University of Cyprus, Department of Civil and Environmental Engineering, University of Cyprus, 75 Kallipoleos Street, 1678 Nicosia, Cyprus.
Sci Total Environ. 2013 Apr 15;450-451:356-65. doi: 10.1016/j.scitotenv.2012.05.096. Epub 2012 Jun 27.
Ofloxacin (OFL), a broad-spectrum and widespread-used photolabile fluoroquinolone, is frequently found in treated wastewaters, aquatic and terrestrial ecosystems leading to increasing concern during the past decades regarding its effects to the environment and human health. The elimination of OFL and other xenobiotics by the application of advanced oxidation processes using photolytic (PL) and photocatalytic (PC) treatments seems promising. However, an integrated assessment scheme is needed, in which, not only the removal of the parent compound, but also the effects of the photo-transformation products (PTPs) are investigated. For this purpose, in the present study, a chronic ecotoxic assessment using representative bacteria of marine and terrestrial ecosystems and a cytostatic and genotoxic evaluation using hepatoma cell line were performed. PL and PC treatments of OFL were applied using UV radiation. The photo-transformation of OFL during the treatments was monitored by DOC measurements and UPLC-MS/MS analysis. The chronic ecotoxicity of OFL and treated samples was evaluated using Pseudomonas putida and Vibrio fischeri; whereas the cytostasis and genotoxicity were estimated by the cytokinesis-block micronucleus assay (CBMN). The main results suggest that photo-transformation of OFL took place during these treatments since the concentration of OFL decreased when the irradiation time increased, as quantified by UPLC-MS/MS analysis, and this was not coupled with an analogous DOC removal. Furthermore, nine compounds were identified as probable PTPs formed through piperazinyl dealkylation and decarboxylation. The ecotoxicity of treated solutions to the bacteria studied decreased while the cytostasis to the hepatoma cell line remained at low levels during both treatments. However, the genotoxicity to the hepatoma cell line demonstrated a different pattern in which treated samples induced a greater number of MNi for the 4-16 min of irradiation (p<0.05) during both treatments. After 64 min of irradiation, the effects decreased to non genotoxic levels (p<0.05). These findings suggest that UV radiation for various treatment processes (catalytic or not), such as disinfection, may create genotoxic by-products. Therefore, in relevant technical applications, the residence time during treatment should receive special attention.
氧氟沙星（OFL）是一种广谱且广泛使用的光不稳定氟喹诺酮类药物，经常在处理过的废水中以及水生和陆地生态系统中被发现。在过去几十年中，由于其对环境和人类健康的影响，人们越来越关注它。使用光解（PL）和光催化（PC）处理的高级氧化工艺（AOPs）来消除 OFL 和其他外来化合物似乎很有希望。但是，需要一种综合评估方案，其中不仅要去除母体化合物，还要研究光转化产物（PTPs）的影响。为此，在本研究中，使用海洋和陆地生态系统的代表性细菌进行了慢性生态毒性评估，并使用肝癌细胞系进行了细胞抑制和遗传毒性评估。使用紫外线辐射对 OFL 进行 PL 和 PC 处理。通过 DOC 测量和 UPLC-MS/MS 分析监测 OFL 的光转化过程。使用恶臭假单胞菌和发光弧菌评估 OFL 和处理样品的慢性生态毒性；而细胞抑制和遗传毒性则通过胞质分裂阻断微核试验（CBMN）进行评估。主要结果表明，在这些处理过程中发生了 OFL 的光转化，因为 UPLC-MS/MS 分析定量表明，随着辐照时间的增加，OFL 的浓度降低，并且这与类似的 DOC 去除没有关联。此外，鉴定出了九种可能通过哌嗪基脱烷基化和脱羧形成的 PTP。研究的细菌对处理溶液的生态毒性降低，而两种处理方法中对肝癌细胞系的细胞抑制作用仍保持在较低水平。然而，肝癌细胞系的遗传毒性表现出不同的模式，其中在两种处理方法中，在 4-16 分钟的辐照期间，处理样品诱导的 MNi 数量更多（p<0.05）。辐照 64 分钟后，影响降低至非遗传毒性水平（p<0.05）。这些发现表明，紫外线辐射用于各种处理过程（催化或不催化），例如消毒，可能会产生遗传毒性副产物。因此，在相关技术应用中，处理过程中的停留时间应特别注意。
