IODIPRO - Iodinated disinfection byproducts under climate change derived scenarios: water scarcity and seawater intrusion
Different classes of iodinated disinfection by-products (I-DBPs) form during chemical disinfection of water with high iodide content. I-DBPs are more toxic than bromine- and chlorine-containing DBPs. Sea water intrusion and water scarcity are predicted to increase due to climate change. These effects will be of special relevance in coastal warm areas, like the Mediterranean region. Under both scenarios, an increase of the iodide (and bromide) content of the source waters intended for human consumption is expected, and hence, the formation of toxic Br- and I-DBPs in chemically disinfected water. In this context, the main goal of this project was to investigate the formation of I-DBPs and the potential derived risks to human health under these climate change-derived scenarios. The research strategy of IODIPRO included the evaluation of the formation potential of I-DBPs and additional emerging DBPs of water containing different proportions of sea water and desalinated water after lab-scale chlorination and chloramination reactions and of water mixtures being currently supplied to the city and metropolitan area of Barcelona. The DBP mixtures were chemically characterized by means of high and low resolution mass analyzers coupled to gas/liquid chromatography. Analytical efforts focused on the quantification of trihalomethanes, haloacetic acids, haloacetonitriles, haloacetaldehydes and haloacetamides, and in particular, iodinated forms of these chemical classes. The toxicity of the main DBPs generated and the toxicity potency of the waters investigated was also assessed from experimental toxicity data published in the literature. Finally, the integration of both toxicity and chemical information allowed elaborating lists of “priority I-DBPs” and “priority emerging DBPs” in drinking water. This information was provided to drinking water management authorities to help them provide safe drinking water and protect public health from the upcoming water quality changes.