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Disinfection byproduct

Jian Zheng, Tao Lin, Wei Chen
N-nitrosodiethylamine (NDEA) is one of the emerging nitrogenous disinfection byproducts with probable cytotoxicity, genotoxicity, and carcinogenesis. Its potential toxicological effects have received extensive attention but remain to be poorly understood. In this study, changes in NDEA precursors in drinking water treatment process were studied using the trial of its formation potential (FP), and the toxicity induced by NDEA to adult zebrafish was investigated. NDEA FP in the raw water of Taihu Lake ranged from 46...
October 10, 2017: Chemosphere
Roberta C H M Hofman-Caris
At first it seemed that UV processes for disinfection and advanced oxidation were "harmless", as they didn't involve the addition of "dangerous" chemicals nor seemed to result in the formation of toxic byproducts. However, recently it has become clear that also during UV processes mutagentic/genotoxic byproducts may be formed. It was found that these are nitrogen containing aromatic compounds, which are formed by the reaction of photolysis products of nitrate with (photolysis products of) natural organic matter...
2017: Advances in Experimental Medicine and Biology
Tarek Manasfi, Bruno Coulomb, Sylvain Ravier, Jean-Luc Boudenne
Organic ultraviolet (UV) filters are used in sunscreens and other personal-care products to protect against harmful effects of exposure to UV solar radiation. Little is known about the fate of UV filters in seawater swimming pools disinfected with chlorine. The present study investigated the occurrence and fate of five commonly used organic UV filters, namely dioxybenzone, oxybenzone, avobenzone, 2-ethylhexyl-4-methoxycinnamate, and octocrylene, in chlorinated seawater swimming pools. Pool samples were collected to monitor the variation of UV filter concentrations during pool opening hours...
November 7, 2017: Environmental Science & Technology
Changyong Zhang, Di He, Jinxing Ma, Wangwang Tang, T David Waite
Capacitive deionization (CDI) is considered to be one of the most promising technologies for the desalination of brackish water with low to medium salinity. In practical applications, Faradaic redox reactions occurring in CDI may have both negative and positive effects on CDI performance. In this review, we present an overview of the types and mechanisms of Faradaic reactions in CDI systems including anodic oxidation of carbon electrodes, cathodic reduction of oxygen and Faradaic ion storage and identify their apparent negative and positive effects on water desalination...
October 31, 2017: Water Research
Irina Levchuk, Juan José Rueda Márquez, Mika Sillanpää
Natural organic matter (NOM) is present in underground and surface waters. The main constituents of NOM are humic substances, with a major fraction of refractory anionic macromolecules of various molecular weights. The NOM concentration in drinking water is typically 2-10 ppm. Both aromatic and aliphatic components with carboxylic and phenolic functional groups can be found in NOM, leading to negatively charged humic substances at the pH of natural water. The presence of NOM in drinking water causes difficulties in conventional water treatment processes such as coagulation...
October 19, 2017: Chemosphere
Lin-Na Xie, Chun-Hua Huang, Dan Xu, Feng Li, Jun-Ge Zhu, Chen Shen, Bo Shao, Hui-Ying Gao, Balaraman Kalyanaraman, Ben-Zhan Zhu
Pyridinium aldoximes, which are best-known as therapeutic antidotes for organophosphorus chemical warfare nerve-agents and pesticides, have been found to markedly detoxify polyhalogenated quinones which are a class of carcinogenic intermediates and recently identified disinfection byproducts in drinking water. However, the exact chemical mechanism underlying this detoxication remains unclear. Here we demonstrate that pralidoxime can remarkably facilitate the dechlorination/hydroxylation of the highly toxic tetrachloro-1, 4-benzoquinone in two-consecutive steps to generate the much less toxic 2, 5-dichloro-3, 6-dihydroxy-1, 4-benzoquonine, with rate enhancements of up to 180,000-times...
November 2, 2017: Journal of Organic Chemistry
Ji-Hyoung Ha, Sung Hyun Kim, Hee-Min Lee, Su-Ji Kim, Hae-Won Lee
In recent years, fresh vegetables have frequently been associated with the foodborne transmission of enteric viruses, such as human norovirus (NoV). Therefore, several studies have focused on developing methods to inactivate foodborne viruses for preventing outbreaks of foodborne illnesses. Sodium hypochlorite (NaOCl) is commonly used as a disinfectant, but results in undesirable effects on the appearance and taste of foods and can generate toxic byproducts when it exceeds the allowable concentration. Here, we evaluated the efficacy of a range of NaOCl concentrations (50-1000 ppm) for reducing the amounts of human NoV (NoV GII...
October 25, 2017: Foodborne Pathogens and Disease
Litang Qin, Xin Zhang, Yuhan Chen, Lingyun Mo, Honghu Zeng, Yanpeng Liang
Several hundred disinfection byproducts (DBPs) in drinking water have been identified, and are known to have potentially adverse health effects. There are toxicological data gaps for most DBPs, and the predictive method may provide an effective way to address this. The development of an in-silico model of toxicology endpoints of DBPs is rarely studied. The main aim of the present study is to develop predictive quantitative structure-activity relationship (QSAR) models for the reactive toxicities of 50 DBPs in the five bioassays of X-Microtox, GSH+, GSH-, DNA+ and DNA-...
October 9, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
F J Vázquez-Armenta, B A Silva-Espinoza, M R Cruz-Valenzuela, G A González-Aguilar, F Nazzaro, F Fratianni, J F Ayala-Zavala
In the present study total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity and antimicrobial properties of grape (Vitis vinifera var. Red Globe) stem extract is reported. Also, the identification of main phenolic compounds was carried out by UPLC-PAD analysis. TPC and TFC of extract were 37.25 g GAE kg(-1) and 98.07 g QE kg(-1), respectively. Extract showed an antioxidant capacity of 132.60 and 317 g TE kg(-1) for DPPH and ABTS radical scavenging capacity, respectively. The main phenolic compounds identified were rutin, gallic acid, chlorogenic acid, caffeic acid, catechin and ferulic acid...
September 2017: Journal of Food Science and Technology
Jeff Kuo
A review of the literature published in 2016 on topics relating to disinfection processes is presented. This review is divided into the following sections: disinfection methods, disinfection byproducts (DBPs), and microbiology and microbial communities.
October 1, 2017: Water Environment Research: a Research Publication of the Water Environment Federation
Sophia K Chiu, Nancy C Burton, Kevin H Dunn, Marie A de Perio
In July 2015, a municipal health department in Ohio received complaints of respiratory and ocular symptoms from patrons of an indoor waterpark resort. In response, the health department conducted an online survey in August 2015 through which 19 (68%) patron and employee respondents reported eye burning, nose irritation, difficulty breathing, and vomiting. On August 11, 2015, the health department requested a health hazard evaluation by CDC's National Institute for Occupational Safety and Health to characterize the prevalence of symptoms among employees and determine the etiology of work-related symptoms...
September 22, 2017: MMWR. Morbidity and Mortality Weekly Report
Hai-Yan Wang, Ming Qin, Lei Dong, Jia-Ying Lv, Xia Wang
N-nitrosamines (NAms), which can arise as byproducts of disinfection agents, are reportedly found in drinking water, and their potential carcinogenicity is a concern; however, little research exists regarding the genotoxicity or carcinogenicity of NAms exposure as a low-dose mixture. The three most common NAms components in China's drinking water are N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA) and N-nitrosomethylethylamine (NMEA). Thus, we measured the genotoxic and carcinogenic potential of these compounds and measured the cell cycle and gene expression...
2017: International Journal of Medical Sciences
Nsikak U Benson, Oyeronke A Akintokun, Adebusayo E Adedapo
Levels of trihalomethanes (THMs) in drinking water from water treatment plants (WTPs) in Nigeria were studied using a gas chromatograph (GC Agilent 7890A with autosampler Agilent 7683B) equipped with electron capture detector (ECD). The mean concentrations of the trihalomethanes ranged from zero in raw water samples to 950 μg/L in treated water samples. Average concentration values of THMs in primary and secondary disinfection samples exceeded the standard maximum contaminant levels. Results for the average THMs concentrations followed the order TCM > BDCM > DBCM > TBM...
2017: Journal of Environmental and Public Health
Lucien W Gassie, James D Englehardt
Net-zero greywater (NZGW) reuse, or nearly closed-loop recycle of greywater for all original uses, can recover both water and its attendant hot-water thermal energy, while avoiding the installation and maintenance of a separate greywater sewer in residential areas. Such a system, if portable, could also provide wash water for remote emergency health care units. However, such greywater reuse engenders human contact with the recycled water, and hence superior treatment. The purpose of this paper is to review processes applicable to the mineralization of organics, including control of oxidative byproducts such as bromate, and maintenance of disinfection consistent with potable reuse guidelines, in NZGW systems...
November 15, 2017: Water Research
Huang Huang, Haihui Zhu, Wenhui Gan, Xue Chen, Xin Yang
A 12-month sampling program was conducted throughout a drinking water distribution system in Shenzhen and the data from 251 samples provide a comprehensive picture of the spatial and seasonal variability of 17 species disinfection by-products (DBPs) in a city with subtropical monsoon climate. The carbonaceous disinfection by-product (C-DBPs) included four trihalomethanes (THMs), three trihaloacetaldehydes (THAs) and two haloketones (HKs). Their median concentrations over the entire period were 19.9 μg/L, 3...
September 1, 2017: Chemosphere
Jinhua Li, Madlen Bauer, Birget Moe, Elaine M Leslie, Xing-Fang Li
Halobenzoquinones (HBQs) are frequently detected disinfection byproducts (DBPs) in treated water. Recent studies have demonstrated that HBQs are highly cytotoxic and capable of inducing the generation of reactive oxygen species (ROS) and depleting cellular glutathione (GSH). Multidrug resistance proteins (MRPs/ABCCs) are known to play a critical role in the elimination of numerous drugs, carcinogens, toxicants, and their conjugated metabolites. In general, little is known about the roles of transporters in DBP toxicity...
October 16, 2017: Chemical Research in Toxicology
A Ruecker, H Uzun, T Karanfil, M T K Tsui, A T Chow
Coastal blackwater rivers, characterized by high concentrations of natural organic matter, are source water for millions of people in the southeastern US. In October 2015, large areas of coastal South Carolina were flooded by Hurricane Joaquin. This so-called "thousand-year" rainfall mobilized and flushed large amounts of terrestrial organic matter and associated pollutants (e.g. mercury) into source water, affecting water quality and safety of municipal water supply. To understand the dynamics of water quality and water treatability during this extreme flood, water samples were collected from Waccamaw River (a typical blackwater river in the southeastern US) during rising limb, peak discharge, falling limb, and base flow...
August 23, 2017: Chemosphere
Daniel B Gingerich, Meagan S Mauter
Water treatment processes present intersectoral and cross-media risk trade-offs that are not presently considered in Safe Drinking Water Act regulatory analyses. This paper develops a method for assessing the air emission implications of common municipal water treatment processes used to comply with recently promulgated and proposed regulatory standards, including concentration limits for, lead and copper, disinfection byproducts, chromium(VI), strontium, and PFOA/PFOS. Life-cycle models of electricity and chemical consumption for individual drinking water unit processes are used to estimate embedded NOx, SO2, PM2...
September 7, 2017: Environmental Science & Technology
Lu Wang, Yuefei Ji, Junhe Lu, Deyang Kong, Xiaoming Yin, Quansuo Zhou
The objective of this research was to compare the transformation of Br(-) and formation of brominated byproducts in UV/persulfate (PS) and UV/H2O2 processes. It was revealed that Br(-) was efficiently transformed to free bromine which reacted with humic acid (HA) or dihydroxybenzoic acid resulting in the formation of brominated byproducts such as bromoacetic acids (BAAs) in UV/PS system. In contrast, no free bromine and brominated byproducts could be detected in UV/H2O2 system, although the oxidization of Br(-) was evident...
October 2017: Environmental Science and Pollution Research International
Guocheng Zhu, Yongning Bian, Andrew S Hursthouse, Peng Wan, Katarzyna Szymanska, Jiangya Ma, Xiaofeng Wang, Zilong Zhao
Natural organic matter (NOM) found in water sources is broadly defined as a mixture of polyfunctional organic molecules, characterized by its complex structure and paramount influence on water quality. Because the inevitable release of pollutants into aquatic environments due to an ineffective control of industrial and agricultural pollution, the evaluation of the interaction of NOM with heavy metals, nanoparticles, organic pollutants and other pollutants in the aquatic environment, has greatly increased. Three-dimensional (3-D) fluorescence has the potential to reveal the interaction mechanisms between NOM and pollutants as well as the source of NOM pollution...
November 2017: Journal of Fluorescence
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