Formation and influencing factors of disinfection by-products from bacterial materials in drinking water distribution systems

In recent years, the contribution of bacterial materials in water distribution systems to DBPs has attracted widespread attention from researchers. The risks and influencing factors of bacterial DBPs are reviewed. Factors affecting the generation of bacterial DBPs include the characteristics of bacterial materials, disinfection process, piping materials, and water quality. Among the major components of biofilms, proteins or amino acids have the greatest risk of DBPs. Among the commonly used disinfection methods, chlorine is more suitable for continuous disinfection of pipe networks than chloramine, but chlorine dioxide may be a better substitute in the future. Pipes with good biological stability, such as polyethylene (PE) pipe, should be encouraged to be used in water supply networks. Periodic removal of biofilms, reduction of organic matter and bromide ion concentrations, and maintenance of high flow rates are effective means to reduce bacterial DBPs. The control, removal and monitoring devices of tube wall biofilm need to be further developed and promoted. In the future, it is urgent to develop new disinfectants that are not easy to react with biomolecules and natural organic matter, and produce fewer or no by-products. HIGHLIGHTS Proteins or amino acids induce the greatest risk of DBP formation.; Chlorine is more suitable for continuous disinfection of pipe networks than chloramine, but chlorine dioxide may be a better substitute.; PE pipes should be encouraged to be used in water supply network.; The concentration of organic matter and bromide ions in the water should be reduced as much as possible and the high flow rate of the water should be maintained.;