AWWA JAW71679

Degradation of tribromoacetic acid (TBAA) in pipe reactors constructed of new and previously in-service iron pipe was investigated to evaluate the potential role of abiotic reduction in the loss of disinfection byproducts (DBPs) in distribution systems. Results showed that DBPs that are readily degraded by iron metal or ferrous iron associated with iron oxides can compete with dissolved oxygen for reduction equivalents at the pipe surface, indicating that abiotic reduction of highly reactive DBPs at the pipe wall may be an important loss process in distribution systems. Given that brominated and iodinated DBPs have been shown to be more toxic than their chlorinated analogues, the finding that abiotic reduction may lead to their destruction, and thus lower consumer exposure to them, should be of considerable interest to water utility managers. The process (which previously has not been considered in the fate of DBPs) can be used in models to help evaluate and predict DBP levels in distribution systems. Includes 33 references, table, figures.