Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771, Athens, Greece.
Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600, Dübendorf, Switzerland; Department of Environmental Systems Science (D-USYS), ETH Zürich, 8092, Zürich, Switzerland.
Water Res. 2016 Oct 15;103:205-214. doi: 10.1016/j.watres.2016.07.029. Epub 2016 Jul 14.
Citalopram (CTR) is a worldwide highly consumed antidepressant which has demonstrated incomplete removal by conventional wastewater treatment. Despite its global ubiquitous presence in different environmental compartments, little is known about its behaviour and transformation processes during wastewater treatment. The present study aims to expand the knowledge on fate and transformation of CTR during the biological treatment process. For this purpose, batch reactors were set up to assess biotic, abiotic and sorption losses of this compound. One of the main objectives of the study was the identification of the formed transformation products (TPs) by applying suspect and non-target strategies based on liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS). The complementary use of reversed phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC) for the identification of polar TPs, and the application of in-house developed quantitative structure-retention relationship (QSRR) prediction models, in addition to the comprehensive evaluation of the obtained MS/MS spectra, provided valuable information to support identification. In total, fourteen TPs were detected and thirteen of them were tentatively identified. Four compounds were confirmed (N-desmethylCTR, CTR amide, CTR carboxylic acid and 3-oxo-CTR) through the purchase of the corresponding reference standard. Probable structures based on diagnostic evidence were proposed for the additional nine TPs. Eleven TPs are reported for the first time. A transformation pathway for the biotransformation of CTR was proposed. The presence of the identified TPs was assessed in real wastewater samples through retrospective analysis, resulting in the detection of five compounds. Finally, the potential ecotoxicological risk posed by CTR and its TPs to different trophic levels of aquatic organisms was evaluated by means of risk quotients.
西酞普兰（CTR）是一种全球范围内广泛使用的抗抑郁药，但常规废水处理方法并不能完全去除它。尽管它在不同的环境介质中无处不在，但人们对其在废水处理过程中的行为和转化过程知之甚少。本研究旨在扩展关于 CTR 在生物处理过程中命运和转化的知识。为此，设置了批式反应器来评估该化合物的生物、非生物和吸附损失。研究的主要目标之一是应用基于液相色谱-四极杆飞行时间质谱（LC-QTOF-MS）的可疑和非靶向策略来鉴定形成的转化产物（TPs）。反相液相色谱（RPLC）和亲水相互作用液相色谱（HILIC）的互补使用，用于鉴定极性 TPs，以及应用内部开发的定量结构-保留关系（QSRR）预测模型，除了对获得的 MS/MS 谱进行综合评估外，还提供了有价值的信息来支持鉴定。总共检测到 14 种 TPs，其中 13 种被初步鉴定。通过购买相应的对照标准，确认了其中 4 种化合物（N-去甲基西酞普兰、西酞普兰酰胺、西酞普兰羧酸和 3-氧代西酞普兰）。基于诊断证据，对另外 9 种 TPs 提出了可能的结构。有 11 种 TPs 是首次报道的。提出了 CTR 生物转化的转化途径。通过回顾性分析评估了在实际废水样品中存在的已鉴定 TPs，结果检测到了 5 种化合物。最后，通过风险商数评估了 CTR 及其 TPs 对水生生物不同营养级别的潜在生态毒理学风险。
