1. Sources and Significance
The haloacetic acids (HAAs) are formed by the chlorination of natural organic (humic and fulvic) matter. Utilities using chlorine as a water disinfectant generate haloacetic acids, usually as the second most prevalent group of known disinfection byproducts1; the primary group formed is usually the trihalomethanes. Toxicological studies indicate that dichloroacetic acid and trichloroacetic acid are animal carcinogens.2 The U.S. Environmental Protection Agency has promulgated a maximum contaminant level for the sum of 5 haloacetic acids.3