NSERC Industrial Chair on Drinking Water, Department of Civil Engineering, Polytechnique School of Montreal, Montreal, QC, Canada.
Environment and Climate Change Canada, Aquatic Contaminants Research Division, Montreal, QC, Canada.
Chemosphere. 2021 Aug;277:130216. doi: 10.1016/j.chemosphere.2021.130216. Epub 2021 Mar 13.
Drinking water producers continuously develop innovative treatment processes to effectively remove organic micropollutants from raw water. Biological ion-exchange (BIEX) water treatment is one of these new techniques under development and showing great potential. In order to investigate if biodegradation is highly involved in such a removal technique, cultures were prepared with microorganisms sampled on the resins of a BIEX filter. Then, organic micropollutants were spiked into these cultures and their (bio)degradation was followed over 30 days by ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS). The purpose of this study was firstly to develop an analytical method using UHPLC-HRMS able to monitor the degradation of three spiked organic micropollutants in culture. Beyond quantification, this method allowed the simultaneous recording of fragmentation information via the use of a data-independent acquisition approach to perform a non-exhaustive search of transformation products related to the spiked micropollutants in culture aliquots. Secondly, a data treatment approach was developed to process raw spectral data generated by aliquots analysis by optimizing the precursor isolation mass windows, the accurate mass tolerance, peak intensity thresholds and choice of database. The use of this new method with a post-data acquisition treatment approach completed by the exhaustive study of fragmentation spectra allowed the tentative identification of 11 transformation products related to the spiked compounds. Finally, 16S rRNA gene amplicon sequencing revealed that bacterial genera known for their ability to degrade the spiked micropollutants were present in the microbial community of the BIEX drinking water filter.
饮用水生产商不断开发创新的处理工艺，以有效去除原水中的有机微量污染物。生物离子交换 (BIEX) 水处理是正在开发的新技术之一，具有很大的潜力。为了研究生物降解是否高度参与这种去除技术，用从 BIEX 过滤器树脂上取样的微生物制备了培养物。然后，将有机微量污染物注入这些培养物中，并通过超高效液相色谱-高分辨率质谱联用 (UHPLC-HRMS) 跟踪 30 天的（生物）降解情况。本研究的目的首先是开发一种使用 UHPLC-HRMS 的分析方法，能够监测培养物中三种注入有机微量污染物的降解情况。除了定量分析外，该方法还通过使用数据独立采集方法，同时记录碎片信息，对培养物中与注入微量污染物相关的转化产物进行非穷尽搜索。其次，开发了一种数据处理方法来处理通过对原始光谱数据进行处理，通过优化前体分离质量窗口、精确质量公差、峰强度阈值和数据库选择来处理原始光谱数据。使用这种新方法并结合通过对碎片光谱进行详尽研究完成的后数据采集处理方法，能够初步鉴定出与注入化合物相关的 11 种转化产物。最后，16S rRNA 基因扩增子测序显示，已知能够降解注入微量污染物的细菌属存在于 BIEX 饮用水过滤器的微生物群落中。
