Discovery of Emerging Disinfection by-products in Water using Gas Chromatography coupled with Orbitrap-based Mass Spectrometry
The disinfection of drinking water is required in order to protect consumers from potential waterborne infectious and parasitic pathogens. Water is commonly treated by adding chemical disinfectants, such as free chlorine, chloramines, chlorine dioxide, and ozone. However, although very effective in removing disease-causing microorganisms, these disinfectants can react with naturally occurring materials in the water and can form disinfection by-products (DBPs) which can be harmful to human health. In particular, compounds containing an iodo-group, i.e., iodinated DBPs (iodo-DBPs), may pose a greater health risk for the population exposed to them than their brominated and chlorinated analogues [1]. In recent years, several chemical classes of low molecular weight iodo-DBPs have been reported; however, many more may be still present in the unknown fraction (~50%) of halogenated material formed during disinfection treatments [2]. Therefore, complete characterization of iodo-DBPs present in DBP mixtures is crucial to further investigate their occurrence in disinfected waters and potential toxicity effects. The identification of emerging iodinated DBPs in water is difficult due to the complexity of this matrix and the low concentrations of these compounds. For this, analytical techniques with high resolving power, high mass accuracy and sensitivity are required. In this work, a novel gas chromatography (GC), coupled with high-resolution accurate mass Orbitrap mass spectrometer (the Thermo Scientific™ Q Exactive™ GC hybrid quadrupole-Orbitrap mass spectrometer), has been used for iodo-DBPs detection and accurate mass identification in chlorinated and chloraminated water samples ; C. P. acknowledges support provided by the European Union 7th R&D Framework Programme (FP7/2007e2013) under grant agreement 274379 (Marie Curie IOF) and the Secretary for Universities and Research of the Ministry of Economy and Knowledge of the Government of Catalonia and the COFUND programme of the Marie Curie Actions of the EU's FP7 (2014 BP_B00064). This work has been financially supported by the Generalitat de Catalunya (Consolidated Research Groups "2014 SGR 418 - Water and Soil Quality Unit" and 392 2014 SGR 291 - ICRA) and by the European Union's FP7 for research, technological development and demonstration under grant agreement nº 603437 (SOLUTIONS). The EU is not liable for any use that may be made of the information contained therein. ; Peer reviewed