Zhou Shuang, Qian Wei, Ning Zigong, Zhu Xiaoshan
Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
Shenzhen Honglue Research Institute of Innovation Management, Shenzhen 518119, China.
Nanomaterials (Basel). 2021 Oct 19;11(10):2769. doi: 10.3390/nano11102769.
Leakage of metal oxide nanoparticles (MNPs) into marine environments is inevitable with the increasing use of MNPs. However, little is known about the effects of these lately emerged MNPs on the bioaccumulation and toxicity of pre-existing contaminants in marine biota. The current study therefore investigated the effects of two common MNPs, CuO nanoparticles (nCuO) and FeO nanoparticles (nFeO), on bioaccumulation and toxicity of arsenic (As) in green mussel . Newly introduced MNPs remarkably promoted the accumulation of As and disrupted the As distribution in mussels because of the strong adsorption of As onto MNPs. Moreover, MNPs enhanced the toxicity of As by disturbing osmoregulation in mussels, which could be supported by decreased activity of Na-K-ATPase and average weight loss of mussels after MNPs exposure. In addition, the enhanced toxicity of As in mussels might be due to that MNPs reduced the biotransformation efficiency of more toxic inorganic As to less toxic organic As, showing an inhibitory effect on As detoxifying process of mussels. This could be further demonstrated by the overproduction of reactive oxygen species (ROS), as implied by the rise in quantities of superoxide dismutase (SOD) and lipid peroxidation (LPO), and subsequently restraining the glutathione-S-transferases (GST) activity and glutathione (GSH) content in mussels. Taken together, this study elucidated that MNPs may elevate As bioaccumulation and limit As biotransformation in mussels, which would result in an enhanced ecotoxicity of As towards marine organisms.
随着金属氧化物纳米颗粒（MNPs）使用量的增加，其泄漏到海洋环境中不可避免。然而，对于这些新出现的MNPs对海洋生物群中已有污染物的生物累积和毒性的影响，人们知之甚少。因此，本研究调查了两种常见的MNPs，即氧化铜纳米颗粒（nCuO）和氧化亚铁纳米颗粒（nFeO）对绿贻贝中砷（As）生物累积和毒性的影响。新引入的MNPs显著促进了As的累积，并扰乱了贻贝中As的分布，这是因为As在MNPs上有强烈的吸附作用。此外，MNPs通过干扰贻贝的渗透调节增强了As的毒性，这可以从MNPs暴露后贻贝Na-K-ATP酶活性降低和平均体重减轻得到证实。此外，贻贝中As毒性增强可能是因为MNPs降低了毒性更强的无机As向毒性较弱的有机As的生物转化效率，对贻贝的As解毒过程产生了抑制作用。超氧化物歧化酶（SOD）数量增加和脂质过氧化（LPO）上升所暗示的活性氧（ROS）过量产生进一步证明了这一点，随后抑制了贻贝中谷胱甘肽-S-转移酶（GST）的活性和谷胱甘肽（GSH）的含量。综上所述，本研究阐明MNPs可能会提高贻贝中As的生物累积并限制As的生物转化，这将导致As对海洋生物的生态毒性增强。
