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Luo Y, Liu C, He S, Liu J, Ren Y. Release regularity and cleaning measures of magnetic anion exchange resin during application. Chemosphere 2023; 323:138285. [PMID: 36868424 DOI: 10.1016/j.chemosphere.2023.138285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 02/07/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
Anion exchange resin is responsible for removing harmful anionic contaminants in drinking water treatment, but it may become a significant source of precursors for disinfection byproducts (DBPs) by shedding material during application without proper pretreatment. Batch contact experiments were performed to investigate the dissolution of magnetic anion exchange resins and their contribution to organics and DBPs. Dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) released from the resin were highly correlated with the dissolution conditions (contact time and pH), in which 0.7 mg/L DOC and 0.18 mg/L DON were distributed at exposure time of 2 h and pH 7. The formation potential of four DBPs in the shedding fraction was also revealed that trichloromethane (TCM), dichloroacetonitrile (DCAN), nitrosodimethylamine (NDMA), and dichloroacetamide (DCAcAm) concentrations could reach 21.4, 5.1, 12.1 μg/L, and 69.6 ng/L, respectively. Furthermore, the hydrophobic DOC that preferred to detach from the resin mainly originated from the residues of crosslinkers (divinylbenzene) and porogenic agents (straight-chain alkanes) detected by LC-OCD and GC-MS. Nevertheless, pre-cleaning inhibited the leaching of the resin, among which acid-base and ethanol treatments significantly lowered the concentration of leached organics, and formation potential of DBPs (TCM, DCAN, and DCAcAm) below 5 μg/L and NDMA dropped to 10 ng/L.
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Affiliation(s)
- Yuye Luo
- College of Environment, Hohai University, Nanjing, 210098, China
| | - Cheng Liu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China.
| | - Siyuan He
- College of Environment, Hohai University, Nanjing, 210098, China
| | - Jiaqi Liu
- College of Environment, Hohai University, Nanjing, 210098, China
| | - Yuanyuan Ren
- College of Environment, Hohai University, Nanjing, 210098, China
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2
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Kumar M, Shekhar S, Kumar R, Kumar P, Govarthanan M, Chaminda T. Drinking water treatment and associated toxic byproducts: Concurrence and urgence. Environ Pollut 2023; 320:121009. [PMID: 36634860 DOI: 10.1016/j.envpol.2023.121009] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 12/30/2022] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
Reclaimed water is highly required for environmental sustainability and to meet sustainable development goals (SDGs). Chemical processes are frequently associated with highly hazardous and toxic by-products, like nitrosamines, trihalomethanes, haloaldehydes, haloketones, and haloacetic acids. In this context, we aim to summarize the formation of various commonly produced disinfection by-products (DBPs) during wastewater treatment and their treatment approaches. Owing to DBPs formation, we discussed permissible limits, concentrations in various water systems reported globally, and their consequences on humans. While most reviews focus on DBPs detection methods, this review discusses factors affecting DBPs formation and critically reviews various remediation approaches, such as adsorption, reverse osmosis, nano/micro-filtration, UV treatment, ozonation, and advanced oxidation process. However, research in the detection of hazardous DBPs and their removal is quite at an early and initial stage, and therefore, numerous advancements are required prior to scale-up at commercial level. DBPs abatement in wastewater treatment approach should be considered. This review provides the baseline for optimizing DBPs formation and advancements in the remediation process, efficiently reducing their production and providing safe, clean drinking water. Future studies should focus on a more efficient and rigorous understanding of DBPs properties and degradation of hazardous pollutants using low-cost techniques in wastewater treatment.
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Affiliation(s)
- Manish Kumar
- Sustainability Cluster, University of Petroleum & Energy Studies, Dehradun, Uttarakhand, 248007, India; Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Campus Monterey, Monterrey, 64849, Nuevo Leon, Mexico.
| | - Shashank Shekhar
- Sustainability Cluster, University of Petroleum & Energy Studies, Dehradun, Uttarakhand, 248007, India
| | - Rakesh Kumar
- School of Ecology and Environment Studies, Nalanda University, Rajgir, 803116, Bihar, India
| | - Pawan Kumar
- Sustainability Cluster, University of Petroleum & Energy Studies, Dehradun, Uttarakhand, 248007, India
| | - Muthusamy Govarthanan
- Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, 41566, South Korea; Department of Biomaterials, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai, 600 077, India
| | - Tushara Chaminda
- Department of Civil and Environmental Engineering, Faculty of Engineering, University of Ruhuna, Galle, Sri Lanka
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3
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Luo Q, Miao Y, Liu C, Bei E, Zhang JF, Zhang LH, Deng YL, Qiu Y, Lu WQ, Wright JM, Chen C, Zeng Q. Maternal exposure to nitrosamines in drinking water during pregnancy and birth outcomes in a Chinese cohort. Chemosphere 2023; 315:137776. [PMID: 36623593 DOI: 10.1016/j.chemosphere.2023.137776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
Maternal exposure to regulated disinfection by-products (DBPs) during pregnancy has been linked with adverse birth outcomes. However, no human studies have focused on drinking water nitrosamines, a group of emerging unregulated nitrogenous DBPs that exhibits genotoxicity and developmental toxicity in experimental studies. This cohort study included 2457 mother-infant pairs from a single drinking water supply system in central China, and maternal trimester-specific and entire pregnancy exposure of drinking water nitrosamines were evaluated. Multivariable linear and Poisson regression models were used to estimate the associations between maternal exposure to nitrosamines in drinking water and birth outcomes [birth weight (BW), low birth weight (LBW), small for gestational age (SGA) and preterm delivery (PTD)]. Elevated maternal N-nitrosodimethylamine (NDMA) exposure in the second trimester and N-nitrosopiperidine (NPIP) exposure during the entire pregnancy were associated with decreased BW (e.g., β = -88.6 g; 95% CI: -151.0, -26.1 for the highest vs. lowest tertile of NDMA; p for trend = 0.01) and increased risks of PTD [e.g., risk ratio (RR) = 2.16; 95% CI: 1.23, 3.79 for the highest vs. lowest tertile of NDMA; p for trend = 0.002]. Elevated maternal exposure of N-nitrosodiethylamine (NDEA) in the second trimester was associated with increased risk of SGA (RR = 1.80; 95% CI: 1.09, 2.98 for the highest vs. lowest tertile; p for trend = 0.01). Our study detected associations of maternal exposure to drinking water nitrosamines during pregnancy with decreased BW and increased risks of SGA and PTD. These findings are novel but require replication in other study populations.
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Affiliation(s)
- Qiong Luo
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental Health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Yu Miao
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental Health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Chong Liu
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental Health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Er Bei
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, PR China
| | - Jin-Feng Zhang
- Maternal and Child Health Care Service Centre of Xiaonan District, Xiaogan City, Hubei, PR China
| | - Ling-Hua Zhang
- Maternal and Child Health Care Service Centre of Xiaonan District, Xiaogan City, Hubei, PR China
| | - Yan-Ling Deng
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental Health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Yu Qiu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, PR China
| | - Wen-Qing Lu
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental Health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - J Michael Wright
- Office of Research and Development, U.S. Environmental Protection Agency, Center for Public Health and Environmental Assessment, Cincinnati, OH, USA
| | - Chao Chen
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, PR China.
| | - Qiang Zeng
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental Health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China.
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4
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Norling MD, Clayer F, Gundersen CB. Levels of nitramines and nitrosamines in lake drinking water close to a CO 2 capture plant: A modelling perspective. Environ Res 2022; 212:113581. [PMID: 35654158 DOI: 10.1016/j.envres.2022.113581] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 05/16/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
While CO2 capture is considered a key climate change mitigation option, we must ensure that global implementation occurs without causing harm to the local environment and the human health. The most mature option for capture is using amines, which however, is associated with a risk of contaminating nearby drinking water sources with carcinogenic nitramines (NAs) and nitrosamines (NSAs). Here we present the first process-based simulation of NAs and NSAs in a catchment-lake system with the input of previously modelled atmospheric deposition rates. Considering full-scale CO2 capture at the Oslo waste incineration plant in Norway, future (∼10 y) levels in a nearby lake approach the national drinking water limit. We further quantified the effect of hydrological and biogeochemical processes and identified those with the highest sensitivity (NA biodegradation). The uncertainty of the results is presented by a probabilistic distribution (Monte Carlo analysis), incorporating variability in catchment, lake, and literature NA and NSA parameter values. This modelling tool allows for the site-specific assessment of the abovementioned risks related to amine-based CO2 capture and aspires to contribute to the sound evaluation of costly amine emission reduction measures.
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Affiliation(s)
- Magnus D Norling
- Norwegian Institute for Water Research (NIVA), Økernveien 94, 0579 Oslo, Norway
| | - François Clayer
- Norwegian Institute for Water Research (NIVA), Økernveien 94, 0579 Oslo, Norway
| | - Cathrine B Gundersen
- Norwegian Institute for Water Research (NIVA), Økernveien 94, 0579 Oslo, Norway.
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5
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Ding S, Deng Y, Bond T, Fang C, Cao Z, Chu W. Disinfection byproduct formation during drinking water treatment and distribution: A review of unintended effects of engineering agents and materials. Water Res 2019; 160:313-329. [PMID: 31154129 DOI: 10.1016/j.watres.2019.05.024] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/06/2019] [Accepted: 05/07/2019] [Indexed: 06/09/2023]
Abstract
Unintended effects of engineering agents and materials on the formation of undesirable disinfection byproducts (DBPs) during drinking water treatment and distribution were comprehensively reviewed. Specially, coagulants, biologically active filtration biofilms, activated carbons, nanomaterials, ion-exchange resins, membrane materials in drinking water treatment and piping materials, deposits and biofilms within drinking water distribution systems were discussed, which may serve as DBP precursors, transform DBPs into more toxic species, and/or catalyze the formation of DBPs. Speciation and quantity of DBPs generated rely heavily on the material characteristics, solution chemistry conditions, and operating factors. For example, quaternary ammonium polymer coagulants can increase concentrations of N-nitrosodimethylamine (NDMA) to above the California notification level (10 ng/L). Meanwhile, the application of strong base ion-exchange resins has been associated with the formation of N-nitrosamines and trichloronitromethane up to concentrations of 400 ng/L and 9.0 μg/L, respectively. Organic compounds leaching from membranes and plastic and rubber pipes can generate high NDMA (180-450 ng/L) and chloral hydrate (∼12.4 μg/L) upon downstream disinfection. Activated carbon and membranes preferentially remove organic precursors over bromide, resulting in a higher proportion of brominated DBPs. Copper corrosion products (CCPs) accelerate the decay of disinfectants and increase the formation of halogenated DBPs. Chlorination of high bromide waters containing CCPs can form bromate at concentrations exceeding regulatory limits. Owing to the aforementioned concern for the drinking water quality, the application of these materials and reagents during drinking water treatment and distribution should be based on the removal of pollutants with consideration for balancing DBP formation during disinfection scenarios. Overall, this review highlights situations in which the use of engineering agents and materials in drinking water treatment and distribution needs balance against deleterious impacts on DBP formation.
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Affiliation(s)
- Shunke Ding
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
| | - Yang Deng
- Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ, 07043, USA
| | - Tom Bond
- Department of Civil and Environmental Engineering, University of Surrey, Guildford, GU2 7XH, UK
| | - Chao Fang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
| | - Zhongqi Cao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
| | - Wenhai Chu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
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6
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Beita-Sandí W, Selbes M, Kim D, Karanfil T. Removal of N-nitrosodimethylamine precursors by cation exchange resin: The effects of pH and calcium. Chemosphere 2018; 211:1091-1097. [PMID: 30223324 DOI: 10.1016/j.chemosphere.2018.08.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/08/2018] [Accepted: 08/09/2018] [Indexed: 06/08/2023]
Abstract
Cation exchange resins have proved to be efficient in removing precursors of N-nitrosodimethylamine (NDMA). NDMA is a probable human carcinogen with a calculated lifetime cancer risk of 10-6 at 0.7 ng/L in drinking water. This paper investigated the effect of pH and calcium levels on the removal of NDMA precursors using a cation exchange resin. At pH 5 and 7, 30-50% of NDMA precursors, measured by formation potentials (FPs) changes before and after the treatment, were removed by Plus resin. However, increases in NDMA FPs were observed after the treatment at pH 10 indicating that NDMA precursors were released from the resin. NDMA FPs removals in samples containing 15 and 115 mg/L Ca2+ were 40% and -10% after the ion exchange treatments at pH 7, respectively. It was found that in the presence of high concentration of calcium only one out of four cation exchange resins released NDMA precursors (probably due to manufacturing impurities). Also, the release of NDMA precursors depended on the calcium concentration and the contact time of the resin with the solution containing calcium. Nonetheless, NDMA precursors release from the resin subsided significantly with increasing the number of regeneration cycles of the resin.
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Affiliation(s)
- Wilson Beita-Sandí
- Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC, 29625, USA; Research Center of Environmental Pollution (CICA), University of Costa Rica, 2060, San José, Costa Rica.
| | - Meric Selbes
- Hazen and Sawyer, Environmental Engineers and Scientists, Fairfax, VA, 22030, USA
| | - Daekyun Kim
- Research Center of Environmental Pollution (CICA), University of Costa Rica, 2060, San José, Costa Rica
| | - Tanju Karanfil
- Research Center of Environmental Pollution (CICA), University of Costa Rica, 2060, San José, Costa Rica
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7
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Beita-Sandí W, Karanfil T. Removal of both N-nitrosodimethylamine and trihalomethanes precursors in a single treatment using ion exchange resins. Water Res 2017; 124:20-28. [PMID: 28734959 DOI: 10.1016/j.watres.2017.07.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 06/12/2017] [Accepted: 07/13/2017] [Indexed: 06/07/2023]
Abstract
Drinking water utilities are relying more than ever on water sources impacted by wastewater effluents. Disinfection/oxidation of these waters during water treatment may lead to the formation of several disinfection by-products, including the probable human carcinogen N-nitrosodimethylamine (NDMA) and the regulated trihalomethanes (THMs). In this study, the potential of ion exchange resins to control both NDMA and THMs precursors in a single treatment is presented. Two ion exchange resins were examined, a cation exchange resin (Plus) to target NDMA precursors and an anion exchange resin (MIEX) for THMs precursors control. We applied the resins, individually and combined, in the treatment of surface and wastewater effluent samples. The treatment with both resins removed simultaneously NDMA (43-85%) and THMs (39-65%) precursors. However, no removal of NDMA precursors was observed in the surface water with low initial NDMA FP (14 ng/L). The removals of NDMA FP and THMs FP with Plus and MIEX resins applied alone were (49-90%) and (41-69%), respectively. These results suggest no interaction between the resins, and thus the feasibility of effectively controlling NDMA and THMs precursors concomitantly. Additionally, the effects of the wastewater impact and the natural attenuation of precursors were studied. The results showed that neither the wastewater content nor the attenuation of the precursor affected the removals of NDMA and THMs precursors. Finally, experiments using a wastewater effluent sample showed that an increase in the calcium concentration resulted in a reduction in the removal of NDMA precursors of about 50%.
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Affiliation(s)
- Wilson Beita-Sandí
- Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC, 29625, USA; Research Center of Environmental Pollution (CICA), University of Costa Rica, 2060, San José, Costa Rica
| | - Tanju Karanfil
- Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC, 29625, USA.
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9
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Zeng T, Glover CM, Marti EJ, Woods-Chabane GC, Karanfil T, Mitch WA, Dickenson ERV. Relative Importance of Different Water Categories as Sources of N-Nitrosamine Precursors. Environ Sci Technol 2016; 50:13239-13248. [PMID: 27993049 DOI: 10.1021/acs.est.6b04650] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A comparison of loadings of N-nitrosamines and their precursors from different source water categories is needed to design effective source water blending strategies. Previous research using Formation Potential (FP) chloramination protocols (high dose and prolonged contact times) raised concerns about precursor loadings from various source water categories, but differences in the protocols employed rendered comparisons difficult. In this study, we applied Uniform Formation Condition (UFC) chloramination and ozonation protocols mimicking typical disinfection practice to compare loadings of ambient specific and total N-nitrosamines as well as chloramine-reactive and ozone-reactive precursors in 47 samples, including 6 pristine headwaters, 16 eutrophic waters, 4 agricultural runoff samples, 9 stormwater runoff samples, and 12 municipal wastewater effluents. N-Nitrosodimethylamine (NDMA) formation from UFC and FP chloramination protocols did not correlate, with NDMA FP often being significant in samples where no NDMA formed under UFC conditions. N-Nitrosamines and their precursors were negligible in pristine headwaters. Conventional, and to a lesser degree, nutrient removal wastewater effluents were the dominant source of NDMA and its chloramine- and ozone-reactive precursors. While wastewater effluents were dominant sources of TONO and their precursors, algal blooms, and to a lesser degree agricultural or stormwater runoff, could be important where they affect a major fraction of the water supply.
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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
- Department of Civil and Environmental Engineering, Syracuse University , 151 Link Hall, Syracuse, New York 13244, United States
| | - Caitlin M Glover
- Water Quality Research and Development Division, Southern Nevada Water Authority , Henderson, Nevada 89015, United States
| | - Erica J Marti
- Water Quality Research and Development Division, Southern Nevada Water Authority , Henderson, Nevada 89015, United States
| | - Gwen C Woods-Chabane
- Water Quality Research and Development Division, Southern Nevada Water Authority , Henderson, Nevada 89015, United States
- HDR, Inc., 431 W Baseline Road, Claremont, California 91711, United States
| | - Tanju Karanfil
- Department of Environmental Engineering and Earth Sciences, Clemson University , 342 Computer Court, Anderson, South Carolina 29625, 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
| | - Eric R V Dickenson
- Water Quality Research and Development Division, Southern Nevada Water Authority , Henderson, Nevada 89015, United States
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10
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Liew D, Linge KL, Joll CA. Formation of nitrogenous disinfection by-products in 10 chlorinated and chloraminated drinking water supply systems. Environ Monit Assess 2016; 188:518. [PMID: 27523603 DOI: 10.1007/s10661-016-5529-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 08/03/2016] [Indexed: 06/06/2023]
Abstract
The presence of nitrogenous disinfection by-products (N-DBPs) in drinking water supplies is a public health concern, particularly since some N-DBPs have been reported to be more toxic than the regulated trihalomethanes and haloacetic acids. In this paper, a comprehensive evaluation of the presence of N-DBPs in 10 drinking water supply systems in Western Australia is presented. A suite of 28 N-DBPs, including N-nitrosamines, haloacetonitriles (HANs), haloacetamides (HAAms) and halonitromethanes (HNMs), were measured and evaluated for relationships with bulk parameters in the waters before disinfection. A number of N-DBPs were frequently detected in disinfected waters, although at generally low concentrations (<10 ng/L for N-nitrosamines and <10 μg/L for other N-DBPs) and below health guideline values where they exist. While there were no clear relationships between N-DBP formation and organic nitrogen in the pre-disinfection water, N-DBP concentrations were significantly correlated with dissolved organic carbon (DOC) and ammonia, and these, in addition to high bromide in one of the waters, led to elevated concentrations of brominated HANs (26.6 μg/L of dibromoacetonitrile). There were significant differences in the occurrence of all classes of N-DBPs between chlorinated and chloraminated waters, except for HNMs, which were detected at relatively low concentrations in both water types. Trends observed in one large distribution system suggest that N-DBPs can continue to form or degrade within distribution systems, and redosing of disinfectant may cause further by-product formation.
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Affiliation(s)
- Deborah Liew
- Curtin Water Quality Research Centre, Department of Chemistry, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia.
| | - Kathryn L Linge
- Curtin Water Quality Research Centre, Department of Chemistry, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia
| | - Cynthia A Joll
- Curtin Water Quality Research Centre, Department of Chemistry, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia
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11
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Woods GC, Sadmani AHMA, Andrews SA, Bagley DM, Andrews RC. Rejection of pharmaceutically-based N-nitrosodimethylamine precursors using nanofiltration. Water Res 2016; 93:179-186. [PMID: 26905796 DOI: 10.1016/j.watres.2016.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 02/03/2016] [Accepted: 02/03/2016] [Indexed: 06/05/2023]
Abstract
N-Nitrosodimethylamine (NDMA) is a disinfection by-product (DBP) with many known precursors such as amine-containing pharmaceuticals that can enter the environment via treated wastewater. Reverse osmosis and tight nanofiltration membranes (MW cutoff < 200 Da) are treatment technologies that demonstrate high removal of many compounds, but at relatively high energy costs. Looser membranes (>200 Da) may provide sufficient removal of a wide range of contaminants with lower energy costs. This study examined the rejection of pharmaceuticals that are known NDMA precursors (∼300 Da) using nanofiltration (MW cutoff ∼350 Da). MQ water was compared to two raw water sources, and results illustrated that NDMA precursors (as estimated by formation potential testing) were effectively rejected in all water matrices (>84%). Mixtures of pharmaceuticals vs. single-spiked compounds were found to have no impact on rejection from the membranes used. The use of MQ water vs. surface waters illustrated that natural organic matter, colloids, and inorganic ions present did not significantly impact the rejection of the amine-containing pharmaceuticals. This study illustrates that NDMA formation potential testing can be effectively used for assessing NDMA precursor rejection from more complex samples with multiple and/or unknown NDMA precursors present, such as wastewater matrices.
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Affiliation(s)
- Gwen C Woods
- Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada.
| | - A H M Anwar Sadmani
- Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada; Department of Civil, Environmental & Construction Engineering, University of Central Florida, 12760 Pegasus Drive, Orlando, FL 32816, United States
| | - Susan A Andrews
- Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada
| | - David M Bagley
- Department of Chemical Engineering, University of Wyoming, Dept. 3295, 1000 E. University Avenue, Laramie, WY 82071, United States
| | - Robert C Andrews
- Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada
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12
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Bazri MM, Martijn B, Kroesbergen J, Mohseni M. Impact of anionic ion exchange resins on NOM fractions: Effect on N-DBPs and C-DBPs precursors. Chemosphere 2016; 144:1988-1995. [PMID: 26547880 DOI: 10.1016/j.chemosphere.2015.10.086] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 10/19/2015] [Accepted: 10/21/2015] [Indexed: 06/05/2023]
Abstract
The formation potential of carbonaceous and nitrogenous disinfection by-products (C-DBPs, N-DBPs) after ion exchange treatment (IEX) of three different water types in multiple consecutive loading cycles was investigated. Liquid chromatography with organic carbon detector (LC-OCD) was employed to gauge the impact of IEX on different natural organic matter (NOM) fractions and data obtained were used to correlate these changes to DBPs Formation Potential (FP) under chlorination. Humic (-like) substances fractions of NOM were mainly targeted by ion exchange resins (40-67% removal), whereas hydrophilic, non-ionic fractions such as neutrals and building blocks were poorly removed during the treatment (12-33% removal). Application of ion exchange resins removed 13-20% of total carbonaceous DBPs FP and 3-50% of total nitrogenous DBPs FP. Effect of the inorganic nitrogen (i.e., Nitrate) presence on N-DBPs FP was insignificant while the presence of dissolved organic nitrogen (DON) was found to be a key parameter affecting the formation of N-DBPs. DON especially the portion affiliated with humic substances fraction, was reduced effectively (∼77%) as a result of IEX treatment.
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Affiliation(s)
- Mohammad Mahdi Bazri
- Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, Canada
| | | | | | - Madjid Mohseni
- Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, Canada.
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13
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McCurry DL, Krasner SW, von Gunten U, Mitch WA. Determinants of disinfectant pretreatment efficacy for nitrosamine control in chloraminated drinking water. Water Res 2015; 84:161-170. [PMID: 26232674 DOI: 10.1016/j.watres.2015.07.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Revised: 06/29/2015] [Accepted: 07/14/2015] [Indexed: 06/04/2023]
Abstract
Utilities using chloramines need strategies to mitigate nitrosamine formation to meet potential future nitrosamine regulations. The ability to reduce NDMA formation under typical post-chloramination conditions of pretreatment with ultraviolet light from a low pressure mercury lamp (LPUV), free chlorine (HOCl), ozone (O3), and UV light from a medium pressure mercury lamp (MPUV) were compared at exposures relevant to drinking water treatment. The order of efficacy after application to waters impacted by upstream wastewater discharges was O3 > HOCl ≈ MPUV > LPUV. NDMA precursor abatement generally did not correlate well between oxidants, and waters exhibited different behaviors with respect to pH and temperature, suggesting a variety of source-dependent NDMA precursors. For wastewater-impacted waters, the observed pH dependence for precursor abatement suggested the important role of secondary or tertiary amine precursors. Although hydroxyl radicals did not appear to be important for NDMA precursor abatement during O3 or MPUV pretreatment, the efficacy of MPUV correlated strongly with dissolved organic carbon concentration (p = 0.01), suggesting alternative indirect photochemical pathways. The temperature dependences during pre- and post-disinfection indicated that NDMA formation is likely to increase during warm seasons for O3 pretreatment, decrease for HOCl pretreatment, and remain unchanged for MPUV treatment, although seasonal changes in source water quality may counteract the temperature effects. For two waters impacted by relatively high polyDADMAC coagulant doses, pretreatment with HOCl, O3, and MPUV increased NDMA formation during post-chloramination. For O3 pretreatment, hydroxyl radicals likely led to precursor formation from the polymer in the latter tests. MPUV treatment of polymer-impacted water increased subsequent NDMA formation through an indirect photochemical process. Many factors may mitigate the importance of this increased NDMA formation, including the low polyDADMAC doses typically applied, and simultaneous degradation of watershed-associated precursors.
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Affiliation(s)
- Daniel L McCurry
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA
| | - Stuart W Krasner
- Metropolitan Water District of Southern California, La Verne, CA 91750, USA
| | - 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 Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - William A Mitch
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA.
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14
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Woods GC, Trenholm RA, Hale B, Campbell Z, Dickenson ERV. Seasonal and spatial variability of nitrosamines and their precursor sources at a large-scale urban drinking water system. Sci Total Environ 2015; 520:120-126. [PMID: 25804879 DOI: 10.1016/j.scitotenv.2015.03.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 03/02/2015] [Accepted: 03/03/2015] [Indexed: 06/04/2023]
Abstract
Nitrosamines are considered to pose greater health risks than currently regulated DBPs and are subsequently listed as a priority pollutant by the EPA, with potential for future regulation. Denver Water, as part of the EPA's Unregulated Contaminant Monitoring Rule 2 (UCMR2) monitoring campaign, found detectable levels of N-nitrosodimethylamine (NDMA) at all sites of maximum residency within the distribution system. To better understand the occurrence of nitrosamines and nitrosamine precursors, Denver Water undertook a comprehensive year-long monitoring campaign. Samples were taken every two weeks to monitor for NDMA in the distribution system, and quarterly sampling events further examined 9 nitrosamines and nitrosamine precursors throughout the treatment and distribution systems. NDMA levels within the distribution system were typically low (>1.3 to 7.2 ng/L) with a remote distribution site (frequently >200 h of residency) experiencing the highest concentrations found. Eight other nitrosamines (N-nitrosomethylethylamine, N-nitrosodiethylamine, N-nitroso-di-n-propylamine, N-nitroso-di-n-butylamine, N-nitroso-di-phenylamine, N-nitrosopyrrolidine, N-nitrosopiperidine, N-nitrosomorpholine) were also monitored but none of these 8, or precursors of these 8 [as estimated with formation potential (FP) tests], were detected anywhere in raw, partially-treated or distribution samples. Throughout the year, there was evidence that seasonality may impact NDMA formation, such that lower temperatures (~5-10°C) produced greater NDMA than during warmer months. The year of sampling further provided evidence that water quality and weather events may impact NDMA precursor loads. Precursor loading estimates demonstrated that NDMA precursors increased during treatment (potentially from cationic polymer coagulant aids). The precursor analysis also provided evidence that precursors may have increased further within the distribution system itself. This comprehensive study of a large-scale drinking water system provides insight into the variability of NDMA occurrence in a chloraminated system, which may be impacted by seasonality, water quality changes and/or the varied origins of NDMA precursors within a given system.
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Affiliation(s)
- Gwen C Woods
- Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193-9954, USA.
| | - Rebecca A Trenholm
- Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193-9954, USA
| | - Bruce Hale
- Denver Water, 1600 West 12th Avenue, Denver, CO 80204-3412, USA
| | - Zeke Campbell
- Denver Water, 1600 West 12th Avenue, Denver, CO 80204-3412, USA
| | - Eric R V Dickenson
- Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193-9954, USA.
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15
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Park SH, Padhye LP, Wang P, Cho M, Kim JH, Huang CH. N-nitrosodimethylamine (NDMA) formation potential of amine-based water treatment polymers: Effects of in situ chloramination, breakpoint chlorination, and pre-oxidation. J Hazard Mater 2015; 282:133-40. [PMID: 25112551 DOI: 10.1016/j.jhazmat.2014.07.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 07/18/2014] [Accepted: 07/21/2014] [Indexed: 05/11/2023]
Abstract
Recent studies show that cationic amine-based water treatment polymers may be important precursors that contribute to formation of the probable human carcinogen N-nitrosodimethylamine (NDMA) during water treatment and disinfection. To better understand how water treatment parameters affect NDMA formation from the polymers, the effects of in situ chloramination, breakpoint chlorination, and pre-oxidation on the NDMA formation from the polymers were investigated. NDMA formation potential (NDMA-FP) as well as dimethylamine (DMA) residual concentration were measured from poly(epichlorohydrin dimethylamine) (polyamine) and poly(diallyldimethylammonium chloride) (polyDADMAC) solutions upon reactions with oxidants including free chlorine, chlorine dioxide, ozone, and monochloramine under different treatment conditions. The results supported that dichloramine (NHCl2) formation was the critical factor affecting NDMA formation from the polymers during in situ chloramination. The highest NDMA formation from the polymers occurred near the breakpoint of chlorination. Polymer chain breakdown and transformation of the released DMA and other intermediates were important factors affecting NDMA formation from the polymers in pre-oxidation followed by post-chloramination. Pre-oxidation generally reduced NDMA-FP of the polymers; however, the treatments involving pre-ozonation increased polyDADMAC's NDMA-FP and DMA release. The strategies for reducing NDMA formation from the polymers may include the avoidance of the conditions favorable to NHCl2 formation and the avoidance of polymer exposure to strong oxidants such as ozone.
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Affiliation(s)
- Sang Hyuck Park
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; School of Science and Technology, Georgia Gwinnett College, Lawrenceville, GA 30043, USA
| | - Lokesh P Padhye
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; Centre for Environmental Science and Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Pei Wang
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Min Cho
- Advanced Institute of Environmental Bioscience, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan, Jeonbok 570-752, South Korea
| | - Jae-Hong Kim
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Ching-Hua Huang
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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16
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Affiliation(s)
- Susan D. Richardson
- Department of Chemistry and Biochemistry, University of South Carolina, JM Palms Center, 631 Sumter Street, Columbia, South Carolina 29208
- Department of Environmental Chemistry, Institute for Environmental Assessment and Water Research, (IDAEA-CSIC), Carrer Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Cristina Postigo
- Department of Chemistry and Biochemistry, University of South Carolina, JM Palms Center, 631 Sumter Street, Columbia, South Carolina 29208
- Department of Environmental Chemistry, Institute for Environmental Assessment and Water Research, (IDAEA-CSIC), Carrer Jordi Girona 18-26, 08034 Barcelona, Spain
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17
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18
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Lindahl S, Gundersen CB, Lundanes E. A review of available analytical technologies for qualitative and quantitative determination of nitramines. Environ Sci Process Impacts 2014; 16:1825-1840. [PMID: 24898740 DOI: 10.1039/c4em00095a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This review aims to summarize the available analytical methods in the open literature for the determination of some aliphatic and cyclic nitramines. Nitramines covered in this review are the ones that can be formed from the use of amines in post-combustion CO2 capture (PCC) plants and end up in the environment. Since the literature is quite scarce regarding the determination of nitramines in aqueous and soil samples, methods for determination of nitramines in other matrices have also been included. Since the nitramines are found in complex matrices and/or in very low concentration, an extraction step is often necessary before their determination. Liquid-liquid extraction (LLE) using dichloromethane and solid phase extraction (SPE) with an activated carbon based material have been the two most common extraction methods. Gas chromatography (GC) or reversed phase liquid chromatography (RPLC) has been used often combined with mass spectrometry (MS) in the final determination step. Presently there is no comprehensive method available that can be used for determination of all nitramines included in this review. The lowest concentration limit of quantification (cLOQ) is in the ng L(-1) range, however, most methods appear to have a cLOQ in the μg L(-1) range, if the cLOQ has been given.
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Affiliation(s)
- Sofia Lindahl
- University of Oslo, Department of Chemistry, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway.
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19
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Chen C, Leavey S, Krasner SW, Mel Suffet IH. Applying polarity rapid assessment method and ultrafiltration to characterize NDMA precursors in wastewater effluents. Water Res 2014; 57:115-126. [PMID: 24709532 DOI: 10.1016/j.watres.2014.02.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 02/26/2014] [Accepted: 02/27/2014] [Indexed: 06/03/2023]
Abstract
Certain nitrosamines in water are disinfection byproducts that are probable human carcinogens. Nitrosamines have diverse and complex precursors that include effluent organic matter, some anthropogenic chemicals, and natural (likely non-humic) substances. An easy and selective tool was first developed to characterize nitrosamine precursors in treated wastewaters, including different process effluents. This tool takes advantages of the polarity rapid assessment method (PRAM) and ultrafiltration (UF) (molecular weight distribution) to locate the fractions with the strongest contributions to the nitrosamine precursor pool in the effluent organic matter. Strong cation exchange (SCX) and C18 solid-phase extraction cartridges were used for their high selectivity for nitrosamine precursors. The details of PRAM operation, such as cartridge clean-up, capacity, pH influence, and quality control were included in this paper, as well as the main parameters of UF operation. Preliminary testing of the PRAM/UF method with effluents from one wastewater treatment plant gave very informative results. SCX retained 45-90% of the N-nitrosodimethylamine (NDMA) formation potential (FP)-a measure of the precursors-in secondary and tertiary wastewater effluents. These results are consistent with NDMA precursors likely having a positively charged amine group. C18 adsorbed 30-45% of the NDMAFP, which indicates that a substantial portion of these precursors were non-polar. The small molecular weight (MW) (<1 kDa) and large MW (>10 kDa) fractions obtained from UF were the primary contributors to NDMAFP. The combination of PRAM and UF brings important information on the characteristics of nitrosamine precursors in water with easy operation.
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Affiliation(s)
- Chao Chen
- Dept. of Environ. Health Sciences, School of Public Health, UCLA, CA 90095, USA; School of Environment, Tsinghua University, Beijing 100084, China.
| | - Shannon Leavey
- Dept. of Environ. Health Sciences, School of Public Health, UCLA, CA 90095, USA
| | - Stuart W Krasner
- Metropolitan Water District of Southern California, CA 91750, USA
| | - I H Mel Suffet
- Dept. of Environ. Health Sciences, School of Public Health, UCLA, CA 90095, USA
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20
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Krasner SW, Mitch WA, McCurry DL, Hanigan D, Westerhoff P. Formation, precursors, control, and occurrence of nitrosamines in drinking water: a review. Water Res 2013; 47:4433-50. [PMID: 23764594 DOI: 10.1016/j.watres.2013.04.050] [Citation(s) in RCA: 293] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 04/24/2013] [Accepted: 04/25/2013] [Indexed: 05/11/2023]
Abstract
This review summarizes major findings over the last decade related to nitrosamines in drinking water, with a particular focus on N-nitrosodimethylamine (NDMA), because it is among the most widely detected nitrosamines in drinking waters. The reaction of inorganic dichloramine with amine precursors is likely the dominant mechanism responsible for NDMA formation in drinking waters. Even when occurrence surveys found NDMA formation in chlorinated drinking waters, it is unclear whether chloramination resulted from ammonia in the source waters. NDMA formation has been associated with the use of quaternary amine-based coagulants and anion exchange resins, and wastewater-impaired source waters. Specific NDMA precursors in wastewater-impacted source waters may include tertiary amine-containing pharmaceuticals or other quaternary amine-containing constituents of personal care products. Options for nitrosamine control include physical removal of precursors by activated carbon or precursor deactivation by application of oxidants, particularly ozone or chlorine, upstream of chloramination. Although NDMA has been the most prevalent nitrosamine detected in worldwide occurrence surveys, it may account for only ≈ 5% of all nitrosamines in chloraminated drinking waters. Other significant contributors to total nitrosamines are poorly characterized. However, high levels of certain low molecular weight nitrosamines have been detected in certain Chinese waters suspected to be impaired by industrial effluents. The review concludes by identifying research needs that should be addressed over the next decade.
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Affiliation(s)
- Stuart W Krasner
- Metropolitan Water District of Southern California, 700 Moreno Avenue, La Verne, CA 91750, USA.
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21
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Abstract
Anion exchange resins are important tools for the removal of harmful anionic contaminants from drinking water, but their use has been linked to the presence of carcinogenic nitrosamines in treated drinking water. In bench-scale batch and column experiments, anion exchange resins from a large, representative group were investigated as sources of the nitrosamines N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosodi-n-propylamine (NDPA), and N-nitrosodi-n-butylamine (NDBA) and their precursors. Several resins were found to release high levels (up to >2000 ng/L, orders of magnitude above drinking water regulatory levels) of nitrosamines upon initial rinsing with lab-grade water, with levels subsiding within 50-100 bed volumes of rinsing. Resins released similarly high levels of nitrosamine precursors, with spikes in precursor release triggered by regeneration of resins with sodium chloride or by interruptions in flow resulting in prolonged contact times. Free chlorine or preformed monochloramine in feedwater led to the production of nitrosamines. Resins released different nitrosamines and precursors depending on their functional groups, with some resins releasing as many as three different nitrosamines and their precursors. These findings have significant implications for the pretreatment and appropriate use of anion exchange resins by drinking water utilities and for the production of anion exchange resins by manufacturers.
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Affiliation(s)
- Riley C Flowers
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
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Weidhaas J, Dupont RR. Aerobic biotransformation of N-nitrosodimethylamine and N-nitrodimethylamine in methane and benzene amended soil columns. J Contam Hydrol 2013; 150:45-53. [PMID: 23673086 DOI: 10.1016/j.jconhyd.2013.04.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 04/10/2013] [Accepted: 04/12/2013] [Indexed: 06/02/2023]
Abstract
Aerobic biotransformation of N-nitrosodimethylamine (NDMA), an emerging contaminant of concern, and its structural analog N-nitrodimethylamine (DMN), was evaluated in benzene and methane amended groundwater passed through laboratory scale soil columns. Competitive inhibition models were used to model the kinetics for NDMA and DMN cometabolism accounting for the concurrent degradation of the growth and cometabolic substrates. Transformation capacities for NDMA and DMN with benzene (13 and 23μg (mgcells)(-1)) and methane (0.14 and 8.4μg (mgcells)(-1)) grown cultures, respectively are comparable to those presented in the literature, as were first order endogenous decay rates estimated to be 2.1×10(-2)±1.7×10(-3)d(-1) and 6.5×10(-1)±7.1×10(-1)d(-1) for the methane and benzene amended cultures, respectively. These studies highlight possible attenuation mechanisms and rates for NDMA and DMN biotransformation in aerobic aquifers undergoing active remediation, natural attenuation or managed aquifer recharge with treated wastewater (i.e., reclaimed water).
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Affiliation(s)
- Jennifer Weidhaas
- West Virginia University, Civil and Environmental Engineering, PO Box 6103, Morgantown, WV 26505, United States.
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23
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Abstract
A U.S.-wide occurrence survey conducted as part of the Unregulated Contaminant Monitoring Rule 2 found that N-nitrosodimethylamine (NDMA) was present in 34% of chloraminated drinking water samples but was the most prevalent of the six N-nitrosamines evaluated using U.S. Environmental Protection Agency (EPA) Method 521. If the U.S. EPA considers limiting exposures to N-nitrosamines as a group, a critical question is whether NDMA is the most prevalent N-nitrosamine or whether significant concentrations occur for N-nitrosamines other than those captured by EPA Method 521. A total N-nitrosamine assay was developed and applied to 36 drinking water plant effluents or distribution system samples from 11 utilities, including 9 utilities that practiced chloramination for secondary disinfection. Concurrent application of EPA Method 521 indicated that NDMA was the most prevalent of the Method 521 N-nitrosamines yet accounted for ∼5% of the total N-nitrosamine pool on a median basis. Among eight plant influent waters, NDMA was detected once, while total N-nitrosamines were detected in five samples, suggesting the importance of source water protection. Similar to NDMA, total N-nitrosamine concentrations in source waters increased after chloramination. Chloramines were applied to organic precursors serving as models for pristine natural organic matter, algal exudate, wastewater effluent, and polyDADMAC quaternary amine-based coagulation polymers. While high yields of NDMA were restricted to the wastewater effluent and polyDADMAC, high yields of total N-nitrosamines were observed from the algal exudate, the wastewater effluent, and polyDADMAC. The results suggest that N-nitrosamines as a class may be more prevalent than suggested by occurrence surveys conducted using EPA Method 521.
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Affiliation(s)
- Ning Dai
- Department of Chemical and Environmental Engineering, Yale University, Mason Lab 313b, 9 Hillhouse Ave., New Haven, Connecticut 06520, United States
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24
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Gan X, Karanfil T, Kaplan Bekaroglu SS, Shan J. The control of N-DBP and C-DBP precursors with MIEX®. Water Res 2013; 47:1344-1352. [PMID: 23286988 DOI: 10.1016/j.watres.2012.11.049] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2012] [Revised: 11/27/2012] [Accepted: 11/28/2012] [Indexed: 06/01/2023]
Abstract
The objective of this study was to examine the potential of Magnetic Ion Exchange (MIEX(®)) technology for removing nitrogenous disinfection byproduct (N-DBP) precursors while minimizing carbonaceous DBP (C-DBP) precursors in (i) surface waters, and (ii) effluent impacted waters. Samples were collected from several drinking water source waters and wastewater treatment plant effluents. The effluent impacted source waters were simulated in the laboratory by mixing treated wastewater effluents with the same source water. Formation potential (FP) tests were conducted for regulated trihalomethanes (THMs), haloacetic acids (HAAs), and selected N-DBPs (nitrosamines and halonitromethanes (HNMs)) before and after the MIEX(®) treatment. The MIEX(®) process substantially lowered UV absorbance, total organic carbon, and THM and HAA FPs in all examined water samples, ranging from 39 to 87% reduction. A relatively small portion (9-33%) of HNM precursors was removed by the MIEX(®) treatment. On the other hand, an increase in N-nitrosodimethylamine (NDMA) FP was observed after the MIEX(®) process but only for the effluent impacted waters. Soluble metals, inorganic nitrogen, and bromide in effluent impacted waters did not correlate with the increase in NDMA FP. There was no effect of MIEX(®) treatment on the removal of other nitrosamine species precursors. Simulations of typical water treatment and distribution systems scenarios showed that NDMA concentrations remained below 10 ng/L, when chlorine alone or 40 min chlorine contact time prior to ammonia addition were employed for post-disinfection. However, when chlorine and ammonia were added simultaneously, NDMA concentration reached 36 ng/L for the water tested in the study.
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Affiliation(s)
- Xiaojie Gan
- Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625, USA
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25
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Bond T, Templeton MR, Graham N. Precursors of nitrogenous disinfection by-products in drinking water--a critical review and analysis. J Hazard Mater 2012; 235-236:1-16. [PMID: 22846217 DOI: 10.1016/j.jhazmat.2012.07.017] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 06/20/2012] [Accepted: 07/04/2012] [Indexed: 05/25/2023]
Abstract
In recent years research into the formation of nitrogenous disinfection by-products (N-DBPs) in drinking water - including N-nitrosodimethylamine (NDMA), the haloacetonitriles (HANs), haloacetamides (HAcAms), cyanogen halides (CNX) and halonitromethanes (HNMs) - has proliferated. This is partly due to their high reported toxicity of N-DBPs. In this review paper information about the formation yields of N-DBPs from model precursors, and about environmental precursor occurrence, has been employed to assess the amount of N-DBP formation that is attributable to known precursors. It was calculated that for HANs and HAcAms, the concentrations of known precursors - mainly free amino acids are insufficient to account for the observed concentrations of these N-DBP groups. However, at least in some waters, a significant proportion of CNX and NDMA formation can be explained by known precursors. Identified N-DBP precursors tend to be of low molecular weight and low electrostatic charge relative to bulk natural organic matter (NOM). This makes them recalcitrant to removal by water treatment processes, notably coagulation, as confirmed by a number of bench-scale studies. However, amino acids have been found to be easier to remove during water treatment than would be suggested by the known molecular properties of the individual free amino acids.
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Affiliation(s)
- Tom Bond
- Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ, United Kingdom.
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Jurado-Sánchez B, Ballesteros E, Gallego M. Occurrence of aromatic amines and N-nitrosamines in the different steps of a drinking water treatment plant. Water Res 2012; 46:4543-4555. [PMID: 22703862 DOI: 10.1016/j.watres.2012.05.039] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Revised: 05/15/2012] [Accepted: 05/19/2012] [Indexed: 06/01/2023]
Abstract
The occurrence of 24 amines within a full scale drinking water treatment plant that used chlorinated agents as disinfectants was evaluated for the first time in this research. Prior to any treatment (raw water), aniline, 3-chloroaniline, 3,4-dichloroaniline and N-nitrosodimethylamine were detected at low levels (up to 18 ng/L) but their concentration increased ∼10 times after chloramination while 9 new amines were produced (4 aromatic amines and 5 N-nitrosamines). Within subsequent treatments, there were no significant changes in the amine levels, although the concentrations of 2-nitroaniline, N-nitrosodimethylamine and N-nitrosodiethylamine increased slightly within the distribution system. Eleven of the 24 amines studied were undetected either in the raw and in the treatment plant samples analysed. There is an important difference in the behaviour of the aromatic amines and N-nitrosamines with respect to water temperature and rainfall events. Amine concentrations were higher in winter due to low water temperatures, this effect being more noticeable for N-nitrosamines. Aromatic amines were detected at their highest concentrations (especially 3,4-dichloroaniline and 2-nitroaniline) in treated water after rainfall events. These results may be explained by the increase in the levels of amine precursors (pesticides and their degradation products) in raw water since the rainfall facilitated the transport of these compounds from soil which was previously contaminated as a result of intensive agricultural practices.
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Affiliation(s)
- Beatriz Jurado-Sánchez
- Department of Analytical Chemistry, Campus of Rabanales, University of Córdoba, E-14071 Córdoba, Spain
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Mcdonald JA, Harden NB, Nghiem LD, Khan SJ. Analysis of N-nitrosamines in water by isotope dilution gas chromatography–electron ionisation tandem mass spectrometry. Talanta 2012; 99:146-54. [DOI: 10.1016/j.talanta.2012.05.032] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 05/17/2012] [Accepted: 05/18/2012] [Indexed: 11/21/2022]
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Affiliation(s)
- Chao-An Chili
- School of Sustainable Engineering and the Built Environment, Ira A. Fulton Schools of Engineering, Arizona State University; Tempe Ariz
| | - Paul Westerhoff
- School of Sustainable Engineering and the Built Environment, Ira A. Fulton Schools of Engineering, Arizona State University; Tempe Ariz
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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. Environ Sci Technol 2012; 46:4809-4818. [PMID: 22463122 DOI: 10.1021/es204717j] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
| | - Nicole K. Blute
- Malcolm Pirnie, the Water Division of ARCADIS; Los Angeles Calif
| | | | - Xueying Wu
- Malcolm Pirnie, the Water Division of ARCADIS; Los Angeles Calif
| | - Zaid Chowdhury
- Malcolm Pirnie, the Water Division of ARCADIS; Phoenix Ariz
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Shah AD, Mitch WA. Halonitroalkanes, halonitriles, haloamides, and N-nitrosamines: a critical review of nitrogenous disinfection byproduct formation pathways. Environ Sci Technol 2012; 46:119-31. [PMID: 22112205 DOI: 10.1021/es203312s] [Citation(s) in RCA: 426] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Interest in the formation of nitrogenous disinfection byproducts (N-DBPs) has increased because toxicological research has indicated that they are often more genotoxic, cytotoxic, or carcinogenic than many of the carbonaceous disinfection byproducts (C-DBPs) that have been a focus for previous research. Moreover, population growth has forced utilities to exploit source waters impaired by wastewater effluents or algal blooms. Both waters feature higher levels of organic nitrogen, that might serve as N-DBP precursors. Utilities are exploring new disinfectant combinations to reduce the formation of regulated trihalomethanes and haloacetic acids. As some of these new combinations may promote N-DBP formation, characterization of N-DBP formation pathways is needed. Formation pathways for halonitroalkanes, halonitriles, haloamides, and N-nitrosamines associated with chlorine, ozone, chlorine dioxide, UV, and chloramine disinfection are critically reviewed. Several important themes emerge from the review. First, the formation pathways of the N-DBP families are partially linked because most of the pathways involve similar amine precursors. Second, it is unlikely that a disinfection scheme that is free of byproduct formation will be discovered. Disinfectant combinations should be optimized to reduce the overall exposure to toxic byproducts. Third, the understanding of formation pathways should be employed to devise methods of applying disinfectants that minimize byproduct formation while accomplishing pathogen reduction goals. Fourth, the well-characterized nature of the monomers constituting the biopolymers that likely dominate the organic nitrogen precursor pool should be exploited to predict the formation of byproducts likely to form at high yields.
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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, United States
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Affiliation(s)
- Susan D Richardson
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Athens, Georgia 30605, USA
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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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Smith EM, Plewa MJ, Lindell CL, Richardson SD, Mitch WA. Comparison of byproduct formation in waters treated with chlorine and iodine: relevance to point-of-use treatment. Environ Sci Technol 2010; 44:8446-8452. [PMID: 20964286 DOI: 10.1021/es102746u] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Due to their efficacy in deactivating a range of microbial pathogens, particularly amoebic cysts, iodine-based disinfectants have been a popular option for point-of-use (POU) drinking water disinfection by campers, the military, and rural consumers in developing countries. Recently, concerns regarding the formation of cytotoxic and genotoxic iodinated disinfection byproducts (I-DBPs) have arisen during chloramine disinfection of iodide-containing waters in the developed world; similar concerns should pertain to iodine-based POU disinfection. Because there are alternative POU disinfection techniques, including chlorine-based disinfectants, this paper compared disinfection byproduct formation from a range of iodine-based disinfectants at their recommended dosages to chlorination and chloramination under overdosing conditions. Just as chloroform was the predominant trihalomethane (THM) forme during chlorination or chloramination, iodoform was the predominant THM formed during iodination. Conditions fostering THM formation were similar between these treatments, except that THM formation during chlorination increased with pH, while it was slightly elevated at circumneutral pH during iodination. Iodoform formation during treatment with iodine tincture was higher than during treatment with iodine tablets. On a molar basis, iodoform formation during treatment with iodine tincture was 20-60% of the formation of chloroform during chlorination, and total organic iodine (TOI) formation was twice that of total organic chlorine (TOCl), despite the 6-fold higher oxidant dose during chlorination. Based upon previous measurements of chronic mammalian cell cytotoxicity for the individual THMs, consumers of two waters treated with iodine tincture would receive the same THM-associated cytotoxic exposure in 4-19 days as a consumer of the same waters treated with a 6-fold higher dose of chlorine over 1 year. Iodoacetic acid, diiodoacetic acid, and other iodo-acids were also formed with iodine tincture treatment, but at levels <11% of iodoform. However, testing of a Lifestraw Personal POU device, which combines an iodinated anion exchange resin with activated carbon post-treatment, indicated minimal formation of I-DBPs and no iodine residual. Although N-nitrosamines have been associated with oxidant contact with anion exchange resins, N-nitrosamine formation rapidly declined to low levels (4 ng/L) using the Lifestraw device after the first few flushes of water.
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Affiliation(s)
- Emma Marie Smith
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520, USA
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Krauss M, Longrée P, van Houtte E, Cauwenberghs J, Hollender J. Assessing the fate of nitrosamine precursors in wastewater treatment by physicochemical fractionation. Environ Sci Technol 2010; 44:7871-7877. [PMID: 20849063 DOI: 10.1021/es101289z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Source control or elimination of precursors of NDMA and other nitrosamines in wastewater requires information on their physicochemical properties, which is still limited. Thus we developed a multistep fractionation method based on a combination of consecutive filtration steps to <1 μm, <0.2 μm, and <2.5 kDa followed by solid-phase extraction on a C18 column and validated it using model NDMA precursors covering a wide polarity range. The membrane filtration to <2.5 kDa was suitable to separate a low-molecular weight precursor fraction but partially removed hydrophobic compounds by sorption. Fractionation on a C18 column allowed distinguishing highly polar precursors (such as dimethylamine) from less polar ones (such as ranitidine or other pharmaceuticals). Application of the fractionation procedure together with the formation potential test revealed that in the influent of one studied wastewater treatment plant about 50% of all precursors were associated with colloids or macromolecules, suggesting that these fractions comprise sorbed hydrophobic precursors. During activated sludge treatment small polar and charged NDMA and other nitrosamines' precursors were removed to about 80%. In contrast, less polar precursors were more recalcitrant. In advanced treatment steps, only small fractions of the precursors were removed by the prechlorination/ultrafiltration step, while reverse osmosis removed >98% of all precursors.
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Affiliation(s)
- Martin Krauss
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, CH-8600 Dübendorf, Switzerland.
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Affiliation(s)
- Susan D. Richardson
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Athens, Georgia 30605
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Abstract
Nitrosamine formation has been associated with wastewater-impacted waters, but specific precursors within wastewater effluents have not been identified. Experiments indicated that nitrosamines form in low yields from quaternary amines, and that the nitrosamines form from the quaternary amines themselves, not just lower order amine impurities. Polymeric and benzylated quaternary amines were more potent precursors than monomeric quaternary alkylamines. Pretreatment of quaternary amines with ozone or free chlorine, which deactivate lower order amine impurities, did not significantly reduce nitrosamine formation. The nitrosamine formation pathway is unclear but experiments indicated that transformation of quaternary amines to lower order amine precursors via Hofmann elimination was not involved. Experiments suggest that the pathway may involve quaternary amine degradation by amidogen or chloramino radicals formed from chloramines. Quaternary amines are significant constituents of consumer products, including shampoos, detergents, and fabric softeners. Although quaternary amines may be removed by sedimentation during wastewater treatment, their importance should be evaluated on a case-by-case basis. The high loadings from consumer products may enable the portion not removed to serve as precursors.
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Affiliation(s)
- Jerome M Kemper
- Department of Chemical Engineering, Yale University, New Haven, Connecticut 06520, USA
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Schäfer AI, Mitch W, Walewijk S, Munoz A, Teuten E, Reinhard M. Chapter 7 Micropollutants in Water Recycling: A Case Study of N-Nitrosodimethylamine (NDMA) Exposure from Water versus Food. Sustainable Water for the Future: Water Recycling versus Desalination 2010. [DOI: 10.1016/s1871-2711(09)00207-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Affiliation(s)
- Susan D. Richardson
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Athens, Georgia 30605
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