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Enhanced formation of trihalomethane disinfection byproducts from halobenzoquinones under combined UV/chlorine conditions

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Frontiers of Environmental Science & Engineering 2022年第6期16卷 109-119页

作者： He Zhao Ching-Hua Huang Chen Zhong Penghui Du Peizhe Sun Beijing Engineering Research Center of Process Pollution Control Division of Environment Technology and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332USA State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China

Halobenzoquinones(HBQs)are highly toxic disinfection byproducts(DBPs)and are also precursors of other DBPs such as trihalomethanes(THMs).The formation of THMs from HBQs during chlorine-only and UV/chlorine processes with or without bromide was investigated *** functional theory(DFT)reactivity descriptors were also applied to predict the nucleophilic/electrophilic reactive sites on HBQs and *** results were combined to explain the different behaviors of 2,6-dichloro-1,4-benzoquinone(2,6-DCBQ)and tetrachloro-1,4-benzoquinone(TCBQ)and to propose mechanism for the promoting roles of UV and hydroxylation of HBQs in THMs *** UV/chlorine,UV significantly enhanced THMs formation from 2,6-DCBQ compared to chlorine-only,mainly due to the production of OH-DCBQ^(*).Excited 2,6-DCBQ^(*)by UV benefited nucleophilic hydrolysis to produce OH-DCBQ^(*),which favored electrophilic attack by chlorine,thereby inducing more THMs ***/chlorine modestly promoted THMs formation from TCBQ compared to *** of TCBQ and UV irradiation were both important in promoting THMs formation due to the high electrophilic property of OH-TCBQ and TCBQ^(*).Meanwhile,hydroxylation of HBQs and CHCl3 formation were enhanced at higher *** work suggested that enhanced formation of THMs from HBQs should be considered in the application of combined UV and chlorine processes.

关键词： Halobenzoquinone trihalomethane Chlorine disinfection UV irradiation Disinfection byproducts Combined UV/chlorine

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Increase in Organochlorine Contaminant Levels in Major Water Sources of the United States in Response to the Coronavirus Pandemic

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Journal of Biosciences and Medicines 2024年第5期12卷 111-143页

作者： Wendy Wilburn Sujata Guha Ryan Beni Department of Biological Sciences Tennessee State University Nashville TN USA Department of Chemistry Tennessee State University Nashville TN USA

Organochlorine contaminants, such as triclosan (TCS), are present in major water sources across the United States. These antimicrobial compounds are widely used as multipurpose ingredients in everyday consumer products. They can be ingested or absorbed through the skin and are found in human blood, breast milk, and urine samples. Studies have shown that the increased use of antimicrobial agents leads to their presence and persistence in the ecosystem, particularly in soil and watersheds. Many studies have highlighted emerging concerns associated with the overuse of TCS, including dermal irritations, a higher incidence of antibacterial-related allergies, microbial resistance, disruptions in the endocrine system, altered thyroid hormone activity, metabolism, and tumor metastasis and growth. Organochlorine contaminant exposures play a role in inflammatory responsiveness, and any unwarranted innate response could lead to adverse outcomes. The capacity of TCS and other organochlorine contaminants to induce inflammation, resulting in persistent and chronic inflammation, is linked to various pathologies, such as cardiovascular disease and several types of cancers. Chronic inflammation presents a severe consequence of exposure to these antimicrobial agents, as any changes could result in the loss of immune competence. Organochlorine contaminant levels were established by the United States Environmental Protection Agency (EPA) in 2019-2020 and have consistently increased in response to the novel coronavirus (nCoV) (COVID-19) pandemic. Our previous research examined the overuse of products containing triclosan (TCS), which led to an increase in total trihalomethane (TTHM) levels affecting the quality of our water supply. We also investigated the impact of the FDA ban that now requires pre-market approval. To comprehend the consequences of excessive antimicrobial use on water quality, we conducted an analysis of the levels of total trichloromethane (chloroform), a byproduct of

关键词： Organochlorine Contaminants Triclosan trihalomethane Chloroform Water Quality

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Effects of typical nitrogenous compounds on trihalomethanes formation and chlorine demand during drinking water chlorination

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Journal of Harbin Institute of Technology(New Series) 2010年第3期17卷 303-307页

作者：陶辉赵志伟陈卫刘成李星王花平李圭白 School of Municipal and Environmental Engineering Harbin Institute of Technology Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of EducationHohai University College of Architecture and Civil Engineering Beijing University of Technology

Glycine(Gly),cysteine(Cys),aspartic acid(Asp),leucine(Leu),lysine(Lys),and methyl amine(MA) were chosen as typical nitrogenous compounds,and the effects of them on trihalomethanes (THMs) formation and chlorine demand were performed on filtrated water. Results show that the nitrogenous compounds enhance THMs formation,and the increased levels are controlled by characteristics and the concentration of nitrogenous compounds. The increase in THMs formation follows the order of Asp(126 μg/L)>Cys(119 μg/L)>MA(106 μg/L)>Lys(97 μg/L)≈Gly(96 μg/L)>Leu(80 μg/L)(while nitrogenous compounds=1.0 mg/L,and background THMs=60 μg/L). The increase in chlorine demand is approximately proportionate to the content of nitrogenous compounds,which illustrates that the increase is mainly caused by the reaction of nitrogenous compounds with chlorine. And the increase in chlorine demand follows the order of Cys(27.8 mg/L)>Asp(22.6 mg/L)=Gly(22.6 mg/L)>Lys(21.6 mg/L)>MA(14.1 mg/L)>Leu(11.8 mg/L) (while nitrogenous compounds=1.0 mg/L,and background chorine demand=1.8 mg/L). The mechanisms of nitrogenous compounds enhancing THMs formation are summ the increase of chlorine demand raising THMs formation in reaction of NOM with chlorine,and the THMs formation in chlorination of nitrogenous compounds themselves.

关键词： nitrogenous compounds trihalomethane chlorine demand

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Formation of trihalomethanes during Seawater Chlorination

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Journal of Environmental Protection 2010年第4期1卷 456-465页

作者： Ahmed Abdel-Wahab Ahmed Khodary Nasr Bensalah 不详

The use of seawater for industrial cooling is a vital technology that poses some of the most profound environmental impact on the water quality in the Arabian Gulf. Biocide (chlorine) is added to the seawater to control biofouling of the cooling system. This added chlorine reacts with bromide and other chemicals naturally exist in the water to form a wide range of oxidants. Regrettably, reactions between the residual oxidants and natural organic matter in the water lead to formation of toxic halogenated organic compounds that have detrimental effects on the environment when they are discharged into the Gulf. This paper describes the formation of trihalomethanes (THMs) in seawater cooling systems. Results of kinetic experiments have shown that concentrations of THMs increased rapidly with time during the first half hour. Chlorination of seawater has shown significant increase in total THMs (TTHMs) and in bromoform concentrations. Rapid decrease of UV absorbance at 254 nm was also observed during seawater chlorination which is indicative of natural organic matter degradation into small organic molecules including THMs and other by-products. The increase in chlorine dose was accompanied with an increase in TTHMs and bromoform concentrations. Linear relationships between total chlorine concentration and both final TTHMs and bromoform concentrations were established. First order exponential decay and exponential associate functions were developed to correlate chlorine dose with formed THMs.

关键词： Chlorination by-Products Seawater Cooling Biocides trihalomethane Bromoform

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Haloacetic acids in swimming pool and spa water in the United States and China

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Frontiers of Environmental Science & Engineering 2014年第6期8卷 820-824页

作者： Xiaomao WANG Garcia Leal M I Xiaolu ZHANG Hongwei YANG Yuefeng XIE School of Environment State Key Joint Laboratory of Environmental Simulation and Pollution Control Tsinghua University Beijing 100084 China Department of Chemical Engineering University of Cantabria Avenida de los Castros s/n 39005 Santander Cantabria Spain Environmental Engineering Program The Pennsylvania State University 777 West Harrisburg Pike Middletown PA 17057 USA

The objective of this study is to investigate the occurrence of haloacetic acids （HAAs）, a group of disinfection byproducts, in swimming pool and spa water. The samples were collected from six indoor pools, six outdoor pools and three spas in Pennsylvania, the United States, and from five outdoor pools and nine indoor pools in Beijing, China. Five HAAs （HAA5）, including monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid were analyzed. Total chlorine, pH and total organic carbon concentration were analyzed as well. Results indicated that the levels of HAA5 in swimming pools and spas in the United States ranged from 70 to 3980μg·L^-1, with an arithmetic average at 1440μg·L^-1 and a median level at 1150μg·L^-1. These levels are much higher than the levels reported in chlorinated drinking water and are likely due to organic matters released from swimmers＇ bodies. The levels of HAA5 in swimming pools in China ranged from 13 to 332μg·L^-1, with an arithmetic average at 117μg·L^-1 and a median level at 114μg·L^-1. The lower HAA levels in swimming pools in China were due to the lower chlorine residuals. Results from this study can help water professionals to better understand the formation and stability of HAAs in chlorinated water and assess risks associated with exposures to HAAs in swimming pools and spas.

关键词： chlorination disinfection byproduct haloacetic acid swimming pool trihalomethane

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THMs Precursor Removal Efficiency from Different Wastewater Treatment Technologies Effluents

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Journal of Water Resource and Protection 2018年第7期10卷 637-653页

作者： Mohannad Qurie Loay Awad Amer Kanan Department of Environment and Earth Sciences Al-Quds University Palestine Center for Chemical and Biological Analysis Al-Quds University Palestine Basic Science Departement Faculty of Engineering Imam Abdulrahman bin Faisel University Dammam KSA

Treated wastewater is one of the critical practices of sustainable water management. In Palestinian authority region different wastewater technologies are used to produce variety of effluents that are potentially suitable for different purposes. In this study, these different treated wastewater effluents were characterized chemically, biologically, and physically. Results showed that some of these effluents neither comply with Palestinian nor with other global effluent discharge guidelines. Chemical reactivity of five different treated wastewater effluents with chlorine was measured by determining their chlorine demand and total trihalomethane formation potential (TTHMFP). Results showed that different wastewater effluents chemical reactivity with chlorine and TTHMFP is not only dependent on wastewater treatment technology but also is affected by original water source from which was the water emerged. In all cases, measured THMs superseded acceptable drinking water limits. This would indicate responsibility of high percentage of cancer, hepatic and renal diseases among the local people.

关键词： Wastewater Chlorination trihalomethane Formation Potential Effluent Hepatic Disease Renal Disease Cancer

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