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Disinfection byproduct

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)...
October 19, 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
Guilin He, Cong Li, Feilong Dong, Tuqiao Zhang, Long Chen, Leslie Cizmas, Virender K Sharma
The degradation and transformation products of 17β-estradiol (E2) by chloramines in a pilot-scale water distribution system (WDS) were investigated using varying conditions including multiple mass ratios of chlorine to nitrogen (Cl/N), changing concentrations of chloramines, and different pH and pipe materials. The degradation of E2 was complete in ≤9 h in both deionized water (DW) and in the WDS under studied conditions. When the degradation rate of E2 was compared in WDS and DW, the degradation rate was appreciably greater in the WDS than in the DW at Cl/N mass ratios of 3, 4 and 6...
September 25, 2016: Water Research
Shengkun Dong, Jinfeng Lu, Michael J Plewa, Thanh H Nguyen
Reusing wastewater in agriculture is becoming increasingly common, which necessitates disinfection to ensure reuse safety. However, disinfectants can react with wastewater constituents to form disinfection byproducts (DBPs), many of which are toxic and restrict the goal of safe reuse. Our objective was to benchmark the induction of mammalian cell cytotoxicity after ozonation against chlorination for three types of real wastewaters: municipal secondary effluent and two sources of minimally treated swine farm wastewaters...
October 21, 2016: Environmental Science & Technology
Yue E, Hui Bai, Lushi Lian, Jing Li, Ernest R Blatchley
Chloride can accumulate in chlorinated swimming pool water. Although substantial efforts have been made to examine the effects of halide ions on the formation of volatile disinfection byproducts (DBPs), most have focused on bromide. The effects of chloride ion concentration on the formation of volatile DBPs in swimming pools remain largely unstudied. In this study, chlorination of typical precursors and body fluid analogue (BFA) were investigated with variable chloride concentration and pH. The formation of three volatile DBPs (NCl3, CHCl3 and CNCHCl2) was observed to be linearly correlated with chloride concentration, both in bench experiments and in actual swimming pool water samples...
November 15, 2016: Water Research
Yi-Hsueh Chuang, Kimberly M Parker, William A Mitch
Previous research has demonstrated that the reverse osmosis and advanced oxidation processes (AOPs) used to purify municipal wastewater to potable quality have difficulty removing low molecular weight halogenated disinfection byproducts (DBPs) and industrial chemicals. Because of the wide range of chemical characteristics of these DBPs, this study developed methods to predict their degradation within the UV/H2O2 AOP via UV direct photolysis and hydroxyl radical ((•)OH) reaction, so that DBPs most likely to pass through the AOP could be predicted...
October 18, 2016: Environmental Science & Technology
Mahmut S Ersan, David A Ladner, Tanju Karanfil
Nanofiltration (NF) is a promising technology for removing precursors of disinfection byproducts (DBPs) from source waters prior to oxidant addition in water treatment. The aims of this study were to investigate (i) the removal efficiencies of N-nitrosodimethylamine (NDMA), halonitromethane (HNM), and trihalomethane (THM) precursors by NF membranes from different source water types (i.e. surface water, wastewater impacted surface water, and municipal and industrial wastewater treatment effluents), (ii) the impact of membrane type, and (iii) the effects of background water components (i...
November 15, 2016: Water Research
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
Amanda K Hohner, Kaelin Cawley, Jill Oropeza, R Scott Summers, Fernando L Rosario-Ortiz
Wildfires can greatly alter the vegetation, soils, and hydrologic processes of watersheds serving as drinking water supplies, which may negatively influence source water quality and treatment. To address wildfire impacts on treatment, a drinking water intake below a burned watershed and an upstream, unburned reference site were monitored following the High Park wildfire (2012) in the Cache la Poudre watershed of northern Colorado, USA. Turbidity, nutrients, dissolved organic matter (DOM) character, coagulation treatability, and disinfection byproduct formation were evaluated and compared to pre-fire data...
November 15, 2016: Water Research
Elizabeth M Wurtzler, David Wendell
For several decades reactive oxygen species have been applied to water quality engineering and efficient disinfection strategies; however, these methods are limited by disinfection byproduct and catalyst-derived toxicity concerns which could be improved by selectively targeting contaminants of interest. Here we present a targeted photocatalytic system based on the fusion protein StrepMiniSOG that uses light within the visible spectrum to produce reactive oxygen species at a greater efficiency than current photosensitizers, allowing for shorter irradiation times from a fully biodegradable photocatalyst...
2016: PloS One
Mehrnaz Zare Afifi, Ernest R Blatchley
Ultraviolet (UV) irradiation and chlorination are commonly used together in treatment of swimming pool water because they function as complementary disinfectants and because UV-based processes have been shown to promote photodecay of chloramines. However, UV-based treatment also has the potential to promote formation of some disinfection byproducts (DBPs). As a result, the overall effects of UV irradiation with chlorination on swimming pool chemistry remain unclear. To address this issue, a three-year study was conducted in a chlorinated, indoor swimming pool under three different operating conditions: conventional chlorination (1st year) which served as a control, chlorination augmented by MP UV irradiation (2nd year), and chlorination augmented by LP UV irradiation (3rd year)...
November 15, 2016: Water Research
Yawei Huang, Tao Zhou, Xiaohui Wu, Juan Mao
In this study, efficient degradation of sulfamethoxazole (SMX) with a high synergy factor of 14.7 was demonstrated in a sonoelectrochemical (US-EC) system adopting common Pt and graphite electrodes. It was found that the US-EC system could work effectively at broad pH range of 3-9, but would achieve good performances with appropriate electrochemical conditions at 20mA/cm(2) and 0.1M Na2SO4. Both OH attacking and the anode oxidation would be responsible for the SMX degradation in the US-EC system, while the multiple promotional roles of US would be played homogenously and heterogeneously...
August 8, 2016: Ultrasonics Sonochemistry
Elaina M Kenyon, Christopher Eklund, John C Lipscomb, Rex A Pegram
A rate for hepatic metabolism (Vmax) determined in vitro must be scaled for in vivo use in a physiologically based pharmacokinetic (PBPK) model. This requires the use of scaling factors such as mg of microsomal protein per gram of liver (MPPGL) and liver mass (FVL). Variation in MPPGL and FVL impacts variation in Vmax, and hence PBPK model-derived estimates of internal dose used in dose response analysis. The impacts of adult human variation in MPPGL and FVL on estimates of internal dose were assessed using a human PBPK model for BDCM, a water disinfection byproduct, for multiple internal dose metrics for two exposure scenarios (single 0...
September 5, 2016: Toxicology Mechanisms and Methods
Feng Wang, Baoyu Gao, Defang Ma, Qinyan Yue, Ruihua Li, Qianwen Wang
In this study, reservoir water intended for drinking water supply was treated by (i) ultrafiltration (UF) (ii) coagulation (CW) (iii) coagulation combined with ultrafiltration (CW-UF). To probe the influences of three treatment processes on disinfection byproduct (DBP) precursors in source water, the changes of dissolved organic matter (DOM) amounts and physicochemical properties, and disinfection byproduct (DBP) formation characteristics during chlorine disinfection were investigated. Both carbonaceous DBP (C-DBP) and nitrogenous DBP (N-DBP) formation and speciation were analyzed...
August 30, 2016: Environmental Science and Pollution Research International
Tingting Gong, Yuxian Tao, Qiming Xian
Iodide is widely present in drinking water sources as well as wastewater effluents. Chlorination and chloramination are the most commonly used disinfection methods. During chlorination or chloramination of drinking water/wastewater effluents, iodide may be oxidized to hypoiodous acid, which may further react with organic matter to form iodinated disinfection byproducts (DBPs). Recently, several new polar iodinated DBPs have been identified in drinking water as well as chlorinated wastewater effluents, and they have drawn increasing concerns due to their high toxicity...
November 2016: Chemosphere
Zihao Wu, Jingyun Fang, Yingying Xiang, Chii Shang, Xuchun Li, Fangang Meng, Xin Yang
The UV/chlorine process, which forms several reactive species including hydroxyl radicals (HO) and reactive chlorine species (RCS) to degrade contaminants, is being considered to be an advanced oxidation process. This study investigated the kinetics and mechanism of the degradation of trimethoprim (TMP) by the UV/chlorine process. The degradation of TMP was much faster by UV/chlorine compared to UV/H2O2. The degradation followed pseudo first-order kinetics, and the rate constant (k') increased linearly as the chlorine dosage increased from 20 μM to 200 μM and decreased as pH rose from 6...
November 1, 2016: Water Research
Wenhai Chu, Shunke Ding, Tom Bond, Naiyun Gao, Daqiang Yin, Bin Xu, Zhongqi Cao
Dichloroacetamide (DCAcAm) is an important type of nitrogenous disinfection byproduct. This study is the first to report that DCAcAm can be formed in the absence of chlorinated disinfectants (chlorine and chloramines). This can occur through reduction of three chloramphenicol (CAP) antibiotics by zero valent iron (ZVI). The effects of key experimental parameters, including reaction time, ZVI dose, pH, temperature, water type, and the presence of humic acid (HA) on the formation of DCAcAm were ascertained. The DCAcAm yields from three CAPs all presented the trend of increasing first and then decreasing with time and also increased with increasing ZVI dosage...
November 1, 2016: Water Research
Kelly D Good, Jeanne M VanBriesen
The presence of bromide in rivers does not affect ecosystems or present a human health risk; however, elevated concentrations of bromide in drinking water sources can lead to difficulty meeting drinking water disinfection byproduct (DBP) regulations. Recent attention has focused on oil and gas wastewater and coal-fired power plant wet flue gas desulfurization (FGD) wastewater bromide discharges. Bromide can be added to coal to enhance mercury removal, and increased use of bromide at some power plants is expected...
September 6, 2016: Environmental Science & Technology
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