Haloacetic acids are byproducts formed when chlorine disinfectants react with organic matter in water. They are regulated contaminants linked to increased cancer risk.

Haloacetic acids (HAAs) are a group of compounds that form when chlorine-based disinfectants react with naturally occurring organic matter in water. The five most common HAAs are regulated by the EPA as a single group (HAA5). These compounds are measured in parts per billion (ppb) using laboratory analysis. While disinfection is crucial for preventing waterborne diseases, the EPA has set limits on HAAs due to potential health risks from long-term exposure. Water systems can reduce HAA formation by optimizing treatment processes and removing organic matter before disinfection.