Key Laboratory for Ecological Environment in Coastal Areas, Ministry of Ecology and Environment, National Marine Environmental Monitoring Center, Dalian 116023, China.
Key Laboratory for Ecological Environment in Coastal Areas, Ministry of Ecology and Environment, National Marine Environmental Monitoring Center, Dalian 116023, China.
Aquat Toxicol. 2023 Mar;256:106430. doi: 10.1016/j.aquatox.2023.106430. Epub 2023 Feb 18.
As two major ubiquitous pollutants, microplastics (MPs) and polycyclic aromatic hydrocarbons (PAHs) coexist in the marine environment. However, the role of MPs in altering the toxicity of PAHs to marine organisms is poorly understood. We therefore investigated the accumulation and toxicity of benzo[a]pyrene (B[a]P, 0.4 nM), in the marine mussel Mytilus galloprovincialis over a 4-day of exposure with or without the presence of 10 μm polystyrene microplastics (PS MPs) (10 particles/mL). The presence of PS MPs significantly decreased B[a]P accumulation in soft tissues of M. galloprovincialis by approximately 6.7%. Single exposure of PS MPs or B[a]P decreased the mean epithelial thickness (MET) of digestive tubules and enhanced reactive oxygen species (ROS) levels in haemolymph, while upon co-exposure the adverse impacts were alleviated. Real-time q-PCR results showed that most selected genes involved in stress response (FKBP, HSP90), immune (MyD88a, NF-κB) and detoxification (CYP4Y1) were induced for both single exposure and co-exposure. The co-presence of PS MPs down-regulated the mRNA expression of NF-κB in gills compared with of B[a]P alone. The uptake and toxicity reductions of B[a]P might result from the decrease of its bioavailable concentrations caused by the adsorption of B[a]P by PS MPs and the strong affinity of B[a]P to PS MPs. Adverse outcomes for the co-existence of marine emerging pollutants under long-term conditions remain to be further validated.
作为两种主要的普遍存在的污染物，微塑料（MPs）和多环芳烃（PAHs）共存于海洋环境中。然而，MPs 改变 PAHs 对海洋生物毒性的作用尚不清楚。因此，我们研究了在 4 天的暴露过程中，有或没有 10μm 聚苯乙烯微塑料（PS MPs）（10 个/毫升）存在的情况下，海洋贻贝贻贝中苯并[a]芘（B[a]P，0.4 nM）的积累和毒性。PS MPs 的存在使贻贝软组织中 B[a]P 的积累减少了约 6.7%。PS MPs 或 B[a]P 的单次暴露降低了消化管的平均上皮厚度（MET），并增加了血液中的活性氧（ROS）水平，而在共暴露时，这些不利影响得到了缓解。实时 q-PCR 结果表明，大多数参与应激反应（FKBP、HSP90）、免疫（MyD88a、NF-κB）和解毒（CYP4Y1）的选定基因在单一暴露和共暴露时都被诱导。与单独 B[a]P 暴露相比，PS MPs 的共存使鳃中 NF-κB 的 mRNA 表达下调。PS MPs 对 B[a]P 的吸附作用和 B[a]P 与 PS MPs 的强亲和力可能导致其生物可利用浓度降低，从而导致 B[a]P 的摄取和毒性降低。在长期条件下，海洋新兴污染物共存的不良后果仍有待进一步验证。
