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Disinfection byproduct

Bo Shao, Li Mao, Na Qu, Ya-Fen Wang, Hui-Ying Gao, Feng Li, Li Qin, Jie Shao, Chun-Hua Huang, Dan Xu, Lin-Na Xie, Chen Shen, Xiang Zhou, Ben-Zhan Zhu
2,6-Dibromohydroquinone (2,6-DBrHQ) has been identified as an reactive metabolite of many brominated phenolic environmental pollutants such as tetrabromobisphenol-A (TBBPA), bromoxynil and 2,4,6-tribromophenol, and was also found as one of disinfection byproducts in drinking water. In this study, we found that the combination of 2,6-DBrHQ and Cu(II) together could induce synergistic DNA damage as measured by double strand breakage in plasmid DNA and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) formation, while either of them alone has no effect...
January 3, 2017: Free Radical Biology & Medicine
Kaelin M Cawley, Amanda K Hohner, David C Podgorski, William T Cooper, Julie A Korak, Fernando L Rosario-Ortiz
To characterize the effects of thermal-alteration on water extractable organic matter (WEOM), soil samples were heated in a laboratory at 225, 350, and 500 °C. Next, heated and unheated soils were leached, filtered, and analyzed for dissolved organic carbon (DOC) concentration, optical properties, molecular size distribution, molecular composition, and disinfection byproduct (DBP) formation following the addition of chlorine. The soils heated to 225 °C leached the greatest DOC and had the highest C- and N-DBP precursor reactivity per unit carbon compared to the unheated material or soils heated to 350 or 500 °C...
December 29, 2016: Environmental Science & Technology
Xuexiang He, Mark Elkouz, Mandu Inyang, Eric Dickenson, Eric C Wert
Spatial and temporal variations of trihalomethanes (THMs) in distribution systems have challenged water treatment facilities to comply with disinfection byproduct rules. In this study, granular activated carbon (GAC) and modified GAC (i.e., Ag-GAC and TiO2-GAC) were used to treat chlorinated tap water containing CHCl3 (15-21μg/L), CHBrCl2 (13-16μg/L), CHBr2Cl (13-14μg/L), and CHBr3 (3μg/L). Following breakthrough of dissolved organic carbon (DOC), GAC were regenerated using conventional and novel methods...
December 9, 2016: Journal of Hazardous Materials
Tarek Manasfi, Michel De Méo, Carole Di Giorgio, Bruno Coulomb, Jean-Luc Boudenne
Water disinfection treatments result in the formation of disinfection byproducts (DBPs) that have been linked to adverse human health outcomes including higher incidence of bladder and colorectal cancer. However, data about the genotoxicity of DBPs is limited to only a small fraction of compounds. Chloral hydrate (CH) and bromal hydrate (BH) are two trihaloacetaldehydes commonly detected in disinfected waters, but little is known about their genotoxicity, especially BH. We investigated the genotoxicity of CH and BH using a test battery that includes three in vitro genotoxicity assays...
January 2017: Mutation Research
Yun Yu, David A Reckhow
Haloacetamides (HAMs) are a class of newly identified nitrogenous disinfection byproducts (N-DBPs) whose occurrence in drinking waters has recently been reported in several DBP surveys. As the most prominent HAM species, it is commonly acknowledged that 2,2-dichloroacetamide (DCAM) is mainly generated from dichloroacetonitrile (DCAN) hydrolysis because the concentrations of these two compounds are often well correlated. Instead of DCAM, a previously unreported N-DBP, N-chloro-2,2-dichloroacetamide (N-Cl-DCAM), was confirmed in this study as the actual DCAN degradation product in chlorinated drinking waters...
December 20, 2016: Environmental Science & Technology
Peizhe Sun, Wan-Ning Lee, Ruochun Zhang, Ching-Hua Huang
Photoactivation of aqueous chlorine could promote degradation of chlorine-resistant and photochemically stable chemicals accumulated in swimming pools. This study investigated the degradation of two such chemicals, N,N-diethyl-3-methylbenzamide (DEET) and caffeine, by low pressure ultraviolet (UV) light and simulated sunlight (SS) activated free chlorine (FC) in different water matrices. Both DEET and caffeine were rapidly degraded by UV/FC and SS/FC but exhibited different kinetic behaviors. The degradation of DEET followed pseudo-first-order kinetics, whereas the degradation of caffeine accelerated with reaction...
December 20, 2016: Environmental Science & Technology
Minju Lee, Tony Merle, Daniel Rentsch, Silvio Canonica, Urs von Gunten
The abatement of 9 polychloro-1,3-butadienes (CBDs) in aqueous solution by ozone, UV-C(254 nm) photolysis, and the corresponding advanced oxidation processes (AOPs) (i.e., O3/H2O2 and UV/H2O2) was investigated. The following parameters were determined for 9 CBDs: second-order rate constants for the reactions of CBDs with ozone (kO3) (<0.1-7.9 × 10(3) M(-1) s(-1)) or with hydroxyl radicals (k(•)OH) (0.9 × 10(9) - 6.5 × 10(9) M(-1) s(-1)), photon fluence-based rate constants (k') (210-2730 m(2) einstein(-1)), and quantum yields (Φ) (0...
January 3, 2017: Environmental Science & Technology
Koji Kosaka, Takahiko Nakai, Yuta Hishida, Mari Asami, Keiko Ohkubo, Michihiro Akiba
Halobenzoquinones are a group of disinfection byproducts formed by chlorination of certain substances in water. However, to date, the identities of halobenzoquinone precursors remain unknown. In this study, the formation of 2,6-dichloro-1,4-benzoquinone (DCBQ), a typical halobenzoquinone, from 31 aromatic compounds was investigated after 60 min of chlorination. DCBQ was formed from 21 compounds at molar formation yields ranging from 0.0008% to 4.9%. Phenol and chlorinated phenols served as DCBQ precursors, as reported previously...
December 7, 2016: Water Research
Erin T Martin, Caitlyn M McGuire, Mohammad S Mubarak, Dennis G Peters
Electrochemical reduction of halogenated organic compounds is gaining increasing attention as a strategy for the remediation of environmental pollutants. We begin this review by discussing key components (cells, electrodes, solvents, and electrolytes) in the design of a procedure for degrading a targeted pollutant, and we describe and contrast some experimental techniques used to explore and characterize the electrochemical behavior of that pollutant. Then, we describe how to probe various mechanistic features of the pertinent electrochemistry (including stepwise versus concerted carbon-halogen bond cleavage, identification of reaction intermediates, and elucidation of mechanisms)...
December 28, 2016: Chemical Reviews
Jiaqi Liu, Xiangru Zhang, Yu Li
Chlorine disinfection of wastewater effluents rich in bromide and iodide ions results in the formation of relatively toxic bromo- and iodo-disinfection byproducts (DBPs), especially highly toxic bromophenolic and iodophenolic DBPs, which could harm the marine ecosystem when they are discharged into receiving seawater along with the wastewater effluents. In this study, we investigated the conversion of three individual halophenolic DBPs (5-bromosalicylic acid, 2,5-dibromohydroquinone, and 2,4,6-triiodophenol) and two chlorinated saline wastewater DBP mixtures in seawater...
January 3, 2017: Environmental Science & Technology
Stephanie Spahr, Olaf A Cirpka, Urs von Gunten, Thomas B Hofstetter
N-Nitrosodimethylamine (NDMA) is a carcinogenic disinfection byproduct from water chloramination. Despite the identification of numerous NDMA precursors, essential parts of the reaction mechanism such as the incorporation of molecular O2 are poorly understood. In laboratory model systems for the chloramination of secondary and tertiary amines, we investigated the kinetics of precursor disappearance and NDMA formation, quantified the stoichiometries of monochloramine (NH2Cl) and aqueous O2 consumption, derived (18)O-kinetic isotope effects ((18)O-KIE) for the reactions of aqueous O2, and studied the impact of radical scavengers on NDMA formation...
January 3, 2017: Environmental Science & Technology
Naoko Munakata, Jeff Kuo
A review of the literature published in 2015 on topics relating to disinfection processes is presented. This review is divided into the following sections: disinfection methods, disinfection byproducts, and microbiology and microbial communities.
October 2016: Water Environment Research: a Research Publication of the Water Environment Federation
Yu Li, Xiangru Zhang, Mengting Yang, Jiaqi Liu, Wanxin Li, Nigel J D Graham, Xiaoyan Li, Bo Yang
Chlorination is extensively applied for disinfecting sewage effluents, but it unintentionally generates disinfection byproducts (DBPs). Using seawater for toilet flushing introduces a high level of bromide into domestic sewage. Chlorination of sewage effluent rich in bromide causes the formation of brominated DBPs. The objectives of achieving a disinfection goal, reducing disinfectant consumption and operational costs, as well as diminishing adverse effects to aquatic organisms in receiving water body remain a challenge in sewage treatment...
February 2017: Chemosphere
Ye Du, Qian-Yuan Wu, Yun Lu, Hong-Ying Hu, Yang Yang, Rui Liu, Feng Liu
Toxic and harmful disinfection byproducts (DBPs) were formed during wastewater chlorination. It was recently suggested that cytotoxicity to mammalian cells reflects risks posed by chlorinated wastewater. Here, ATP assays were performed to evaluate the cytotoxicity to mammalian cells. Chlorination significantly increased cytotoxicity of treated wastewater. Factors affecting cytotoxicity formation during wastewater chlorination were investigated. Quenching with sodium thiosulfate and ascorbic acid decreased the formed cytotoxicity, while ammonium kept the cytotoxicity stable...
February 15, 2017: Journal of Hazardous Materials
Yongfeng Deng, Yan Zhang, Yifeng Lu, Kai Lu, Hao Bai, Hongqiang Ren
Bromoacetonitriles (BANs), one class of nitrogenous disinfection byproducts (N-DBPs), have frequently been detected in drinking water. The cytotoxicity and genotoxicity of BANs have been demonstrated in mammalian cells. However, a systematic study of the in vivo toxicity of BANs is rare. In this study, metabolomics combined with histopathology and oxidative stress analysis were used to evaluate the toxicity of BANs in mice. The results indicated that BAN exposure induced liver and kidney injury in mice. Furthermore, the superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities decreased, and the level of malonaldehyde (MDA) increased in mice livers due to BANs exposure, which indicated that hepatic oxidative stress was induced...
February 1, 2017: Science of the Total Environment
Shaikh Nisar Ali, Mir Kaisar Ahmad, Riaz Mahmood
Sodium chlorate (NaClO3) is a widely used non-selective herbicide. It is also generated as a byproduct during disinfection of drinking water by chlorine dioxide. In the present work, the effects of NaClO3 on human erythrocytes were studied under in vitro conditions. Incubation of erythrocytes with different concentrations of NaClO3 at 37 °C for 90 min resulted in significant hemolysis. Cell lysates were prepared from NaClO3-treated and untreated (control) erythrocytes and assayed for various biochemical parameters...
October 31, 2016: Environmental Science and Pollution Research International
Sai Zheng, Jia-Chen Shi, Jian-Ying Hu, Wen-Xin Hu, Jing Zhang, Bing Shao
The reaction kinetics and transformation pathways between bisphenol F (BPF) and sodium hypochlorite were investigated at pH values ranging from 6.5 to 8.5 and with different initial concentration ratios. The reaction rate was pH- and free available chlorine (FAC)-dependent: the reaction rate at pH 8.5 was almost 10 times than that at pH 6.5. A total of 40 compounds were tentatively identified as chloro-substituted BPF and polyphenolic compounds by liquid chromatography quadrupole time-of-flight mass spectrometry operating in electrospray ionization mode (LC-ESI-Q-ToF), and 4 main byproducts were confirmed by (1)H and (13)C nuclear magnetic resonance (NMR)...
December 15, 2016: Water Research
Glen Andrew de Vera, Jurg Keller, Wolfgang Gernjak, Howard Weinberg, Maria José Farré
Ozonation is known to generate biodegradable organic matter, which is typically reduced by biological filtration to avoid bacterial regrowth in distribution systems. Post-chlorination generates halogenated disinfection byproducts (DBPs) but little is known about the biodegradability of their precursors. This study determined the effect of ozonation and biofiltration conditions, specifically ozone exposure and empty bed contact time (EBCT), on the control of DBP formation potentials in drinking water. Ozone exposure was varied through addition of H2O2 during ozonation at 1 mgO3/mgDOC followed by biological filtration using either activated carbon (BAC) or anthracite...
October 8, 2016: Water Research
Koji Kosaka, Keiko Ohkubo, Michihiro Akiba
The occurrence of six haloacetamides (HAcAms), which are a group of emerging nitrogenous disinfection byproducts, was investigated in drinking water across Japan in September 2015 and February 2016. At least one of the six HAcAms were found in all of the drinking water samples and their total concentrations ranged from 0.3 to 3.8 μg/L. The detection frequencies and concentrations of 2,2-dichloroacetamide (DCAcAm) and 2-bromo-2-chloroacetamide (BCAcAm) were the largest among the targeted HAcAm species. The total HAcAm concentrations in the raw water after chlorination ranged from 0...
October 13, 2016: Water Research
Yi Li, Chi Zhang, Danmeng Shuai, Saraschandra Naraginti, Dawei Wang, Wenlong Zhang
The challenge to achieve effective water disinfection of pathogens, especially viruses, with minimized harmful disinfection byproducts calls for a cost-effective and environmentally benign technology. Here, polymeric graphitic carbon nitride (g-C3N4), as a metal-free robust photocatalyst, was explored for the first time for its ability to inactivate viruses under visible light irradiation. MS2 with an initial concentration of 1 × 10(8) PFU/mL was completely inactivated by g-C3N4 with a loading of 150 mg/L under visible light irradiation of 360 min...
October 5, 2016: Water Research
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