School of Biotechnology and Biomolecular Sciences, UNSW Sydney, NSW 2052, Australia.
Australian Antarctic Division, 203 Channel Highway, Kingston, TAS 7050, Australia.
Sci Total Environ. 2019 Nov 1;689:390-397. doi: 10.1016/j.scitotenv.2019.06.389. Epub 2019 Jun 24.
Hydrocarbon polar metabolites are gaining interest from industry and the remediation community due to their ubiquity and uncertainty around their toxicity. In this study, we used headspace-gas chromatography/mass spectrometry (HS-GC/MS) to characterize polar metabolites present in elutriates derived from uncontaminated, freshly hydrocarbon contaminated and partially remediated Antarctic soils. Elutriates represent the bioavailable fraction and may be used as a proxy for leachate runoff in environmental risk assessments. Control and contaminated soil elutriates were analysed for the presence of 12 aldehydes and two ketones, which cover a broad spectrum of metabolites, ranging from nC - nC carbon chain length. A total of nine aldehydes were detected in the soil elutriates. Types of aldehydes present in uncontaminated and hydrocarbon contaminated elutriates were similar. Among the polar metabolites measured in elutriates, acetaldehyde was most abundant in partially remediated soils. Microtox assays were used to determine the potential toxicity of elutriates. In addition, three aldehydes that were present at the highest concentrations in the contaminated and partially remediated soil elutriates (acetaldehyde, octanal and undecanal) were tested as single compounds. Contaminated soil elutriates tested were found to be toxic, with partially remediated elutriates less toxic than freshly contaminated elutriates. None of the three aldehydes tested separately were toxic at levels at which they were measured in elutriates. We infer that high levels of acetaldehyde in partially remediated soil due to hydrocarbon degradation highlight the potential of this metabolite as a useful chemical marker for hydrocarbon degradation under certain conditions. Microtox was sensitive to metabolites and provided a useful initial screening tool for elutriates.
烃类极性代谢物因其普遍性以及其毒性的不确定性，引起了工业界和修复领域的关注。在这项研究中，我们使用顶空-气相色谱/质谱法（HS-GC/MS）来表征从未受污染、新近烃类污染和部分修复的南极土壤中提取的浸出液中的极性代谢物。浸出液代表了生物可利用的部分，可用作环境风险评估中沥出物径流的替代物。我们分析了对照和污染土壤浸出液中是否存在 12 种醛和 2 种酮，这些醛和酮涵盖了从 nC-nC 碳链长度的广泛代谢物。在土壤浸出液中检测到了总共 9 种醛。未受污染和烃类污染浸出液中存在的醛的类型相似。在测量的浸出液极性代谢物中，乙醛在部分修复土壤中最为丰富。我们使用 Microtox 测定法来确定浸出液的潜在毒性。此外，还测试了在污染和部分修复土壤浸出液中浓度最高的三种醛（乙醛、辛醛和十一醛）作为单一化合物。测试发现污染土壤浸出液具有毒性，部分修复浸出液的毒性低于新污染浸出液。在浸出液中测量到的这三种醛中，没有一种在其浓度下具有毒性。我们推断，由于烃类降解导致部分修复土壤中乙醛含量较高，这突出了该代谢物作为某些条件下烃类降解的有用化学标志物的潜力。Microtox 对代谢物敏感，为浸出液提供了有用的初始筛选工具。
