Improved Method for the Determination of Haloacetic Acids in Drinking Water by HPLC-MS/MS

Oral Presentation

Prepared by A. Pierri1, S. Orlowicz2, X. Wei2
1 - Weck Laboratories, Inc., 14859 Clark Avenue, City of Industry, CA, 91745, United States
2 - Phenomenex, 411 Madrid Drive, Torrance, CA, 90501, United States


Contact Information: agustin.pierri@wecklabs.com; 626-336-2139


ABSTRACT

Haloacetic acids are a regulated class of disinfection byproducts commonly found in drinking water that are formed from the reaction of naturally occurring organic materials such as humic and fulvic acids with chlorine and chloramines. For compliance, these compounds are analyzed by EPA Method 552.3 (microextraction-derivatization-GC/ECD) or the recently introduced EPA Method 557 (direct injection ion chromatography-MS/MS). Both of these methods leave much to be desired in terms of routine laboratory implementation, robustness and productivity.

In this presentation we will describe an improvement on EPA method 557 for the detection of haloacetic acids in drinking water. This technique relies on conventional reversed-phase liquid chromatography instead of ion chromatography, providing a simpler and more robust analytical procedure when compared to the established EPA methods 552.3 and 557. The tedious and error-prone microextraction and derivatization steps from Method 552.3 are eliminated by using driect-injection LCMS. Additionally, using traditional LC-MS modifiers in the mobile phase eliminates the need for a ion surpressor to mitigate the negative effects of a high ionic strength mobile phase on the mass spectrometer. We will present data that demonstrates significant advantages over current methods including shorter analysis times, greater sensitivity and improved instrument stability while maintaining high data quality and precision when compared to EPA method 552.3.