Jonker Michiel T O, Brils Jos M, Sinke Anja J C, Murk Albertinka J, Koelmans Albert A
Aquatic Ecology and Water Quality Management Group, Wageningen University, P.O. Box 8080, 6700 DD Wageningen, The Netherlands.
Environ Toxicol Chem. 2006 May;25(5):1345-53. doi: 10.1897/05-296r.1.
Many sediments are contaminated with mixtures of oil residues and polycyclic aromatic hydrocarbons (PAHs), but little is known about the toxicity of such mixtures to sediment-dwelling organisms and the change in toxicity on weathering. In the present study, we investigated the effects of a seminatural, two-year weathering period on PAH/oil chemistry and toxicity in a marine sediment that had been spiked with three different oils (a gas oil, a lubricating oil, and a crude oil; all tested at five concentrations). Toxicity of bioavailable, pore water-accommodated oil/PAH fractions was quantified using a bacterial (Vibrio fischeri) assay and the in vitro chemical-activated luciferase expression assay (DR-CALUX; using conditions to detect PAHs). Results of chemical analyses pointed to (microbial) degradation of all three oils: Sediment oxygen demand during weathering increased with increasing oil concentration, total oil concentrations decreased to between 17 and 29% of initial levels, and resolved n-alkanes were depleted in weathered oil fractions. Furthermore, a shift in the relative importance of different boiling-point fraction ranges of the oils was observed on weathering. Generally, the lowest fraction range (C10-C16) disappeared, whereas the relative proportion of the highest (C28-C40) fraction range increased considerably. Remarkably, for the gas oil, this fraction shift was dependent on the oil concentration in sediment. Similarly, degradation of PAHs was strongly affected by the sedimentary oil content, indicating that the presence of oil stimulated PAH degradation. This phenomenon applied to both low- and high-molecular-weight PAHs, although the first group (3- and 4-ring PAHs) was degraded most. Results from the V. fischeri and DR-CALUX assay showed that in most cases, pore-water toxicity decreased on weathering. Combining the assay responses with chemical data indicated that the observed toxicity probably was not caused by the analyzed PAHs but, rather, by specific oil constituents instead.
许多沉积物受到油类残留物和多环芳烃（PAHs）混合物的污染，但对于此类混合物对栖息于沉积物中的生物的毒性以及风化过程中毒性的变化，人们了解甚少。在本研究中，我们调查了两年半自然风化期对添加了三种不同油类（一种瓦斯油、一种润滑油和一种原油；均在五个浓度下进行测试）的海洋沉积物中PAH/油类化学性质和毒性的影响。使用细菌（费氏弧菌）试验和体外化学激活荧光素酶表达试验（DR-CALUX；采用检测PAHs的条件）对生物可利用的、孔隙水中容纳的油/PAH组分的毒性进行了量化。化学分析结果表明所有三种油类均发生了（微生物）降解：风化过程中沉积物需氧量随油浓度增加而增加，总油浓度降至初始水平的17%至29%之间，风化油组分中可分辨的正构烷烃被消耗殆尽。此外，在风化过程中观察到了油类不同沸点馏分范围相对重要性的变化。一般来说，最低馏分范围（C10-C16）消失，而最高馏分范围（C28-C40）的相对比例大幅增加。值得注意的是，对于瓦斯油，这种馏分变化取决于沉积物中的油浓度。同样，PAHs的降解也受到沉积油含量的强烈影响，表明油的存在刺激了PAHs的降解。这种现象适用于低分子量和高分子量的PAHs，尽管第一组（三环和四环PAHs）降解最多。费氏弧菌试验和DR-CALUX试验的结果表明，在大多数情况下，孔隙水毒性在风化过程中降低。将试验响应与化学数据相结合表明，观察到的毒性可能不是由分析的PAHs引起的，而是由特定的油成分引起的。
