Formation mechanism of 13 new polar phenolic chlorinated and brominated disinfection byproducts in drinking water

Abstract

Recently, 13 new polar phenolic chlorinated and brominated disinfection byproducts (Cl-/Br-DBPs) have been identified in drinking water by using multiple reaction monitoring (MRM), precursor ion scan, and product ion scan of ultra-performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry (UPLC/ESI-tqMS). The new DBPs have attracted increasing concern since they were proved to have higher cytotoxicity, developmental toxicity, and growth inhibition than aliphatic DBPs, and form trihalomethanes and haloacetic acids via decomposition. In this study, a series of samples were prepared by reacting gallic acid with chlorine/monochloramine in the presence of bromide to simulate chlorinated/chloraminated drinking water samples with gallic acid as carbon source. The reaction products, intermediate compounds, and gallic acid were analyzed using UPLC/ESI-tqMS. Gallic acid was proved to exist in both simulat and real source waters, and 10 new polar phenolic Cl-/Br-DBPs were identified and quantified in the chlorinated/chloramined gallic acid reaction solutions, suggesting that gallic acid is one of the precursors of the 13 new phenolic DBPs.