Effects of ascorbate and carbonate on the conversion and developmental toxicity of halogenated disinfection byproducts during boiling of tap water. (September 2020)

• Record Type: Journal Article
• Authors: Liu, Jiaqi; Li, Yu; Jiang, Jingyi; Zhang, Xiangru; Sharma, Virender K.; Sayes, Christie M.
• Is Part Of: Chemosphere. Volume 254(2020)
• Publication Date: 2020-09
• Subjects: Disinfection byproducts -- DBPs -- Ascorbate -- Carbonate -- Toxicity -- Boiling; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2020.126890
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Chlorine disinfection inactivates pathogens in drinking water, but meanwhile it causes the formation of halogenated disinfection byproducts (DBPs), which may induce adverse health effects. Humans are unavoidably exposed to halogenated DBPs via tap water ingestion. Boiling of tap water has been found to significantly reduce the concentrations of halogenated DBPs. In this study, we found that compared with boiling only, adding ascorbate (vitamin C) or carbonate (baking soda) to tap water and then boiling the water further reduced the level of total organic halogen (a collective parameter for all halogenated DBPs) by up to 36% or 28%, respectively. Adding ascorbate removed the chlorine residual in tap water and thus prevented the formation of more halogenated DBPs in the boiling process. Adding carbonate elevated pH of tap water and consequently enhanced the hydrolysis (dehalogenation) of halogenated DBPs or led to the formation of more trihalomethanes that might volatilize to air during the boiling process. The comparative developmental toxicity of the DBP mixtures in the water samples was also evaluated. The results showed that adding a tiny amount of sodium ascorbate or carbonate (2.5–5.0 mg/L) to tap water followed by boiling for 5 min reduced the developmental toxicity of tap water to a substantially lower level than boiling only. The addition of sodium ascorbate or carbonate to tap water in household could be realized by preparing them in tiny pills. This study suggests simple and effective methods to reduce the adverse effects of halogenated DBPs on humans through tap water ingestion. Graphical abstract: Image 1 Highlights: Ascorbate prevented the formation of more halo-DBPs in tap water boiling. Adding ascorbate and boiling was better in detoxifying tap water than boiling only. Carbonate addition enhanced thermal hydrolysis of halo-DBPs in tap water. Adding carbonate and boiling was better in detoxifying tap water than boiling only.