Emerging contaminants have been extensively studied for occurrence and fate in drinking water sources throughout the developed world, but the risk of these compounds in most of the developing world has not been assessed. The goal of our study was to use non-targeted screening methods based on high-resolution mass spectrometry to determine the chemical profile of polar organic pollutants in Haitian drinking water sources and to determine the distribution of chemical classes in Haitian waters. The analytical strategy used was based on UHPLC coupled to high-resolution, accurate mass MS/MS (LCHRMS), using an Orbitrap Fusion Lumos mass spectrometer (ThermoFisher). High resolution, data-dependent MS/MS with HCD fragmentation and Orbitrap mass analysis was performed. High resolution product ion spectra were used to interrogate tandem MS spectral libraries for compound identification, together with an <i>in-silico</i> mass spectrometry workflow using chemoinformatic methods integrated with a commercial HRMS data processing system. Tentatively identified compounds were confirmed with authentic standards where possible. Using our workflow, 3884 unique chemical features were identified across the water samples. Compounds such as carbamazepine, propiconazole, verapamil and iminostilbene were positively identified using retention time matching and authentic standards. An additional 97 compounds were tentatively identified using mass spectral library databases, these include chemicals such as acridine, trimethoprim and amfepramone. Of these positively and tentatively identified compounds: 26% were agrochemicals, 23% were pharmaceuticals, 18% were natural products, 14% were industrial, 12% were chemicals, 4% were drugs and 3% were personal care products. The R package EnviHomolog was used to identify potential ethoxylated surfactants, which are homologous series compounds. This program identified 221 features across 35 series that were consistent with the ethoxylated surfactant series. We plan to further explore non-targeted screening approaches to better understand the chemical complexity of Haitian drinking water sources. Overall, our data indicates that various organic contaminant classes make up the chemical profile of Haitian waters.

Assessing the chemical water quality of Haitian waters: A non-targeted assessment of organic contaminants in the developing world

2019 Spring National Meeting

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