AWWA WQTC65751

Haloacetic acids (HAAs) are among the disinfection byproducts produced during chlorination of water containing natural organic matter and bromide. U.S. Environmental Protection Agency (USEPA) Methods 552.1 and 552.2 used to determine HAAs require tedious derivatization and multiple extraction steps followed by gas chromatography (GC) with electron capture detection (ECD) and mass spectrometry (MS). Ion chromatography-mass spectrometry (IC-MS and IC-MS/MS) offers a sensitive and selective alternative that does not require sample pretreatment. Water samples are directly injected into an ion chromatograph coupled to a triple quadrupole mass spectrometer. The separation of all 9 HAAs addressed in USEPA methods is achieved on either a 2 ? 250 mm or 1 ? 250 mm high-capacity ion exchange column using simple hydroxide gradients. Excellent peak resolution and linearity are achieved between 0.4 µg/L and 100 µg/L in a matrix containing up to 250 mg/L each of chloride and sulfate and 30 mg/L of nitrate. Using 13CClH2COOH as an internal standard, the detection limit is less than 0.4 µg/L for each of the five regulated haloacetic acids (HAA5) and less than 1 µg/L for the other four. No significant matrix effects are observed. Recoveries of all nine HAAs are greater than 90% in a simulated matrix of the above concentrations.