Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao, Shandong Province, PR China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, Shandong Province, PR China.
Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao, Shandong Province, PR China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, Shandong Province, PR China.
Ecotoxicol Environ Saf. 2022 Jul 15;240:113686. doi: 10.1016/j.ecoenv.2022.113686. Epub 2022 May 27.
n-Butyl acrylate (nBA), a typical hazardous and noxious substance (HNS), is the largest-volume acrylate ester used to produce various types of polymers. With the increasing volume of nBA subject to maritime transportation, its accidental leakage poses a great risk to the marine organisms. Therefore, it is necessary to evaluate the ecological risk of nBA in marine environments. In this study, two species of marine microalgae, Skeletonema costatum and Phaeodactylum tricornutum, were used to explore the toxic effects of nBA based on their growth, pigment content, and oxidative stress. The growth of each species was significantly inhibited by nBA, showing a 96 h-EC value of 2.23 mg/L for P. tricornutum and 8.19 mg/L for S. costatum, respectively. Although chlorophylls a and c exerted a hormesis effect in P. tricornutum, contents of pigments generally decreased at high concentrations. In P. tricornutum, all detected antioxidants (reduced glutathione, GSH; superoxide dismutase, SOD; catalase, CAT; and glutathione peroxidase, GPx) were stimulated at concentrations ranging from 1.50 to 3.82 mg/L. However, these elevations were not enough to reduce the oxidative damage caused by nBA, because the content of malondialdehyde (MDA) increased continuously during 96-h exposure. For S. costatum, the activities of only two antioxidants (GSH and CAT) were enhanced, which is enough to prevent the MDA content from rising, even at higher concentrations of nBA (5-10 mg/L). The Integrated Biomarker Response Version 2 (IBR) index that combines responses of the above five oxidative stress biomarkers, was not only correlated positively with nBA concentration but could also indicate the occurrence of oxidative stress caused by acute concentration of nBA. These findings showed that P. tricornutum was sensitive to nBA compared to S. costatum, and the IBR index was an effective tool for evaluating ecotoxicological effects on marine microalgae due to nBA spills.
正丁酯（nBA）是一种典型的危险有害物质（HNS），是用于生产各种类型聚合物的最大体积丙烯酯。随着海上运输的 nBA 数量的增加，其意外泄漏对海洋生物构成了巨大的风险。因此，有必要评估 nBA 在海洋环境中的生态风险。在这项研究中，使用两种海洋微藻 Skeletonema costatum 和 Phaeodactylum tricornutum 来研究 nBA 基于其生长、色素含量和氧化应激对的毒性影响。两种藻的生长均受到 nBA 的显著抑制，P. tricornutum 的 96 h-EC 值为 2.23 mg/L，S. costatum 的 96 h-EC 值为 8.19 mg/L。尽管 P. tricornutum 中的叶绿素 a 和 c 表现出激素效应，但在高浓度下色素含量通常会降低。在 P. tricornutum 中，所有检测到的抗氧化剂（还原型谷胱甘肽、GSH；超氧化物歧化酶、SOD；过氧化氢酶、CAT；和谷胱甘肽过氧化物酶、GPx）在 1.50 至 3.82 mg/L 的浓度范围内均受到刺激。然而，这些升高不足以降低 nBA 造成的氧化损伤，因为在 96 小时暴露期间，丙二醛（MDA）的含量不断增加。对于 S. costatum，只有两种抗氧化剂（GSH 和 CAT）的活性增强，即使在更高浓度的 nBA（5-10 mg/L）下，也足以防止 MDA 含量上升。结合了上述五种氧化应激生物标志物反应的综合生物标志物反应第 2 版（IBR）指数不仅与 nBA 浓度呈正相关，而且还可以指示由 nBA 急性浓度引起的氧化应激的发生。这些发现表明，与 S. costatum 相比，P. tricornutum 对 nBA 更为敏感，IBR 指数是评估由于 nBA 泄漏对海洋微藻产生的生态毒性效应的有效工具。
