Analysis of disinfection by-products in drinking water by LC-MS and related MS techniques

Current research indicates that much of the unidentified fraction of drinking water disinfection by-products (DBPs) is highly polar and of high molecular weight. The combination of liquid chromatography and mass spectrometry (LC-MS) is being increasingly used for the direct analysis of these highly polar, hydrophilic DBPs and for the exploration of high molecular weight by-products. Further, improvements in LC-MS instrumentation and analytical techniques are providing low μg/L and ng/L detection limits, which allow trace levels of DBPs to be measured. This review covers recent applications of LC-MS and other related techniques, such as flow injection-atmospheric pressure chemical ionization and electrospray ionization (ESI)-MS, high-field asymmetric waveform ion mobility spectrometry-ESI-MS, membrane-introduction MS, and ion chromatography-ESI-MS for measuring known DBPs and exploring the nature of previously uncharacterized DBPs.