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Sardana A, Weaver L, Aziz TN. Effects of dissolved organic matter characteristics on the photosensitized degradation of pharmaceuticals in wastewater treatment wetlands. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:805-824. [PMID: 35481471 DOI: 10.1039/d1em00545f] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Wastewater treatment wetlands are aquatic systems where diverse dissolved organic matter (DOM) compositions physically interact. Complex photochemical behaviors ensue, leading to uncertainties in the prediction of indirect photodegradation rates for organic contaminants. Here, we evaluate the photosensitization ability of whole water DOM samples from a treatment wetland and wastewater treatment plant (WWTP) in North Carolina to photodegrade target pharmaceuticals. Optical characterization using ultraviolet-visible and excitation-emission matrix spectroscopy shows that wetland DOM has higher aromaticity than WWTP DOM and that WWTP secondary treatment processes increase aromaticity, overall molecular weight, and humic character of wastewater DOM. Our application of a reversed-phase HPLC method to assess DOM polarity distinctly reveals that a subset of the wetland samples possesses an abundance of hydrophobic DOM moieties. Hydroxyl radicals (˙OH) mediate the majority (>50%) of the indirect photodegradation for amoxicillin (AMX), atenolol (ATL), and 17α-ethinylestradiol (EE2), while singlet oxygen (1O2) is presumed to be solely responsible for the photodegradation of cimetidine (CME). Our findings suggest that hydrophobic interactions and improved accessibility to photogenerated reactive intermediates lead to significant increases in photosensitization efficiencies and overall indirect photodegradation rates of AMX, ATL, and EE2 for the hydrophobic wetland samples. In contrast, CME photosensitization yields are unaffected by polarity and trend positively with optical indicators of sunlight-induced DOM photobleaching and humification, suggesting that wetland processing favors faster 1O2 photogeneration. These relationships highlight the uncertainties in photosensitization yields and effects of DOM optical properties and polarity on the photochemical fate of organic contaminants.
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Affiliation(s)
- Arpit Sardana
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, 3250 Fitts-Woolard Hall, 915 Partners Way, Raleigh NC 27695, USA.
- Geosyntec Consultants Inc., 2501 Blue Ridge Road, Suite 430, Raleigh, NC, 27607, USA
| | - Leah Weaver
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, 3250 Fitts-Woolard Hall, 915 Partners Way, Raleigh NC 27695, USA.
| | - Tarek N Aziz
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, 3250 Fitts-Woolard Hall, 915 Partners Way, Raleigh NC 27695, USA.
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2
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He H, Lin Y, Yang X, Zhu X, Xie W, Lai C, Yang S, Zhang Z, Huang B, Pan X. The photodegradation of 17 alpha-ethinylestradiol in water containing iron and dissolved organic matter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 814:152516. [PMID: 34968604 DOI: 10.1016/j.scitotenv.2021.152516] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
17 alpha-ethinylestradiol (EE2) in natural waters can seriously harm ecosystems and human health. Dissolved organic matter (DOM) and iron minerals are ubiquitous in natural waters, and they can shorten the half-life of EE2 in the natural environment. The interaction between dissolved organics and iron affects pollutants' transformation pathways. The mechanism of EE2's adsorption on hematite, magnetite and pyrite was studied. A photo-Fenton system was constructed in which humic acid (HA) and iron minerals degraded EE2 under simulated natural light conditions. Pyrite showed the best adsorption and degradation in acidic conditions (52%) for 5 h. Hydroxyl radical was found to be the main active substance in the photodegradation. The degradation products of EE2 were identified and possible degradation pathways were inferred. These results can contribute to the understanding of the transformation pathways of persistent organic pollutants in natural waters.
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Affiliation(s)
- Huan He
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Yanting Lin
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Xiaoxia Yang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Xintong Zhu
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Wenxiao Xie
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Chaochao Lai
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Shanshan Yang
- School of Earth and Space Sciences, Peking University, Beijing 100871, China
| | - Zhe Zhang
- Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, OH 45221, USA
| | - Bin Huang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China; Yunnan Provincial Key Laboratory of Carbon Sequestration and Pollution Control in Soils, Kunming 650500, China.
| | - Xuejun Pan
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China; Yunnan Provincial Key Laboratory of Carbon Sequestration and Pollution Control in Soils, Kunming 650500, China.
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3
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Rastogi L, Ankam DP, Yadlapalli S, Dash K. Development of microwave assisted-UV digestion using diluted reagents for the determination of total nitrogen in cereals by ion chromatography. Curr Res Food Sci 2021; 4:421-428. [PMID: 34195623 PMCID: PMC8239805 DOI: 10.1016/j.crfs.2021.06.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 05/21/2021] [Accepted: 06/08/2021] [Indexed: 11/02/2022] Open
Abstract
The objective of this work is to develop a microwave assisted-ultraviolet (MW-UV) digestion in the presence of dilute HCl and H2O2 followed by ion chromatography (IC) measurements for the determination of total nitrogen in cereals. This approach (MW-UV-IC) requires lesser time and does not need environmentally hazardous materials as used in Kjeldhal method. Further, the developed method requires only microliter quantities of dilute HCl and few milliliters of H2O2 for the matrix digestion and simultaneous conversion of nitrogen to its ionic species for the subsequent analysis by IC. At the optimized acid concentrations (200 μL of 0.1 mol L-1 HCl) and microwave power, the nitrogen in the cereals flours is converted to nitrate (NO3 -), nitrite (NO2 -) and ammonium (NH4 +) ions. The nitrogen species were separated using IonPac AS-20 and IonPac CS-17 columns and then quantified using suppressed conductivity detection. The method was applied to estimate the total nitrogen in flours of various cereals like; wheat (Triticum aestivum), rice (Oryza sativa), finger millet (Eleusine coracana), jowar (Sorghum) and pearl millet (Pennisetum glaucum). The results obtained using proposed method, were in good agreement with that of Kjeldhal method. Further, the precision of the values obtained by developed method was on par with the Kjeldhal method for all the tested flours as verified by F-test (n = 5 and 95% confidence limit). Additionally, greenness assessment tools like analytical Eco-scale and green analytical procedure index (GAPI) suggested the proposed MW-UV-IC method, for the determination of total nitrogen in cereal flours, to be excellently green and safe.
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Affiliation(s)
- Lori Rastogi
- National Centre for Compositional Characterization of Materials (NCCCM), Bhabha Atomic Research Centre, ECIL Post, Hyderabad, 500 062, India
| | - Durga Prasad Ankam
- National Centre for Compositional Characterization of Materials (NCCCM), Bhabha Atomic Research Centre, ECIL Post, Hyderabad, 500 062, India
| | - S Yadlapalli
- FirstSource Laboratory Solutions LLP, IDA, Nacharam, Hyderabad, 500 076, India
| | - K Dash
- National Centre for Compositional Characterization of Materials (NCCCM), Bhabha Atomic Research Centre, ECIL Post, Hyderabad, 500 062, India.,Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, 400 094, India
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4
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Liang R, Tang F, Wang J, Yue Y. Photo-degradation dynamics of five neonicotinoids: Bamboo vinegar as a synergistic agent for improved functional duration. PLoS One 2019; 14:e0223708. [PMID: 31622381 PMCID: PMC6797178 DOI: 10.1371/journal.pone.0223708] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 09/26/2019] [Indexed: 11/18/2022] Open
Abstract
The effects of photo-degradation on the utilization of pesticides in agricultural production has been investigated. Various influencing factors were compared, with results showing that the initial pesticide concentration, light source, water quality and pH possessed different effects on neonicotinoids photo-degradation. The initial concentration and pH were found to be most critical effects. The photo-degradation rate decreased by a factor of 2-4 when the initial concentration increased from 5 mg L-1 to 20 mg L-1, particularly for acetamiprid and imidacloprid. The photo-degradation pathways and products of the five neonicotinoids were also investigated, with similar pathways found for each pesticide, except for acetamiprid. Degradation pathways mainly involved photo-oxidation processes, with products identified using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) found to be consistent with literature reported results. Bamboo vinegar exerted a photo-quenching effect on the neonicotinoids, with an improved efficiency at higher vinegar concentrations. The photo-quenching rates of thiamethoxam and dinotefuran were 381.58% and 310.62%, respectively, when a 30-fold dilution of vinegar was employed. The photo-degradation products in bamboo vinegar were identical to those observed in methanol, with acetic acid being the main factor influencing the observed quenching effects.
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Affiliation(s)
- Rui Liang
- School of Resource & Environment, Anhui Agricultural University, Hefei, China
| | - Feng Tang
- State Forestry Administration Key Open Laboratory, International Centre for Bamboo and Rattan, Beijing, China
| | - Jin Wang
- State Forestry Administration Key Open Laboratory, International Centre for Bamboo and Rattan, Beijing, China
| | - Yongde Yue
- State Forestry Administration Key Open Laboratory, International Centre for Bamboo and Rattan, Beijing, China
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Schmitt M, Moor KJ, Erickson PR, McNeill K. Sorbic Acid as a Triplet Probe: Reactivity of Oxidizing Triplets in Dissolved Organic Matter by Direct Observation of Aromatic Amine Oxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:8087-8096. [PMID: 31269391 DOI: 10.1021/acs.est.9b01789] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Sorbic acid (2,4-hexadienoic acid; HDA) isomerization is frequently used to probe triplet-state dissolved organic matter (3CDOM*) reactivity, but there remain open questions about the reaction kinetics of 3CDOM* with HDA due to the difficulties of directly measuring 3CDOM* quenching rate constants. Using our recently developed approach based on observing the radical cation of N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) formed through oxidation of TMPD by 3CDOM*, we studied 3CDOM* quenching kinetics with HDA monitored via transient absorption spectroscopy. A competition kinetics-based approach utilizing formation yields of TMPD•+ was developed, validated with model sensitizers, and used to determine bimolecular rate constants between 3CDOM* oxidants and HDA for diverse DOM isolates and natural waters samples, yielding values in the range of (2.4-7.7) × 108 M-1 s-1. The unquenchable fraction of TMPD-oxidizing triplets showed that, on average, 41% of 3CDOM* oxidants cannot be quenched by HDA. Conversely, cycloheptatriene quenched nearly all TMPD•+-forming triplets in CDOM, suggesting that most 3CDOM* oxidants possess energies greater than 150 kJ mol-1. Comparing results with our companion study, we found slight, but noticeable differences in the 3CDOM* quenching rate constants by HDA and unquenchable triplet fractions determined by oxidation of TMPD and energy transfer to O2 (1O2 formation) methods.
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Affiliation(s)
- Markus Schmitt
- Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environmental Systems Science , ETH Zurich , 8092 Zurich , Switzerland
| | - Kyle J Moor
- Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environmental Systems Science , ETH Zurich , 8092 Zurich , Switzerland
| | - Paul R Erickson
- Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environmental Systems Science , ETH Zurich , 8092 Zurich , Switzerland
| | - Kristopher McNeill
- Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environmental Systems Science , ETH Zurich , 8092 Zurich , Switzerland
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6
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Molé RA, Good CJ, Stebel EK, Higgins JF, Pitell SA, Welch AR, Minarik TA, Schoenfuss HL, Edmiston PL. Correlating effluent concentrations and bench-scale experiments to assess the transformation of endocrine active compounds in wastewater by UV or chlorination disinfection. CHEMOSPHERE 2019; 226:565-575. [PMID: 30953901 DOI: 10.1016/j.chemosphere.2019.03.145] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 03/21/2019] [Accepted: 03/22/2019] [Indexed: 06/09/2023]
Abstract
Transformation of endocrine active compounds (EACs) by either chlorination (Cl-D) or UV disinfection (UV-D) was studied by field sampling and bench-scale validation studies. Field testing assessed concentration of 13 EACs in effluent at two Chicago area 250 MGD wastewater reclamation plants (WRP) over two years. One WRP uses chlorination/dechlorination while the other employs UV disinfection. Target compounds included bupropion, carbamazepine, citalopram, duloxetine, estradiol, estrone, fluoxetine, nonylphenol, norfluoxetine, norsertraline, paroxetine, sertraline, and venlafaxine. Concentrations of 9/13 target compounds were partially reduced after disinfection (5-65% reduction). None of the target compounds were fully transformed by either chlorination or UV treatment at the WRP scale. In bench-scale experiments each compound was spiked into deionized water or effluent and treated in a process mimicking plant-scale disinfection to validate transformations. Correlation was observed between compounds that were transformed in bench-testing and those that decreased in concentration in post-disinfection WRP effluent (10/13 compounds). A survey of potential reaction products was made. Chlorination of some amine containing compounds produced chloramine by-products that reverted to the initial form after dechlorination. Transformation products produced upon simulated UV disinfection were more diverse. Laboratory UV-induced transformation was generally more effective under stirred conditions, suggesting that indirect photo-induced reactions may predominate over direct photolysis.
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Affiliation(s)
- Rachel A Molé
- Department of Chemistry, The College of Wooster, 943 College Mall, Wooster, OH, 44691, USA
| | - Christopher J Good
- Department of Chemistry, The College of Wooster, 943 College Mall, Wooster, OH, 44691, USA
| | - Eva K Stebel
- Department of Chemistry, The College of Wooster, 943 College Mall, Wooster, OH, 44691, USA
| | - Julia F Higgins
- Department of Chemistry, The College of Wooster, 943 College Mall, Wooster, OH, 44691, USA
| | - Sarah A Pitell
- Department of Chemistry, The College of Wooster, 943 College Mall, Wooster, OH, 44691, USA
| | - Arielle R Welch
- Department of Chemistry, The College of Wooster, 943 College Mall, Wooster, OH, 44691, USA
| | - Thomas A Minarik
- Metropolitan Water Reclamation District of Greater Chicago, Cicero, IL, 60804, USA
| | - Heiko L Schoenfuss
- Aquatic Toxicology Laboratory, St. Cloud State University, St. Cloud, Minnesota, 56301, USA
| | - Paul L Edmiston
- Department of Chemistry, The College of Wooster, 943 College Mall, Wooster, OH, 44691, USA.
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7
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He H, Xiong D, Han F, Xu Z, Huang B, Pan X. Dissolved oxygen inhibits the promotion of chlorothalonil photodegradation mediated by humic acid. J Photochem Photobiol A Chem 2018. [DOI: 10.1016/j.jphotochem.2018.04.050] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Vebrosky EN, Saranjampour P, Crosby DG, Armbrust KL. Photodegradation of Dicloran in Freshwater and Seawater. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:2654-2659. [PMID: 29474091 DOI: 10.1021/acs.jafc.8b00211] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Dicloran appears to be a model pesticide for investigating photodegradation processes in surface waters. Photodegradation processes are particularly relevant to this compound as it is applied to crops grown in proximity to freshwater and marine ecosystems. The photodegradation of dicloran under simulated sunlight was measured in distilled water, artificial seawater, phosphate buffer, and filter-sterilized estuarine water to determine its half-life, degradation rate, and photodegradation products. The half-life was approximately 7.5 h in all media. There was no significant difference in the rate of degradation between distilled water and artificial seawater for dicloran. For the intermediate products, a higher concentration of 2-chloro-1,4-benzoquinone was measured in artificial seawater versus distilled water, while a slightly higher concentration of 1,4-benzoquinone was measured in distilled water versus artificial seawater. The detection of chloride and nitrate ions after 2 h of light exposure suggests photonucleophilic substitution contributes to the degradation process. Differences in product distributions between water types suggest that salinity impacts on chemical degradation may need to be addressed in chemical exposure assessments.
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Affiliation(s)
- Emily N Vebrosky
- Department of Environmental Sciences, College of the Coast & Environment , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Parichehr Saranjampour
- Department of Environmental Sciences, College of the Coast & Environment , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Donald G Crosby
- Department of Environmental Toxicology , University of California at Davis , Davis , California 95616 , United States
| | - Kevin L Armbrust
- Department of Environmental Sciences, College of the Coast & Environment , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
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9
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Sun Z, Zhang C, Chen P, Zhou Q, Hoffmann MR. Impact of humic acid on the photoreductive degradation of perfluorooctane sulfonate (PFOS) by UV/Iodide process. WATER RESEARCH 2017; 127:50-58. [PMID: 29031799 DOI: 10.1016/j.watres.2017.10.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 06/07/2023]
Abstract
Iodide photolysis under UV illumination affords an effective method to produce hydrated electrons (eaq-) in aqueous solution. Therefore, UV/Iodide photolysis can be utilized for the reductive degradation of many recalcitrant pollutants. However, the effect of naturally occurring organic matter (NOM) such as humic and fulvic acids (HA/FA), which may impact the efficiency of UV/Iodide photoreduction, is poorly understood. In this study, the UV photoreductive degradation of perfluorooctane sulfonate (PFOS) in the presence of I- and HA is studied. PFOS undergoes a relatively slow direct photoreduction in pure water, a moderate level of degradation via UV/Iodide, but a rapid degradation via UV/Iodide/HA photolysis. After 1.5 h of photolysis, 86.0% of the initial [PFOS] was degraded in the presence of both I- and HA with a corresponding defluorination ratio of 55.6%, whereas only 51.7% of PFOS was degraded with a defluorination ratio of 4.4% via UV/Iodide illumination in the absence of HA. The relative enhancement in the presence of HA in the photodegradation of PFOS can be attributed to several factors: a) HA enhances the effective generation of eaq- due to the reduction of I2, HOI, IO3- and I3- back to I-; b) certain functional groups of HA (i.e., quinones) enhance the electron transfer efficiency as electron shuttles; c) a weakly-bonded association of I- and PFOS with HA increases the reaction probability; and d) absorption of UV photons by HA itself produces eaq-. The degradation and defluorination efficiency of PFOS by UV/Iodide/HA process is dependent on pH and HA concentration. As pH increases from 7.0 to 10.0, the enhancement effect of HA improves significantly. The optimal HA concentration for the degradation of 0.03 mM PFOS is 1.0 mg L-1.
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Affiliation(s)
- Zhuyu Sun
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Chaojie Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Pei Chen
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Qi Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Michael R Hoffmann
- Linde-Robinson Laboratories, California Institute of Technology, Pasadena, CA 91125, United States
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10
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Schmitt M, Erickson PR, McNeill K. Triplet-State Dissolved Organic Matter Quantum Yields and Lifetimes from Direct Observation of Aromatic Amine Oxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:13151-13160. [PMID: 29035568 DOI: 10.1021/acs.est.7b03402] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Excited triplet state chromophoric dissolved organic matter (3CDOM*) is a short-lived mixture of excited-state species that plays important roles in aquatic photochemical processes. Unlike the study of the triplet states of well-defined molecules, which are amenable to transient absorbance spectroscopy, the study of 3CDOM* is hampered by it being a complex mixture and its low average intersystem crossing quantum yield (ΦISC). This study is an alternative approach to investigating 3CDOM* using transient absorption laser spectroscopy. The radical cation of N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD), formed through oxidation by 3CDOM*, was directly observable by transient absorption spectroscopy and was used to probe basic photophysical properties of 3CDOM*. Quenching and control experiments verified that TMPD•+ was formed from 3CDOM* under anoxic conditions. Model triplet sensitizers with a wide range of excited triplet state reduction potentials and CDOM oxidized TMPD at near diffusion-controlled rates. This gives support to the idea that a large cross-section of 3CDOM* moieties are able to oxidize TMPD and that the complex mixture of 3CDOM* can be simplified to a single signal. Using the TMPD•+ transient, the natural triplet lifetime and ΦISC for different DOM isolates and natural waters were quantified; values ranged from 12 to 26 μs and 4.1-7.8%, respectively.
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Affiliation(s)
- Markus Schmitt
- Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environmental Systems Science, ETH Zurich , 8092 Zurich, Switzerland
| | - Paul R Erickson
- Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environmental Systems Science, ETH Zurich , 8092 Zurich, Switzerland
| | - Kristopher McNeill
- Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environmental Systems Science, ETH Zurich , 8092 Zurich, Switzerland
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11
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Yang Y, Li J, Lu K, Shi H, Gao S. Transformation of 17α-ethinylestradiol by simultaneous photo-enzymatic process in Humic water. CHEMOSPHERE 2017; 178:432-438. [PMID: 28342991 DOI: 10.1016/j.chemosphere.2017.03.077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 02/24/2017] [Accepted: 03/19/2017] [Indexed: 06/06/2023]
Abstract
The fate of estrogens in surface water is mainly dependent on two processes, i.e. photodegradation and biotransformation. Each of the separate process is invariably of interest, but research on the combination of the two processes has rarely been explored. In the present work, the transformation of 17α-ethinylestradiol (EE2) by simultaneous photochemical and enzymatic process in water was systematically investigated. The combined transformation rate of EE2 (0.057 h-1) in the presence of natural organic matter (NOM) and horseradish peroxidase (HRP) under simulated sunlight irradiation was markedly faster than that in the presence of NOM only (0.032 h-1). Similar pattern was also observed in real water matrix sampled from Taihu Lake. Further study revealed that the photodegradation and enzymatic transformation of EE2 were dramatically affected by NOM concentrations ranging from 0 to 20 mgC L-1. NOM was found to invariably accelerate the photodegradation of EE2 with increasing concentration. On the contrary, the transformation rate of EE2 mediated by HRP was decreased along with the increase of NOM concentration. The reason may be that HRP was prone to be inactivated in solution with high NOM concentration. The transformation experiment of EE2 at ambient level under sunlight confirmed the significant contribution of HRP to the degradation of EE2 in the presence of NOM. The results indicated that oxidation mediated by HRP was an essential fate of EE2 and other congener contaminants in aquatic environment.
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Affiliation(s)
- Yun Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China
| | - Jianhua Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China
| | - Kun Lu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China
| | - Huanhuan Shi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China
| | - Shixiang Gao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China.
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12
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Ren D, Huang B, Yang B, Chen F, Pan X, Dionysiou DD. Photobleaching alters the photochemical and biological reactivity of humic acid towards 17α-ethynylestradiol. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 220:1386-1393. [PMID: 27825843 DOI: 10.1016/j.envpol.2016.10.096] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 10/21/2016] [Accepted: 10/31/2016] [Indexed: 06/06/2023]
Abstract
Dissolved humic acid (HA) is ubiquitous in natural waters. Its presence significantly changes the photo-and bio-degradation of some organic pollutants in natural waters. The effects of photobleaching on the composition, photosensitizing property and bioavailability of HA were investigated here along with the subsequent influence on its photochemical and biological reactivity in mediating 17α-ethynylestradiol (EE2) degradation. Photobleaching transformed the refractory HA into some small molecules, including organic acids and aliphatics. Along with composition alteration, the photochemical reactivity of HA towards EE2 was slightly depressed, with 9% of the removal rate inhibited by a 70-h photobleaching. Contrarily, the reactivity of HA in mediating EE2 biodegradation by E. coli was significantly promoted by a short-term photobleaching. Compared to the biodegradation of EE2 in the pristine HA, the 10-h photobleached HA increased the biodegradation removal rate of EE2 by 25%, reaching its peak value of about 60%. However, the EE2 biodegradation was inhibited by further irradiation, and the removal rate of EE2 decreased to that in the pristine HA systems. Because no substrate competition was found between EE2 and formate or glucose, EE2 biodegradation mediated by HA in natural waters may not be affected by coexistent organics. Photodegradation and biodegradation of EE2 mediated by HA thus can be combined together by photobleaching to remove pollutants from natural waters. The results reported here could assist environmental risk assessment with respect to EE2 in natural aquatic systems.
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Affiliation(s)
- Dong Ren
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Bin Huang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Benqin Yang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Fang Chen
- College of Environmental Science and Engineering, China West Normal University, Nanchong 637009, China
| | - Xuejun Pan
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China.
| | - Dionysios D Dionysiou
- Department of Biomedical, Chemical, and Environmental Engineering, University of Cincinnati, Cincinnati, OH 45221, USA.
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Trawiński J, Skibiński R. Studies on photodegradation process of psychotropic drugs: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:1152-1199. [PMID: 27696160 PMCID: PMC5306312 DOI: 10.1007/s11356-016-7727-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 09/15/2016] [Indexed: 05/10/2023]
Abstract
Consumption of psychotropic drugs is still increasing, especially in high-income countries. One of the most crucial consequences of this fact is significant release of them to the environment. Considerable amounts of atypical antipsychotics, benzodiazepines, antidepressants, and their metabolites were detected in river, lake, and sea water, as well as in tissues of aquatic organisms. Their ecotoxicity was proved by numerous studies. It should be noticed that interaction between psychotropic pharmaceuticals and radiation may lead to formation of potentially more toxic intermediates. On the other hand, photo-assisted wastewater treatment methods can be used as an efficient way to eliminate them from the environment. Many methods based on photolysis and photocatalysis were proposed and developed recently; nevertheless, the problem is still unsolved. However, according to recent studies, photocatalysis could be considered as the most promising and far more effective than regular photolysis. An overview on photolytic as well as homogenous and heterogeneous photocatalytic degradation methods with the use of various catalysts is presented. The photostability and phototoxicity of pharmaceuticals were also discussed. Various analytical methods were used for the photodegradation research, and this issue was also compared and summarized. Use of high-resolution multistage mass spectrometry (Q-TOF, ion trap, Orbitrap) was suggested. The combined techniques such as LC-MS, GC-MS, and LC-NMR, which enable qualitative and quantitative analyses in one run, proved to be the most valuable in this case. Assembling of MS/MS spectra libraries of drug molecules and their phototransformation products was identified as the future challenge.
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Affiliation(s)
- Jakub Trawiński
- Department of Medicinal, Medical University of Lublin, Jaczewskiego 4, 20-090, Lublin, Poland.
| | - Robert Skibiński
- Department of Medicinal, Medical University of Lublin, Jaczewskiego 4, 20-090, Lublin, Poland
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