PDF(Pubmed)
Abstract：
Disinfection during tertiary municipal wastewater treatment is a necessary step to control the spread of pathogens; unfortunately, it also gives rise to numerous disinfection byproducts (DBPs), only a few of which are regulated because of the analytical challenges associated with the vast number of potential DBPs. This study utilized polydimethylsiloxane (PDMS) passive samplers, comprehensive two-dimensional gas chromatography (GC×GC) coupled with time-of-flight mass spectrometry (TOFMS), and non-negative matrix factorization (NMF) spectral deconvolution for suspect screening of DBPs in treated wastewater. PDMS samplers were deployed upstream and downstream of the chlorination unit in a municipal wastewater treatment plant located in Abu Dhabi, and their extracts were analyzed using GC×GC-TOFMS. A workflow incorporating a multi-tiered, eight-filter screening process was developed, which successfully enabled the reliable isolation of 22 candidate DBPs from thousands of peaks. The NMF spectral deconvolution improved the match factor score of unknown mass spectra to the reference mass spectra available in the NIST library by 17% and facilitated the identification of seven additional DBPs. The close match of the first-dimension retention index data and the GC×GC elution patterns of DBPs, both predicted using the Abraham solvation model, with their respective experimental counterparts-with the measured data available in the NIST WebBook and the GC×GC elution patterns being those observed for the candidate peaks-significantly enhanced the accuracy of peak assignment. Isotopic pattern analysis revealed a close correspondence for 11 DBPs with clearly visible isotopologues in reference spectra, thereby further strengthening the confidence in the peak assignment of these DBPs. Brominated analogues were prevalent among the detected DBPs, possibly due to seawater intrusion. The fate, behavior, persistence, and toxicity of tentatively identified DBPs were assessed using EPI Suite™ and the CompTox Chemicals Dashboard. This revealed their significant toxicity to aquatic organisms, including developmental, mutagenic, and endocrine-disrupting effects in certain DBPs. Some DBPs also showed activity in various CompTox bioassays, implicating them in adverse molecular pathways. Additionally, 11 DBPs demonstrated high environmental persistence and resistance to biodegradation. This combined approach offers a powerful tool for future research and environmental monitoring, enabling accurate identification and assessment of DBPs and their potential risks.
摘要：
三级城市污水处理期间的消毒是控制病原体传播的必要步骤；不幸的是，它还会产生许多消毒副产物(DBP)，由于与大量潜在DBP相关的分析挑战，其中只有少数受到监管。本研究利用聚二甲基硅氧烷(PDMS)无源采样器，全面的二维气相色谱（GC×GC）-飞行时间质谱（TOFMS），和非负矩阵分解（NMF）光谱反卷积，用于筛选处理过的废水中的可疑DBPs。PDMS采样器部署在位于阿布扎比的市政污水处理厂的氯化装置的上游和下游。并使用GC×GC-TOFMS分析其提取物。一个包含多层的工作流程，开发了八过滤器筛选工艺，这成功地实现了22个候选DBP与数千个峰的可靠隔离。NMF光谱反卷积将未知质谱与NIST库中可用的参考质谱的匹配因子得分提高了17%,并促进了七个额外DBP的鉴定。一维保留指数数据与DBPs的GC×GC洗脱模式的紧密匹配，两者都是用亚伯拉罕溶剂化模型预测的，与它们各自的实验对应物-NISTWebBook中提供的测量数据以及针对候选峰观察到的GC×GC洗脱模式-显着提高了峰分配的准确性。同位素模式分析显示，在参考光谱中，11个DBP与清晰可见的同位素密切相关，从而进一步增强这些DBP的峰值分配的置信度。溴化类似物在检测到的DBPs中普遍存在，可能是由于海水入侵。命运,行为，持久性,使用EPISuite™和CompTox化学品仪表板评估初步鉴定的DBP的毒性和毒性。这揭示了它们对水生生物的显著毒性，包括发展，诱变，和某些DBPs中的内分泌干扰作用。一些DBP在各种CompTox生物测定中也显示出活性，将它们与不利的分子途径联系起来。此外,11个DBPs表现出高度的环境持久性和对生物降解的抗性。这种组合方法为未来的研究和环境监测提供了强大的工具，能够准确识别和评估DBP及其潜在风险。
