Brominated and iodinated disinfection by-products: Recent advances in formation, characterization, and toxicity

The formation of brominated and iodinated disinfection by-products is of concern due to impaired water quality, taste and odor issues and health concerns. Progress on the identification of precursors among the complex organic matter reveals that low molecular weight by-products are the main toxicity drivers. These by-products could however come from the degradation of high-molecular weight organic matter especially in presence of iodide during chlorination or chloramination and algal bloom events. Alternative oxidants such as peracids or periodate reach different levels of assessment considering the formation of by-products demonstrating breakthrough in this field but also remaining gaps to be filled. • low molecular weight disinfection by-products are the main toxicity drivers • High molecular weight organic matter is of concern in presence of iodide • In contrast of performic acid, peracetic acid forms halogenated organic disinfection by-products • Mass spectrometry progressed on the identification of brominated and iodinated disinfection by-products