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Hinneh KDC, Okabe J, Kosaka K, Echigo S, Itoh S. N-Nitrosodimethylamine formation from anthropogenic nitrogenous compounds during preozonation and post-chloramination with characteristic low treatment dose. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024:10.1007/s11356-024-34236-3. [PMID: 38980483 DOI: 10.1007/s11356-024-34236-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 06/30/2024] [Indexed: 07/10/2024]
Abstract
One effective option to minimize N-nitrosodimethylamine (NDMA) in finished drinking water is to identify and control its precursors. However, previous works to identify significant precursors use formation potential (FP) tests using high doses to assure the maximum NDMA formation rather than the NDMA formation in finished waters. In this study, we applied characteristic low treatment doses of ozone (O3)-to-dissolved organic carbon (DOC) of target compounds of 0.8 mg/mg and NH2Cl of 2.5 ± 0.2 mg Cl2/L to evaluate the NDMAFP yields of organic compounds bearing N,N-dimethylamine (DMA) and N,N-dimethylhydrazine (DMH) during preozonation and post-chloramination. The results in pH-buffered Milli-Q water showed a significant decrease from ≤ 52% to non-detectable levels in the O3-NDMAFP yields of O3-reactive precursors (i.e., DMH-like compounds) after preozonation and post-chloramination. Similarly, a significant decrease from 0.5 to 12% to nonquantifiable levels was observed for the NH2Cl-NDMAFP yields of NH2Cl-reactive precursors; however, the NH2Cl-NDMAFP yields of N,N-dimethylbenzylamine (DMBzA)-like compounds only decreased from ~ 110 to ≤ 43%, suggesting that these compounds could contribute to NH2Cl-NDMAFPs even after preozonation. The effect of the matrix in sewage-effluent and lake water samples varied and was specific for precursors; for example, the O3-NDMAFP yield of 1,1,1',1'-tetramethyl-4,4'-(methylene-di-p-phenylene) disemicarbazide (TMDS), an important O3-reactive NDMA precursor, did not significantly decrease when tested in sewage-effluent samples. Based on the previous occurrence concentration of TMDS in sewage samples, we estimated an NDMAFP of ~ 315 ng/L. This estimate exceeds the guidance concentrations of NDMA (3-100 ng/L), highlighting the importance of TMDS and its related compounds for NDMA formation.
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Affiliation(s)
- Klon D C Hinneh
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Nishikyo, 615-8540, Japan.
- Graduate School of Global Environmental Studies, Kyoto University, Yoshidahonmachi, Kyoto, Sakyo, 606-8501, Japan.
| | - Junki Okabe
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Nishikyo, 615-8540, Japan
| | - Koji Kosaka
- Department of Environmental Health, National Institute of Public Health, Wako, Saitama, 351-0197, Japan
| | - Shinya Echigo
- Graduate School of Global Environmental Studies, Kyoto University, Yoshidahonmachi, Kyoto, Sakyo, 606-8501, Japan
| | - Sadahiko Itoh
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Nishikyo, 615-8540, Japan
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Huang H, Chen Z, Su Y, Zeng H, Li H, Chen Y, Qi S, Chen W, Chen W, Zhang G. N-nitrosamines in electroplating and printing/dyeing industrial wastewater treatment plants: Removal efficiency, environmental emission, and the influence on drinking water. WATER RESEARCH 2024; 255:121537. [PMID: 38555784 DOI: 10.1016/j.watres.2024.121537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/04/2024] [Accepted: 03/26/2024] [Indexed: 04/02/2024]
Abstract
The discharge of industrial wastewater containing high concentrations of N-nitrosamines to the aquatic environment can impair downstream source waters and pose potential risks to human health. However, the transport and fate of N-nitrosamines in typical industrial wastewater treatment plants (IWWTPs) and the influence of these effluents on source water and drinking water are still unclear. This study investigated nine N-nitrosamines in four full-scale electroplating (E-) and printing/dyeing (PD-) IWWTPs, two drinking water treatment plants (DWTPs) in the lower reaches of these IWWTPs, and the corresponding tap water in South China. The total concentrations of N-nitrosamines (∑NAs) were 382-10,600, 480-1920, 494-789, and 27.9-427 ng/L in influents, effluents, source water, and tap water, respectively. The compositions of N-nitrosamine species in different influents varied a lot, while N-nitrosodi-n-butylamine (NDBA) and N-nitrosodimethylamine (NDMA) dominated in most of the effluents, source water, and tap water. More than 70 % N-nitrosamines were removed by wastewater treatment processes used in E-IWWTPs such as ferric-carbon micro-electrolysis (Fe/C-ME), while only about 50 % of N-nitrosamines were removed in PD-IWWTPs due to the use of chlorine reagent or other inefficient conventional processes such as flocculation by cationic amine-based polymers or bio-contact oxidation. Therefore, the mass fluxes of N-nitrosamines discharged from these industrial wastewaters to the environment in the selected two industrial towns were up to 14,700 mg/day. The results based on correlation and principal component analysis significantly demonstrated correlations between E-and PD-effluents and source water and tap water, suggesting that these effluents can serve as sources of N-nitrosamines to local drinking water systems. This study suggests that N-nitrosamines are prevalent in typical IWWTPs, which may infect drinking water systems. The findings of this study provide a basis data for the scientific evaluation of environmental processes of N-nitrosamines.
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Affiliation(s)
- Huanfang Huang
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, PR China; State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control, South China Institute of Environmental Sciences, MEE, Guangzhou 510535, PR China
| | - Zifeng Chen
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, PR China
| | - Yuru Su
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, PR China
| | - Honghu Zeng
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, PR China
| | - Haixiang Li
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, PR China
| | - Yingjie Chen
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, PR China
| | - Shihua Qi
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, PR China
| | - Wei Chen
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, PR China
| | - Wenwen Chen
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, PR China.
| | - Gan Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, PR China
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Gao M, Jiang Z, Liao X, Qi H, Zhao L, Chen C, Westerman D. NDMA formation during ozonation of DMAPA: Influencing factors, mechanisms, and new pathway exploration. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 825:153881. [PMID: 35182642 DOI: 10.1016/j.scitotenv.2022.153881] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 02/07/2022] [Accepted: 02/11/2022] [Indexed: 06/14/2023]
Abstract
Aliphatic amines, common constituents that contribute to dissolved organic nitrogen (DON), can quickly react with ozone due to the lone electron pair on the nitrogen atom and this may produce carcinogen N-Nitrosodimethylamine (NDMA). 3-(Dimethylamino)-1-propylamine (DMAPA) was chosen as a representative to elucidate the NDMA formation characteristics, kinetic rates, reaction pathways, and influencing factors during ozonation in this study. The results demonstrated that NDMA generated directly from DMAPA during ozonation. Moreover, the NDMA yields increased with ozone dosages. The NDMA molar yield increased and then decreased when the pH raised from 5 to 9, achieving the maximum value at pH 8. Hydroxyl radical (∙OH) played a promotional role in NDMA formation, and its scavenger dramatically cut down its yields. Low levels of Br- facilitated NDMA formation, while the value significantly reduced when Br- was up to 1 mM. The NDMA amount was slightly raised by NO2-, but it was inhibited by NH4+ and NO3-. Moreover, it was also depressed by co-existing components in actual lake water. Based on the result of the Gaussian calculation, the LC-MS/MS and GC-MS analysis, four possible transformation pathways were proposed. The radical recombination was verified to be the primary pathway for ozone promoting NDMA formation from DMAPA.
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Affiliation(s)
- Menglan Gao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Fujian 361021, China
| | - Zhibin Jiang
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Fujian 361021, China
| | - Xiaobin Liao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Fujian 361021, China.
| | - Huan Qi
- College of Textiles and Appearl, Quanzhou Normal University, Fujian 362002, China
| | - Lei Zhao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Fujian 361021, China
| | - Chao Chen
- School of Environment, Tsinghua University, Beijing 100082, China.
| | - Danielle Westerman
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, United States
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Song Y, Feng S, Qin W, Li J, Guan C, Zhou Y, Gao Y, Zhang Z, Jiang J. Formation mechanism and control strategies of N-nitrosodimethylamine (NDMA) formation during ozonation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 823:153679. [PMID: 35131246 DOI: 10.1016/j.scitotenv.2022.153679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 01/06/2022] [Accepted: 01/31/2022] [Indexed: 06/14/2023]
Abstract
This review summarizes major findings over the last decade related to N-nitrosodimethylamine (NDMA) formed upon ozonation, which was regarded as highly toxic and carcinogenic disinfection by-products. The reaction kinetics, chemical yields and mechanisms were assessed for the ozonation of potential precursors including dimethylamine (DMA), N,N-dimethylsulfamide, hydrazines, N-containing water and wastewater polymers, dyes containing a dimethylamino function, N-functionalized carbon nanotubes, guanidine, and phenylurea. The effects of bromide on the NDMA formation during ozonation of different types of precursors were also discussed. The mechanism for NDMA formation during ozonation of DMA was re-summarized and new perspectives were proposed to assess on this mechanism. Effect of hydroxyl radicals (•OH) on NDMA formation during ozonation was also discussed due to the noticeable oxidation of NDMA by •OH. Surrogate parameters including nitrate formation and UV254 after ozonation may be useful parameters to estimate NDMA formation for practical application. The strategies for NDMA formation control were proposed through improving the ozonation process such as ozone/hydrogen peroxide, ozone/peroxymonosulfate and catalytic ozonation process based on membrane pores aeration (MEMBRO3X).
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Affiliation(s)
- Yang Song
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Sha Feng
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Wen Qin
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Juan Li
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Chaoting Guan
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Yang Zhou
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Yuan Gao
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Zhong Zhang
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Jin Jiang
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China.
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Lim S, Shi JL, von Gunten U, McCurry DL. Ozonation of organic compounds in water and wastewater: A critical review. WATER RESEARCH 2022; 213:118053. [PMID: 35196612 DOI: 10.1016/j.watres.2022.118053] [Citation(s) in RCA: 99] [Impact Index Per Article: 49.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 01/05/2022] [Accepted: 01/08/2022] [Indexed: 06/14/2023]
Abstract
Ozonation has been applied in water treatment for more than a century, first for disinfection, later for oxidation of inorganic and organic pollutants. In recent years, ozone has been increasingly applied for enhanced municipal wastewater treatment for ecosystem protection and for potable water reuse. These applications triggered significant research efforts on the abatement efficiency of organic contaminants and the ensuing formation of transformation products. This endeavor was accompanied by developments in analytical and computational chemistry, which allowed to improve the mechanistic understanding of ozone reactions. This critical review assesses the challenges of ozonation of impaired water qualities such as wastewaters and provides an up-to-date compilation of the recent kinetic and mechanistic findings of ozone reactions with dissolved organic matter, various functional groups (olefins, aromatic compounds, heterocyclic compounds, aliphatic nitrogen-containing compounds, sulfur-containing compounds, hydrocarbons, carbanions, β-diketones) and antibiotic resistance genes.
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Affiliation(s)
- Sungeun Lim
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf CH-8600, Switzerland
| | - Jiaming Lily Shi
- Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA, United States
| | - Urs von Gunten
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf CH-8600, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland.
| | - Daniel L McCurry
- Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA, United States.
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Shen L, Chen Z, Kang J, Yan P, Shen J, Wang B, Zhao S, Bi L, Wang S, Cheng Y. N-nitrosodimethylamine formation during oxidation of N,N-dimethylhydrazine compounds by peroxymonosulfate: Kinetics, reactive species, mechanism and influencing factors. JOURNAL OF HAZARDOUS MATERIALS 2022; 428:128191. [PMID: 35033910 DOI: 10.1016/j.jhazmat.2021.128191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 12/05/2021] [Accepted: 12/29/2021] [Indexed: 06/14/2023]
Abstract
This study found that peroxymonosulfate (PMS) oxidation without activation has the potential to generate a suspected human carcinogen, N-nitrosodimethylamine (NDMA), in water containing N,N-dimethylhydrazine compounds. Considerable amounts of NDMA formed from three compounds by PMS oxidation were observed. 1,1,1',1'-Tetramethyl-4,4'-(methylene-di-p-phenylene) disemicarbazide (TMDS), which is an industrial antiyellowing agent and light stabilizer, was used as a representative to elucidate the kinetics, transformation products, mechanism and NDMA formation pathways of PMS oxidation. TMDS degradation and NDMA formation involved direct PMS oxidation and singlet oxygen (1O2) oxidation. The oxidation by PMS/1O2 was pH-dependent, which was related to the pH-dependent characteristics of the reactive oxygen species and intermediates. The degradation mechanism of TMDS mainly included the side chain cleavage, dealkylation, and O-addition. NDMA was generated from TMDS mainly via O-addition and 1,1-dimethylhydrazine (UDMH) generation. The cleavage of amide nitrogen in O-addition products and primary amine nitrogen in UDMH are likely the key steps in NDMA generation. The results emphasized that the formation of harmful by-products should be taken into account when assessing the feasibility of PMS oxidation.
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Affiliation(s)
- Linlu Shen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Zhonglin Chen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Jing Kang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Pengwei Yan
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Jimin Shen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Binyuan Wang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Shengxin Zhao
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Lanbo Bi
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Shuyu Wang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Yizhen Cheng
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
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Hinneh KDC, Kosaka K, Echigo S, Itoh S. Predictable Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry Fragmentation of Ozone-Reactive N-Nitrosodimethylamine Precursors Coupled with In Silico Fragmentation and Ion Mobility-Quadrupole Time-of-Flight Facilitates Their Identification in Sewage. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:2345-2354. [PMID: 35119842 DOI: 10.1021/acs.est.1c05888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
This study investigated the liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF/MS) fragmentation of 10 potent model ozone (O3)-reactive N-nitrosodimethylamine (NDMA) precursors bearing (CH3)2N-N or (CH3)2N-(SO2)-N. Fragments (m/z 61.0766, 60.0688 Da loss, and 72.0688 Da loss) were discovered as pertinent diagnostic fragments for precursors bearing (CH3)2N-N, whereas a loss of 108.0119 Da was consistent for precursors bearing (CH3)2N-S(O2)-N. Using the fragments as structural hints on a sewage fraction with a high concentration of O3-reactive precursors, peaks of precursors sharing m/z 61.0766, a 60.0688 Da loss, or both were flagged. Then, using in silico fragmenters and (CH3)2N-N as a substructure filter on online-chemical structure databases, we identified PubChem's compound identifier (PCCID) 141210417 and 1,1,1',1'-tetramethyl-4,4'-(methylene-di-p-phenylene)disemicarbazide (TMDS). TMDS was confirmed using an authentic standard, and ion mobility (IM)-QTOF/MS confirmed its rider peak as PCCID 141210417. PCCID 141210417 is an isomer of TMDS, and its environmental occurrence is associated with technical-grade TMDS and industrial effluents. The estimated contribution of TMDS to the total NDMA formation potential of the sewage fraction was 20-24%, which was suggestive of the significance of PCCID 141210417 and other precursors.
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Affiliation(s)
- Klon D C Hinneh
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Koji Kosaka
- Department of Environmental Health, National Institute of Public Health, Wako, Saitama 351-0197, Japan
| | - Shinya Echigo
- Department of Global Environmentally-Friendly Industries for Sustainable Development, Graduate School of Global Environmental Studies, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan
| | - Sadahiko Itoh
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8540, Japan
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Liao X, Shen L, Jiang Z, Gao M, Qiu Y, Qi H, Chen C. NDMA formation during ozonation of metformin: Roles of ozone and hydroxyl radicals. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 796:149010. [PMID: 34280626 DOI: 10.1016/j.scitotenv.2021.149010] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 07/05/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
Metformin, a high-consumed pharmaceutical for diabetes, has been reported to generate carcinogenic nitroso-dimethylamine (NDMA) during treatment of its containing wastewater. However, whether it would produce NDMA during ozonation or not is unclear, let alone discriminate roles of ozone (O3) and hydroxyl radicals (OH). In this paper, effects of ozonation on NDMA formation from metformin were investigated, roles of O3 and OH were also distinguished by adding tert-butyl alcohol (tBA) as OH scavenger. Moreover, various influencing factors and reaction mechanisms were demonstrated. The results indicated that NDMA could be directly formed from metformin during ozonation, the addition of OH scavenger significantly enhanced its formation (0-46.2 ng/L vs 0-139.1 ng/L). The formation of NDMA by O3 and OH was more affected by bromide and HCO3- than those with only O3; while the impacts of pH and sulphate on the latter were more notable. No matter without/with tBA in the solution, the formed NDMA during ozonation of metformin increased with raising pH (from 5 to 9) and achieved the maximum 69.6 ng/L and 235.9 ng/L at pH 9, respectively; small amount of bromide (0.1 μM) promoted NDMA production, high levels of bromide (10 μM) inhibited its formation; the existence of HCO3- enhanced the amounts of NDMA from 44.5 to 73.5 ng/L (raised by 65.2%) by O3 and OH and from 102.9 to 130 ng/L with only O3 (raised by 26.3%); with the addition of sulphate, NDMA concentration raised by 43.8% by O3 and OH, while the value was high up to 134.6% with only O3. Based on the result of UPLC-Q-TOF and density functional theory, the oxidation intermediates were identified and possible transformation pathways of metformin during ozonation were proposed. The findings in this paper would provide reference when treating metformin-containing water in future.
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Affiliation(s)
- Xiaobin Liao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Fujian 361021, China.
| | - Linlu Shen
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Fujian 361021, China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 195000, China
| | - Zhibin Jiang
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Fujian 361021, China
| | - Menglan Gao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Fujian 361021, China
| | - Yu Qiu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Huan Qi
- College of Textiles and Apparel, Quanzhou Normal University, Fujian 362002, China
| | - Chao Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
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Wolff D, Helmholz L, Castronovo S, Ghattas AK, Ternes TA, Wick A. Micropollutant transformation and taxonomic composition in hybrid MBBR - A comparison of carrier-attached biofilm and suspended sludge. WATER RESEARCH 2021; 202:117441. [PMID: 34343873 DOI: 10.1016/j.watres.2021.117441] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 06/24/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
The suspended sludge and carrier-attached biofilms of three different hybrid moving bed biofilm reactor (MBBR) systems were investigated with respect to their transformation potential for a broad range of micropollutants (MPs) as well as their microbial community composition. For this purpose, laboratory-scale batch experiments were conducted with the separated suspended sludge and the carrier-attached biofilm of every system in triplicate. For all batches the removal of 31 MPs as well as the composition of the microbial community were analyzed. The carrier-attached biofilms from two hybrid MBBR systems showed a significant higher overall transformation potential in comparison to the respective suspended sludge. Especially for the MPs trimethoprim, diclofenac, mecoprop, climbazole and the human metabolite 10,11-dihydro-10-hydroxycarbamazepine consistently higher pseudo-first-order transformation rates could be observed in all three systems. The analysis of the taxonomic composition revealed taxa showing higher relative abundances in the carrier-attached biofilms (e. g. Nitrospirae and Chloroflexi) and in the suspended biomasses (e. g. Bacteroidetes and Betaproteobacteria). Correlations of the biodiversity indices and the MP biotransformation rates resulted in significant positive associations for 11 compounds in suspended sludge, but mostly negative associations for the carrier-attached biofilms. The distinct differences in MP removal between suspended sludge and carrier-attached biofilm of the three different MBBR systems were also reflected by a statistically significant link between the occurrence of specific bacterial taxa (Acidibacter, Nitrospira and Rhizomicrobium) and MP transformation rates of certain MPs. Even though the identified correlations might not necessarily be of causal nature, some of the identified taxa might serve as suitable indicators for the transformation potential of suspended sludge or carrier-attached biofilms.
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Affiliation(s)
- David Wolff
- Federal Institute of Hydrology (BfG), D-56068 Koblenz, Am Mainzer Tor 1, Germany
| | - Lissa Helmholz
- Federal Institute of Hydrology (BfG), D-56068 Koblenz, Am Mainzer Tor 1, Germany
| | - Sandro Castronovo
- Federal Institute of Hydrology (BfG), D-56068 Koblenz, Am Mainzer Tor 1, Germany
| | - Ann-Kathrin Ghattas
- Federal Institute of Hydrology (BfG), D-56068 Koblenz, Am Mainzer Tor 1, Germany
| | - Thomas A Ternes
- Federal Institute of Hydrology (BfG), D-56068 Koblenz, Am Mainzer Tor 1, Germany
| | - Arne Wick
- Federal Institute of Hydrology (BfG), D-56068 Koblenz, Am Mainzer Tor 1, Germany.
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Qiu Y, Bei E, Li X, Xie S, Xiao H, Luo Y, Wang Y, Wang J, Zhang X, Chen C. Quantitative analysis of source and fate of N-nitrosamines and their precursors in an urban water system in East China. JOURNAL OF HAZARDOUS MATERIALS 2021; 415:125700. [PMID: 34088188 DOI: 10.1016/j.jhazmat.2021.125700] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
The source and fate of N-nitrosamines and their precursors in terms of formation potential (FP) was investigated quantitatively in the city level for the first time. Different sources of nitrosamines and their precursors were investigated in one city in the Yangtze River delta, China. The source water located downstream of the city contained 8.4 ng/L of N-nitrosodimethyamine (NDMA) and 153 ng/L of NDMA FP. The contribution of each discharge source was evaluated based on the concentration, the river water flux, and the amount of wastewater discharges. Textile printing and dyeing wastewater, and electroplating industrial wastewater contained high concentration of nitrosamines and were important discharge sources. Taking NDMA and NDMA FP attenuation by photolysis and biodegradation into consideration, the mass load calculation showed upstream surface water brought about 13 ± 4% of NDMA and 21 ± 3% of NDMA FP to downstream source water. Local wastewater discharges contributed 30 ± 8% of NDMA and 17 ± 2% of NDMA FP to downstream source water. Endogenous formation via amino acids metabolism could contribute 36% of NDMA FP (maximum) to downstream source water. Overall, this study provides a protocol for quantitative evaluation of the nitrosamine contribution to urban water supply from different contamination sources.
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Affiliation(s)
- Yu Qiu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China, 100084
| | - Er Bei
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China, 100084
| | - Xiao Li
- Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou, China, 215163
| | - Shuguang Xie
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China, 100871
| | - Hao Xiao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China, 100084
| | - Yihua Luo
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China, 100084
| | - Yu Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China, 100084; School of Resources and Environment, China University of Geosciences (Beijing), Beijing, China, 100083
| | - Jun Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China, 100084; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou, China, 215163
| | - Xiaojian Zhang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China, 100084; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou, China, 215163
| | - Chao Chen
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China, 100084; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou, China, 215163.
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Wang W, Yang P, Guo Y, Ji H, Liang F. Phenylurea herbicide degradation and N-nitrosodimethylamine formation under various oxidation conditions: Relationships and transformation pathways. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 269:116122. [PMID: 33248834 DOI: 10.1016/j.envpol.2020.116122] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 11/11/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
Four phenylurea herbicides (PUHs) were assessed for degradation and transformation into N-nitrosodimethylamine (NDMA) under three oxidation conditions (chlorine (Cl2), chlorine dioxide (ClO2), and ozone (O3)) from an aqueous solution. Removal ratios correlated with the numbers of halogen elements contained in PUHs (isoproturon (0) > chlorotoluron (1 Cl) > diuron (2 Cl) > fluometuron (3 F)), and the degradation efficiencies of oxidants from fastest to slowest were: O3, ClO2, and Cl2. NDMA can be generated directly from the ozonation of PUHs. Further, compared with chloramination alone, ozonation prominently promoted NDMA formation potential (NDMA-FP) during post-chloramination, and NDMA-FPs increased approximately 23-68 times than those during ozonation only at 2.5 mg/L O3 over 10 min; molar yields of NDMA from highest to lowest were 11.1% (isoproturon), 1.17% (chlorotoluron), 1.0% (diuron), and 0.73% (fluometuron). The PUH degradation kinetics data during ozonation agreed with the pseudo-first-order model. The rate constant kobs were 0.31 × 10-3-19.8 × 10-3 s-1. The kobs and removal ratios of PUHs during ozonation partially scaled with the mass, LogKow, and Henry's constants of PUHs. Comparisons of measured NDMA-FPs with calculated NDMA-FPs from residual PUH after oxidation showed that the intermediates produced during ozonation facilitated NDMA-FPs; this contribution was also observed for chlorotoluron and isoproturon during ClO2 oxidation. Examination of reaction mechanisms revealed that tertiary amine ozonation, N-dealkylation, hydroxylation, the cleavage of N-C bonds, ammonification, and nitrification occurred during the ozonation of PUHs, and the dimethylamine (DMA) functional groups could be decomposed directly and transformed into NDMA via the formation of the intermediate unsymmetrical dimethylhydrazine. NDMA is also formed from the reaction between DMA and phenylamino-compounds. Clarifying primary degradation products of PUHs and transformation pathways of NDMA during oxidation processes is useful to optimize treatment processes for water supplies.
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Affiliation(s)
- Wanfeng Wang
- Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, School of Environment, Henan Normal University, Xinxiang, 453007, China.
| | - Panqing Yang
- Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, School of Environment, Henan Normal University, Xinxiang, 453007, China
| | - Yanling Guo
- College of Resource and Environment, Henan Institute of Science and Technology, Xinxiang, 453003, China
| | - Haoran Ji
- Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, School of Environment, Henan Normal University, Xinxiang, 453007, China
| | - Fang Liang
- Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, School of Environment, Henan Normal University, Xinxiang, 453007, China
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12
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Rykowska I, Andrzejewski P, Wolski R, Dabrowska A. Dimethylamine oxidation by homogenic (Fe+2 and UV) and heterogenic (CuO) activated peroxydisulfate. CHEMICAL PAPERS 2020. [DOI: 10.1007/s11696-020-01354-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AbstractOxidation of water or wastewaters with classical oxidants such as chloramine, chlorine dioxide, ozone or permanganate may lead to formation of carcinogenic N-nitrosodimethylamine (NDMA), when dimethylamine (DMA) is present as water pollution. This study shows that peroxydisulfate (PDS) could be considered as relatively ‘safe’ oxidant as PDS partly destroys dimethylamine without formation of NDMA. Prior to use, peroxydisulfate was activated. Metal ions Fe+2, UV radiation and metal oxides CuO were compared as activator compounds to understand their efficiency in PDS systems (radical and non-radical) for oxidation of DMA. The amount of nitrate formed as the result of nitrogen oxidation, as well as formaldehyde (FA), formed as the result of methyl groups oxidation, was monitored as an indicator of DMA degradation. Application studies conducted on natural water showed that activated peroxydisulfate can effectively protect against the undesirable NDMA formation.
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Chen W, Chen Y, Huang H, Lu Y, Khorram MS, Zhao W, Wang D, Qi S, Jin B, Zhang G. Occurrence of N-Nitrosamines in the Pearl River delta of China: Characterization and evaluation of different sources. WATER RESEARCH 2019; 164:114896. [PMID: 31377526 DOI: 10.1016/j.watres.2019.114896] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/25/2019] [Accepted: 07/21/2019] [Indexed: 06/10/2023]
Abstract
N-nitrosamines in water have drawn significant concerns for the health of water consumers due to their carcinogenic properties. N-nitrosamines are formed during disinfection of wastewater as well as different industrial and agricultural processes. This study characterized the N-nitrosamines compositions in eleven different wastewaters in the Pearl River Delta (PRD) in Southeast China, and the spatial distributions and the abundances of N-nitrosamines in the Pearl River water were detected. The results indicated that five N-nitrosamines species, including N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosopyrrolidine (NPYR), N-nitrosomorpholine (NMOR) and N-nitrosodibutylamine (NDBA) were found in the industrial wastewater samples in the PRD. Remarkably high concentrations of NDMA (up to 4000 ng/L) were found in the wastewaters from the textile printing and dyeing as well as the electroplating, whereas NDMA, NDEA and NMOR were detected in the domestic wastewaters at concentrations lower than 15 ng/L. Moreover, we found that certain treatment processes for the electroplating wastewater could form a significant amount of NDMA, NPYR and NMOR. Analyses of the Pearl River water samples showed occurrences of different N-nitrosamines species, including NDMA (5.7 ng/L), NDEA (1.7 ng/L), NPYR (2.2 ng/L), NMOR (2.2 ng/L) and NDBA (4.9 ng/L). The abundances of N-nitrosamines species varied spatially due to the inputs from the different sources. Thus, our study provides unique and valuable information for occurrences, abundances and source characteristics of N-nitrosamines in the PRD.
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Affiliation(s)
- Wenwen Chen
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China
| | - Yingjie Chen
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, China; School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Huanfang Huang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Yijin Lu
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China
| | - Mahdi Safaei Khorram
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Wenyu Zhao
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China
| | - Dunqiu Wang
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China
| | - Shihua Qi
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, China; School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Biao Jin
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
| | - Gan Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
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Shen L, Liao X, Qi H, Zhao L, Li F, Yuan B. NDMA formation from 4,4'-hexamethylenebis (HDMS) during ozonation: influencing factors and mechanisms. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:1584-1594. [PMID: 30443725 DOI: 10.1007/s11356-018-3684-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 11/05/2018] [Indexed: 06/09/2023]
Abstract
N-nitrosodimethylamine (NDMA), a toxic disinfection byproduct commonly associated with chloramination, has recently been found to form from an anti-yellowing agent (4,4'-hexamethylenebis (1,1-dimethylsemicarbazide) (HDMS)) during ozonation but the mechanisms are unclear. In this paper, the potential roles of molecular ozone (O3) and hydroxyl radical (∙OH) on NDMA formation from HDMS were investigated under various oxidation conditions (ozone dosages, pH) and different components in water (bromide ion (Br-), bicarbonate ion (HCO3-), sulfate ion (SO42-), and humic acid (HA), as well as natural organic matter (NOM) from a lake). Moreover, HDMS transformation pathways by ozonation were determined. The results indicated that the formation of NDMA was enhanced through the combined effect of O3 and ∙OH compared to that by O3 alone (addition of tert-butyl alcohol (tBA) as ∙OH scavenger). ∙OH itself cannot generate NDMA directly; however, it can transform HDMS to intermediates with higher NDMA yield than parent compound. The NDMA generation was affected (small dosages promoted but high dosages inhibited) by HA or Br- no matter with or without tBA. The presence of SO42- and HCO3- ions lowered NDMA formation through ∙OH scavenging effect. Increasing pH not only increased degradation rate constant by enhancing ∙OH generation but also affected HDMS dissociation ratio, reaching the maximum NDMA formation at pH 7-8. Natural constituents in selected water matrix inhibited NDMA formation. Impacts of these influencing factors on NDMA formation by only O3 however were significantly less pronounced over that by the joint roles of O3 and ∙OH. Based on the result of Q-TOF, LC/MS/MS, and GC/MS, the possible transformation pathways of HDMS by ozonation were proposed. The NDMA enhancement mechanism by the combined effect of O3 and ∙OH can be attributed to greater amounts of intermediates with higher NDMA yield (such as unsymmetrical dimethylhydrazine (UDMH)) produced. These findings provide new understanding of NDMA formation upon ozonation of typical amine-based compounds.
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Affiliation(s)
- Linlu Shen
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, Fujian, China
| | - Xiaobin Liao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, Fujian, China.
| | - Huan Qi
- College of Textiles and Appearl, Quanzhou Normal University, Quanzhou, 362002, Fujian, China
| | - Lei Zhao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, Fujian, China
| | - Fei Li
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, Fujian, China
| | - Baoling Yuan
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, Fujian, China
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15
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Sharma A, Ahmad J, Flora SJS. Application of advanced oxidation processes and toxicity assessment of transformation products. ENVIRONMENTAL RESEARCH 2018; 167:223-233. [PMID: 30055452 DOI: 10.1016/j.envres.2018.07.010] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 06/09/2018] [Accepted: 07/05/2018] [Indexed: 05/03/2023]
Abstract
Advanced Oxidation Processes (AOPs) are the techniques employed for oxidation of various organic contaminants in polluted water with the objective of making it suitable for human consumption like household and drinking purpose. AOPs use potent chemical oxidants to bring down the contaminant level in the water. In addition to this function, these processes are also capable to kills microbes (as disinfectant) and remove odor as well as improve taste of the drinking water. The non-photochemical AOPs methods include generation of hydroxyl radical in absence of light either by ozonation or through Fenton reaction. The photochemical AOPs methods use UV light along with H2O2, O3 and/or Fe+2 to generate reactive hydroxyl radical. Non-photochemical method is the commonly used whereas, photochemical method is used when conventional O3 and H2O2 cannot completely oxidize organic pollutants. However, the choice of AOPs methods is depended upon the type of contaminant to be removed. AOPs cause loss of biological activity of the pollutant present in drinking water without generation of any toxicity. Conventional ozonation and AOPs can inactivate estrogenic compounds, antiviral compounds, antibiotics, and herbicides. However, the study of different AOPs methods for the treatment of drinking water has shown that oxidation of parent compound can also lead to the generation of a degradation/transformation product having biological activity/chemical toxicity similar to or different from the parent compound. Furthermore, an increased toxicity can also occur in AOPs treated drinking water. This review discusses various methods of AOPs, their merits, its application in drinking water treatment, the related issue of the evolution of toxicity in AOPs treated drinking water, biocatalyst, and analytical methods for identification of pollutants /transformed products and provides future directions to address such an issue.
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Affiliation(s)
- Abha Sharma
- National Institute of Pharmaceutical Education and Research, Shree Bhawani Paper Mill Road, ITI Compound, Raebareli 229010, Uttar Pradesh, India
| | - Javed Ahmad
- National Institute of Pharmaceutical Education and Research, Shree Bhawani Paper Mill Road, ITI Compound, Raebareli 229010, Uttar Pradesh, India
| | - S J S Flora
- National Institute of Pharmaceutical Education and Research, Shree Bhawani Paper Mill Road, ITI Compound, Raebareli 229010, Uttar Pradesh, India.
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Zou R, Liao X, Zhao L, Yuan B. Reduction of N-nitrosodimethylamine formation from ranitidine by ozonation preceding chloramination: influencing factors and mechanisms. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:13489-13498. [PMID: 29492817 DOI: 10.1007/s11356-018-1470-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 02/02/2018] [Indexed: 06/08/2023]
Abstract
Formation of toxic N-nitrosodimethylamine (NDMA) by chloramination of ranitidine, a drug to block histamine, was still an ongoing issue and posed a risk to human health. In this study, the effect of ozonation prior to chloramination on NDMA formation and the transformation pathway were determined. Influencing factors, including ozone dosages, pH, hydroxyl radical scavenger, bromide, and NOM, were studied. The results demonstrated that small ozone dosage (0.5 mg/L) could effectively control NDMA formation from subsequent chloramination (from 40 to 0.8%). The NDMA molar conversion was not only influenced by pH but also by ozone dosages at various pre-ozonation pH (reached the highest value of 5% at pH 8 with 0.5 mg/L O3 but decreased with the increasing pH with 1 mg/L O3). The NDMA molar yield by chloramination of ranitidine without pre-ozonation was reduced by the presence of bromide ion due to the decomposition of disinfectant. However, due to the formation of brominated intermediate substances (i.e., dimethylamine (DMA), dimethyl-aminomethyl furfuryl alcohol (DFUR)) with higher NDMA molar yield than their parent substances, more NDMA was formed than that without bromide ion upon ozonation. Natural organic matter (NOM) and hydroxyl radical scavenger (tert-butyl alcohol, tBA) enhanced NDMA generation because of the competition of ozone and more ranitidine left. The NDMA reduction mechanism by pre-ozonation during chloramination of ranitidine may be due to the production of oxidation products with less NDMA yield (such as DMA) than parent compound. Based on the result of Q-TOF and GC-MS/MS analysis, three possible transformation pathways were proposed. Different influences of oxidation conditions and water quality parameters suggest that strategies to reduce NDMA formation should vary with drinking water sources and choose optimal ozone dosage.
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Affiliation(s)
- Rusen Zou
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, China
| | - Xiaobin Liao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, China.
| | - Lei Zhao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, China
| | - Baoling Yuan
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, China.
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Sgroi M, Vagliasindi FGA, Snyder SA, Roccaro P. N-Nitrosodimethylamine (NDMA) and its precursors in water and wastewater: A review on formation and removal. CHEMOSPHERE 2018; 191:685-703. [PMID: 29078192 DOI: 10.1016/j.chemosphere.2017.10.089] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 10/05/2017] [Accepted: 10/14/2017] [Indexed: 06/07/2023]
Abstract
This review summarizes major findings over the last decade related to N-Nitrosodimethylamine (NDMA) in water and wastewater. In particular, the review is focused on the removal of NDMA and of its precursors by conventional and advanced water and wastewater treatment processes. New information regarding formation mechanisms and precursors are discussed as well. NDMA precursors are generally of anthropogenic origin and their main source in water have been recognized to be wastewater discharges. Chloramination is the most common process that results in formation of NDMA during water and wastewater treatment. However, ozonation of wastewater or highly contaminated surface water can also generate significant levels of NDMA. Thus, NDMA formation control and remediation has become of increasing interest, particularly during treatment of wastewater-impacted water and during potable reuse application. NDMA formation has also been associated with the use of quaternary amine-based coagulants and anion exchange resins. UV photolysis with UV fluence far higher than typical disinfection doses is generally considered the most efficient technology for NDMA mitigation. However, recent studies on the optimization of biological processes offer a potentially lower-energy solution. Options for NDMA control include attenuation of precursor materials through physical removal, biological treatment, and/or deactivation by application of oxidants. Nevertheless, NDMA precursor identification and removal can be challenging and additional research and optimization is needed. As municipal wastewater becomes increasingly used as a source water for drinking, NDMA formation and mitigation strategies will become increasingly more important. The following review provides a summary of the most recent information available.
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Affiliation(s)
- Massimiliano Sgroi
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125, Catania, Italy.
| | - Federico G A Vagliasindi
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125, Catania, Italy
| | - Shane A Snyder
- Department of Chemical & Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, AZ, 85721, USA; National University of Singapore, NUS Environmental Research Institute (NERI), 5A Engineering Drive 1; T-Lab Building, #02-01, 117411, Singapore
| | - Paolo Roccaro
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125, Catania, Italy
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Spahr S, von Gunten U, Hofstetter TB. Carbon, Hydrogen, and Nitrogen Isotope Fractionation Trends in N-Nitrosodimethylamine Reflect the Formation Pathway during Chloramination of Tertiary Amines. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:13170-13179. [PMID: 29032675 DOI: 10.1021/acs.est.7b03919] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Assessing the precursors and reactions leading to the carcinogenic N-nitrosodimethylamine (NDMA) during drinking water disinfection is a major challenge. Here, we investigate whether changes of 13C/12C, 2H/1H, and 15N/14N ratios of NDMA give rise to isotope fractionation trends that can be used to infer NDMA formation pathways. We carried out compound-specific isotope analysis (CSIA) of NDMA during chloramination of four tertiary amines that produce NDMA at high yields, namely ranitidine, 5-(dimethylaminomethyl)furfuryl alcohol, N,N-dimethylthiophene-2-methylamine, and N,N-dimethylbenzylamine. Carbon and hydrogen isotope ratios of NDMA function as fingerprints of the N(CH3)2 moiety and exhibit only minor isotope fractionation during the disinfection process. Nitrogen isotope ratios showed that NH2Cl is the source of the N atom of the nitroso group. The large enrichment of 15N in NDMA was indicative of the isotope effects pertinent to bond-cleavage and bond-formation reactions during chloramination of the tertiary amines. Correlation of δ15N versus δ13C values of NDMA resulted in trend lines that were not affected by the type of tertiary amine and treatment conditions, suggesting that the observed C and N isotope fractionation in NDMA may be diagnostic for NDMA precursors and formation pathways during chloramination.
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Affiliation(s)
- Stephanie Spahr
- Eawag, Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf, Switzerland
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Federale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
| | - Urs von Gunten
- Eawag, Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf, Switzerland
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Federale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich , CH-8092 Zürich, Switzerland
| | - Thomas B Hofstetter
- Eawag, Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich , CH-8092 Zürich, Switzerland
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Gushgari AJ, Halden RU, Venkatesan AK. Occurrence of N-nitrosamines in U.S. freshwater sediments near wastewater treatment plants. JOURNAL OF HAZARDOUS MATERIALS 2017; 323:109-115. [PMID: 27067539 DOI: 10.1016/j.jhazmat.2016.03.091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 03/28/2016] [Accepted: 03/30/2016] [Indexed: 06/05/2023]
Abstract
In the present study, 40 freshwater sediments collected near 14 wastewater treatment plants (WWTPs) across the United States were analyzed for eight N-nitrosamines by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Three N-nitrosamines were detected for the first time in freshwater sediments in units of ng/g dry weight at the specified detection frequency: N-nitrosodibutylamine (NDBA; 0.2-3.3; 58%), N-nitrosodiphenylamine (NDPhA; 0.2-4.7; 50%), and N-nitrosopyrrolidine (NPYR; 3.4-19.6; 18%). At least one N-nitrosamine was detected in 70% (28/40) of sediments analyzed. Non-detect values in units of ng/g dw were obtained for N-nitrosodimethylamine (NDMA; <10.2), N-nitrosomethylethylamine (NMEA; <1.7), N-nitrosodiethylamine (NDEA; <3.9), N-nitroso-di-n-propylamine (NDPA; <1.7), and N-nitrosopiperidine (NPIP; <3.6). Principal component analysis specifically points to two of multiple potential pathways explaining N-nitrosamine occurrences in sediment: NDBA and NDPhA were positively correlated with bulk water ammonia and pH levels, and NPYR with sediment content of organic carbon and iron. Interestingly, N-nitrosamine occurrences up- and downstream of WWTPs were statistically indistinguishable (p>0.05). This is the first report on the occurrence of the carcinogenic N-nitrosamines NDBA, NDPhA, and NPYR in U.S. freshwater sediments. Discovery of this phenomenon warrants further research on the compounds' origin, environmental persistence, aquatic toxicity, and risks posed.
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Affiliation(s)
- Adam J Gushgari
- Center for Environmental Security, The Biodesign Institute, Global Security Initiative, Arizona State University, 781 E. Terrace Mall, Tempe, AZ 85287, United States
| | - Rolf U Halden
- Center for Environmental Security, The Biodesign Institute, Global Security Initiative, Arizona State University, 781 E. Terrace Mall, Tempe, AZ 85287, United States.
| | - Arjun K Venkatesan
- Center for Environmental Security, The Biodesign Institute, Global Security Initiative, Arizona State University, 781 E. Terrace Mall, Tempe, AZ 85287, United States
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Kodamatani H, Iwaya Y, Saga M, Saito K, Fujioka T, Yamazaki S, Kanzaki R, Tomiyasu T. Ultra-sensitive HPLC-photochemical reaction-luminol chemiluminescence method for the measurement of secondary amines after nitrosation. Anal Chim Acta 2017; 952:50-58. [DOI: 10.1016/j.aca.2016.11.045] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 11/11/2016] [Accepted: 11/18/2016] [Indexed: 10/20/2022]
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Spahr S, Cirpka OA, von Gunten U, Hofstetter TB. Formation of N-Nitrosodimethylamine during Chloramination of Secondary and Tertiary Amines: Role of Molecular Oxygen and Radical Intermediates. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:280-290. [PMID: 27958701 DOI: 10.1021/acs.est.6b04780] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
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 18O-kinetic isotope effects (18O-KIE) for the reactions of aqueous O2, and studied the impact of radical scavengers on NDMA formation. Although the molar NDMA yields from five N,N-dimethylamine-containing precursors varied between 1.4% and 90%, we observed the stoichiometric removal of one O2 per N,N-dimethylamine group of the precursor indicating that the oxygenation of N atoms did not determine the molar NDMA yield. Small 18O-KIEs between 1.0026 ± 0.0003 and 1.0092 ± 0.0009 found for all precursors as well as completely inhibited NDMA formation in the presence of radical scavengers (ABTS and trolox) imply that O2 reacted with radical species. Our study suggests that aminyl radicals from the oxidation of organic amines by NH2Cl and N-peroxyl radicals from the reaction of aminyl radicals with aqueous O2 are part of the NDMA formation mechanism.
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Affiliation(s)
- Stephanie Spahr
- Eawag, Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf, Switzerland
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Federale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
| | - Olaf A Cirpka
- Center for Applied Geoscience, University of Tübingen , D-72074 Tübingen, Germany
| | - Urs von Gunten
- Eawag, Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf, Switzerland
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Federale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich , CH-8092 Zürich, Switzerland
| | - Thomas B Hofstetter
- Eawag, Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich , CH-8092 Zürich, Switzerland
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Lim S, Lee W, Na S, Shin J, Lee Y. N-nitrosodimethylamine (NDMA) formation during ozonation of N,N-dimethylhydrazine compounds: Reaction kinetics, mechanisms, and implications for NDMA formation control. WATER RESEARCH 2016; 105:119-128. [PMID: 27611639 DOI: 10.1016/j.watres.2016.08.054] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 08/22/2016] [Accepted: 08/26/2016] [Indexed: 05/17/2023]
Abstract
Compounds with N,N-dimethylhydrazine moieties ((CH3)2N-N-) form N-nitrosodimethylamine (NDMA) during ozonation, but the relevant reaction chemistry is hitherto poorly understood. This study investigated the reaction kinetics and mechanisms of NDMA formation during ozonation of unsymmetrical dimethylhydrazine (UDMH) and daminozide (DMZ) as structural model N,N-dimethylhydrazine compounds. The reaction of ozone with these NDMA precursor compounds was fast, and kO3 at pH 7 was 2 × 106 M-1 s-1 for UDMH and 5 × 105 M-1 s-1 for DMZ. Molar NDMA yields (i.e., Δ[NDMA]/Δ[precursor] × 100) were 84% and 100% for UDMH and DMZ, respectively, determined at molar ozone dose ratio ([O3]0/[precursor]0) of ≥4 in the presence of tert-butanol as hydroxyl radical (OH) scavenger. The molar NDMA yields decreased significantly in the absence of tert-butanol, indicating OH formation and its subsequent reaction with the parent precursors forming negligible NDMA. The kOH at pH 7 was 4.9 × 109 M-1 s-1 and 3.4 × 109 M-1 s-1 for UDMH and DMZ, respectively. Reaction mechanisms are proposed in which an ozone adduct is formed at the nitrogen next to N,N-dimethylamine which decomposes via homolytic and heterolytic cleavages of the -N+-O-O-O- bond, forming NDMA as a final product. The heterolytic cleavage pathway explains the significant OH formation via radical intermediates. Overall, significant NDMA formation was found to be unavoidable during ozonation or even O3/H2O2 treatment of waters containing N,N-dimethylhydrazine compounds due to their rapid reaction with ozone forming NDMA with high yield. Thus, source control or pre-treatment of N,N-dimethylhydrazine precursors and post-treatment of NDMA are proposed as the mitigation options.
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Affiliation(s)
- Sungeun Lim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 500-712, Republic of Korea
| | - Woongbae Lee
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 500-712, Republic of Korea
| | - Soyoung Na
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 500-712, Republic of Korea
| | - Jaedon Shin
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 500-712, Republic of Korea
| | - Yunho Lee
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 500-712, Republic of Korea.
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Kodamatani H, Yamasaki H, Sakaguchi T, Itoh S, Iwaya Y, Saga M, Saito K, Kanzaki R, Tomiyasu T. Rapid method for monitoring N -nitrosodimethylamine in drinking water at the ng/L level without pre-concentration using high-performance liquid chromatography-chemiluminescence detection. J Chromatogr A 2016; 1460:202-6. [DOI: 10.1016/j.chroma.2016.07.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/27/2016] [Accepted: 07/05/2016] [Indexed: 11/16/2022]
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24
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Sgroi M, Roccaro P, Oelker G, Snyder SA. N-nitrosodimethylamine (NDMA) formation during ozonation of wastewater and water treatment polymers. CHEMOSPHERE 2016; 144:1618-1623. [PMID: 26517390 DOI: 10.1016/j.chemosphere.2015.10.023] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Revised: 10/02/2015] [Accepted: 10/05/2015] [Indexed: 06/05/2023]
Abstract
N-Nitrosodimethylamine (NDMA) formation by ozonation was investigated in the effluents of four different wastewater treatment plants destined for alternative reuse. Very high levels of NDMA formation were observed in wastewaters from treatment plants non operating with biological nitrogen removal. Selected experiments showed that hydroxyl radical did not have a significant role in NDMA formation during ozonation of wastewater. Furthermore, ozonation of three different polymers used for water treatment, including polyDADMAC, anionic polyacrylamide, and cationic polyacrylamide, spiked in wastewater did not increase the NDMA formation. Effluent organic matter (EfOM) likely reduced the availability of ozone in water able to react with polymers and quenched the produced ·OH radicals which limited polymer degradation and subsequent NDMA production. Excellent correlations were observed between NDMA formation, UV absorbance at 254 nm, and total fluorescence reduction. These data provide evidence that UV and fluorescence surrogates could be used for monitoring and/or controlling NDMA formation during ozonation.
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Affiliation(s)
- Massimiliano Sgroi
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125 Catania, Italy; Department of Chemical & Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, AZ 85721, USA
| | - Paolo Roccaro
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125 Catania, Italy; Department of Chemical & Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, AZ 85721, USA
| | - Gregg Oelker
- United Water, Edward C. Little Water Reclamation Facility, 1935 South Hughes Way, El Segundo, CA 90245, USA
| | - Shane A Snyder
- Department of Chemical & Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, AZ 85721, USA; National University of Singapore, NUS Environmental Research Institute (NERI), 5A Engineering Drive 1, T-Lab Building, #02-01, Singapore 117411, Singapore.
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25
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Lv J, Wang L, Song Y, Li Y. N-Nitrosodimethylamine formation from ozonation of chlorpheniramine: Influencing factors and transformation mechanism. JOURNAL OF HAZARDOUS MATERIALS 2015; 299:584-94. [PMID: 26261866 DOI: 10.1016/j.jhazmat.2015.07.062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 07/21/2015] [Accepted: 07/23/2015] [Indexed: 05/17/2023]
Abstract
As a disinfection byproduct, the detection of N-nitrosodimethylamine (NDMA) in aquatic environments across the globe has caused widespread concern due to its potential carcinogenicity. In this study, the possibility of NDMA formation from chlorpheniramine ozonation was investigated. The influencing factors including the initial chlorpheniramine concentration, ozone dose, pH, and water matrix were quantified. Furthermore, the mechanisms for chlorpheniramine transformation and NDMA formation were explored. Our results demonstrate that ozonation is effective in removing chlorpheniramine. Generation of dimethylamine (DMA) and NDMA was observed during chlorpheniramine ozonation. Higher initial chlorpheniramine concentration and ozone dose resulted in higher production of NDMA. Acidic conditions (pH≤5) did not facilitate the production of NDMA. Ozone molecules played a dominant role in chlorpheniramine degradation, and influenced DMA release and NDMA formation. DMA and NDMA generations as well as their degradations were mainly attributed to hydroxyl radicals (·OH) produced by ozone decomposition. Water matrix properties such as HCO3(-) and humic acid affected DMA and NDMA generation due to ·OH competition. The degradation intermediates of chlorpheniramine were identified, among which only the intermediates with a DMA group were attributable to NDMA formation. A possible pathway for NDMA formation from chlorpheniramine ozonation is proposed.
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Affiliation(s)
- Juan Lv
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093, PR China
| | - Lin Wang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Yun Song
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Yongmei Li
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China.
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26
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Zeng T, Mitch WA. Contribution of N-Nitrosamines and Their Precursors to Domestic Sewage by Greywaters and Blackwaters. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:13158-67. [PMID: 26496512 DOI: 10.1021/acs.est.5b04254] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
N-nitrosamines and their precursors are significant concerns for water utilities exploiting wastewater-impacted water supplies, particularly those practicing potable reuse of wastewater. Previous efforts to identify specific precursors in municipal wastewater accounting for N-nitrosamine formation have met with limited success. As an alternative, we quantified the relative importance of greywater (i.e., shower, kitchen sink, bathroom washbasin, and laundry) and blackwater (i.e., urine and feces) streams in terms of their loadings of ambient specific and total N-nitrosamines and chloramine-reactive and ozone-reactive N-nitrosamine precursors to domestic sewage. Accounting for the volume fractions of individual greywater and blackwater streams, laundry water represented the most significant source of N-nitrosamines and their precursors, followed by shower water and urine. Laundry water was particularly important for ozone-reactive N-nitrosamine precursors, accounting for ∼99% of N-nitrosodimethylamine (NDMA) precursors and ∼69% of precursors for other uncharacterized N-nitrosamines. For the other greywater streams, consumer products contributed additional N-nitrosamines and precursors, but the remarkable uniformity across different products suggested the importance of common macroconstituents. The consumption of a standard dose of the antacid ranitidine substantially increased NDMA and its chloramine-reactive precursors in urine. Nevertheless, nearly 40% of the American population would need to consume ranitidine daily to match the NDMA loadings from laundry water.
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Affiliation(s)
- Teng Zeng
- Department of Civil and Environmental Engineering, Stanford University , 473 Via Ortega, Stanford, California 94305, United States
- National Science Foundation Engineering Research Center for Re-Inventing the Nation's Urban Water Infrastructure (ReNUWIt) , 473 Via Ortega, Stanford, California 94305, United States
| | - William A Mitch
- Department of Civil and Environmental Engineering, Stanford University , 473 Via Ortega, Stanford, California 94305, United States
- National Science Foundation Engineering Research Center for Re-Inventing the Nation's Urban Water Infrastructure (ReNUWIt) , 473 Via Ortega, Stanford, California 94305, United States
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27
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Gan W, Bond T, Yang X, Westerhoff P. Role of Chlorine Dioxide in N-Nitrosodimethylamine Formation from Oxidation of Model Amines. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:11429-11437. [PMID: 26335270 DOI: 10.1021/acs.est.5b01729] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
N-Nitrosodimethylamine (NDMA) is an emerging disinfection byproduct, and we show that use of chlorine dioxide (ClO2) has the potential to increase NDMA formation in waters containing precursors with hydrazine moieties. NDMA formation was measured after oxidation of 13 amines by monochloramine and ClO2 and pretreatment with ClO2 followed by postmonochloramination. Daminozide, a plant growth regulator, was found to yield 5.01 ± 0.96% NDMA upon reaction with ClO2, although no NDMA was recorded during chloramination. The reaction rate was estimated to be ∼0.0085 s(-1), and on the basis of our identification by mass spectrometry of the intermediates, the reaction likely proceeds via the hydrolytic release of unsymmetrical dimethylhydrazine (UDMH), with the hydrazine structure a key intermediate in NDMA formation. The presence of UDMH was confirmed by gas chromatography-mass spectrometry analysis. For 10 of the 13 compounds, ClO2 preoxidation reduced NDMA yields compared with monochloramination alone, which is explained by our measured release of dimethylamine. This work shows potential preoxidation strategies to control NDMA formation may not impact all organic precursors uniformly, so differences might be source specific depending upon the occurrence of different precursors in source waters. For example, daminozide is a plant regulator, so drinking water that is heavily influenced by upstream agricultural runoff could be at risk.
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Affiliation(s)
- Wenhui Gan
- SYSU-HKUST Research Center for Innovative Environmental Technology, School of Environmental Science and Engineering, Sun Yat-sen University , Guangzhou 510275, China
| | - Tom Bond
- Department of Civil and Environmental Engineering, Imperial College London , London SW7 2AZ, United Kingdom
| | - Xin Yang
- SYSU-HKUST Research Center for Innovative Environmental Technology, School of Environmental Science and Engineering, Sun Yat-sen University , Guangzhou 510275, China
| | - Paul Westerhoff
- School of Sustainable Engineering and the Built Environment, Arizona State University , Tempe, Arizona 85287-3005, United States
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28
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Gerrity D, Pisarenko AN, Marti E, Trenholm RA, Gerringer F, Reungoat J, Dickenson E. Nitrosamines in pilot-scale and full-scale wastewater treatment plants with ozonation. WATER RESEARCH 2015; 72:251-261. [PMID: 25037928 DOI: 10.1016/j.watres.2014.06.025] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 06/13/2014] [Accepted: 06/16/2014] [Indexed: 06/03/2023]
Abstract
Ozone-based treatment trains offer a sustainable option for potable reuse applications, but nitrosamine formation during ozonation poses a challenge for municipalities seeking to avoid reverse osmosis and high-dose ultraviolet (UV) irradiation. Six nitrosamines were monitored in full-scale and pilot-scale wastewater treatment trains. The primary focus was on eight treatment trains employing ozonation of secondary or tertiary wastewater effluents, but two treatment trains with chlorination or UV disinfection of tertiary wastewater effluent and another with full advanced treatment (i.e., reverse osmosis and advanced oxidation) were also included for comparison. N-nitrosodimethylamine (NDMA) and N-nitrosomorpholine (NMOR) were the most prevalent nitrosamines in untreated (up to 89 ng/L and 67 ng/L, respectively) and treated wastewater. N-nitrosomethylethylamine (NMEA) and N-nitrosodiethylamine (NDEA) were detected at one facility each, while N-nitrosodipropylamine (NDPrA) and N-nitrosodibutylamine (NDBA) were less than their method reporting limits (MRLs) in all samples. Ozone-induced NDMA formation ranging from <10 to 143 ng/L was observed at all but one site, but the reasons for the variation in formation remain unclear. Activated sludge, biological activated carbon (BAC), and UV photolysis were effective for NDMA mitigation. NMOR was also removed with activated sludge but did not form during ozonation.
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Affiliation(s)
- Daniel Gerrity
- Applied Research and Development Center, Southern Nevada Water Authority, River Mountain Water Treatment Facility, P.O. Box 99954, Las Vegas, NV 89193-9954, United States; Trussell Technologies, Inc., 380 Stevens Avenue, Suite 308, Solana Beach, CA 92075, United States; Department of Civil and Environmental Engineering and Construction, University of Nevada, Las Vegas, 4505 South Maryland Parkway, Box 454015, Las Vegas, NV 89154-4015, United States.
| | - Aleksey N Pisarenko
- Applied Research and Development Center, Southern Nevada Water Authority, River Mountain Water Treatment Facility, P.O. Box 99954, Las Vegas, NV 89193-9954, United States; Trussell Technologies, Inc., 380 Stevens Avenue, Suite 308, Solana Beach, CA 92075, United States
| | - Erica Marti
- Applied Research and Development Center, Southern Nevada Water Authority, River Mountain Water Treatment Facility, P.O. Box 99954, Las Vegas, NV 89193-9954, United States; Department of Civil and Environmental Engineering and Construction, University of Nevada, Las Vegas, 4505 South Maryland Parkway, Box 454015, Las Vegas, NV 89154-4015, United States
| | - Rebecca A Trenholm
- Applied Research and Development Center, Southern Nevada Water Authority, River Mountain Water Treatment Facility, P.O. Box 99954, Las Vegas, NV 89193-9954, United States
| | - Fred Gerringer
- Trussell Technologies, Inc., 380 Stevens Avenue, Suite 308, Solana Beach, CA 92075, United States
| | - Julien Reungoat
- Advanced Water Management Centre, University of Queensland, Level 4, Gehrmann Building (60), St. Lucia, QLD 4072, Australia
| | - Eric Dickenson
- Applied Research and Development Center, Southern Nevada Water Authority, River Mountain Water Treatment Facility, P.O. Box 99954, Las Vegas, NV 89193-9954, United States.
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Marti EJ, Pisarenko AN, Peller JR, Dickenson ERV. N-nitrosodimethylamine (NDMA) formation from the ozonation of model compounds. WATER RESEARCH 2015; 72:262-270. [PMID: 25241951 DOI: 10.1016/j.watres.2014.08.047] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 08/19/2014] [Accepted: 08/26/2014] [Indexed: 06/03/2023]
Abstract
Nitrosamines are a class of toxic disinfection byproducts commonly associated with chloramination, of which several were included on the most recent U.S. EPA Contaminant Candidate List. Nitrosamine formation may be a significant barrier to ozonation in water reuse applications, particularly for direct or indirect potable reuse, since recent studies show direct formation during ozonation of natural water and treated wastewaters. Only a few studies have identified precursors which react with ozone to form N-nitrosodimethylamine (NDMA). In this study, several precursor compound solutions, prepared in ultrapure water and treated wastewater, were subjected to a 10 M excess of ozone. In parallel experiments, the precursor solutions in ultrapure water were exposed to gamma radiation to determine NDMA formation as a byproduct of reactions of precursor compounds with hydroxyl radicals. The results show six new NDMA precursor compounds that have not been previously reported in the literature, including compounds with hydrazone and carbamate moieties. Molar yields in deionized water were 61-78% for 3 precursors, 12-23% for 5 precursors and <4% for 2 precursors. Bromide concentration was important for three compounds (1,1-dimethylhydrazine, acetone dimethylhydrazone and dimethylsulfamide), but did not enhance NDMA formation for the other precursors. NDMA formation due to chloramination was minimal compared to formation due to ozonation, suggesting distinct groups of precursor compounds for these two oxidants. Hydroxyl radical reactions with the precursors will produce NDMA, but formation is much greater in the presence of molecular ozone. Also, hydroxyl radical scavenging during ozonation leads to increased NDMA formation. Molar conversion yields were higher for several precursors in wastewater as compared to deionized water, which could be due to catalyzed reactions with constituents found in wastewater or hydroxyl radical scavenging.
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Affiliation(s)
- Erica J Marti
- Southern Nevada Water Authority, Applied Research & Development Center, PO Box 99954, Las Vegas, NV 89193, USA; University of Nevada, Las Vegas, Civil & Environmental Engineering and Construction, Las Vegas, NV, USA.
| | | | - Julie R Peller
- Indiana University Northwest, Chemistry Department, Gary, IN, USA.
| | - Eric R V Dickenson
- Southern Nevada Water Authority, Applied Research & Development Center, PO Box 99954, Las Vegas, NV 89193, USA.
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Selbes M, Kim D, Karanfil T. The effect of pre-oxidation on NDMA formation and the influence of pH. WATER RESEARCH 2014; 66:169-179. [PMID: 25203542 DOI: 10.1016/j.watres.2014.08.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Revised: 08/12/2014] [Accepted: 08/13/2014] [Indexed: 06/03/2023]
Abstract
N-nitrosodimethylamine (NDMA), a probable human carcinogen, is a disinfection by-product that has been detected in chloraminated drinking water systems. Pre-oxidation of the NDMA precursors prior to chloramination can be a viable approach for water utilities to control the NDMA levels. This study examined the effects of (i) commonly used oxidants (i.e., chlorine, chlorine dioxide and ozone) in water treatment, (ii) oxidant concentration and contact time (CT), and (iii) pre-oxidation pH on the formation of NDMA from subsequent chloramination. Fifteen model precursors with NDMA molar yields ranging from approximately 0.1%-90% were examined. Pre-chlorination reduced NDMA formation from most precursors by 10%-50% except quaternary amine polymers (i.e., PolyDADMAC, PolyACRYL, PolyAMINE). Pre-oxidation with chlorine dioxide and ozone achieved the same or higher deactivation of NDMA precursors (e.g., ranitidine) while increasing NDMA formation for some other precursors (e.g., daminozid). The increases with chlorine dioxide exposure were attributed to the release of oxidation products with dimethylamine (DMA) moiety, which may form more NDMA upon chloramination than the unoxidizied parent compound. On the other hand, chlorine dioxide was effective, if a precursors NDMA yield were higher than DMA. The ozone-triggered increases could be related to direct NDMA formation from DMA which are released by ozonation of amines with DMA moiety, amides or hydrazines. However, hydroxyl radicals formed from the decomposition of ozone would be also involved in decomposition of formed NDMA, reducing the overall NDMA levels at longer contact times. pH conditions influenced significantly the effectiveness of deactivation of precursors depending on the type of precursor and oxidant used.
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Affiliation(s)
- Meric Selbes
- Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625, USA
| | - Daekyun Kim
- Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625, USA
| | - Tanju Karanfil
- Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625, USA.
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31
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Kosaka K, Asami M, Ohkubo K, Iwamoto T, Tanaka Y, Koshino H, Echigo S, Akiba M. Identification of a new N-nitrosodimethylamine precursor in sewage containing industrial effluents. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:11243-11250. [PMID: 25184404 DOI: 10.1021/es502284t] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
N-Nitrosodimethylamine (NDMA), a potential human carcinogen, is known to be a disinfection byproduct of chloramination and ozonation. NDMA is formed during ozonation at water purification plants in the Yodo River basin, a major drinking water source in western Japan. An NDMA precursor, 1,1,5,5-tetramethylcarbohydrazide (TMCH) was identified in sewage containing industrial effluents via ultrahigh performance liquid chromatography-tandem mass spectrometry, and ultrahigh performance liquid chromatography-time-of-flight mass spectrometry, as well as nuclear magnetic resonance spectroscopy. The mean of the NDMA molar formation yield of TMCH upon ozonation in four water matrices was 140%. TMCH removal was low during biological treatment processes at a sewage treatment plant. The mean TMCH contribution to total NDMA precursors upon ozonation of the primary, secondary, and final effluents of the sewage treatment plant in January and February of 2014 was 43-72%, 51-72%, and 42-60%, respectively, while the contributions of 4,4'-hexamethylenebis(1,1-dimethylsemicarbazide) and 1,1,1',1'-tetramethyl-4,4'-(methylene-di-p-phenylene)disemicarbazide, two other known NDMA precursors, were limited to 0.6% and 6.9%, respectively. Thus, TMCH was identified as the primary precursor yielding NDMA upon ozonation in the Yodo River basin.
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Affiliation(s)
- Koji Kosaka
- Department of Environmental Health, National Institute of Public Health , 2-3-6 Minami, Wako, Saitama 351-0197, Japan
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32
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Sgroi M, Roccaro P, Oelker GL, Snyder SA. N-nitrosodimethylamine formation upon ozonation and identification of precursors source in a municipal wastewater treatment plant. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:10308-15. [PMID: 25029629 DOI: 10.1021/es5011658] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Ozone doses normalized to the dissolved organic carbon concentration were applied to the primary influent, primary effluent, and secondary effluent of a wastewater treatment plant producing water destined for potable reuse. Results showed the most N-Nitrosodimethylamine (NDMA) production from primary effluent, and the recycle streams entering the primary clarifiers were identified as the main source of NDMA precursors. The degradation of aminomethylated polyacrylamide (Mannich) polymer used for sludge treatment was a significant cause of precursor occurrence. A strong correlation between NDMA formation and ammonia concentration was found suggesting an important role of ammonia oxidation on NDMA production. During ozonation tests in DI water using dimethylamine (DMA) as model precursor, the NDMA yield significantly increased in the presence of ammonia and bromide due to the formation of hydroxylamine and brominated nitrogenous oxidants. In addition, NDMA formation during ozonation of dimethylformamide (DMF), the other model precursor used in this study, occurred only in the presence of ammonia, and it was attributable to the oxidation of DMF by hydroxyl radicals. Filtered wastewater samples (0.7 μm) produced more NDMA than unfiltered samples, suggesting that ozone reacted with dissolved precursors and supporting the hypothesis of polymer degradation. Particularly, the total suspended solids content similarly affected NDMA formation and the UV absorbance decrease during ozonation due to the different ozone demand created in filtered and unfiltered samples.
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Affiliation(s)
- Massimiliano Sgroi
- Department of Civil & Environmental Engineering, University of Catania , Viale A. Doria 6, 95125, Catania, Italy
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33
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Yoon S, Tanaka H. Optimum conditions for testing N-nitrosamine formation potential (FP) through ozonation in wastewater samples. J IND ENG CHEM 2014. [DOI: 10.1016/j.jiec.2013.11.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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34
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Zhang S, Yu G, Chen J, Wang B, Huang J, Deng S. Unveiling formation mechanism of carcinogenic N-nitrosodimethylamine in ozonation of dimethylamine: a density functional theoretical investigation. JOURNAL OF HAZARDOUS MATERIALS 2014; 279:330-5. [PMID: 25072138 DOI: 10.1016/j.jhazmat.2014.06.078] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 06/25/2014] [Accepted: 06/27/2014] [Indexed: 05/17/2023]
Abstract
Recent studies found that ozonation of organic pollutants with dimethylamino groups produces N-nitrosodimethylamine (NDMA) that is highly carcinogenic to humans. However, the formation mechanism of NDMA remains inexplicit, and previously proposed mechanisms are inconsistent with experimental observations. In this study, the formation mechanism of NDMA in ozonation was explored by density functional theory (DFT) calculations, with dimethylamine (DMA) as a model compound. By calculating Gibbs energies and energy barriers, formation of NDMA in ozonation of DMA was observed to proceed through a hydroxylamine mechanism. The calculation results show that hydroxylamine is generated through DMA reacting with hydroxyl radicals (HO•) formed from hydrolysis of ozone. DMA reacting with hydroxylamine can produce unsymmetrical dimethylhydrazine (UDMH), a well-known NDMA precursor. Transformation of UDMH to NDMA is mainly induced by ozone or HO• rather than dissolved oxygen proposed previously. The reaction of DMA and hydroxylamine is pH dependent, with energy barriers increasing from neutral pH to the second pKa of hydroxylamine and then decreasing. This is in accordance with the experimentally observed pH dependence of NDMA yield in ozonation, indicating that the hydroxylamine mechanism is responsible for the NDMA formation in ozonation.
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Affiliation(s)
- Siyu Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, POPs Research Center, Tsinghua University, Beijing 100084, China; Veolia Environment Joint Research Center for Advanced Technology, Tsinghua University, Beijing 100084, China
| | - Gang Yu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, POPs Research Center, Tsinghua University, Beijing 100084, China; Veolia Environment Joint Research Center for Advanced Technology, Tsinghua University, Beijing 100084, China.
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Bin Wang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, POPs Research Center, Tsinghua University, Beijing 100084, China; Veolia Environment Joint Research Center for Advanced Technology, Tsinghua University, Beijing 100084, China
| | - Jun Huang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, POPs Research Center, Tsinghua University, Beijing 100084, China; Veolia Environment Joint Research Center for Advanced Technology, Tsinghua University, Beijing 100084, China
| | - Shubo Deng
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, POPs Research Center, Tsinghua University, Beijing 100084, China; Veolia Environment Joint Research Center for Advanced Technology, Tsinghua University, Beijing 100084, China
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35
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Yoon S, Tanaka H. Formation of N-nitrosamines by chloramination or ozonation of amines listed in Pollutant Release and Transfer Registers (PRTRs). CHEMOSPHERE 2014; 95:88-95. [PMID: 24011895 DOI: 10.1016/j.chemosphere.2013.07.090] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 07/30/2013] [Accepted: 07/31/2013] [Indexed: 05/17/2023]
Abstract
We determined whether or not the chloramination or ozonation of amines and hydrazines listed in Pollutant Release and Transfer Registers (PRTRs) results in the formation of N-nitrosamines when reacted in secondary wastewater effluent. We selected 12 primary, 2 secondary, 2 tertiary amines and 3 hydrazines from the PRTRs of Japan, the USA, and Korea. In this study, based on the assumption that there is a production of N-nitrosamines by not only the original selected amines and hydrazines but also the intermediate products in case of chloramination and ozonation, it was examined whether precursors were identified by selected amines and hydrazines based on the gap of the N-nitrosamines formation potential between day 0 and day 10 rather than analyzing the contribution depending on the concentration of selected amines and hydrazines. Many of the primary amines (notably 2,6-xylidine) and all of the secondary and tertiary amines produced N-nitrosodimethylamine (NDMA) by chloramination. Furthermore, the primary amines 2,6-xylidine, 3,3'-dimethylbenzidine, 4,4'-methylenebis(2-chloroaniline), 4-aminoazobenzene, p-chloroaniline, and p-cresidine produced more NDMA than did the secondary amines. The secondary amines produced mainly NDMA. Ozonation produced NDMA only from the hydrazine 1,1-dimethylhydrazine, and at a higher concentration than by chloramination. We identified 2,6-xylidine, 3,3'-dimethylbenzidine, 4,4'-methylenebis(2-chloroaniline), 4-aminoazobenzene, p-chloroaniline, p-cresidine, 1,1-dimethylhydrazine, diethylamine, 4,4'-methylenebis(N,N-dimethyl)benzenamine, and chinomethionat as warranting further study.
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Affiliation(s)
- Suchul Yoon
- Research Center for Environmental Quality Management, Kyoto University, 1-2 Yumihama, Otsu, Shiga 520-0811, Japan.
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36
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Shen R, Andrews SA. NDMA formation from amine-based pharmaceuticals--impact from prechlorination and water matrix. WATER RESEARCH 2013; 47:2446-2457. [PMID: 23453587 DOI: 10.1016/j.watres.2013.02.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 02/06/2013] [Accepted: 02/08/2013] [Indexed: 06/01/2023]
Abstract
The presence of N-nitrosodimethylamine (NDMA) in drinking water is most commonly associated with the chloramination of amine-based precursors. One option to control the NDMA formation is to remove the precursors via pre-oxidation, and prechlorination is among the most effective options in reducing NDMA formation. However, most of the findings to-date are based on single-precursor scenarios using the model precursor dimethylamine (DMA) and natural organic matter (NOM), while few studies have considered the potential interactions between water matrix components and the target precursors when investigating the prechlorination impact. Specifically, little is known for the behaviour of amine-based pharmaceuticals which have recently been reported to contribute to NDMA formation upon chloramination. This work demonstrates that prechlorination can affect both the ultimate NDMA conversion and the reaction kinetics from selected pharmaceuticals, and the nature and extent of the impact was compound-specific and matrix-specific. In the absence of NOM, the NDMA formation from most pharmaceuticals was reduced upon prechlorination, except for sumatriptan which showed a consistent increase in NDMA formation with increasing free chlorine contact time. In the presence of NOM, prechlorination was shown to enhance initial reactions by reducing the binding between NOM and pharmaceuticals, but prolonged prechlorination broke down NOM into smaller products which could then form new bonds with pharmaceuticals and thus inhibit their further conversion into NDMA.
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Affiliation(s)
- Ruqiao Shen
- Department of Civil Engineering, University of Toronto, 35 St. George St., Toronto, Ontario, Canada M5S 1A4.
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37
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Soltermann F, Lee M, Canonica S, von Gunten U. Enhanced N-nitrosamine formation in pool water by UV irradiation of chlorinated secondary amines in the presence of monochloramine. WATER RESEARCH 2013; 47:79-90. [PMID: 23098367 DOI: 10.1016/j.watres.2012.09.034] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 09/13/2012] [Accepted: 09/17/2012] [Indexed: 06/01/2023]
Abstract
N-Nitrosamines, in particular N-nitrosodimethylamine (NDMA), are carcinogens, which occur as chlorine disinfection by-products (DBPs) in swimming pools and hot tubs. UV treatment is a commonly used technique in swimming pools for disinfection and DBP attenuation. UV irradiation is known to efficiently degrade N-nitrosamines. However, UV irradiation (at λ = 254 nm) of chlorinated dimethylamine (CDMA) and monochloramine, two NDMA precursors present in swimming pool water, resulted in a substantial UV-induced NDMA formation (~1-2% molar yield based on initial CDMA concentration) simultaneously to NDMA photolysis. Maximum NDMA concentrations were found at UV doses in the range used for advanced oxidation (350-850 mJ cm(-2)). Very similar behaviour was found for other chlorinated secondary amines, namely diethylamine and morpholine. Effectiveness of UV irradiation for N-nitrosamine abatement depends on initial N-nitrosamine and precursor concentrations and the applied UV dose. N-Nitrosamine formation is hypothesized to occur via the reaction of nitric oxide or peroxynitrite with the secondary aminyl radical, which are products from the photolysis of monochloramine and chlorinated secondary amines, respectively. Experiments with pool water showed that similar trends were observed under pool water conditions. UV treatment (UV dose: ~360 mJ cm(-2)) slightly increased NDMA concentration in pool water instead of the anticipated 50% abatement in the absence of NDMA precursors.
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Affiliation(s)
- Fabian Soltermann
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
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38
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Shah AD, Krasner SW, Lee CFT, von Gunten U, Mitch WA. Trade-offs in disinfection byproduct formation associated with precursor preoxidation for control of N-nitrosodimethylamine formation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:4809-4818. [PMID: 22463122 DOI: 10.1021/es204717j] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Chloramines in drinking water may form N-nitrosodimethylamine (NDMA). Various primary disinfectants can deactivate NDMA precursors prior to chloramination. However, they promote the formation of other byproducts. This study compared the reduction in NDMA formation due to chlorine, ozone, chlorine dioxide, and UV over oxidant exposures relevant to Giardia control coupled with postchloramination under conditions relevant to drinking water practice. Ten waters impacted by treated wastewater, poly(diallyldimethylammonium chloride) (polyDADMAC) polymer, or anion exchange resin were examined. Ozone reduced NDMA formation by 50% at exposures as low as 0.4 mg×min/L. A similar reduction in NDMA formation by chlorination required ∼60 mg×min/L exposure. However, for some waters, chlorination actually increased NDMA formation at lower exposures. Chlorine dioxide typically had limited efficacy regarding NDMA precursor destruction; moreover, it increased NDMA formation in some cases. UV decreased NDMA formation by ∼30% at fluences >500 mJ/cm(2), levels relevant to advanced oxidation. For the selected pretreatment oxidant exposures, concentrations of regulated trihalomethanes, haloacetic acids, bromate, and chlorite typically remained below current regulatory levels. Chloropicrin and trichloroacetaldehyde formation were increased by preozonation or medium pressure UV followed by postchloramination. Among preoxidants, ozone achieved the greatest reduction in NDMA formation at the lowest oxidant exposure associated with each disinfectant. Accordingly, preozonation may inhibit NDMA formation with minimal risk of promotion of other byproducts. Bromide >500 μg/L generally increased NDMA formation during chloramination. Higher temperatures increased NDMA precursor destruction by preoxidants but also increased NDMA formation during postchloramination. The net effect of these opposing trends on NDMA formation was water-specific.
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Affiliation(s)
- Amisha D Shah
- Department of Chemical and Environmental Engineering, Yale University, Mason Lab 313b, 9 Hillhouse Avenue, New Haven, Connecticut 06520, USA
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39
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Ma F, Wan Y, Yuan G, Meng L, Dong Z, Hu J. Occurrence and source of nitrosamines and secondary amines in groundwater and its adjacent Jialu River basin, China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:3236-3243. [PMID: 22352424 DOI: 10.1021/es204520b] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The presence of mutagenic and carcinogenic nitrosamines in groundwater is of great concern. In this study, eight nitrosamines including N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosomethylethylamine (NMEA), N-nitrosopyrrolidine (NPYR), N-nitrosomorpholine (NMOR), N-nitrosopiperidine (NPIP), N-nitrosodi-n-propylamine (NDPA), and N-nitrosodi-n-butylamine (NDBA) and corresponding secondary amines were investigated in shallow groundwater, river water, and wastewater samples collected from the Jialu River basin. The total concentrations of nitrosamines and secondary amines in groundwater were ND-101.1 ng/L and 0.36-4.38 μg/L, respectively. NDMA and its secondary amine DMA (44.7%/40.1%) were the predominant compounds in groundwater, followed by NDEA/DEA (21.7%/29.3%) and NDBA/DBA (26.4%/27.4%). Relatively high concentrations of these six compounds were also observed in river water that was influenced by the direct discharge of industrial and domestic wastewater. Using acesulfame as a quantitative population marker, the contribution of domestic sources to the concentrations of nitrosamines and secondary amines was 39-85% in downstream reaches of the Jialu River, and that of industrial sources was estimated to be 65-98% in other sites of the area. Both on-site leakage of domestic and industrial wastewater and leaching from river water would contribute to the occurrence of target pollutants in groundwater. The target pollutants posed a cancer risk of 4.12 × 10(-5) to the local populations due to the direct usage of groundwater as potable water.
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Affiliation(s)
- Fujun Ma
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
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40
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Fischer K, Fries E, Körner W, Schmalz C, Zwiener C. New developments in the trace analysis of organic water pollutants. Appl Microbiol Biotechnol 2012; 94:11-28. [DOI: 10.1007/s00253-012-3929-z] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 01/26/2012] [Accepted: 01/28/2012] [Indexed: 10/28/2022]
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41
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Wang W, Ren S, Zhang H, Yu J, An W, Hu J, Yang M. Occurrence of nine nitrosamines and secondary amines in source water and drinking water: Potential of secondary amines as nitrosamine precursors. WATER RESEARCH 2011; 45:4930-4938. [PMID: 21843899 DOI: 10.1016/j.watres.2011.06.041] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 06/03/2011] [Accepted: 06/29/2011] [Indexed: 05/31/2023]
Abstract
Due to their high carcinogenicity, the control of nitrosamines, a group of disinfection by-products (DBPs), is an important issue for drinking water supplies. In this study, a method using ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry was improved for simultaneously analyzing nine nitrosamines in source water and finished water samples of twelve drinking water treatment plants (DWTPs) in China. The method detection limits of the nine target analytes were 0.2-0.9 ng/L for the source water samples and 0.1-0.7 ng/L for the finished water samples. Of the nine nitrosamines, six (N-nitrosodimethylamine (NDMA), nitrosodiethylamine (NDEA), N-nitrosomorpholine (NMor), N-nitrosodi-n-butylamine (NDBA), N-nitrosomethylethylamine (NMEA), and N-nitrosodiphenylamine (NDPhA)) were detected. The total nitrosamine concentrations in source water and finished water samples were no detection-42.4 ng/L and no detection-26.3 ng/L, respectively, and NDMA (no detection-13.9 ng/L and no detection-20.5 ng/L, respectively) and NDEA (no detection-16.3 ng/L and no detection-14.0 ng/L, respectively) were the most abundant. Meanwhile, the occurrence of nine secondary amines corresponding to the nine nitrosamines was also investigated. All of them except for di-n-propylamine were detected in some source water and finished water samples, and dimethylamine (no detection-3.9 μg/L and no detection-4.0 μg/L, respectively) and diethylamine (no detection-2.4 μg/L and no detection-1.8 μg/L, respectively) were the most abundant ones. Controlled experiments involving chloramination of four secondary amines confirmed that dimethylamine, diethylamine, morpholine and di-n-butylamine in water can form the corresponding nitrosamines, with diethylamine and morpholine showing significantly higher yields than dimethylamine which has already been identified as a precursor of NDMA. This study proved that diethylamine, morpholine and di-n-butylamine detected in raw water would be one of the important the precursors of NDEA, NMOR and NDBA, respectively, in drinking water.
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Affiliation(s)
- Wanfeng Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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42
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Nawrocki J, Andrzejewski P. Nitrosamines and water. JOURNAL OF HAZARDOUS MATERIALS 2011; 189:1-18. [PMID: 21353742 DOI: 10.1016/j.jhazmat.2011.02.005] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 01/17/2011] [Accepted: 02/03/2011] [Indexed: 05/30/2023]
Abstract
This paper provides an overview of all current issues that are connected to the presence of nitrosamines in water technology. N-nitrosodimethylamine (NDMA) is the most frequently detected member of this family. Nitrosamines became the hottest topic in drinking water science when they were identified as disinfection by-products (DBPs) in chloraminated waters. The danger that they pose to consumer health seems to be much higher than that from chlorinated DBPs. This review summarizes our contemporary knowledge of these compounds in water, their occurrence, and precursors of nitrosamines in drinking and wastewaters, in addition to attempts to remove nitrosamines from water. The paper also reviews our knowledge of the mechanisms of nitrosamine formation in water technology. The current, commonly accepted mechanism of NDMA formation during chloramination of drinking waters assumes that dichloramine reacts with dimethylamine, forms unsymmetrical dimethylhydrazine and further oxidizes to NDMA. The question to answer is which precursors are responsible for delivering the DMA moiety for the reaction since the presence of DMA in water cannot explain the quantities of NDMA that are formed. There are also reports that other oxidants that are commonly used in water technology may generate NDMA. However, the mechanisms of such transformations are unknown. Methods for the removal of nitrosamines from water are described briefly. However, the research that has been undertaken on such methods seems to be at an early stage of development. It is predicted that photolytic methods may have the greatest potential for technological application.
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Affiliation(s)
- Jacek Nawrocki
- Laboratory of Water Treatment Technology, Faculty of Chemistry, A Mickiewicz University, Poznań, Poland.
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43
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Huy NV, Murakami M, Sakai H, Oguma K, Kosaka K, Asami M, Takizawa S. Occurrence and formation potential of N-nitrosodimethylamine in ground water and river water in Tokyo. WATER RESEARCH 2011; 45:3369-3377. [PMID: 21514620 DOI: 10.1016/j.watres.2011.03.053] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Revised: 01/28/2011] [Accepted: 03/27/2011] [Indexed: 05/30/2023]
Abstract
N-nitrosodimethylamine (NDMA), a disinfection byproduct of water and wastewater treatment processes, is a potent carcinogen. We investigated its occurrence and the potential for its formation by chlorination (NDMA-FP Cl2) and by chloramination (NDMA-FP NH2Cl) in ground water and river water in Tokyo. To characterize NDMA precursors, we revealed their molecular weight distributions in ground water and river water. We collected 23 ground water and 18 river water samples and analyzed NDMA by liquid chromatography-tandem mass spectrometry. NDMA-FP Cl2 was evaluated by chlorinating water samples with free chlorine for 24 h at pH 7.0 while residual free chlorine was kept at 1.0-2.0 mg Cl(2)/L. NDMA-FP NH2Cl was evaluated by dosing water samples with monochloramine at 140 mg Cl(2)/L for 10 days at pH 6.8. NDMA precursors and dissolved organic carbon (DOC) were fractionated by filtration through 30-, 3-, and 0.5 kDa membranes. NDMA concentrations were <0.5-5.2 ng/L (median: 0.9 ng/L) in ground water and <0.5-3.4 ng/L (2.2 ng/L) in river water. NDMA concentrations in ground water were slightly lower than or comparable to those in river water. Concentrations of NDMA-FP Cl2 were not much higher than concentrations of NDMA except in samples containing high concentrations of NH(3) and NDMA precursors. The increased NDMA was possibly caused by reactions between NDMA precursors and monochloramine unintentionally formed by the reaction between free chlorine and NH(3) in the samples. NDMA precursors ranged from 4 to 84 ng-NDMA eq./L in ground water and from 11 to 185 ng-NDMA eq./L in river water. Those in ground water were significantly lower than those in river water, suggesting that NDMA precursors were biodegraded, adsorbed, or volatilized during infiltration. The molecular weight of NDMA precursors in river water was dominant in the <0.5 kDa fraction, followed by 0.5-3 kDa. However, their distribution was inconsistent in ground water: one was dominant in the <0.5 kDa fraction, and the other in 0.5-3 kDa. Molecular weight distributions of NDMA precursors were very different from those of DOC. This is the first study to reveal the widespread occurrence and characterization of NDMA precursors in ground water.
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Affiliation(s)
- Nguyen Van Huy
- Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
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von Gunten U, Salhi E, Schmidt CK, Arnold WA. Kinetics and mechanisms of N-nitrosodimethylamine formation upon ozonation of N,N-dimethylsulfamide-containing waters: bromide catalysis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:5762-5768. [PMID: 20614903 DOI: 10.1021/es1011862] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
N,N-Dimethylsulfamide (DMS), a newly identified, ubiquitous degradation product of the fungicide tolylfluanide, has been shown to be a N-nitrosodimethylamine (NDMA) precursor during ozonation. In this study, batch ozonation experiments in ultrapure buffered water, surface water, and tap water were performed to determine the kinetics and elucidate the mechanism of NDMA formation from DMS. It was found that at circumneutral pH, DMS reacts slowly with ozone (k approximately 20 M(-1) s(-1)) and moderately with hydroxyl radicals (k=1.5x10(9) M(-1)s(-1)). The reaction of DMS with these oxidants does not lead to NDMA. NDMA was only formed if bromide was present during ozonation of DMS-containing waters. Bromide is oxidized to hypobromous acid (HOBr) by ozone which then reacts with the primary amine of DMS to form a Br-DMS species. The rate limiting step of the formation of Br-DMS is the formation of HOBr. The reaction to form Br-DMS has an apparent second order rate constant at pH 8 of >3x10(4) M(-1)s(-1). The Br-DMS is transformed by ozone to NDMA and nitrate (k>or=5000 M(-1) s(-1)), with yields of 54% and 39%, respectively, based on the primary amine nitrogen of DMS. These reactions release bromide, making bromide a catalyst. NDMA is also formed during ozonation of DMS in the presence of hypochlorous acid (20-30% yield). The last step of NDMA formation is an intramolecular rearrangement with sulfur dioxide extrusion. On the basis of the mechanistic and kinetic information, it was possible to model NDMA formation in DMS-containing Lake Zurich water.
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Affiliation(s)
- Urs von Gunten
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, 8600, Dubendorf, Switzerland.
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45
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Hollender J, Zimmermann SG, Koepke S, Krauss M, McArdell CS, Ort C, Singer H, von Gunten U, Siegrist H. Elimination of organic micropollutants in a municipal wastewater treatment plant upgraded with a full-scale post-ozonation followed by sand filtration. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:7862-9. [PMID: 19921906 DOI: 10.1021/es9014629] [Citation(s) in RCA: 475] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The removal efficiency for 220 micropollutants was studied at the scale of a municipal wastewater treatment plant (WWTP) upgraded with post-ozonation followed by sand filtration. During post-ozonation, compounds with activated aromatic moieties, amine functions, or double bonds such as sulfamethoxazole, diclofenac, or carbamazepine with second-order rate constants for the reaction with ozone >10(4) M(-1) s(-1) at pH 7 (fast-reacting) were eliminated to concentrations below the detection limit for an ozone dose of 0.47 g O3 g(-1) dissolved organic carbon (DOC). Compounds more resistant to oxidation by ozone such as atenolol and benzotriazole were increasingly eliminated with increasing ozone doses, resulting in >85% removal for a medium ozone dose (approximately 0.6 g O3 g(-1) DOC). Only a few micropollutants such as some X-ray contrast media and triazine herbicides with second-order rate constants <10(2) M(-1) s(-1) (slowly reacting) persisted to a large extent. With a medium ozone dose, only 11 micropollutants of 55 detected in the secondary effluent were found at >100 ng L(-1). The combination of reaction kinetics and reactor hydraulics, based on laboratory-and full-scale data, enabled a quantification of the results by model calculations. This conceptual approach allows a direct upscaling from laboratory- to full-scale systems and can be applied to other similar systems. The carcinogenic by-products N-nitrosodimethylamine (NDMA) (< or =14 ng L(-1)) and bromate (<10 microg L(-1)) were produced during ozonation, however their concentrations were below or in the range of the drinking water standards. Furthermore, it could be demonstrated that biological sand filtration is an efficient additional barrier for the elimination of biodegradable compounds formed during ozonation such as NDMA. The energy requirement for the additional post-ozonation step is about 0.035 kWh m(-3), which corresponds to 12% of a typical medium-sized nutrient removal plant (5 g DOC m(-3)).
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Affiliation(s)
- Juliane Hollender
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.
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46
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Kosaka K, Asami M, Konno Y, Oya M, Kunikane S. Identification of antiyellowing agents as precursors of N-nitrosodimethylamine production on ozonation from sewage treatment plant influent. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:5236-5241. [PMID: 19708347 DOI: 10.1021/es900227g] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In Japan, N-nitrosodimethylamine (NDMA) formation associated with ozonation at a relatively high concentration has been reported only at a small number of water treatment plants (WTPs) in the western part of Japan for which the source water is the Yodo River. In the present study, the formation of relatively high concentrations of NDMA was found upon ozonation of water samples taken from sewage treatment plants (STPs) located upstream of the water intake points of the WTPs in the Yodo River basin. NDMA concentrations before and after ozonation were 16-290 and 14-280 ng/L, respectively. At least some of the STPs investigated receive industrial effluents. At one STP in this area, an extremely high concentration of NDMA (10,000ng/L) was found in one influent water sample after ozonation. To identify potential NDMA precursors upon ozonation in the influent at this STP, the concentrated extracts of the influent were fractionated by high-performance liquid chromatography (HPLC). Ultraperformance liquid chromatography coupled with tandem mass spectrometry (UPLC/MS/MS) identified 4,4'-hexamethylenebis(1,1-dimethylsemicarbazide) (HDMS) and 1,1,1',1'-tetramethyl-4,4'-(methylene-di-p-phenylene)disemicarbazide (TMDS) as precursors of NDMA on ozonation of the influent. Both HDMS and TMDS are used as antiyellowing agents in polyurethane fibers and as light stabilizers in polyamide resins. Their contributions to NDMA production on ozonation of water samples at STPs were up to 17%. The remaining unidentified NDMA precursors may be hydrophilic compounds that were not trapped by the cartridges used for extraction of the water samples. HDMS and TMDS were frequently present in surface waters and STP effluents in the Yodo River basin and were also detected in surface waters from several other areas in Japan.
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Affiliation(s)
- Koji Kosaka
- Department of Water Supply Engineering, National Institute of Public Health, 2-3-6 minami, Wako, Saitama 351-0197, Japan.
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