Analysis of haloacetic acids in drinking water using post-column reaction-ion chromatography with on-line internal standardization

Abstract

A post-column reaction-ion chromatography analyzer (PCR-IC) with automated internal standardization (IS) has been optimized to determine nine haloacetic acid (HAAs) species in drinking water while operating in near real-time with a one hour analysis time. The IS-PCR-IC method requires minimal sample preparation that consists of passing water samples through cartridges to remove anions and introducing the pretreated samples into the on-line channel of the automated instrumentation. Two sets of water samples have been analyzed and method detection limit (MDL), accuracy and precision measurements have been conducted prior to the water sample analysis. The experimental MDL values for the HAA species ranged from 1.4 to 7.8 μg L⁻¹; the accuracy ranged from 75.9 to 112%; and the precision ranged from 6.2 to 34.6%. The concentration of each HAA and the Total HAAs found in these water samples were determined using internal standardization and the results were compared to USEPA Method 552.3. The bias estimates between these two methods for Total HAA9 range from −8.3 to 12.5 μg L⁻¹.