Nantes Université, Institut des Substances et Organismes de la Mer, ISOMer, UR 2160, Nantes F44000, France.
Aix Marseille University, CNRS, LCE, Marseille, France.
Aquat Toxicol. 2023 Sep;262:106669. doi: 10.1016/j.aquatox.2023.106669. Epub 2023 Aug 25.
The mussels are species with high socio-economic weights and are often used as bioindicators of biological and chemical contamination. In the field and aquaculture, they can intake microplastics during filter-feeding, and the microplastics can have a negative impact on their health, even at low concentrations. The effects of microplastics have yet to be fully examined on the blue mussel (Mytilus edulis), considering the factors of ageing and sorption of some polyaromatic hydrocarbons (PAHs), ubiquitous environmental contaminants. In this work, 5 different exposure conditions were studied: pristine microplastics, microplastics aged for 1000 days under UV radiation, microplastics sorbing PAHs, as well as microplastics both aged and sorbing PAHs, in parallel to controls. The microplastic changes after ageing were studied with spectroscopic and chromatographic methods. Then, 8-day laboratory exposures of mussels at 10 µg/L of microplastics were performed. The oxidative stress, as well as neurotoxic and immunological responses of M. edulis, were measured using a battery of biomarkers (catalase/CAT, superoxide dismutase/SOD, glutathione S-transferases/GST, acetylcholinesterase/AChE) in 3 different organs (digestive gland, gills and mantle), and acid phosphatase in hemolymph. Then, a study of lipid impairments on the digestive gland was performed through the use of lipidomic tools. No significant difference of oxidative stress activity was observed for all the tissues of mussels exposed to pristine microplastics at 10 µg/L, compared to controls. The ageing and the PAH soption onto microplastics were influencing factors of the oxydative stress in mussels with increased CAT activities in the digestive glands and decreased SOD activities in the mantles. The neurotoxicity was highlighted by higher AChE activities measured in the mantle of mussels exposed to all the microplastic treatments, compared to controls. Concerning lipidomics, no compound was determined as a biomarker of microplastic exposure. The study demonstrated a low toxicity of microplastics at environmental relevant concentration with a 8-day exposure and using the chosen biomarkers. However, some microplastic changes seemed to lead to specific effects on mussels.
贻贝是具有高社会经济重要性的物种，通常被用作生物和化学污染的生物标志物。在野外和水产养殖中，它们在滤食过程中可能会摄入微塑料，而微塑料即使在低浓度下也会对它们的健康产生负面影响。考虑到老化因素和一些多环芳烃（PAHs）的吸附，微塑料对贻贝（Mytilus edulis）的影响尚未得到充分研究。PAHs 是普遍存在的环境污染物。在这项工作中，研究了 5 种不同的暴露条件：原始微塑料、在紫外线辐射下老化 1000 天的微塑料、吸附多环芳烃的微塑料，以及同时老化和吸附多环芳烃的微塑料，同时设置对照组。用光谱和色谱方法研究了老化后微塑料的变化。然后，在 10 µg/L 的微塑料浓度下进行了为期 8 天的贻贝实验室暴露实验。使用一系列生物标志物（过氧化氢酶/CAT、超氧化物歧化酶/SOD、谷胱甘肽 S-转移酶/GST、乙酰胆碱酯酶/AChE）在 3 个不同器官（消化腺、鳃和套膜）和血淋巴中的酸磷酸酶，测量贻贝的氧化应激、神经毒性和免疫反应。然后，通过使用脂质组学工具研究了消化腺中脂质损伤。与对照组相比，在 10 µg/L 的原始微塑料浓度下，暴露于原始微塑料的贻贝所有组织的氧化应激活性均无显著差异。老化和 PAH 对微塑料的吸附是贻贝氧化应激的影响因素，表现为消化腺中 CAT 活性增加和套膜中 SOD 活性降低。所有微塑料处理组贻贝套膜中 AChE 活性升高，表明其神经毒性。关于脂质组学，没有一种化合物被确定为微塑料暴露的生物标志物。该研究表明，在环境相关浓度下，贻贝在 8 天暴露于微塑料后，使用所选生物标志物，其毒性较低。然而，一些微塑料的变化似乎对贻贝产生了特定的影响。
