Analytical and toxicological evaluation of bioavailable naphthenic acids from oil sands process-affected water and groundwater using biomimetic extraction solid phase microextraction

环烷酸（NA）是天然存在于沥青中的有机化合物的高度复杂的混合物。最近的证据表明，NAs是油砂工艺用水（OSPW）中毒性最强的化学品之一。传统的分析方法来表征NA污染是不合适的预测潜在的生态毒性，因为这些方法无法表征个别NA化合物的生物利用度。本研究旨在发展一种仿生萃取-固相微萃取（BE-SPME）方法，作为评估有机污染物和地下水中生物可利用NAs毒性的替代方法。BE-SPME技术将被用作一种工具，根据系统暴露（即，脂质摄取）而不是外部水浓度。将使用气相色谱火焰离子化检测器（GC-FID）和大气压气相色谱飞行时间质谱（APGC-TOFMS）表征生物可利用部分的化学特征。将使用Microtox试验研究生物可利用部分的急性毒性。使用物理、化学和生物处理过程（即，吸附、臭氧化和生物处理）将用于验证该方法。通过使用该技术，将对未经处理和经处理的工艺水中的生物可利用的有机酸进行表征，有助于提高我们对经处理的工艺水对环境的潜在影响的理解。总的来说，这项工作将通过为分析和毒理学评价提供改进的筛选工具，支持其他侧重于污水测试、实地监测、场地评估和补救的研究，还将有利于支持组织-帝国石油-提供可用于风险评估目的的危害评估工具。

Naphthenic acids (NAs) are a highly complex mixture of organic compounds naturally present in bitumen. Recent evidence suggests that NAs are among the most acutely toxic chemical classes present in oil sands process water (OSPW). Traditional analytical methods to characterize NA contamination are not suitable predictors of potential ecotoxicity because these methods fail to characterize the bioavailability of individual NA compounds. This project aims to develop a biomimetic extraction - solid phase microextraction (BE-SPME) method as a surrogate to estimate the toxicity of bioavailable NAs from OSPW and groundwater. The BE-SPME technique will be used as a tool to compare toxicity test results on the basis of system exposure (i.e., lipid uptake) rather than on external water concentrations. Gas chromatography flame ionization detection (GC-FID) and atmospheric pressure gas chromatography time-of-flight mass spectrometry (APGC-TOFMS) will be used to characterize the chemical profile of the bioavailable fraction. Microtox assay will be used to investigate the acute toxicity of the bioavailable fraction. Treated samples using physico, chemical and biological treatment processes (i.e., adsorption, ozonation and biological treatment) will be used to validate the method. By using this technique, the characterization of the bioavailable organic acids in both untreated and treated process water will be conducted, helping to increase our understanding of the potential impacts of treated process water on the environment. Overall, this work will support other studies focusing on effluent testing, field monitoring, site assessment and remediation by providing an improved screening tool for analytical and toxicological evaluation and will also be beneficial for the supporting organization - Imperial Oil - to provide a hazard assessment tool that may be used for risk assessment purposes.