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Liu Y, Chen X, Zhao J, Jin W, Zhang K, Qu J, Zhang YN, Chen G, Peijnenburg WJGM. Development of a quantitative structure-activity relationship model for predicting quantum yield of hydroxyl radical generation from organic compounds. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:66-74. [PMID: 36504232 DOI: 10.1039/d2em00396a] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Organic compounds are capable of generating hydroxyl radicals (˙OH) through their excited triplet states in natural water. It is of significance to reveal the underlying mechanism of the generation and obtain the generation quantum yield of ˙OH from organic compounds for better understanding of its involvement in indirect photochemical processes in the environment. In this study, the ˙OH quantum yields (Φ˙OH) of 20 organic compounds were determined by photochemical experiments. The calculated Φ˙OH values for the selected organic compounds vary from (1.2 ± 0.39) × 10-5 to (7.2 ± 0.16) × 10-4. A quantitative structure-activity relationship (QSAR) model for log Φ˙OH was developed and the established model was proven to have a proper goodness of fit, robustness, and predictive ability. The QSAR model was successfully used to predict the Φ˙OH value of organic pollutants. Mechanistic interpretation showed that the electron distribution and the electronegativity of organic compounds are the most important factors that determine the generation of ˙OH. The results are helpful for understanding the generation mechanism of ˙OH from organic compounds and also provide insights into the generation of ˙OH from dissolved organic matter in natural water.
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Affiliation(s)
- Yue Liu
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
| | - Xiaobing Chen
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
| | - Jianchen Zhao
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
| | - Wenjie Jin
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
| | - Kun Zhang
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
| | - Jiao Qu
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
| | - Ya-Nan Zhang
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
| | - Guangchao Chen
- Institute of Environmental Sciences, Leiden University, Leiden, the Netherlands
| | - Willie J G M Peijnenburg
- Institute of Environmental Sciences, Leiden University, Leiden, the Netherlands
- National Institute of Public Health and the Environment (RIVM), Center for Safety of Substances and Products, Bilthoven, the Netherlands
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2
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Jin W, Cheng F, Liu Y, Yang H, Zhou Y, Qu J, Zhang YN. Insights into generation mechanisms of halogen radicals from excited triplet state of dissolved organic matter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 834:155280. [PMID: 35427609 DOI: 10.1016/j.scitotenv.2022.155280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 04/10/2022] [Accepted: 04/10/2022] [Indexed: 06/14/2023]
Abstract
Triplet states of dissolved organic matter (3DOM*) can sensitize the generation of halogen radicals in marine water. The generation pathways of halogen radicals from 3DOM* is still not fully understood. In this study, the generation of halogen radicals from DOM was investigated with Suwanee River fulvic acid (SRFA) as a representative and detailed generation pathways were further revealed with anthraquinone-2-sodium sulfonate (AQ2S) as a triplet sensitizer. The results showed that in SRFA solutions with halogen ions, various halogen radicals can be generated. Among which, Br is formed by the reaction of Br- with 3AQ2S*, and Cl is produced by the reaction of Cl- with AQ2S+ that generated in the presence of dissolved oxygen (DO). Cl2- and Br2- were generated via the subsequent combination of Cl/Br with another Cl-/Br-. In solutions without DO, BrCl- is mainly generated through the combination of Br with Cl-, and BrCl- could also be generated through the combination of Cl with Br- in solutions with DO. This study provides deep insights into the generation mechanisms of different halogen radicals from 3DOM* and is helpful for understanding the photochemical processes of halogen radicals in marine waters.
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Affiliation(s)
- Wenjie Jin
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Fangyuan Cheng
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Yue Liu
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Hao Yang
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Yangjian Zhou
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Jiao Qu
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Ya-Nan Zhang
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, Jilin 130117, China.
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Goia S, Turner MAP, Woolley JM, Horbury MD, Borrill AJ, Tully JJ, Cobb SJ, Staniforth M, Hine NDM, Burriss A, Macpherson JV, Robinson BR, Stavros VG. Ultrafast transient absorption spectroelectrochemistry: femtosecond to nanosecond excited-state relaxation dynamics of the individual components of an anthraquinone redox couple. Chem Sci 2022; 13:486-496. [PMID: 35126981 PMCID: PMC8730129 DOI: 10.1039/d1sc04993c] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/08/2021] [Indexed: 11/21/2022] Open
Abstract
Many photoactivated processes involve a change in oxidation state during the reaction pathway and formation of highly reactive photoactivated species. Isolating these reactive species and studying their early-stage femtosecond to nanosecond (fs-ns) photodynamics can be challenging. Here we introduce a combined ultrafast transient absorption-spectroelectrochemistry (TA-SEC) approach using freestanding boron doped diamond (BDD) mesh electrodes, which also extends the time domain of conventional spectrochemical measurements. The BDD electrodes offer a wide solvent window, low background currents, and a tuneable mesh size which minimises light scattering from the electrode itself. Importantly, reactive intermediates are generated electrochemically, via oxidation/reduction of the starting stable species, enabling their dynamic interrogation using ultrafast TA-SEC, through which the early stages of the photoinduced relaxation mechanisms are elucidated. As a model system, we investigate the ultrafast spectroscopy of both anthraquinone-2-sulfonate (AQS) and its less stable counterpart, anthrahydroquinone-2-sulfonate (AH2QS). This is achieved by generating AH2QS in situ from AQS via electrochemical means, whilst simultaneously probing the associated early-stage photoinduced dynamical processes. Using this approach we unravel the relaxation mechanisms occurring in the first 2.5 ns, following absorption of ultraviolet radiation; for AQS as an extension to previous studies, and for the first time for AH2QS. AQS relaxation occurs via formation of triplet states, with some of these states interacting with the buffered solution to form a transient species within approximately 600 ps. In contrast, all AH2QS undergoes excited-state single proton transfer with the buffered solution, resulting in formation of ground state AHQS- within approximately 150 ps.
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Affiliation(s)
- Sofia Goia
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
- Molecular Analytical Science CDT, Senate House, University of Warwick Coventry CV4 7AL UK
| | - Matthew A P Turner
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
- Molecular Analytical Science CDT, Senate House, University of Warwick Coventry CV4 7AL UK
- Department of Physics, University of Warwick Coventry CV4 7AL UK
| | - Jack M Woolley
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
| | - Michael D Horbury
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
- School of Electronic and Electrical Engineering, University of Leeds LS2 9JT UK
| | - Alexandra J Borrill
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
- Diamond Science and Technology CDT, University of Warwick Coventry CV4 7AL UK
| | - Joshua J Tully
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
- Diamond Science and Technology CDT, University of Warwick Coventry CV4 7AL UK
| | - Samuel J Cobb
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
- Diamond Science and Technology CDT, University of Warwick Coventry CV4 7AL UK
- Department of Chemistry, University of Cambridge Cambridge CB2 1EW UK
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Solomou N, Minella M, Vione D, Psillakis E. UVC-induced degradation of cilastatin in natural water and treated wastewater. CHEMOSPHERE 2021; 280:130668. [PMID: 33962299 DOI: 10.1016/j.chemosphere.2021.130668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/20/2021] [Accepted: 04/23/2021] [Indexed: 06/12/2023]
Abstract
This work reports for the first time the UVC photodegradation of cilastatin, a renal dehydropeptidase inhibitor co-adminstered with the imipenem antibiotic. Initially, solutions of cilastatin at varying concentrations were prepared in ultra-pure water and the direct photolysis of cilastatin was monitored under 254-nm irradiation. Degradation was slower at higher initial cilastatin concentrations, due to absorption saturation. Of the different eluting photoproducts, only one was tentatively identified as oxidized cilastatin bearing a sulfoxide group. UV-254 photolysis occurred faster at lower pH values, because the protonated forms of the molecule (H3A+, H2A) have both higher absorption coefficients and higher photolysis quantum yields than the non-protonated ones (HA-, A2-). The direct photolysis of cilastatin does not involve •OH, as excluded by experiments in which t-butanol was added as •OH scavenger, whereas the presence of humic acids inhibited photolysis due to competition for radiation absorption. The same explanation partially accounts for the observation that the photolysis kinetics of cilastatin was slower in tap water, river water and treated wastewater samples compared to ultra-pure water. Moreover, the direct photolysis quantum yield was also lower in water matrices compared to ultra-pure water. Similar findings reported for triclosan and the herbicide 2-methyl-4-chlorophenoxyacetic acid in previous studies might suggest that the water matrix components could carry out either physical quenching of cilastatin's excited states or back-reduction to cilastatin of the partially oxidized degradation intermediates. Overall, the present results demonstrate that UVC irradiation is a fast and efficient process for the degradation of cilastatin in natural water and treated wastewater.
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Affiliation(s)
- Nicoleta Solomou
- Laboratory of Aquatic Chemistry, School of Environmental Engineering, Technical University of Crete, GR-73100, Chania, Crete, Greece
| | - Marco Minella
- Department of Chemistry, University of Torino, Via P. Giuria 5, 10125, Torino, Italy
| | - Davide Vione
- Department of Chemistry, University of Torino, Via P. Giuria 5, 10125, Torino, Italy.
| | - Elefteria Psillakis
- Laboratory of Aquatic Chemistry, School of Environmental Engineering, Technical University of Crete, GR-73100, Chania, Crete, Greece.
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Carena L, Fabbri D, Passananti M, Minella M, Pazzi M, Vione D. The role of direct photolysis in the photodegradation of the herbicide bentazone in natural surface waters. CHEMOSPHERE 2020; 246:125705. [PMID: 31891848 DOI: 10.1016/j.chemosphere.2019.125705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 12/14/2019] [Accepted: 12/17/2019] [Indexed: 06/10/2023]
Abstract
The photochemical fate of the herbicide bentazone was assessed by lab experiments and modeling tools. Experimental and modeling results showed that bentazone is mainly photodegraded by direct photolysis in natural water samples, even in the presence of dissolved organic matter (DOM) that can act as light-screening agent, photosensitizer and scavenger of reactive species. Even when it was dissolved in natural water samples containing different DOM amounts, the phototransformation kinetics of bentazone was unchanged compared to irradiation runs in ultrapure water. This finding suggests that the DOM and the other components of our samples did not affect the direct photolysis of bentazone by light-absorption competition, at least at the experimental optical path lengths, and did not induce significant indirect photodegradation by producing reactive transient species. Photochemical modeling in a lake-water photoreactivity scenario corroborated the observed experimental results, showing the predominant role of direct photolysis in the overall (direct + indirect) photodegradation of bentazone at different water depths and DOM contents. However, the model predicted a minor but non-negligible contribution of indirect photochemistry (i.e., reactions triggered by HO•, CO3•- and 3CDOM*) to the herbicide degradation. This contribution (especially by 3CDOM*) could become crucial in deep and DOM-rich water bodies. Finally, several photoproducts formed by direct photolysis and HO•-induced photodegradation were identified, which should not be particularly toxic for aquatic organisms and Vibrio fischeri bacteria.
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Affiliation(s)
- Luca Carena
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy.
| | - Debora Fabbri
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy
| | - Monica Passananti
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy
| | - Marco Minella
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy
| | - Marco Pazzi
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy
| | - Davide Vione
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy
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A Critical View of the Application of the APEX Software (Aqueous Photochemistry of Environmentally-Occurring Xenobiotics) to Predict Photoreaction Kinetics in Surface Freshwaters. Molecules 2019; 25:molecules25010009. [PMID: 31861417 PMCID: PMC7017383 DOI: 10.3390/molecules25010009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 12/09/2019] [Accepted: 12/11/2019] [Indexed: 02/01/2023] Open
Abstract
The APEX (aqueous photochemistry of environmentally occurring xenobiotics) software computes the phototransformation kinetics of compounds that occur in sunlit surface waters. It is free software based on Octave, and was originally released in 2014. Since then, APEX has proven to be a remarkably flexible platform, allowing for the addressing of several environmental problems. However, considering APEX as a stand-alone software is not conducive to exploiting its full potentialities. Rather, it is part of a whole ecosystem that encompasses both the software and the laboratory protocols that allow for the measurement of substrate photoreactivity parameters. Coherently with this viewpoint, the present paper shows both how to use APEX, and how to experimentally derive or approximately assess the needed input data. Attention is also given to some issues that might provide obstacles to users, including the extension of APEX beyond the simple systems for which it was initially conceived. In particular, we show how to use APEX to deal with compounds that undergo acid–base equilibria, and with the photochemistry of systems such as stratified lakes, lakes undergoing evaporation, and rivers. Hopefully, this work will provide a reference for the smooth use of one of the most powerful instruments for the modeling of photochemical processes in freshwater environments. All authors have read and agreed to the published version of the manuscript.
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Cyrille NN, Idrice AA, Maraf MB, Charles FA, Ibrahim MN, Ríos‐Gutierrez M, Domingo LR. Understanding the Mechanism of Nitrobenzene Nitration with Nitronium Ion: A Molecular Electron Density Theory Study. ChemistrySelect 2019. [DOI: 10.1002/slct.201903699] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Nana Nouhou Cyrille
- Physical and Theoretical Chemistry LaboratoryFaculty of Science, University of Yaoundé I P.O. Box 812 Yaoundé Cameroon
- Computational Chemistry LaboratoryHigh Teacher Training CollegeUniversity of Yaoundé I P. O. Box 47 Yaoundé Cameroon
| | - Adjieufack Abel Idrice
- Physical and Theoretical Chemistry LaboratoryFaculty of Science, University of Yaoundé I P.O. Box 812 Yaoundé Cameroon
- Computational Chemistry LaboratoryHigh Teacher Training CollegeUniversity of Yaoundé I P. O. Box 47 Yaoundé Cameroon
| | - Mbah Bake Maraf
- Physical and Theoretical Chemistry LaboratoryFaculty of Science, University of Yaoundé I P.O. Box 812 Yaoundé Cameroon
- Computational Chemistry LaboratoryHigh Teacher Training CollegeUniversity of Yaoundé I P. O. Box 47 Yaoundé Cameroon
| | - Fon Abi Charles
- Computational Chemistry LaboratoryHigh Teacher Training CollegeUniversity of Yaoundé I P. O. Box 47 Yaoundé Cameroon
| | - Mbouombouo Ndassa Ibrahim
- Computational Chemistry LaboratoryHigh Teacher Training CollegeUniversity of Yaoundé I P. O. Box 47 Yaoundé Cameroon
| | - Mar Ríos‐Gutierrez
- Department of Organic ChemistryUniversity of Valencia Dr. Moliner 50, Burjassot Valencia 46100 Spain
- Department of Chemistry and Chemical BiologyMcMaster University 1280 Main Street West, Hamilton Ontario L8 S 4 L8 Canada
| | - Luis Ramon Domingo
- Department of Organic ChemistryUniversity of Valencia Dr. Moliner 50, Burjassot Valencia 46100 Spain
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Carena L, Puscasu CG, Comis S, Sarakha M, Vione D. Environmental photodegradation of emerging contaminants: A re-examination of the importance of triplet-sensitised processes, based on the use of 4-carboxybenzophenone as proxy for the chromophoric dissolved organic matter. CHEMOSPHERE 2019; 237:124476. [PMID: 31404736 DOI: 10.1016/j.chemosphere.2019.124476] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/24/2019] [Accepted: 07/27/2019] [Indexed: 06/10/2023]
Abstract
The photoreactions sensitised by the excited triplet states of chromophoric dissolved organic matter (3CDOM*) are very important in the photochemical attenuation of emerging contaminants in natural waters. Until quite recently, anthraquinone-2-sulphonate (AQ2S) was the only available CDOM proxy molecule to estimate the contaminant reaction kinetics with 3CDOM*, under steady-state irradiation conditions. Unfortunately, the AQ2S triplet state (3AQ2S*) is considerably more reactive than average 3CDOM*. We have recently developed an alternative protocol based on 4-carboxybenzophenone (CBBP), the triplet state of which (3CBBP*) is less reactive compared to 3AQ2S*. Here we show that in the case of ibuprofen (IBP), paracetamol (APAP) and clofibric acid (CLO), the reaction rate constants with 3CBBP* are more reasonable as 3CDOM* reactivity estimates than those obtained by using AQ2S. In contrast, similar rate constants are measured for the reaction of atrazine (ATZ) with either 3AQ2S* or 3CBBP*. Moreover, the reactivity of ATZ with both 3AQ2S* and 3CBBP* is very similar to that with 3CDOM*, available through a literature estimate. The possibility to validate the ATZ-3CBBP* reactivity estimate against the 3CDOM* data, and to accurately predict the reported IBP and CLO field lifetime, support the suitability of CBBP as CDOM proxy. The replacement of AQ2S with CBBP as proxy molecule does not reverse the qualitative prediction, according to which 3CDOM* would be the main process involved in the photodegradation of the studied contaminants in waters with high dissolved organic carbon (DOC). However, the CBBP-based data prompt for an important reconsideration of the estimated lifetimes at high DOC.
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Affiliation(s)
- Luca Carena
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy
| | - Cezara G Puscasu
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy
| | - Silvia Comis
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy
| | - Mohamed Sarakha
- Institut de Chimie de Clermont-Ferrand, Clermont Université, Université Blaise Pascal, F-63177, Aubière, France
| | - Davide Vione
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125, Torino, Italy.
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Serna-Galvis EA, Troyon JA, Giannakis S, Torres-Palma RA, Carena L, Vione D, Pulgarin C. Kinetic modeling of lag times during photo-induced inactivation of E. coli in sunlit surface waters: Unraveling the pathways of exogenous action. WATER RESEARCH 2019; 163:114894. [PMID: 31374404 DOI: 10.1016/j.watres.2019.114894] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/18/2019] [Accepted: 07/21/2019] [Indexed: 05/25/2023]
Abstract
This work presents a kinetic analysis of the exogenous photo-induced disinfection of E. coli in natural waters. Herein, the inactivation of bacteria by light and photo-generated transient species, i.e., hydroxyl radical (HO•), excited triplet states of organic matter (3CDOM*) and singlet oxygen (1O2), was studied. It was found that the exogenous disinfection of E. coli proceeds through a lag time, followed by an exponential phase triggered by photo-generated HO•, 1O2 and 3CDOM*. Also, we report that the concentration increased of transient species (and especially HO•) precursors decreased the lag times of bacteria inactivation. Due to the limitations of the competition kinetics methodology to include the lag phase, an alternative strategy to study the interaction between E. coli and photo-generated transient species was proposed, considering the log-linear pseudo-first order rate constants and lag-times. On this basis and by using APEX software, a full kinetic analysis of exogenous bacterial inactivation, taking into account both lag-time and exponential decay, was developed. This approach provided insights into the conditions that could make exogenous inactivation competitive with the endogenous process for the E. coli inactivation in natural sunlit waters. Hence, this research contributes to the understanding of fundamental kinetic aspects of photoinduced bacterial inactivation, which is the basis for light-assisted processes such as the solar disinfection (SODIS).
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Affiliation(s)
- Efraim A Serna-Galvis
- School of Basic Sciences (SB), Institute of Chemical Science and Engineering (ISIC), Group of Advanced Oxidation Processes (GPAO), École Polytechnique Fédérale de Lausanne (EPFL), Station 6, CH-1015, Lausanne, Switzerland; Grupo de Investigación en Remediación Ambiental y Biocatálisis (GIRAB), Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquía UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - Jean Arnaud Troyon
- School of Basic Sciences (SB), Institute of Chemical Science and Engineering (ISIC), Group of Advanced Oxidation Processes (GPAO), École Polytechnique Fédérale de Lausanne (EPFL), Station 6, CH-1015, Lausanne, Switzerland
| | - Stefanos Giannakis
- School of Basic Sciences (SB), Institute of Chemical Science and Engineering (ISIC), Group of Advanced Oxidation Processes (GPAO), École Polytechnique Fédérale de Lausanne (EPFL), Station 6, CH-1015, Lausanne, Switzerland; Universidad Politécnica de Madrid, E.T.S. Ingenieros de Caminos, Canales y Puertos, Departamento de Hidráulica, Energía y Medio Ambiente, Unidad docente Ingeniería Sanitaria c/Profesor Aranguren, s/n, ES-28040, Madrid, Spain
| | - Ricardo A Torres-Palma
- Grupo de Investigación en Remediación Ambiental y Biocatálisis (GIRAB), Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquía UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - Luca Carena
- Dipartimento di Chimica, Università di Torino, Via P. Giuria 5, 10125, Torino, Italy
| | - Davide Vione
- Dipartimento di Chimica, Università di Torino, Via P. Giuria 5, 10125, Torino, Italy.
| | - Cesar Pulgarin
- School of Basic Sciences (SB), Institute of Chemical Science and Engineering (ISIC), Group of Advanced Oxidation Processes (GPAO), École Polytechnique Fédérale de Lausanne (EPFL), Station 6, CH-1015, Lausanne, Switzerland.
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Vione D, Scozzaro A. Photochemistry of Surface Fresh Waters in the Framework of Climate Change. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:7945-7963. [PMID: 31241909 DOI: 10.1021/acs.est.9b00968] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Photochemical processes taking place in surface fresh waters play an important role in the transformation of biorecalcitrant pollutants and some natural compounds and in the inactivation of microorganisms. Such processes are divided into direct photolysis, where a molecule is transformed following sunlight absorption, and indirect photochemistry, where naturally occurring photosensitizers absorb sunlight and produce a range of transient species that can transform dissolved molecules (or inactivate microorganisms). Photochemistry is usually favored in thoroughly illuminated shallow waters, while the dissolved organic carbon (DOC) acts as a switch between different photochemical pathways (direct photolysis, and indirect photochemistry triggered by different transient species). Various phenomena connected with climate change (water browning, changing precipitations) may affect water DOC and water depth, with implications for the kinetics of photoreactions and the associated transformation pathways. The latter are important because they often produce peculiar intermediates, with particular health and environmental impacts. Further climate-induced effects with photochemical implications are shorter ice-cover seasons and enhanced duration of summer stratification in lakes, as well as changes in the flow velocity of rivers that affect the photodegradation time scale. This contribution aims at showing how the different climate-related phenomena can affect photoreactions and which approaches can be followed to quantitatively describe these variations.
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Affiliation(s)
- Davide Vione
- Department of Chemistry , University of Torino , Via P. Giuria 5 , 10125 Torino , Italy
| | - Andrea Scozzaro
- Department of Chemistry , University of Torino , Via P. Giuria 5 , 10125 Torino , Italy
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Lastre-Acosta AM, Barberato B, Parizi MPS, Teixeira ACSC. Direct and indirect photolysis of the antibiotic enoxacin: kinetics of oxidation by reactive photo-induced species and simulations. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:4337-4347. [PMID: 29931641 DOI: 10.1007/s11356-018-2555-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 06/13/2018] [Indexed: 06/08/2023]
Abstract
The purpose of this study was to investigate the aqueous phase photochemical behavior of enoxacin (ENO), an antibiotic selected as a model pollutant of emerging concern. The second-order reaction rate constants of ENO with hydroxyl radicals (HO●) and singlet oxygen (1O2) were determined at pH 3, 7, and 9. Also, the rate constants of the electron transfer reaction between ENO and triplet states of chromophoric dissolved organic matter (3CDOM*) are reported for the first time, based on anthraquinone-2-sulfonate (AQ2S) as CDOM proxy. The sunlight-driven direct and indirect ENO degradation in the presence of dissolved organic matter (DOM) is also discussed. The results show that direct photolysis, which occurs more rapidly at higher pH, along with the reactions with HO● and 3AQ2S*, is the key pathway involved in ENO degradation. The ENO zwitterions, prevailing at pH 7, show kENO, HO●, kENO,1O2, and kENO,3AQ2S* of (14.0 ± 0.8) × 1010, (3.9 ± 0.2) × 106, and (61.5 ± 0.7) × 108 L mol-1 s-1, respectively, whose differences at pH 3, 7, and 9 are due to ENO pH-dependent speciation and reactivity. These k values, along with the experimental ENO photolysis quantum yield, were used in mathematical simulations for predicting ENO persistence in sunlit natural waters. According to the simulations, dissolved organic matter and water depth are expected to have the highest impacts on ENO half-life, varying from a few hours to days in summertime, depending on the concentrations of relevant waterborne species (organic matter, NO3-, NO2-, HCO3-).
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Affiliation(s)
- Arlen Mabel Lastre-Acosta
- Research Group in Advanced Oxidation Processes (AdOx), Chemical Systems Engineering Center, Department of Chemical Engineering, University of São Paulo, Av. Prof. Luciano Gualberto, tr. 3, São Paulo, SP, 380, Brazil.
| | - Bruna Barberato
- Research Group in Advanced Oxidation Processes (AdOx), Chemical Systems Engineering Center, Department of Chemical Engineering, University of São Paulo, Av. Prof. Luciano Gualberto, tr. 3, São Paulo, SP, 380, Brazil
| | - Marcela Prado Silva Parizi
- Department of Energy Engineering, São Paulo State University (UNESP), Av. Barrageiros, Rosana, SP, 1881, Brazil.
| | - Antonio Carlos Silva Costa Teixeira
- Research Group in Advanced Oxidation Processes (AdOx), Chemical Systems Engineering Center, Department of Chemical Engineering, University of São Paulo, Av. Prof. Luciano Gualberto, tr. 3, São Paulo, SP, 380, Brazil
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Berto S, Carena L, Chiavazza E, Marletti M, Fin A, Giacomino A, Malandrino M, Barolo C, Prenesti E, Vione D. Off-line and real-time monitoring of acetaminophen photodegradation by an electrochemical sensor. CHEMOSPHERE 2018; 204:556-562. [PMID: 29602587 DOI: 10.1016/j.chemosphere.2018.03.069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/09/2018] [Accepted: 03/10/2018] [Indexed: 06/08/2023]
Abstract
The photochemistry of N-acetyl-para-aminophenol (acetaminophen, APAP) is here investigated by using differential pulse voltammetry (DPV) analysis to monitor APAP photodegradation upon steady-state irradiation. The purpose of this work is to assess the applicability of DPV to monitor the photochemical behaviour of xenobiotics, along with the development of an electrochemical set-up for the real-time monitoring of APAP photodegradation. We here investigated the APAP photoreactivity towards the main photogenerated reactive transients species occurring in sunlit surface waters (hydroxyl radical HO, carbonate radical CO3-, excited triplet state of anthraquinone-2-sulfonate used as proxy of the chromophoric DOM, and singlet oxygen 1O2), and determined relevant kinetic parameters. A standard procedure based on UV detection coupled with liquid chromatography (HPLC-UV) was used under identical experimental conditions to compare and verify the DPV-based results. The latter were in agreement with HPLC data, with the exception of the triplet-sensitized processes. In the other cases, DPV could be used as an alternative to the well-tested but more costly and time-consuming HPLC-UV technique. We have also assessed the reaction rate constant between APAP and HO by real-time DPV, which allowed for the monitoring of APAP photodegradation inside the irradiation chamber. Unfortunately, real-time DPV measurements are likely to be affected by temperature variations of the irradiated samples. Overall, DPV appeared as a fast, cheap and reasonably reliable technique when used for the off-line monitoring of APAP photodegradation. When a suitable real-time procedure is developed, it could become a very straightforward method to study the photochemical behaviour of electroactive xenobiotics.
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Affiliation(s)
- Silvia Berto
- Dept. of Chemistry, University of Torino, Via P. Giuria 7, 10125 Turin, Italy.
| | - Luca Carena
- Dept. of Chemistry, University of Torino, Via P. Giuria 7, 10125 Turin, Italy.
| | - Enrico Chiavazza
- Dept. of Chemistry, University of Torino, Via P. Giuria 7, 10125 Turin, Italy
| | - Matteo Marletti
- Dept. of Chemistry, University of Torino, Via P. Giuria 7, 10125 Turin, Italy
| | - Andrea Fin
- Dept. of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0358, United States
| | - Agnese Giacomino
- Dept. of Drug Science and Technology, University of Torino, Via P. Giuria 9, 10125 Turin, Italy
| | - Mery Malandrino
- Dept. of Chemistry, University of Torino, Via P. Giuria 7, 10125 Turin, Italy
| | - Claudia Barolo
- Dept. of Chemistry, University of Torino, Via P. Giuria 7, 10125 Turin, Italy; INSTM and NIS Centre, University of Torino, Via Quarello 15A, 10135 Turin, Italy
| | - Enrico Prenesti
- Dept. of Chemistry, University of Torino, Via P. Giuria 7, 10125 Turin, Italy
| | - Davide Vione
- Dept. of Chemistry, University of Torino, Via P. Giuria 7, 10125 Turin, Italy
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Minella M, Rapa L, Carena L, Pazzi M, Maurino V, Minero C, Brigante M, Vione D. An experimental methodology to measure the reaction rate constants of processes sensitised by the triplet state of 4-carboxybenzophenone as a proxy of the triplet states of chromophoric dissolved organic matter, under steady-state irradiation conditions. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2018; 20:1007-1019. [PMID: 29876570 DOI: 10.1039/c8em00155c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
By a combination of transient absorption spectroscopy and steady-state irradiation experiments, we investigated the transformation of phenol and furfuryl alcohol (FFA) sensitised by irradiated 4-carboxybenzophenone (CBBP). The latter is a reasonable proxy molecule to assess the reactivity of the excited triplet states of the chromophoric dissolved organic matter that occurs in natural waters. The main reactive species for the transformation of both phenol and FFA was the CBBP triplet state, despite the fact that FFA is a commonly used probe for 1O2. In the case of FFA it was possible to develop a simple kinetic model that fitted well the experimental data obtained by steady-state irradiation, in a wide range of FFA concentration values. In the case of phenol the model was made much more complex by the likely occurrence of back reactions between radical species (e.g., phenoxyl and superoxide). This problem can be tackled by considering only the experimental data at low phenol concentration, where the degradation rate increases linearly with concentration. We do not recommend the use of 1O2 scavengers/quenchers such as sodium azide to elucidate CBBP photoreaction pathways, because the azide provides misleading results by also acting as a triplet-state quencher. Based on the experimental data, we propose a methodology for the measurement of the CBBP triplet-sensitisation rate constants from steady-state irradiation experiments, allowing for a better assessment of the triplet-sensitised degradation of emerging contaminants.
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Affiliation(s)
- Marco Minella
- Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125 Torino, Italy.
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Chemical Quenching of Singlet Oxygen and Other Reactive Oxygen Species in Water: A Reliable Method for the Determination of Quantum Yields in Photochemical Processes? CHEMPHOTOCHEM 2018. [DOI: 10.1002/cptc.201800038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Minella M, Giannakis S, Mazzavillani A, Maurino V, Minero C, Vione D. Phototransformation of Acesulfame K in surface waters: Comparison of two techniques for the measurement of the second-order rate constants of indirect photodegradation, and modelling of photoreaction kinetics. CHEMOSPHERE 2017; 186:185-192. [PMID: 28778016 DOI: 10.1016/j.chemosphere.2017.07.128] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 07/18/2017] [Accepted: 07/25/2017] [Indexed: 06/07/2023]
Abstract
By use of photochemical modelling we show that acesulfame K (ACE) can undergo photodegradation in surface waters, mainly by reaction with OH and possibly 3CDOM* (the triplet states of chromophoric dissolved organic matter). With the possible exception of shallow water bodies containing low dissolved organic carbon, we predict ACE to be a refractory compound in environmental waters which agrees well with many literature reports. We used two methods to measure the photoreactivity parameters of ACE, of which one is based on the monitoring of the time evolution of ACE alone and the other is based on the monitoring of both ACE and a reference compound (hereafter, they are referred to as substrate-only and substrate + reference method, respectively). The substrate + reference method can be time-saving, but it is potentially prone to interferences. In this work, ibuprofen and atrazine were used as reference compounds of known behaviour to study the photoreactivity of ACE by competition kinetics in the substrate + reference method. The two methods gave overall comparable results, partially because two different reference compounds instead of only one were used in the substrate + reference method. By so doing, however, one loses part of the time-saving advantage of the substrate + reference method.
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Affiliation(s)
- Marco Minella
- Dipartimento di Chimica, Università di Torino, Via P. Giuria 5, 10125, Torino, Italy
| | - Stefanos Giannakis
- SB, ISIC, Group of Advanced Oxidation Processes (GPAO), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Alice Mazzavillani
- Dipartimento di Chimica, Università di Torino, Via P. Giuria 5, 10125, Torino, Italy
| | - Valter Maurino
- Dipartimento di Chimica, Università di Torino, Via P. Giuria 5, 10125, Torino, Italy
| | - Claudio Minero
- Dipartimento di Chimica, Università di Torino, Via P. Giuria 5, 10125, Torino, Italy
| | - Davide Vione
- Dipartimento di Chimica, Università di Torino, Via P. Giuria 5, 10125, Torino, Italy.
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Calza P, Noè G, Fabbri D, Santoro V, Minero C, Vione D, Medana C. Photoinduced transformation of pyridinium-based ionic liquids, and implications for their photochemical behavior in surface waters. WATER RESEARCH 2017; 122:194-206. [PMID: 28601032 DOI: 10.1016/j.watres.2017.05.064] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 05/26/2017] [Accepted: 05/28/2017] [Indexed: 06/07/2023]
Abstract
The photochemical reactivity of three ionic liquids (1-ethylpyridinium tetrafluoroborate, 1-butyl-4-methylpyridinium tetrafluoroborate, and 1-(3-cyanopropyl)pyridinium chloride) was studied by combining laboratory experiments and photochemical modeling, to get insight into the possible behavior in surface-water environments. Among the studied compounds, phototransformation in sunlit surface waters could be an important attenuation pathway for 1-butyl-4-methylpyridinium tetrafluoroborate (BMPOTFB). In this case the reaction with the carbonate radicals (CO3-) would prevail at low values of the dissolved organic carbon (DOC), while the direct photolysis would be important at intermediate to high DOC values. The sensitization by the triplet states of chromophoric dissolved organic matter could play a significant role at high DOC, especially in the presence of a considerable fraction of highly photoreactive pedogenic organic matter derived from soil runoff. The main processes that account for the phototransformation of BMPOTFB and produce the main detected transformation products (TPs) are hydroxylation, detachment/shortening of the butyl chain and double bond formation. Interestingly, there is a considerable overlap between the TPs formed by direct photolysis and those produced by indirect photochemistry. Some of the TPs formed from BMPOTFB are more toxic than the parent compound towards Vibrio fischeri bacteria, and account for the increase in toxicity of the irradiated mixtures. Differently from BMPOTFB, in the case of the other two studied ionic liquids the photodegradation would play a negligible role in environmental attenuation, with the possible exception of very shallow waters with low DOC.
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Affiliation(s)
- Paola Calza
- Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy
| | - Giorgio Noè
- Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy
| | - Debora Fabbri
- Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy
| | - Valentina Santoro
- Department of Molecular Biotechnology and Health Sciences, University of Torino, via P. Giuria 5, 10125 Torino, Italy
| | - Claudio Minero
- Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy
| | - Davide Vione
- Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy.
| | - Claudio Medana
- Department of Molecular Biotechnology and Health Sciences, University of Torino, via P. Giuria 5, 10125 Torino, Italy
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Carena L, Minella M, Barsotti F, Brigante M, Milan M, Ferrero A, Berto S, Minero C, Vione D. Phototransformation of the Herbicide Propanil in Paddy Field Water. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:2695-2704. [PMID: 28145687 DOI: 10.1021/acs.est.6b05053] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
When irradiated in paddy-field water, propanil (PRP) undergoes photodegradation by direct photolysis, by reactions with •OH and CO3•-, and possibly also with the triplet states of chromophoric dissolved organic matter. Irradiation also inhibits the nonphotochemical (probably biological) degradation of PRP. The dark- and light-induced pathways can be easily distinguished because 3,4-dichloroaniline (34DCA, a transformation intermediate of considerable environmental concern) is produced with almost 100% yield in the dark but not at all through photochemical pathways. This issue allows an easy assessment of the dark process(es) under irradiation. In the natural environment, we expect PRP photodegradation to be important only in the presence of elevated nitrate and/or nitrite levels, e.g., [NO3-] approaching 1 mmol L-1 (corresponding to approximately 60 mg L-1). Under these circumstances, •OH and CO3•- would play a major role in PRP phototransformation. Because flooded paddy fields are efficient denitrification bioreactors that can achieve decontamination of nitrate-rich water used for irrigation, irrigation with such water would both enhance PRP photodegradation and divert PRP dissipation processes away from the production of 34DCA, at least in the daylight hours.
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Affiliation(s)
- Luca Carena
- Dipartimento di Chimica, Università di Torino , Via Pietro Giuria 5, 10125 Torino, Italy
| | - Marco Minella
- Dipartimento di Chimica, Università di Torino , Via Pietro Giuria 5, 10125 Torino, Italy
| | - Francesco Barsotti
- Dipartimento di Chimica, Università di Torino , Via Pietro Giuria 5, 10125 Torino, Italy
| | - Marcello Brigante
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, & CNRS, UMR 6296, ICCF, BP 80026 , F-63177 Aubière, France
| | - Marco Milan
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università di Torino , Largo Paolo Braccini 2, 10095 Grugliasco (TO), ITALY
| | - Aldo Ferrero
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università di Torino , Largo Paolo Braccini 2, 10095 Grugliasco (TO), ITALY
| | - Silvia Berto
- Dipartimento di Chimica, Università di Torino , Via Pietro Giuria 5, 10125 Torino, Italy
| | - Claudio Minero
- Dipartimento di Chimica, Università di Torino , Via Pietro Giuria 5, 10125 Torino, Italy
| | - Davide Vione
- Dipartimento di Chimica, Università di Torino , Via Pietro Giuria 5, 10125 Torino, Italy
- Università di Torino , Centro Interdipartimentale NatRisk, Largo Paolo Braccini 2, 10095 Grugliasco (TO), Italy
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Avetta P, Fabbri D, Minella M, Brigante M, Maurino V, Minero C, Pazzi M, Vione D. Assessing the phototransformation of diclofenac, clofibric acid and naproxen in surface waters: Model predictions and comparison with field data. WATER RESEARCH 2016; 105:383-394. [PMID: 27657658 DOI: 10.1016/j.watres.2016.08.058] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 08/24/2016] [Accepted: 08/27/2016] [Indexed: 05/27/2023]
Abstract
Phototransformation is important for the fate in surface waters of the pharmaceuticals diclofenac (DIC) and naproxen (NAP) and for clofibric acid (CLO), a metabolite of the drug clofibrate. The goal of this paper is to provide an overview of the prevailing photochemical processes, which these compounds undergo in the different conditions found in freshwater environments. The modelled photochemical half-life times of NAP and DIC range from a few days to some months, depending on water conditions (chemistry and depth) and on the season. The model indicates that direct photolysis is the dominant degradation pathway of DIC and NAP in sunlit surface waters, and potentially toxic cyclic amides were detected as intermediates of DIC direct phototransformation. With modelled half-life times in the month-year range, CLO is predicted to be more photostable than DIC or NAP and to be degraded mainly by reaction with the •OH radical and with the triplet states of chromophoric dissolved organic matter (3CDOM*). The CLO intermediates arising from these processes and detected in this study (hydroquinone and 4-chlorophenol) are, respectively, a chronic toxicant to aquatic organisms and a possible carcinogen for humans. Hydroquinone is formed with only ∼5% yield upon CLO triplet-sensitised transformation, but it is highly toxic for algae and crustaceans. In contrast, the formation yield of 4-chlorophenol reaches ∼50% upon triplet sensitisation and ∼10% by ·OH reaction. The comparison of model predictions with field data from a previous study yielded a very good agreement in the case of DIC and, when using 4-carboxybenzophenone as proxy for triplet sensitisation by CDOM, a good agreement was found for CLO as well. In the case of NAP, the comparison with field data suggests that its direct photolysis quantum yield approaches or even falls below the lower range of literature values.
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Affiliation(s)
- Paola Avetta
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy(1)
| | - Debora Fabbri
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy(1)
| | - Marco Minella
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy(1)
| | - Marcello Brigante
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, BP 80026, F-63177 Aubière, France
| | - Valter Maurino
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy(1)
| | - Claudio Minero
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy(1)
| | - Marco Pazzi
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy(1)
| | - Davide Vione
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy(1); Università degli Studi di Torino, Centro Interdipartimentale NatRisk, Via L. Da Vinci 44, 10095 Grugliasco (TO), Italy(2).
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20
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Bianco A, Fabbri D, Minella M, Brigante M, Mailhot G, Maurino V, Minero C, Vione D. Photochemical transformation of benzotriazole, relevant to sunlit surface waters: Assessing the possible role of triplet-sensitised processes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 566-567:712-721. [PMID: 27239714 DOI: 10.1016/j.scitotenv.2016.05.119] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/22/2016] [Accepted: 05/17/2016] [Indexed: 06/05/2023]
Affiliation(s)
- Angelica Bianco
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand, France
| | - Debora Fabbri
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Turin, Italy(1)
| | - Marco Minella
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Turin, Italy(1)
| | - Marcello Brigante
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, BP 80026, F-63177 Aubière, France.
| | - Gilles Mailhot
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, BP 80026, F-63177 Aubière, France
| | - Valter Maurino
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Turin, Italy(1)
| | - Claudio Minero
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Turin, Italy(1)
| | - Davide Vione
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Turin, Italy(1); Università degli Studi di Torino, Centro Interdipartimentale NatRisk, Via L. Da Vinci 44, 10095 Grugliasco (TO), Italy(2).
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Zhu GL, Zhang LW, Liu YC, Cui ZF, Xu XS, Wu GZ. Laser Flash Photolysis Mechanism of Anthraquinone-2-Sodium Sulfonate in Pyridine Ionic Liquid/Water Mixed System. CHINESE J CHEM PHYS 2016. [DOI: 10.1063/1674-0068/29/cjcp1509192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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22
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Vione D, Calza P, Galli F, Fabbri D, Santoro V, Medana C. The role of direct photolysis and indirect photochemistry in the environmental fate of ethylhexyl methoxy cinnamate (EHMC) in surface waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 537:58-68. [PMID: 26282740 DOI: 10.1016/j.scitotenv.2015.08.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 07/31/2015] [Accepted: 08/01/2015] [Indexed: 05/28/2023]
Abstract
The aquatic environmental fate of ethylhexyl methoxy cinnamate (EHMC), one of the most used UVB filters worldwide, was studied by assessing its environmental persistence and photoinduced transformations. The role of direct and indirect photolysis was evaluated. Direct photolysis was shown to play a key role, and this process is expected to be the main attenuation route of EHMC in sunlit surface waters. In contrast, the reaction with OH radicals would be negligible and that with (3)CDOM* would at most be a secondary process. The measurement of the quantum yield of direct photolysis and of the rate constants of reaction with photogenerated transient species (or, sometimes, the use of reasonable values for the latter) allowed the prediction of the EHMC half-life time in surface waters, by means of a validated photochemical model. The predicted EHMC lifetime is of the order of hours to a few days in fair-weather summertime, and the main factors controlling the EHMC phototransformation in sunlit surface waters would be the water depth and the dissolved organic carbon (DOC) content. The formation of transformation products (TPs) was followed as well via HPLC/HRMS. Three TPs were detected in the samples exposed to UVA radiation, while one additional TP was detected in the samples exposed to UVB radiation. The detected TPs comprised 4-methoxybenzaldehyde, a hydroxylated derivative and dimeric species. Through the use of heterogeneous photocatalysis with TiO2, seven additional TPs were identified, most of them resulting from the further degradation of primary TPs formed through direct photolysis and that might be detected in aquatic systems as well. The photodegradation of EHMC in the presence of TiO2 yielded more toxic TPs than the parent compound (as determined with the Vibrio fischeri Microtox assay). The increased toxicity is partially accounted for by the formation of 4-methoxybenzaldehyde.
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Affiliation(s)
- D Vione
- Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy
| | - P Calza
- Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy.
| | - F Galli
- Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy
| | - D Fabbri
- Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy
| | - V Santoro
- Department of Molecular Biotechnology and Health Sciences, University of Torino, via P. Giuria 5, 10125 Torino, Italy
| | - C Medana
- Department of Molecular Biotechnology and Health Sciences, University of Torino, via P. Giuria 5, 10125 Torino, Italy
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Prasse C, Wenk J, Jasper JT, Ternes TA, Sedlak DL. Co-occurrence of Photochemical and Microbiological Transformation Processes in Open-Water Unit Process Wetlands. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:14136-45. [PMID: 26562588 DOI: 10.1021/acs.est.5b03783] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The fate of anthropogenic trace organic contaminants in surface waters can be complex due to the occurrence of multiple parallel and consecutive transformation processes. In this study, the removal of five antiviral drugs (abacavir, acyclovir, emtricitabine, lamivudine and zidovudine) via both bio- and phototransformation processes, was investigated in laboratory microcosm experiments simulating an open-water unit process wetland receiving municipal wastewater effluent. Phototransformation was the main removal mechanism for abacavir, zidovudine, and emtricitabine, with half-lives (t1/2,photo) in wetland water of 1.6, 7.6, and 25 h, respectively. In contrast, removal of acyclovir and lamivudine was mainly attributable to slower microbial processes (t1/2,bio = 74 and 120 h, respectively). Identification of transformation products revealed that bio- and phototransformation reactions took place at different moieties. For abacavir and zidovudine, rapid transformation was attributable to high reactivity of the cyclopropylamine and azido moieties, respectively. Despite substantial differences in kinetics of different antiviral drugs, biotransformation reactions mainly involved oxidation of hydroxyl groups to the corresponding carboxylic acids. Phototransformation rates of parent antiviral drugs and their biotransformation products were similar, indicating that prior exposure to microorganisms (e.g., in a wastewater treatment plant or a vegetated wetland) would not affect the rate of transformation of the part of the molecule susceptible to phototransformation. However, phototransformation strongly affected the rates of biotransformation of the hydroxyl groups, which in some cases resulted in greater persistence of phototransformation products.
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Affiliation(s)
- Carsten Prasse
- ReNUWIt Engineering Research Center and Department of Civil & Environmental Engineering, University of California at Berkeley , Berkeley, California 94720, United States
- Department of Aquatic Chemistry, Federal Institute of Hydrology , D-56002 Koblenz, Germany
| | - Jannis Wenk
- ReNUWIt Engineering Research Center and Department of Civil & Environmental Engineering, University of California at Berkeley , Berkeley, California 94720, United States
- Department of Chemical Engineering and Water Innovation & Research Centre, University of Bath , Claverton Down, Bath BA2 7AY, United Kingdom
| | - Justin T Jasper
- ReNUWIt Engineering Research Center and Department of Civil & Environmental Engineering, University of California at Berkeley , Berkeley, California 94720, United States
| | - Thomas A Ternes
- Department of Aquatic Chemistry, Federal Institute of Hydrology , D-56002 Koblenz, Germany
| | - David L Sedlak
- ReNUWIt Engineering Research Center and Department of Civil & Environmental Engineering, University of California at Berkeley , Berkeley, California 94720, United States
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Zhang N, Schindelka J, Herrmann H, George C, Rosell M, Herrero-Martín S, Klán P, Richnow HH. Investigation of humic substance photosensitized reactions via carbon and hydrogen isotope fractionation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:233-42. [PMID: 25427194 DOI: 10.1021/es502791f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Humic substances (HS) acting as photosensitizers can generate a variety of reactive species, such as OH radicals and excited triplet states ((3)HS*), promoting the degradation of organic compounds. Here, we apply compound-specific stable isotope analysis (CSIA) to characterize photosensitized mechanisms employing fuel oxygenates, such as methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE), as probes. In oxygenated aqueous media, Λ (Δδ(2)H/Δδ(13)C) values of 23 ± 3 and 21 ± 3 for ETBE obtained by photosensitization by Pahokee Peat Humic Acid (PPHA) and Suwannee River Fulvic Acid (SRFA), respectively, were in the range typical for H-abstraction by OH radicals generated by photolysis of H2O2 (Λ = 24 ± 2). However, (3)HS* may become a predominant reactive species upon the quenching of OH radicals (Λ = 14 ± 1), and this process can also play a key role in the degradation of ETBE by PPHA photosensitization in deoxygenated media (Λ = 11 ± 1). This is in agreement with a model photosensitization by rose bengal (RB(2-)) in deoxygenated aqueous solutions resulting in one-electron oxidation of ETBE (Λ = 14 ± 1). Our results demonstrate that the use of CSIA could open new avenues for the assessment of photosensitization pathways.
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Affiliation(s)
- Ning Zhang
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ , Permoserstrasse 15, 04318 Leipzig, Germany
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Avetta P, Marchetti G, Minella M, Pazzi M, De Laurentiis E, Maurino V, Minero C, Vione D. Phototransformation pathways of the fungicide dimethomorph ((E,Z) 4-[3-(4-chlorophenyl)-3-(3,4-dimethoxyphenyl)-1-oxo-2-propenyl]morpholine), relevant to sunlit surface waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 500-501:351-360. [PMID: 25240237 DOI: 10.1016/j.scitotenv.2014.08.067] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 08/19/2014] [Accepted: 08/19/2014] [Indexed: 06/03/2023]
Abstract
Dimethomorph (DMM) is a widely used fungicide that shows low toxicity for birds and mammals but can be quite toxic to aquatic organisms. The persistence of DMM in surface waters is thus of high importance, and this work modelled its water half-life time due to photochemical processes. Depending on environmental conditions (e.g. water chemistry, depth, season), DMM lifetime could vary from a few days to a few months. For lifetimes of a few weeks or shorter, photochemistry would be an important pathway for DMM attenuation in surface waters. Such conditions could be reached in summer, in shallow water bodies with low dissolved organic carbon (DOC) and high nitrate and/or nitrite. The main pathways accounting for DMM photodegradation in environmental waters would be the reactions with OH and with the triplet states of chromophoric dissolved organic matter, (3)CDOM* (under the hypothesis that (3)CDOM* reactivity is well described by the triplet state of anthraquinone-2-sulphonate), while direct photolysis would be less important. The OH pathway would be favoured in low-DOC waters, while the opposite conditions would favour (3)CDOM*. It was possible to detect and identify some intermediates formed upon reaction between DMM and (3)CDOM*, namely N-formylmorpholine, 4-chloroacetophenone and 4-chlorobenzoic acid. The transformation of DMM into the detected compounds would not increase the acute toxicity of the fungicide towards mammals, and the acute effects for freshwater organisms could be decreased significantly.
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Affiliation(s)
- Paola Avetta
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy. http://www.chimicadellambiente.unito.it
| | - Giulia Marchetti
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy; LAV s.r.l., Strada Carignano 58/14, 10024 Moncalieri, TO, Italy. http://www.chimicadellambiente.unito.it
| | - Marco Minella
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy. http://www.chimicadellambiente.unito.it
| | - Marco Pazzi
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy. http://www.chimicadellambiente.unito.it
| | - Elisa De Laurentiis
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy. http://www.chimicadellambiente.unito.it
| | - Valter Maurino
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy. http://www.chimicadellambiente.unito.it
| | - Claudio Minero
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy. http://www.chimicadellambiente.unito.it
| | - Davide Vione
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy; Università degli Studi di Torino, Centro Interdipartimentale NatRisk, Via Leonardo da Vinci 44, 10095 Grugliasco, TO, Italy.
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Neshchadin D, Batchelor SN, Bilkis I, Gescheidt G. Short-lived Phenoxyl Radicals Formed from Green-Tea Polyphenols and Highly Reactive Oxygen Species: An Investigation by Time-Resolved EPR Spectroscopy. Angew Chem Int Ed Engl 2014; 53:13288-92. [DOI: 10.1002/anie.201407995] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 09/06/2014] [Indexed: 12/15/2022]
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Neshchadin D, Batchelor SN, Bilkis I, Gescheidt G. Kurzlebige Phenoxylradikale aus Polyphenolen des Grünen Tees und hochreaktiven Sauerstoffspezies: Detektion mittels zeitauflösender EPR-Spektroskopie. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201407995] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Vione D, Maurino V, Minero C. Photosensitised humic-like substances (HULIS) formation processes of atmospheric significance: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:11614-11622. [PMID: 24281675 DOI: 10.1007/s11356-013-2319-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 10/31/2013] [Indexed: 06/02/2023]
Abstract
Photosensitised reactions can produce compounds that closely resemble the humic-like substances (HULIS) occurring in atmospheric aerosols. The relevant processes have been observed in the laboratory, in both gas-solid systems and the aqueous phase. They involve triplet sensitisers (such as benzophenones, anthraquinones and nitroaromatic compounds, which yield reactive triplet states after sunlight absorption) or photogenerated oxidants like (•)OH, in the presence of substrates that undergo oligomerisation reactions upon oxidation. Formation of higher molecular weight compounds, modification of the wettability properties of organic films and photoproduction of substances with humic-like fluorescence properties have been observed as a consequence of the photosensitised reactions. Ozone plays an important but still not completely clear role in gas-solid systems.
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Affiliation(s)
- Davide Vione
- Dipartimento di Chimica, Università degli Studi di Torino, Via P. Giuria 5, 10125, Torino, Italy,
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Bahnmüller S, von Gunten U, Canonica S. Sunlight-induced transformation of sulfadiazine and sulfamethoxazole in surface waters and wastewater effluents. WATER RESEARCH 2014; 57:183-92. [PMID: 24721665 DOI: 10.1016/j.watres.2014.03.019] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 03/06/2014] [Accepted: 03/08/2014] [Indexed: 05/26/2023]
Abstract
Sulfadiazine (SD) and sulfamethoxazole (SMX) are widely used sulfonamide antibiotics, which are present as contaminants in surface waters and are known to undergo phototransformation. This kinetic study was conducted to identify the processes responsible for their phototransformation in sunlit surface waters. Water samples from the Thur River (Switzerland) and from a pilot wastewater treatment plant, as well as aqueous solutions of two well-characterized natural dissolved organic matter (DOM) extracts, namely Suwannee River and Pony Lake fulvic acids (SRFA, PLFA), were examined. Both sulfonamides were found to undergo direct and indirect phototransformation, with contributions of excited triplet states of DOM and of effluent organic matter (EfOM) and possibly of hydroxyl radical and other unidentified reactive species. Under simulated sunlight, SMX mainly reacted through direct phototransformation, with a certain contribution of indirect phototransformation occurring for a wastewater effluent. The behavior of SD was found to be more diverse. For river waters, wastewater effluents and PLFA solutions, indirect phototransformation was predominant, while for SRFA solutions direct phototransformation prevailed. The rates of phototransformation of SD were interpreted as the result of a complex interplay between the photosensitizing and the inhibitory effect of DOM/EfOM, with an additional component related to the nitrite ion as a source of photoproduced hydroxyl radical. For typical conditions found in surface waters comparable to the Thur River, phototransformation half-lives on the order of 3-13 d were estimated for the two studied sulfonamides.
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Affiliation(s)
- Sabrina Bahnmüller
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, CH-8092 Zürich, Switzerland
| | - Urs von Gunten
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, CH-8092 Zürich, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Silvio Canonica
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland.
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De Laurentiis E, Prasse C, Ternes TA, Minella M, Maurino V, Minero C, Sarakha M, Brigante M, Vione D. Assessing the photochemical transformation pathways of acetaminophen relevant to surface waters: transformation kinetics, intermediates, and modelling. WATER RESEARCH 2014; 53:235-48. [PMID: 24525071 DOI: 10.1016/j.watres.2014.01.016] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Revised: 01/07/2014] [Accepted: 01/08/2014] [Indexed: 05/04/2023]
Abstract
This work shows that the main photochemical pathways of acetaminophen (APAP) transformation in surface waters would be direct photolysis (with quantum yield of (4.57 ± 0.17)⋅10(-2)), reaction with CO3(-·) (most significant at pH > 7, with second-order rate constant of (3.8 ± 1.1)⋅10(8) M(-1) s(-1)) and possibly, for dissolved organic carbon higher than 5 mg C L(-1), reaction with the triplet states of chromophoric dissolved organic matter ((3)CDOM*). The modelled photochemical half-life time of APAP in environmental waters would range from days to few weeks in summertime, which suggests that the importance of phototransformation might be comparable to biodegradation. APAP transformation by the main photochemical pathways yields hydroxylated derivatives, ring-opening compounds as well as dimers and trimers (at elevated concentration levels). In the case of (3)CDOM* (for which the triplet state of anthraquinone-2-sulphonate was used as proxy), ring rearrangement is also hypothesised. Photochemistry would produce different transformation products (TPs) of APAP than microbial biodegradation or human metabolism, thus the relevant TPs might be used as markers of APAP photochemical reaction pathways in environmental waters.
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Affiliation(s)
- Elisa De Laurentiis
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy
| | - Carsten Prasse
- Federal Institute of Hydrology (BfG), Referat G2, Am Mainzer Tor 1, 56068 Koblenz, Germany
| | - Thomas A Ternes
- Federal Institute of Hydrology (BfG), Referat G2, Am Mainzer Tor 1, 56068 Koblenz, Germany
| | - Marco Minella
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy
| | - Valter Maurino
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy
| | - Claudio Minero
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy
| | - Mohamed Sarakha
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, BP 80026, F-63177 Aubière, France
| | - Marcello Brigante
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, BP 80026, F-63177 Aubière, France
| | - Davide Vione
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy; Università degli Studi di Torino, Centro Interdipartimentale NatRisk, Via L. Da Vinci 44, 10095 Grugliasco, TO, Italy.
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Brigante M, Minella M, Mailhot G, Maurino V, Minero C, Vione D. Formation and reactivity of the dichloride radical (Cl2(-·)) in surface waters: a modelling approach. CHEMOSPHERE 2014; 95:464-9. [PMID: 24383074 DOI: 10.1016/j.chemosphere.2013.09.098] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The occurrence of Cl2(-·) in natural waters would depend on the budget between triplet-sensitised photogeneration (which might have second-order rate constant of 10(7)-10(9) M(-1) s(-1)) and scavenging by dissolved organic matter (DOM, with possible rate constant of 10-10(3) L (mg C)(-1) s(-1)). The steady-state [Cl2(-·)] in brackish to saline waters might be in the range of 10(-14)-10(-12) M in mid-latitude summertime, coherently with data of phenol photochlorination in seawater. Steady-state [Cl2(-·)] would be enhanced by chloride (up to a plateau above 0.1 M Cl(-)) and inhibited by DOM. The radical Cl2(-·) would also be a major oxidant of nitrite to the nitrating agent (·)NO2 in brackish- and salt-water. This issue may explain the sustained formation of nitrophenols in phenol-spiked seawater and in natural brackish waters impacted by phenolic pollutants (Rhône delta, Southern France).
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De Laurentiis E, Buoso S, Maurino V, Minero C, Vione D. Optical and photochemical characterization of chromophoric dissolved organic matter from lakes in Terra Nova Bay, Antarctica. Evidence of considerable photoreactivity in an extreme environment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:14089-14098. [PMID: 24245606 DOI: 10.1021/es403364z] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Water samples from shallow lakes located in Terra Nova Bay, Antarctica, were taken in the austral summer season and characterized for chemical composition, optical features, fluorescence excitation-emission matrix (EEM) and photoactivity toward the generation of (•)OH, (1)O2, and (3)CDOM* (triplet states of chromophoric dissolved organic matter). The optical properties suggested that CDOM would be largely of aquagenic origin and possibly characterized by limited photochemical processing before sampling. Moreover, the studied samples were highly photoactive and the quantum yields for the generation of (3)CDOM* and partially of (1)O2 and (•)OH were considerably higher compared to water samples from temperate environments. This finding suggests that water in the studied lakes would have considerable ability to photosensitize the degradation of dissolved compounds during the austral summer, possibly including organic pollutants, also considering that the irradiance conditions of the experiments were not far from those observed on the Antarctic coast during the austral summer.
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Affiliation(s)
- Elisa De Laurentiis
- Università di Torino , Dipartimento di Chimica, Via Pietro Giuria 5, 10125 Torino, Italy
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Marchetti G, Minella M, Maurino V, Minero C, Vione D. Photochemical transformation of atrazine and formation of photointermediates under conditions relevant to sunlit surface waters: laboratory measures and modelling. WATER RESEARCH 2013; 47:6211-6222. [PMID: 23972676 DOI: 10.1016/j.watres.2013.07.038] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 06/03/2013] [Accepted: 07/25/2013] [Indexed: 06/02/2023]
Abstract
By combination of laboratory experiments and modelling, we show here that the main photochemical pathways leading to the transformation of atrazine (ATZ, 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) in surface waters would be direct photolysis, reaction with ·OH and with the triplet states of chromophoric dissolved organic matter ((3)CDOM*). Reaction with (3)CDOM* would be favoured by elevated water depth and dissolved organic carbon content, while opposite conditions would favour direct photolysis and OH reaction. Desethylatrazine (DEA, 4-amino-2-chloro-6-isopropylamino-1,3,5-triazine) was the main detected intermediate of ATZ phototransformation. Its formation yield from ATZ (ratio of DEA formation to ATZ transformation rate) would be 0.93 ± 0.14 for ·OH, 0.55 ± 0.05 for (3)CDOM*, and 0.20 ± 0.02 for direct photolysis. Direct photolysis and ·OH reaction also yielded 4-amino-2-hydroxy-6-isopropylamino-1,3,5-triazine (DEAOH) and 6-amino-2-chloro-4-ethylamino-1,3,5-triazine (DIA). Reaction with excited triplet states also produced 2-hydroxy-4,6-diamino-1,3,5-triazine (AN) and 2-chloro-4,6-diamino-1,3,5-triazine (CAAT). Therefore, if biological processes can be neglected and if the low formation yields do not prevent detection, DEAOH and DIA could be used as markers of ATZ direct photolysis and ·OH reaction, while AN and CAAT could be markers of ATZ reaction with (3)CDOM*. Model predictions concerning ATZ phototransformation were compared with available field data from the literature. When sufficiently detailed field information was provided, good agreement was found with the model.
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Affiliation(s)
- Giulia Marchetti
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy(1); LAV s.r.l., Strada Carignano 58/14, 10024 Moncalieri (TO), Italy(2)
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Ruggeri G, Ghigo G, Maurino V, Minero C, Vione D. Photochemical transformation of ibuprofen into harmful 4-isobutylacetophenone: pathways, kinetics, and significance for surface waters. WATER RESEARCH 2013; 47:6109-21. [PMID: 23972675 DOI: 10.1016/j.watres.2013.07.031] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 06/21/2013] [Accepted: 07/19/2013] [Indexed: 05/16/2023]
Abstract
The harmful compound 4-isobutylacetophenone (IBAP) can be formed photochemically from the anti-inflammatory drug ibuprofen (IBP), upon direct photolysis (yield 25 ± 7%, μ ± σ), reaction with ·OH (yield 2.3 ± 0.1%) and reaction with triplet states of chromophoric dissolved organic matter, (3)CDOM* (yield 31 ± 4%). In the latter case, anthraquinone-2-sulphonate was used as CDOM proxy. The three processes would account for most of the photochemical transformation of IBP and IBAP in surface waters. IBAP formation from IBP involves the propanoic acid chain, which is more reactive than the aromatic ring as shown by quantum mechanical calculations. IBAP is expected to undergo slightly faster photochemical transformation than IBP in surface waters, with a modelled pseudo-first order rate constant that is higher by 1.5-1.9 times compared to IBP. Due to fairly high formation yields and depending on IBP emission scenarios, photochemical modelling suggests that IBAP could reach concentration values up to ~15% of IBP in surface waters, thus being a potentially important transformation intermediate. This issue prompts for the need of field studies that provide information on IBAP environmental occurrence, which is virtually unknown at the present moment.
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Affiliation(s)
- Giulia Ruggeri
- Università degli Studi di Torino, Dipartimento di Chimica, Via Pietro Giuria 5-7, 10125 Torino, Italy
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Lee E, Glover CM, Rosario-Ortiz FL. Photochemical formation of hydroxyl radical from effluent organic matter: role of composition. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:12073-12080. [PMID: 24053683 DOI: 10.1021/es402491t] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The photochemical formation of hydroxyl radical (HO(•)) from effluent organic matter (EfOM) depends upon the chemical properties of this heterogeneous mixture. In this study, two EfOM samples collected from wastewater treatment plants (WWTP A and B) were fractionated by both hydrophobicity (bulk and non-humic) and apparent molecular weight (AMW). The apparent quantum yield for HO(•) formation (ΦHO(•)) and the maximum fluorescence quantum yield (ΦF) were subsequently measured for each subfraction. The formation rates of HO(•) (considering only the hydrogen-peroxide-independent pathways) for the bulk waters were 4.8 × 10(-10) and 9.6 × 10(-11) M s(-1) for WWTP A and B, respectively. For the AMW fractions, the values of ΦHO(•) increased as the AMW of the material decreased. For the WWTP A sample, the ΦHO(•) increased from 2.54 × 10(-4) (bulk water) to 6.29 × 10(-4) for the <1 kDa fraction, and for the WWTP B sample, the value of ΦHO(•) increased from 6.50 × 10(-5) for bulk water to 3.45 × 10(-4) for the <1 kDa fraction. In the case of fluorescence, the values of ΦF ranged from 2.37 × 10(-4) (bulk water) to 3.48 × 10(-4) (<1 kDa fraction) for WWTP A and 3.19 × 10(-4) (bulk water) to 5.75 × 10(-4) (<1 kDa fraction) for WWTP B. There was a linear correlation between ΦHO(•) and ΦF, suggesting that different photophysical processes occur in the chemical components of the fractions. Understanding the formation of HO(•) from EfOM is essential for understanding wastewater-impacted aquatic systems because these results influence the photochemical degradation and mineralization of trace organic contaminants.
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Affiliation(s)
- Eunkyung Lee
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado , Boulder, Colorado 80309, United States
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Vione D, Caringella R, De Laurentiis E, Pazzi M, Minero C. Phototransformation of the sunlight filter benzophenone-3 (2-hydroxy-4-methoxybenzophenone) under conditions relevant to surface waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 463-464:243-251. [PMID: 23810862 DOI: 10.1016/j.scitotenv.2013.05.090] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 05/10/2013] [Accepted: 05/28/2013] [Indexed: 06/02/2023]
Abstract
The UV filter benzophenone-3 (BP3) has UV photolysis quantum yield ΦBP3=(3.1±0.3)·10(-5) and the following second-order reaction rate constants: with (•)OH, k(BP3,(•)OH)=(2.0±0.4)·10(10) M(-1) s(-1); with the triplet states of chromophoric dissolved organic matter ((3)CDOM*), K(BP3,(3)CDOM*)=(1.1±0.1)·10(9) M(-1) s(-1); with (1)O2, k(BP3,(1)O2)=(2.0±0.1)·10(5) M(-1) s(-1), and with CO3(-•), k(BP3,CO3(-•))<5·10(7) M(-1) s(-1). These data allow the modelling of BP3 photochemical transformation, which helps filling the knowledge gap about the environmental persistence of this compound. Under typical surface-water conditions, direct photolysis and reactions with (•)OH and (3)CDOM* would be the main processes of BP3 phototransformation. Reaction with (•)OH would prevail at low DOC, direct photolysis at intermediate DOC (around 5 mg C L(-1)), and reaction with (3)CDOM* at high DOC. If the reaction rate constant with CO3(-•) is near the upper limit of experimental measures (5·10(7) M(-1) s(-1)), the CO3(-•) degradation process could be somewhat important for DOC<1 mg C L(-1). The predicted half-life time of BP3 in surface waters under summertime conditions would be of some weeks, and it would increase with increasing depth and DOC. BP3 transformation intermediates were detected upon reaction with (•)OH. Two methylated derivatives were tentatively identified, and they were probably produced by reaction between BP3 and fragments arising from photodegradation. The other intermediates were benzoic acid (maximum concentration ~10% of initial BP3) and benzaldehyde (1%).
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Affiliation(s)
- Davide Vione
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy; Università degli Studi di Torino, Centro Interdipartimentale NatRisk, Via L. Da Vinci 44, 10095 Grugliasco (TO), Italy.
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Benitez FJ, Acero JL, Real FJ, Roldan G, Rodriguez E. Photolysis of model emerging contaminants in ultra-pure water: kinetics, by-products formation and degradation pathways. WATER RESEARCH 2013; 47:870-80. [PMID: 23218246 DOI: 10.1016/j.watres.2012.11.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 11/07/2012] [Accepted: 11/10/2012] [Indexed: 05/15/2023]
Abstract
The photolysis of five frequent emerging contaminants (Benzotriazole, Chlorophene, N,N-diethyl-m-toluamide or DEET, Methylindole, and Nortriptyline HCl) was investigated in ultrapure water under monochromatic ultraviolet radiation at 254 nm and by a combination of UV and hydrogen peroxide. The results revealed that the photolysis rates followed first-order kinetics, with rate constant values depending on the nature of the specific compound, the pH, and the presence or absence of the scavenger tert-butanol. Quantum yields were also determined and values in the range of 53.8 × 10⁻³ - 9.4 × 10⁻³ mol E⁻¹ for Benzotriazole, 525 × 10⁻³ - 469 × 10⁻³ mol E⁻¹ for Chlorophene, 2.8 × 10⁻³ - 0.9 × 10⁻³ mol E⁻¹ for DEET, 108 × 10⁻³ - 165 × 10⁻³ mol E⁻¹ for Methylindole, and 13.8 × 10⁻³ - 15.0 × 10⁻³ mol E⁻¹ for Nortriptyline were obtained. The study also found that the UV/H₂O₂ process enhanced the oxidation rate in comparison to direct photolysis. High-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS) technique was applied to the concentrations evaluation and further identification of the parent compounds and their by-products, which allowed the proposal of the degradation pathways for each compound. Finally, in order to assess the aquatic toxicity in the photodegradation of these compounds, the Vibrio fischeri acute toxicity test was used, and the results indicated an initial increase of this parameter in all cases, followed by a decrease in the specific case of Benzotriazole, DEET, Methylindole, and Chlorophene.
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MESH Headings
- Aliivibrio fischeri/drug effects
- Aliivibrio fischeri/growth & development
- Anti-Infective Agents, Local/analysis
- Anti-Infective Agents, Local/chemistry
- Anti-Infective Agents, Local/toxicity
- Antidepressive Agents, Tricyclic/analysis
- Antidepressive Agents, Tricyclic/chemistry
- Antidepressive Agents, Tricyclic/toxicity
- DEET/analysis
- DEET/chemistry
- Dichlorophen/analogs & derivatives
- Dichlorophen/analysis
- Free Radical Scavengers/chemistry
- Hydrogen Peroxide/chemistry
- Hydrogen-Ion Concentration
- Insect Repellents/analysis
- Insect Repellents/chemistry
- Insect Repellents/toxicity
- Kinetics
- Models, Chemical
- Nortriptyline/analysis
- Nortriptyline/chemistry
- Nortriptyline/toxicity
- Oxidants/chemistry
- Oxidation-Reduction
- Photolysis
- Skatole/toxicity
- Triazoles/analysis
- Triazoles/toxicity
- Ultraviolet Rays
- Water/chemistry
- Water Pollutants, Chemical/analysis
- Water Pollutants, Chemical/chemistry
- Water Pollutants, Chemical/toxicity
- Water Purification/methods
- tert-Butyl Alcohol/chemistry
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Affiliation(s)
- F Javier Benitez
- Departamento de Ingeniería Química, Universidad de Extremadura, Facultad de Ciencias, 06071 Badajoz, Spain.
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De Laurentiis E, Maurino V, Minero C, Vione D, Mailhot G, Brigante M. Could triplet-sensitised transformation of phenolic compounds represent a source of fulvic-like substances in natural waters? CHEMOSPHERE 2013; 90:881-884. [PMID: 23036323 DOI: 10.1016/j.chemosphere.2012.09.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 08/05/2012] [Accepted: 09/08/2012] [Indexed: 06/01/2023]
Abstract
Here we show that fluorescent compounds that could be classified as "M-like" (marine-like) fulvic acids are formed upon phototransformation of phenol by a triplet sensitiser (anthraquinone-2-sulphonate, AQ2S). The relevant process most likely involves phenol oxidation to phenoxyl radical by triplet AQ2S, followed by dimerisation of phenoxyl radicals into phenoxyphenols and dihydroxybiphenyls. It might be the first step of an oligomerization process that bears resemblance with the expected formation pathways of humic-like substances (HULIS) in the atmosphere. Such a process could account for the formation in surface waters of compounds having similar fluorescence properties as "M-like" fulvic acids. Presently it is thought that such species are formed upon photo-fragmentation of larger humic and fulvic acids ("top-down" pathway), and we propose that an opposite, "bottom-up" pathway could also be operational.
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Affiliation(s)
- Elisa De Laurentiis
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy
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De Laurentiis E, Minella M, Maurino V, Minero C, Mailhot G, Sarakha M, Brigante M, Vione D. Assessing the occurrence of the dibromide radical (Br₂⁻•) in natural waters: measures of triplet-sensitised formation, reactivity, and modelling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2012; 439:299-306. [PMID: 23085471 DOI: 10.1016/j.scitotenv.2012.09.037] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 09/17/2012] [Accepted: 09/17/2012] [Indexed: 05/15/2023]
Abstract
The triplet state of anthraquinone-2-sulphonate (AQ2S) is able to oxidise bromide to Br(•)/Br(2)(-•), with rate constant (2-4)⋅10(9)M(-1)s(-1) that depends on the pH. Similar processes are expected to take place between bromide and the triplet states of naturally occurring chromophoric dissolved organic matter ((3)CDOM*). The brominating agent Br(2)(-•) could thus be formed in natural waters upon oxidation of bromide by both (•)OH and (3)CDOM*. Br(2)(-•) would be consumed by disproportionation into bromide and bromine, as well as upon reaction with nitrite and most notably with dissolved organic matter (DOM). By using the laser flash photolysis technique, and phenol as model organic molecule, a second-order reaction rate constant of ~3⋅10(2)L(mg C)(-1)s(-1) was measured between Br(2)(-•) and DOM. It was thus possible to model the formation and reactivity of Br(2)(-•) in natural waters, assessing the steady-state [Br(2)(-•)]≈10(-13)-10(-12)M. It is concluded that bromide oxidation by (3)CDOM* would be significant compared to oxidation by (•)OH. The (3)CDOM*-mediated process would prevail in DOM-rich and bromide-rich environments, the latter because elevated bromide would completely scavenge (•)OH. Under such conditions, (•)OH-assisted formation of Br(2)(-•) would be limited by the formation rate of the hydroxyl radical. In contrast, the formation rate of (3)CDOM* is much higher compared to that of (•)OH in most surface waters and would provide a large (3)CDOM* reservoir for bromide to react with. A further issue is that nitrite oxidation by Br(2)(-•) could be an important source of the nitrating agent (•)NO(2) in bromide-rich, nitrite-rich and DOM-poor environments. Such a process could possibly account for significant aromatic photonitration observed in irradiated seawater and in sunlit brackish lagoons.
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Affiliation(s)
- Elisa De Laurentiis
- Università degli Studi di Torino, Dipartimento di Chimica, Via P. Giuria 5, 10125 Torino, Italy. http://www.chimicadellambiente.unito.it
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De Laurentiis E, Chiron S, Kouras-Hadef S, Richard C, Minella M, Maurino V, Minero C, Vione D. Photochemical fate of carbamazepine in surface freshwaters: laboratory measures and modeling. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:8164-73. [PMID: 22795037 DOI: 10.1021/es3015887] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
It is shown here that carbamazepine (CBZ) would undergo direct photolysis and reaction with (•)OH as the main phototransformation pathways in surface waters. Environmental lifetimes are expected to vary from a few weeks to several months, and predictions are in good agreement with available field data. Acridine (I) and 10,11-dihydro-10,11-trans-dihydroxy-CBZ (V) are the main quantified phototransformation intermediates upon direct photolysis and (•)OH reaction, respectively. The photochemical yield of mutagenic I from CBZ is in the 3-3.5% range, and it is similar for both direct photolysis and (•)OH reaction: it would undergo limited variation with environmental conditions. In contrast, the yield of V would vary in the 4-8.5% range depending on the conditions, because V is formed from CBZ by (•)OH (9.0% yield) more effectively than upon direct photolysis (1.4% yield). Other important photointermediates, mostly formed from CBZ upon (•)OH reaction, are an aromatic-ring-dihydroxylated CBZ (VI) and N,N-bis(2-carboxyphenyl)urea (VII). Compounds VI and VII are formed by photochemistry and are not reported as human metabolites; thus, they could be used as tracers of CBZ phototransformation in surface waters. Interestingly, VI has recently been detected in river water.
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Affiliation(s)
- Elisa De Laurentiis
- Dipartimento di Chimica, Università degli Studi di Torino, Via P. Giuria 5, 10125 Torino, Italy
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