On Tuesday 10 September 2019, Vittorio Albergamo will defend his PhD thesis
Thousands of anthropogenic organic compounds occur in natural drinking water sources such as surface waters and riverbank filtrates. In this thesis, high-resolution mass spectrometry (HRMS) was the main analytical tool to (i) investigate the passage of hydrophilic organics through reverse osmosis (RO) membranes and (ii) characterise polar contaminants in drinking water sources.
The potential of liquid chromatography coupled to HRMS to analyse polar organics at environmentally relevant concentrations is shown for a set of contaminants with diverse physicochemical properties in terms of size, hydrophilicity and charge. These target compounds dosed to a raw riverbank filtrate were removed with high efficacy by pilot-scale RO with standard membranes, highlighting RO’s suitability for drinking water production from natural waters requiring minimum pre-treatment. Small uncharged hydrophilics (< 150 Da), (moderately) hydrophobic compounds without a clear correlation to size, and small cations (< 186 Da) were found critical for RO processes. Similar results were obtained using mixed-matrix RO membranes.
Non-target screening (NTS) showed that many polar contaminants, including ones hitherto unknown to occur in source waters, are persistent and mobile during riverbank filtration and thus may pass the barriers applied for drinking water production. Effect-based methods (EBMs) with endpoints relevant for human health indicated that full-scale RO removed bioactive contaminants from bank filtrate. Bioactivity metadata of some of these compounds, whose structures were (tentatively) elucidated by NTS, supported the results of the EBMs.
The benefits and limitations of the methods used in this thesis are discussed in relation to science, society and drinking water production.