Department of Biology & Center for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193, Aveiro, Portugal.
Department of Mechanical Engineering & Center for Mechanical Technology and Automation (TEMA), University of Aveiro, 3810-193, Aveiro, Portugal.
Sci Rep. 2018 Jun 5;8(1):8571. doi: 10.1038/s41598-018-26729-2.
Salinity shifts in estuarine and coastal areas are becoming a topic of concern and are one of the main factors influencing nanoparticles behaviour in the environment. For this reason, the impacts of multi-walled carbon nanotubes (MWCNTs) under different seawater salinity conditions were evaluated on the common ragworm Hediste diversicolor, a polychaete species widely used as bioindicator of estuarine environmental quality. An innovative method to assess the presence of MWCNT aggregates in the sediments was used for the first time. Biomarkers approach was used to evaluate the metabolic capacity, oxidative status and neurotoxicity of polychaetes after long-term exposure. The results revealed an alteration of energy-related responses in contaminated polychaetes under both salinity conditions, resulting in an increase of metabolism and expenditure of their energy reserves (lower glycogen and protein contents). Moreover, a concentration-dependent toxicity (higher lipid peroxidation, lower ratio between reduced and oxidized glutathione and activation of antioxidant defences and biotransformation mechanisms) was observed in H. diversicolor, especially when exposed to low salinity. Additionally, neurotoxicity was observed by inhibition of Cholinesterases activity in organisms exposed to MWCNTs at both salinities.
盐度变化在河口和沿海地区正成为一个关注的话题，也是影响环境中纳米颗粒行为的主要因素之一。因此，评估了多壁碳纳米管（MWCNTs）在不同海水盐度条件下对广泛用作河口环境质量生物标志物的多毛类动物普通沙蚕（Hediste diversicolor）的影响。首次使用了一种创新的方法来评估沉积物中 MWCNT 聚集体的存在。生物标志物方法用于评估多毛类动物在长期暴露后的代谢能力、氧化状态和神经毒性。结果表明，在两种盐度条件下，受污染的多毛类动物的能量相关反应发生了改变，导致代谢增加和能量储备消耗（糖原和蛋白质含量降低）。此外，在 H. diversicolor 中观察到浓度依赖性毒性（更高的脂质过氧化、还原型和氧化型谷胱甘肽之间的比例降低以及抗氧化防御和生物转化机制的激活），尤其是在低盐度下。此外，在两种盐度下暴露于 MWCNTs 的生物体中，乙酰胆碱酯酶活性的抑制表明存在神经毒性。
