Emerging disinfection byproducts: A review on their occurrence and control in drinking water treatment processes

The occurrence of disinfection byproducts (DBPs) is related both to drinking water treatment (DWT) processes and to raw water’s characteristics. Emerging pollutants typically occur in low concentrations and are not removed by conventional DWT processes. Emerging DBPs appear within the DWT or in the distribution system due to the combination of disinfection agents (especially chlorine) with precursors as: natural organic matter (NOM), algal organic matter (AOM), anthropogenic contaminants (pesticides, pharmaceuticals, detergents etc.), brominated and iodinated compounds. This study has as main goal a consistent analysis of the major problems caused by emerging DBPs to drinking water supplies. It presents a comprehensive review of the research efforts related to emerging DBPs considering three viewpoints: 1. an overview of their classification, legislative framework, methods of analysis, disinfection operational conditions and removal processes; 2. their occurrence, fate, health effects and impacts; 3. the analysis of the advanced DWT processes that might be used for the removal and control of precursors and DBPs, with a focus on pilot and full-scale installations. All presented case studies considered pollutants removed, process conditions and efficiencies, and a critical assessment of processes based on membranes, advanced oxidation and adsorption on activated carbon or other materials. The main challenges of the control and removal of emerging DBPs are their low concentrations and the technical and economic sustainability of their application at full-scale, which need to be carefully adapted to local boundary conditions.