, and TRβ, compared to BDE-47 single exposure. In conclusion, co-exposure to NPs and BDE-47 exacerbated developmental and thyroid toxicity in zebrafish, generally elucidating the toxicological effects mediated by complex chemical interactions between NPs with POPs in the freshwater environment.
纳米塑料 (NPs) 是多溴二苯醚 (PBDEs) 等持久性有机污染物 (POPs) 的良好载体，可改变其在水生生物体内的生物利用度和毒性影响。本研究重点探讨了聚苯乙烯纳米塑料 (PS-NPs) 和 2,2',4,4'-四溴二苯醚 (BDE-47，一种 PBDEs 的主要同系物) 对斑马鱼胚胎的单一和联合毒性作用，暴露时间长达 120 hpf。结果表明，PS-NPs 和 BDE-47 共暴露加剧了斑马鱼幼虫心包水肿、卵黄囊水肿和尾巴弯曲等形态畸形。与 BDE-47 单一暴露相比，联合暴露导致存活率降低、体长缩短和自发运动加速。此外，PS-NPs 在 12 和 48 hpf 时迅速聚集在胚胎卵黄膜表面，几乎覆盖了整个膜，在幼虫阶段还发现了浓度依赖性的脑、口、躯干、鳃、心脏、肝脏和胃肠道积累。在恢复期 (7 天)，PS-NPs 从所有器官中释放出来，从胃肠道中消除的最多。组织病理学检查显示，共暴露对视网膜结构、肌肉纤维和软骨组织造成了更大的损伤。还研究了下丘脑-垂体-甲状腺轴 (CRH、TSHβ、NIS、TTR、Dio2、TG、TRα 和 TRβ) 和生殖 (Esr2 和 Vtg1) 相关基因的反应，结果表明，与 BDE-47 单一暴露相比，共暴露诱导了 TSHβ、TG、Doi2 和 TRβ 的更显著上调表达。总之，NP 和 BDE-47 的共暴露加剧了斑马鱼的发育和甲状腺毒性，通常阐明了淡水环境中 NP 与 POPs 之间复杂化学相互作用介导的毒理学效应。
