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, Shandong Province, Qingdao, 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, Shandong Province, Qingdao, PR China.
Environ Res. 2022 Apr 15;206:112558. doi: 10.1016/j.envres.2021.112558. Epub 2021 Dec 18.
C9 aromatics - benzene hydrocarbon containing nine carbon atoms among - leakage accident has caused serious damage to the marine ecology near Quangang District, Fujian Province, China. The ecological restoration of the accident sea area is basically realized through natural attenuation. To determine whether the natural attenuation of C9 aromatics in the marine environment will generate highly toxic intermediates, and thus cause more serious harm to marine ecology, the intermediates of C9 aromatics (n-propylbenzene, isopropylbenzene, 2-ethyltoluene, 3-ethyltoluene, 4-ethyltoluene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, and indene) in the process of natural attenuation were studied under the marine conditions simulated by a microcosm. The acute toxic effects of 12 intermediates with longer residual time on Phaeodactylum tricornutum were also ascertained. Twenty natural attenuation intermediates of C9 aromatics were identified. These products primarily include the derivatives of phenols, aromatic alcohols, aromatic aldehydes, aromatic ketones, and aromatic acids, as well as an aromatic lactone compound. No intermediates of 1,3,5-trimethylbenzene and indene during the attenuation process were determined. The indirect photooxidation initiated by hydroxyl radical might play an essential role in the formation of intermediates of C9 aromatic. Based on the 96-h EC values for P. tricornutum, the toxicity of the 12 intermediates, in descending order, was: 4-ethylphenol, 2-methylacetophenone, 2,3-dimethylbenzyl alcohol, 4-methylacetophenone, 3-methylacetophenone, 1-phenyl-1-propanol, 1-(2-methylphenyl) ethanol, 2-phenyl-2-propanol, 3,4-dimethylbenzoic acid, 2,4-dimethylbenzoic acid, 2,5-dimethylbenzoic acid, then 4-tolylacetic acid. The 96-h EC values of the intermediates of C9 aromatics to P. tricornutum ranged from 8.4 to 199.1 mg/L, which were lower than that of their corresponding parent compound. The findings provided essential fundamental insights for the assessment of marine environmental risk of C9 aromatics leakage accidents, and subsequent emergency disposal countermeasures.
C9 芳烃——苯环上含有九个碳原子的芳烃——泄漏事故对中国福建省泉港区的海洋生态造成了严重破坏。该事故海域的生态恢复基本通过自然衰减实现。为了确定 C9 芳烃在海洋环境中的自然衰减是否会产生剧毒中间体，从而对海洋生态造成更严重的危害，本研究在海洋微环境模拟条件下，研究了 C9 芳烃（正丙苯、异丙苯、2-乙基甲苯、3-乙基甲苯、4-乙基甲苯、1,2,3-三甲苯、1,2,4-三甲苯、1,3,5-三甲苯和茚）在自然衰减过程中的中间体。还确定了 12 种具有较长残留时间的中间体对三角褐指藻的急性毒性作用。鉴定出 20 种 C9 芳烃的自然衰减中间体。这些产物主要包括酚类、芳香醇类、芳香醛类、芳香酮类和芳香酸类，以及一种芳香内酯化合物。在衰减过程中未检测到 1,3,5-三甲苯和茚的中间体。由羟基引发的间接光氧化可能在 C9 芳烃中间体的形成中发挥重要作用。基于三角褐指藻 96-h EC 值，12 种中间体的毒性依次为：4-乙基苯酚、2-甲基苯乙酮、2,3-二甲基苄醇、4-甲基苯乙酮、3-甲基苯乙酮、1-苯基-1-丙醇、1-(2-甲基苯基)乙醇、2-苯基-2-丙醇、3,4-二甲基苯甲酸、2,4-二甲基苯甲酸、2,5-二甲基苯甲酸、4-甲苯乙酸。C9 芳烃中间体对三角褐指藻的 96-h EC 值范围为 8.4 至 199.1 mg/L，低于相应母体化合物。这些发现为评估 C9 芳烃泄漏事故对海洋环境的风险以及随后的紧急处理对策提供了重要的基础见解。
