1
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Yuan X, Zhang D, Liang C, Zhang X. Spontaneous Reduction of Transition Metal Ions by One Electron in Water Microdroplets and the Atmospheric Implications. J Am Chem Soc 2023; 145:2800-2805. [PMID: 36705987 DOI: 10.1021/jacs.3c00037] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Freshman chemistry teaches that Fe3+ and Cu2+ ions are stable in water solutions, but their reduced forms, Fe2+ and Cu+, cannot exist in water as the major oxidation state due to the fast oxidation by O2 and/or disproportionation. Contrary to these well-known facts, significant fractions of dissolved Fe and Cu species exist in their reduced oxidation states in atmospheric water such as deliquesced aerosols, clouds, and fog droplets. Current knowledge attributes these phenomena to the stabilization of the lower oxidation states by the complexation of ligands and the various photochemical or thermal pathways that can reduce the higher oxidation states. In this study, by spraying the water solutions of transition metal ions into microdroplets, we show the results of the spontaneous reduction of ligated Fe(III) and Cu(II) species into Fe(II) and Cu(I) species, presenting a previously unknown source of reduced transition metal ions in atmospheric water. It is the spontaneously generated electrons in water microdroplets that are responsible for the reduction. Control experiments in the atmosphere and in a glove box filled with precisely controlled gaseous contents reveal that O2, CO2, and NO2 are the major competitors for the electrons, forming O2-, HCO2-, and NO2-, respectively. Taking these findings together, we opine that microdroplet chemistry might play significant but previously underestimated roles in atmospheric redox chemistry.
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Affiliation(s)
- Xu Yuan
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Dongmei Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Chiyu Liang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Xinxing Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China.,Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, China
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2
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Tong Y, Wang X, Sun Z, Gao J. Two transformation pathways of Acetaminophen with Fe 3+ saturated clay particles in dark or light. CHEMOSPHERE 2021; 278:130399. [PMID: 33838409 DOI: 10.1016/j.chemosphere.2021.130399] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 03/07/2021] [Accepted: 03/22/2021] [Indexed: 06/12/2023]
Abstract
Acetaminophen (AP) has been frequently detected in different environments due to its wide usage as a common analgesic and antipyretic pharmaceutical. Excess residual of AP in the environment may cause biological risk. However, information about its environmental behaviors was limited, especially the interactions with clay minerals. In this study, AP transformation mediated by Fe3+ saturated clay particles was systematically investigated. The results showed 47.6 ± 1.1% or 78.9 ± 0.5% of AP was removed in the presence of Fe3+-montmorillonite respectively in dark or under simulated sunlight irradiation after 10 h. The hypothesized mechanism was that exchangeable ferric ions can either obtain electron from AP to form AP radical, or produce •OH under light, which can further react with AP. In dark condition, AP radicals could cross-couple with each other to form dimers, while oxidation products were also detected under light irradiation due to •OH attacking. Moreover, higher concentration of dissolved oxygen (DO) facilitated Fe3+ regeneration on clay surfaces and more reactive Fe species distributed in lower pH, which could significantly enhance the removal of AP both in dark and light. Results of this study revealed that clay minerals played important roles in the abiotic transformation of AP either in dark or under light irradiation, and oligomerization other than mineralization were the dominant processes.
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Affiliation(s)
- Yunping Tong
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, PR China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xinghao Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, PR China
| | - Zhaoyue Sun
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, PR China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Juan Gao
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, PR China.
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3
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Dong Y, Peng W, Liu Y, Wang Z. Photochemical origin of reactive radicals and halogenated organic substances in natural waters: A review. JOURNAL OF HAZARDOUS MATERIALS 2021; 401:123884. [PMID: 33113752 DOI: 10.1016/j.jhazmat.2020.123884] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 08/14/2020] [Accepted: 08/23/2020] [Indexed: 06/11/2023]
Abstract
Halogenated organic compounds, also termed organohalogens, were initially regarded to be of almost exclusively anthropogenic origin. However, recent research has demonstrated that photochemical reactions are important abiotic sources of organohalogen compounds in sunlit surface waters. Halide ions (X-, X represents Cl, Br and I) are common anions in natural waters and might be oxidized by reactive species originated from photochemistry of dissolved organic matter (DOM) or inorganic photoactive species. The resulting reactive halogen species may react with organic substances with diverse bimolecular reaction rate constants, depending on the complexity and structure of organic substances. Therefore, the chemical mechanism of halogenation remains challenging to be fully elucidated. To better understand the trends in the existing data and to identify the knowledge gaps that may merit further investigation, this review gives an integrative summary on the sources of reactive oxygen species (ROS) and halogen radicals (X/X2-). Photochemical halogenation of phenolic compounds and formation of methyl halide and brominated organic pollutants are highlighted. By evaluating existing literature and identifying some uncertainties, this review emphasizes the environmental significance of sunlight-driven halogenation and proposes further research directions on mechanistic investigation and rational experimental design close to natural systems.
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Affiliation(s)
- Yongxia Dong
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Wenya Peng
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Yunjiao Liu
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Zhaohui Wang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Shanghai 200241, China; Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, 3663 N. Zhongshan Road, Shanghai 200062, China.
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4
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Huang D, Wang J, Xia H, Zhang Y, Bao F, Li M, Chen C, Zhao J. Enhanced Photochemical Volatile Organic Compounds Release from Fatty Acids by Surface-Enriched Fe(III). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:13448-13457. [PMID: 33081467 DOI: 10.1021/acs.est.0c03793] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Both Fe(III) and fatty acids are ubiquitous and important species in environmental waters. Because they are amphipathic, many fatty acids are surface active and prone to enrichment at the air-water interface. Here, we report that by using nonanoic acid (NA) as a model fatty acid, coexisting Fe(III), even at concentrations as low as 1 μM, markedly enhanced the photochemical release of NA-derived volatile organic compounds (VOCs) such as octanal and octane into the air. Further studies indicated that the surface-enriched fatty acids dramatically increase the local concentration of Fe(III) at the water surface, which enables Fe(III)-mediated photochemical reactions to take place at the air-water interface, and the VOCs facilely produced by fatty acid photooxidation can then be released into the air. Moreover, the product distribution in the Fe(III)-mediated reactions was largely different from that in other photochemical systems, and a mechanism based on photochemical decarboxylation is proposed. Considering that the coexistence of fatty acids and Fe(III) in the environment is common, the enhanced photochemical release of VOCs by surface-enriched fatty acids and Fe(III) may be an important channel for the atmospheric emission of VOCs, which are known to play an essential role in the formation of ozone and secondary organic aerosols.
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Affiliation(s)
- Di Huang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jinzhao Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Hongling Xia
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yue Zhang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Fengxia Bao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Meng Li
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chuncheng Chen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jincai Zhao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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5
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Yermakov AN, Purmal AP. Iron-Catalyzed Oxidation of Sulfite: From Established Results to a New Understanding. PROGRESS IN REACTION KINETICS AND MECHANISM 2019. [DOI: 10.3184/007967403103165503] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A survey is made of the iron-catalyzed oxidation of sulfite describing a conceptual framework to explain the key processes involved, with a focus on kinetics. Perhaps most importantly, the incorporation of the HSO5- + Fe(II) step into the regeneration of catalytically active ferric ions which does not deplete its role over the iron redox cycle. The radical-radical recombination SO5-• + SO5-•, which terminates the cycling between ferric and ferrous ions, represents a gross but not a net loss of the chain-carriers, because nearly all of them are reformed through the branching step HSO5- + Fe(II) → Fe2+ + H2O + SO4-•, [Formula: see text] in just a few seconds or somewhat longer. A branching mechanism is thus the only possible means of allowing the catalytic process to reach a stationary state. Observations that may be considered as evidence (fingerprints) of rate variations in sulfite depletion due to the branching mechanism are explored in detail, and the related dynamics of the chain-carriers and metal ions cycles are discussed. In particular, the most important is found to be the aspect related to the intrinsic limitation of the cycle of metal ions. This limitation governs the extent of the oxidative/reducing potential of sulfite solutions with respect to the Fe(III/II) couple, thereby governing the quasi-state partioning between ferric and ferrous ions. Such a view enables examination of those conditions under which the limitation to the rate of the catalytic reaction is controlled by the reduction or re-oxidation of ferric ions. Readily applicable kinetic criteria and kinetic diagrams to delimit the conditions are given. In such a framework, the majority of known anomalies of the catalytic reaction receive an explanation.
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Affiliation(s)
- Alexander N. Yermakov
- Institute for Energy Problems of Chemical Physics, Semenoff's Institute for Chemical Physics, Russian Academy of Sciences Leninsky Prospect 38, Bldg. 2, 119334, Moscow, Russia
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6
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Buxton GV, Salmon GA. On the Chemistry of Inorganic Free Radicals in Cloud Water. PROGRESS IN REACTION KINETICS AND MECHANISM 2019. [DOI: 10.3184/007967403103165512] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The chemistry by which the inorganic free radicals •OH, HO2•, O2•-, SOx•- (x = 3, 4, 5), NO3•, Cl• and Cl2•- lead to the formation of acid rain by the oxidation of sulfur dioxide and organic pollutants in cloud water is discussed in detail. Also considered are the sources of the radicals, their relative reactivities, their inter-conversion and the origins of the pollutants with which they react.
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7
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Lallement A, Vinatier V, Brigante M, Deguillaume L, Delort AM, Mailhot G. First evaluation of the effect of microorganisms on steady state hydroxyl radical concentrations in atmospheric waters. CHEMOSPHERE 2018; 212:715-722. [PMID: 30179836 DOI: 10.1016/j.chemosphere.2018.08.128] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 08/22/2018] [Accepted: 08/24/2018] [Indexed: 06/08/2023]
Abstract
Clouds are complex multiphasic media where efficient chemical reactions take place and where microorganisms have been found to be metabolically active. Hydroxyl radical is the main oxidant in cloud water, and more generally in the atmosphere, during the day and drives the cloud oxidative capacity. However, only one measurement of the steady state hydroxyl radical concentrations in cloud water has been reported so far. Cloud chemistry models are used to estimate the hydroxyl radical concentrations with values ranging from 10-12 to 10-15 M that are surely overestimated due to a lack of knowledge about the speciation of the organic matter acting as a sink for hydroxyl radicals. The aim of this work is to quantify the concentration of hydroxyl radicals at steady state in rain and cloud waters and to measure the impact of native microflora on this concentration. First, the non-toxicity of terephthalic acid as probe is controlled before the analysis in real atmospheric water samples. Higher concentrations of hydroxyl radicals are found in cloud waters than in rain waters, with a mean value "1.6 ± 1.5" × 10-16 M and "7.2 ± 5.0" × 10-16 M for rain and cloud waters respectively and no real impact of microorganisms was observed. This method allows the measurement of steady state hydroxyl radical levels at very low concentrations (down to 10-17 M) and it is biocompatible, fast and easy to handle. It is a useful tool, complementary to other methods, to give a better overview of atmospheric water oxidant capacity.
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Affiliation(s)
- A Lallement
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France
| | - V Vinatier
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France
| | - M Brigante
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France
| | - L Deguillaume
- Université Clermont Auvergne, CNRS, Laboratoire de Météorologie Physique, 63000, Clermont-Ferrand, France
| | - A M Delort
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France.
| | - G Mailhot
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France.
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8
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Sihvonen SK, Murphy KA, Washton NM, Altaf MB, Mueller KT, Freedman MA. Effect of Acid on Surface Hydroxyl Groups on Kaolinite and Montmorillonite. Z PHYS CHEM 2017. [DOI: 10.1515/zpch-2016-0958] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Mineral dust aerosol participates in heterogeneous chemistry in the atmosphere. In particular, the hydroxyl groups on the surface of aluminosilicate clay minerals are important for heterogeneous atmospheric processes. These functional groups may be altered by acidic processing during atmospheric transport. In this study, we exposed kaolinite (KGa-1b) and montmorillonite (STx-1b) to aqueous sulfuric acid and then rinsed the soluble reactants and products off in order to explore changes to functional groups on the mineral surface. To quantify the changes due to acid treatment of edge hydroxyl groups, we use 19F magic angle spinning nuclear magnetic resonance spectroscopy and a probe molecule, 3,3,3-trifluoropropyldimethylchlorosilane. We find that the edge hydroxyl groups (OH) increase in both number and density with acid treatment. Chemical reactions in the atmosphere may be impacted by the increase in OH at the mineral edge.
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Affiliation(s)
- Sarah K. Sihvonen
- Department of Chemistry , The Pennsylvania State University , University Park, PA 16802 , USA
| | - Kelly A. Murphy
- Department of Chemistry , The Pennsylvania State University , University Park, PA 16802 , USA
| | - Nancy M. Washton
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory , Richland, WA 99352 , USA
| | - Muhammad Bilal Altaf
- Department of Chemistry , The Pennsylvania State University , University Park, PA 16802 , USA
| | - Karl T. Mueller
- Physical and Computational Sciences Directorate , Pacific Northwest National Laboratory , Richland, WA 99352 , USA
| | - Miriam Arak Freedman
- Department of Chemistry , The Pennsylvania State University , University Park, PA 16802 , USA
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9
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Zhang Y, Klamerth N, Chelme-Ayala P, Gamal El-Din M. Comparison of classical fenton, nitrilotriacetic acid (NTA)-Fenton, UV-Fenton, UV photolysis of Fe-NTA, UV-NTA-Fenton, and UV-H 2O 2 for the degradation of cyclohexanoic acid. CHEMOSPHERE 2017; 175:178-185. [PMID: 28222372 DOI: 10.1016/j.chemosphere.2017.02.058] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 02/08/2017] [Accepted: 02/10/2017] [Indexed: 06/06/2023]
Abstract
The treatment of a naphthenic acid model compound, cyclohexanoic acid, with classical Fenton, UV-H2O2, UV-Fenton, nitrilotriacetic acid (NTA)-Fenton, UV-NTA-Fenton, and UV photolysis of Fe-NTA processes at pHs 3 and 8 was investigated. At 1.47 mM H2O2, 0.089 mM Fe, and 0.18 mM NTA, the UV-NTA-Fenton process at pH 3 exhibited the highest H2O2 decomposition (100% in 25 min), CHA removal (100% in 12 min) with a rate constant of 0.27 ± 0.025 min-1, and NTA degradation (100% in 6 min). Due to the formation of H2O2-Fe(III)NTA adduct, the total Fe concentration in the UV-NTA-Fenton system (0.063 mM at the end of the reaction) at pH 8 was much higher than that in the UV photolysis of Fe(III)NTA process (0.024 mM). The co-complexing effect of borate buffer helped to keep iron soluble; however, it imposed a negative influence on the CHA degradation in the UV-NTA-Fenton process (68% CHA removal in 60 min in the borate buffer compared to 92% in MilliQ water). The results demonstrated that the most efficient process for the CHA degradation under the experimental conditions was the UV-NTA-Fenton process at pH 3.
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Affiliation(s)
- Ying Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada
| | - Nikolaus Klamerth
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada
| | - Pamela Chelme-Ayala
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada
| | - Mohamed Gamal El-Din
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada.
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10
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Ryding MJ, Fernández I, Uggerud E. Reactions between microhydrated superoxide anions and formic acid. Phys Chem Chem Phys 2017; 19:23176-23186. [DOI: 10.1039/c7cp03820h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Reactions between water clusters containing the superoxide anion, O2˙−(H2O)n (n = 0–4), and formic acid, HCO2H, were studied experimentally in vacuo and modelled using quantum chemical methods.
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Affiliation(s)
- Mauritz Johan Ryding
- Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry
- Department of Chemistry
- University of Oslo
- P.O. Box 1033 Blindern
- NO-0315 Oslo
| | - Israel Fernández
- Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- Facultad de Ciencias Químicas
- Universidad Complutense de Madrid
- 28040-Madrid
- Spain
| | - Einar Uggerud
- Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry
- Department of Chemistry
- University of Oslo
- P.O. Box 1033 Blindern
- NO-0315 Oslo
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11
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Karavoltsos S, Fotiadis F, Michopoulos P, Sakellari A, Plavšić M, Bourletsikas A, Kaoukis K, Thomaidis NS, Dassenakis M, Scoullos M. Organic complexation of copper in throughfall and open field bulk deposition: Influence of the tree canopy of Mediterranean forest ecosystems. CHEMOSPHERE 2017; 167:28-35. [PMID: 27705810 DOI: 10.1016/j.chemosphere.2016.09.131] [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: 04/21/2016] [Revised: 09/16/2016] [Accepted: 09/26/2016] [Indexed: 06/06/2023]
Abstract
The complexing capacity for Cu ions (LT) and the apparent stability constant values (logKapp) were measured in throughfall (TF) and open field bulk deposition (BD), at two Mediterranean forest ecosystems of western Greece. LT was measured for the first time in the TF of natural forests. Concentrations of LT were three-to-four-fold higher in TF (mean ± st.dev: 2014 ± 769 nM for Varetada and 1565 ± 595 nM for Karpenissi) compared to those in BD (531 ± 517 nM and 468 ± 321 nM, respectively). In all TF and BD samples, LT concentrations were significantly higher than the corresponding total Cu concentrations, indicating that Cu was fully complexed. The LT/TOC ratios in TF were found comparable between the two study sites (235 ± 149 nM mg-1 C for Varetada and 256 ± 233 nM mg-1 C for Karpenissi) and with those of BD (226 ± 257 and 163 ± 163 nM mg-1 C, respectively). The determined mean logKapp values were almost identical in TF (6.8 ± 0.7 at Varetada; 6.8 ± 0.6 at Karpenissi) and BD (6.5 ± 0.6 at Varetada; 6.8 ± 0.3 at Karpenissi), pointing to the fact that regardless of the enrichment of TF in ligands (LT(TF) > LT(BD)) the type of binding sites remain the same. The logKapp values which were obtained herewith are similar to those obtained for humic-like substances (HULIS), indicating them as the most widespread type of ligands in BD and TF.
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Affiliation(s)
- Sotirios Karavoltsos
- National and Kapodistrian University of Athens, Department of Chemistry, Laboratory of Environmental Chemistry, Panepistimiopolis, 157 84, Athens, Greece.
| | - Fotios Fotiadis
- National and Kapodistrian University of Athens, Department of Chemistry, Laboratory of Environmental Chemistry, Panepistimiopolis, 157 84, Athens, Greece
| | - Panagiotis Michopoulos
- H.A.O. DEMETER, Institute of Mediterranean Forest Ecosystems, Terma Alkmanos, 115 28 Athens, Greece
| | - Aikaterini Sakellari
- National and Kapodistrian University of Athens, Department of Chemistry, Laboratory of Environmental Chemistry, Panepistimiopolis, 157 84, Athens, Greece
| | - Marta Plavšić
- Ruđer Bošković Institute, Center for Marine and Environmental Research, P.O. Box 180, 10002 Zagreb, Croatia
| | - Athanassios Bourletsikas
- H.A.O. DEMETER, Institute of Mediterranean Forest Ecosystems, Terma Alkmanos, 115 28 Athens, Greece
| | - Kostas Kaoukis
- H.A.O. DEMETER, Institute of Mediterranean Forest Ecosystems, Terma Alkmanos, 115 28 Athens, Greece
| | - Nikolaos S Thomaidis
- National and Kapodistrian University of Athens, Department of Chemistry, Laboratory of Analytical Chemistry, Panepistimiopolis, 157 84, Athens, Greece
| | - Manos Dassenakis
- National and Kapodistrian University of Athens, Department of Chemistry, Laboratory of Environmental Chemistry, Panepistimiopolis, 157 84, Athens, Greece
| | - Michael Scoullos
- National and Kapodistrian University of Athens, Department of Chemistry, Laboratory of Environmental Chemistry, Panepistimiopolis, 157 84, Athens, Greece
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12
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Singhai A, Habib G, Raman RS, Gupta T. Chemical characterization of PM 1.0 aerosol in Delhi and source apportionment using positive matrix factorization. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:445-462. [PMID: 27726085 DOI: 10.1007/s11356-016-7708-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 09/13/2016] [Indexed: 05/28/2023]
Abstract
Fine aerosol fraction (particulate matter with aerodynamic diameter <= 1.0 μm (PM)1.0) over the Indian Institute of Technology Delhi campus was monitored day and night (10 h each) at 30 m height from November 2009 to March 2010. The samples were analyzed for 5 ions (NH4+, NO3-, SO42-, F-, and Cl-) and 12 trace elements (Na, K, Mg, Ca, Pb, Zn, Fe, Mn, Cu, Cd, Cr, and Ni). Importantly, secondary aerosol (sulfate and nitrate) formation was observed during dense foggy events, supporting the fog-smog-fog cycle. A total of 76 samples were used for source apportionment of PM mass. Six factors were resolved by PMF analyses and were identified as secondary aerosol, secondary chloride, biomass burning, soil dust, iron-rich source, and vehicular emission. The geographical location of the sources and/or preferred transport pathways was identified by conditional probability function (for local sources) and potential source contribution function (for regional sources) analyses. Medium- and small-scale metal processing (e.g. steel sheet rolling) industries in Haryana and National Capital Region (NCR) Delhi, coke and petroleum refining in Punjab, and thermal power plants in Pakistan, Punjab, and NCR Delhi were likely contributors to secondary sulfate, nitrate, and secondary chloride at the receptor site. The agricultural residue burning after harvesting season (Sept-Dec and Feb-Apr) in Punjab, and Haryana contributed to potassium at receptor site during November-December and March 2010. The soil dust from North and East Pakistan, and Rajasthan, North-East Punjab, and Haryana along with the local dust contributed to soil dust at the receptor site, during February and March 2010. A combination of temporal behavior and air parcel trajectory ensemble analyses indicated that the iron-rich source was most likely a local source attributed to emissions from metal processing facilities. Further, as expected, the vehicular emissions source did not show any seasonality and was local in origin.
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Affiliation(s)
- Amrita Singhai
- Department of Civil Engineering, Indian Institute of Technology Delhi, Delhi, India
| | - Gazala Habib
- Department of Civil Engineering, Indian Institute of Technology Delhi, Delhi, India.
| | - Ramya Sunder Raman
- Department of Earth and Environmental Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal, India
| | - Tarun Gupta
- Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur, India
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13
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Moussavi M, Matavos-Aramyan S. Chelate-modified fenton treatment of sulfidic spent caustic. KOREAN J CHEM ENG 2016. [DOI: 10.1007/s11814-016-0080-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Li Y, Machala L, Yan W. Fe-Impregnated Mineral Colloids for Peroxide Activation: Effects of Mineral Substrate and Fe Precursor. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:1190-1199. [PMID: 26713453 DOI: 10.1021/acs.est.5b03970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Heterogeneous iron species at the mineral/water interface are important catalysts for the generation of reactive oxygen species at circumneutral pH. One significant pathway leading to the formation of such species arises from deposition of dissolved iron onto mineral colloids due to changes in redox conditions. This study investigates the catalytic properties of Fe impregnated on silica, alumina, and titania nanoparticles (as prototypical mineral colloids). Fe impregnation was carried out by immersing the mineral nanoparticles in dilute Fe(II) or Fe(III) solutions at pH 6 and 3, respectively, in an aerobic environment. The uptake of iron per unit surface area follows the order of nTiO2 > nAl2O3 > nSiO2 for both types of Fe precursors. Impregnation of mineral particles in Fe(II) solutions results in predominantly Fe(III) species due to efficient surface-mediated oxidation. The catalytic activity of the impregnated solids to produce hydroxyl radical (·OH) from H2O2 decomposition was evaluated using benzoic acid as a probe compound under dark conditions. Invariably, the rates of benzoic acid oxidation with different Fe-laden particles increase with the surface density of Fe until a critical density above which the catalytic activity approaches a plateau, suggesting active Fe species are formed predominantly at low surface loadings. The critical surface density of Fe varies with the mineral substrate as well as the aqueous Fe precursor. Fe impregnated on TiO2 exhibits markedly higher activity than its Al2O3 and SiO2 counterparts. The speciation of interfacial Fe is analyzed with diffuse reflectance UV-vis analysis and interpretation of the data in the context of benzoic oxidation rates suggests that the surface activity of the solids for ·OH generation correlates strongly with the isolated (i.e., mononuclear) Fe species. Therefore, iron dispersed on mineral colloids is a significant form of reactive iron surfaces in the aquatic environment.
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Affiliation(s)
- Yue Li
- Department of Civil, Environmental, and Construction Engineering, Texas Tech University , Lubbock, Texas 79409, United States
| | - Libor Machala
- Regional Centre of Advanced Technologies and Materials, Department of Experimental Physics, Palacký University in Olomouc , Olomouc, Czech Republic
| | - Weile Yan
- Department of Civil, Environmental, and Construction Engineering, Texas Tech University , Lubbock, Texas 79409, United States
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15
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Kopcewicz B, Kopcewicz M, Pietruczuk A. The Mössbauer study of atmospheric iron-containing aerosol in the coarse and PM2.5 fractions measured in rural site. CHEMOSPHERE 2015; 131:9-16. [PMID: 25765259 DOI: 10.1016/j.chemosphere.2015.02.038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 01/26/2015] [Accepted: 02/14/2015] [Indexed: 06/04/2023]
Abstract
The size-resolved iron-containing atmospheric aerosol was measured by Mössbauer spectroscopy. The particulate matter (PM) was size-segregated into aerosol<2.5μm in diameter (fine fraction, PM2.5) and aerosol>2.5 μm (coarse fraction). The Mössbauer spectra at room temperature show components assigned to mono- and polymeric species which are products related to hydrolysis of ferric solutions in the atmosphere. In order to extract reliable information regarding the quadrupole splittings necessary for identification of iron-containing compounds, the histogram method was used for evaluation of the Mössbauer spectra. The value and distribution of quadrupole splitting (QS) parameters obtained by this method suggests that the ultra fine particles (<10 nm) identified as a ferrihydrite, hematite and goethite were observed in the spectra both in fine and coarse fraction of the collected aerosol. However, the content of the individual chemical components was different for each fraction. The least crystalline form of ferrihydrite (QS≅0.85 mm) was observed in PM2.5 fraction more frequently than in the coarse fraction. The content of the ultra fine hematite particles which presence was confirmed in low temperature measurements was also larger in PM2.5 fraction than in the coarse fraction. Superparamagnetic behavior of iron-containing atmospheric aerosol was observed in low temperature Mössbauer spectra.
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Affiliation(s)
- Barbara Kopcewicz
- Institute of Geophysics, Polish Academy of Sciences, Ks. Janusza 64, 01-452 Warsaw, Poland.
| | - Michał Kopcewicz
- Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw, Poland.
| | - Aleksander Pietruczuk
- Institute of Geophysics, Polish Academy of Sciences, Ks. Janusza 64, 01-452 Warsaw, Poland.
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16
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Ryding MJ, Debnárová A, Fernández I, Uggerud E. Nucleophilic Substitution in Reactions between Partially Hydrated Superoxide Anions and Alkyl Halides. J Org Chem 2015; 80:6133-42. [PMID: 26038972 DOI: 10.1021/acs.joc.5b00651] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effect of solvation by water molecules on the nucleophilicity of the superoxide anion, O2(•-), has been investigated in detail by mass spectrometric experiments and quantum chemical calculations, including direct dynamics trajectory calculations. Specifically, the SN2 reactions of O2(•-)(H2O)n clusters (n = 0-5) with CH3Cl and CH3Br were studied. It was found that the reaction rate decreases when the number of water molecules in the cluster increases; furthermore, reaction with CH3Br is in general faster than reaction with CH3Cl for clusters of the same size. In addition, key transition-state geometries were identified and probed by Born-Oppenheimer molecular dynamics, showing how a water molecule may be transferred from the nucleophile to the leaving group during the reaction. The computational models are in good agreement with the experimental observations.
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Affiliation(s)
- Mauritz J Ryding
- †Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, NO-0315 Oslo, Norway
| | - Andrea Debnárová
- †Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, NO-0315 Oslo, Norway
| | - Israel Fernández
- ‡Departamento de Química Orgánica I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Einar Uggerud
- †Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, NO-0315 Oslo, Norway
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17
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Ervens B. Modeling the processing of aerosol and trace gases in clouds and fogs. Chem Rev 2015; 115:4157-98. [PMID: 25898144 DOI: 10.1021/cr5005887] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Barbara Ervens
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80302, United States.,Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, Colorado 80305, United States
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18
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Al-Abadleh HA. Review of the bulk and surface chemistry of iron in atmospherically relevant systems containing humic-like substances. RSC Adv 2015. [DOI: 10.1039/c5ra03132j] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The current state of knowledge and future research directions of the bulk and surface chemistry of iron relevant to atmospheric surfaces are reviewed.
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Affiliation(s)
- Hind A. Al-Abadleh
- Department of Chemistry and Biochemistry
- Wilfrid Laurier University
- Waterloo
- Canada
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19
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Djouider F, Hussain A. A laboratory study of the oxidation of non toxic Cr(III) to toxic Cr(VI) by OH(•) free radicals in simulated atmospheric water droplets conditions: potential environmental impact. JOURNAL OF HAZARDOUS MATERIALS 2014; 276:19-25. [PMID: 24862466 DOI: 10.1016/j.jhazmat.2014.05.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 04/10/2014] [Accepted: 05/04/2014] [Indexed: 06/03/2023]
Abstract
In atmospheric waters, oxidation of Cr(III) to Cr(VI) by OH(•) free radicals is a major environmental hazard since non-toxic species is transformed into toxic one. It is important to obtain some details concerning this oxidation reaction. In this study we simulated this oxidation by steady state radiolysis using (60)Co radioactive source and pulse radiolysis technique using a 2.5MeV van de Graaff electron accelerator and investigated its kinetics in the pH range 1 to 9. Our findings showed that the reaction was highly pH dependant with a maximum yield at pH 4. The electron transfer proceeds via an inner sphere mechanism with (i) formation of the [OH(•)-Cr(III)] adduct with an equilibrium constant of 2.34×10(4)mol(-1)dm(-3) then (ii) followed by an electron transfer from Cr(III) to OH(•) within the adduct with a rate constant of 2.51×10(4)s(-1). The implication of this oxidation to atmospheric chromium contamination is discussed.
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Affiliation(s)
- Fathi Djouider
- Nuclear Engineering Department, Faculty of Engineering, King Abdulaziz University, PO Box 80204, Jeddah 21589, Saudi Arabia.
| | - Ahmad Hussain
- Nuclear Engineering Department, Faculty of Engineering, King Abdulaziz University, PO Box 80204, Jeddah 21589, Saudi Arabia
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20
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Weller C, Tilgner A, Bräuer P, Herrmann H. Modeling the impact of iron-carboxylate photochemistry on radical budget and carboxylate degradation in cloud droplets and particles. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:5652-5659. [PMID: 24678692 DOI: 10.1021/es4056643] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
To quantify the effects of an advanced iron photochemistry scheme, the chemical aqueous-phase radical mechanism (CAPRAM 3.0i) has been updated with several new Fe(III)-carboxylate complex photolysis reactions. Newly introduced ligands are malonate, succinate, tartrate, tartronate, pyruvate, and glyoxalate. Model simulations show that more than 50% of the total Fe(III) is coordinated by oxalate and up to 20% of total Fe(III) is bound in the newly implemented 1:1 complexes with tartronate, malonate, and pyruvate. Up to 20% of the total Fe(III) is found in hydroxo and sulfato complexes. The fraction of [Fe(oxalate)2](-) and [Fe(pyruvate)](2+) is significantly higher during nighttime than during daytime, which points toward a strong influence of photochemistry on these species. Fe(III) complex photolysis is an important additional sink for tartronate, pyruvate, and oxalate, with a complex photolysis contribution to overall degradation of 46, 40, and 99%, respectively, compared to all possible sink reactions with atmospheric aqueous-phase radicals, such as (•)OH, NO3(•), and SO4(•) (-). Simulated aerosol particles have a much lower liquid water content than cloud droplets, thus leading to high concentrations of species and, consequently, an enhancement of the photolysis sink reactions in the aerosol particles. The simulations showed that Fe(III) photochemistry should not be neglected when considering the fate of carboxylic acids, which constitute a major part of aqueous secondary organic aerosol (aqSOA) in tropospheric cloud droplets and aqueous particles. Failure to consider this loss pathway has the potential to result in a significant overestimate of aqSOA production.
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Affiliation(s)
- Christian Weller
- Leibniz-Institut für Troposphärenforschung , Permoserstraße 15, 04318 Leipzig, Germany
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21
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Robertson EJ, Beaman DK, Richmond GL. Designated drivers: the differing roles of divalent metal ions in surfactant adsorption at the oil-water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:15511-15520. [PMID: 24266707 DOI: 10.1021/la403665n] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Divalent metal ions play numerous roles in biological, technological, and environmental systems. This study examines the role of a variety of ions, Mg(2+), Ca(2+), Mn(2+), Ni(2+), Cu(2+), and Zn(2+), in the adsorption of sodium decanoate at the carbon tetrachloride-water interface. For all ions studied, the ions drive the adsorption of the surfactant to the interface. Using vibrational sum-frequency spectroscopy and the carboxylic acid vibrational modes as a signature for metal ion binding, each metal salt is found to play a distinctly different role in the molecular characteristics of surfactant adsorption at the interface. Additional spectroscopic studies of the methyl and methylene vibrations are monitored to track the ordering of the alkyl chains when metal salts are added to solution. How the metal-surfactant binding impacts the surfactant structure, orientation, and solvation is explored. How these spectroscopic measurements compare with the degree of adsorption as measured by interfacial tension data is presented.
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Affiliation(s)
- Ellen J Robertson
- Department of Chemistry, University of Oregon , Eugene, Oregon 97403, United States
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22
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Erel Y, Pehkonen SO, Hoffmann MR. Redox chemistry of iron in fog and stratus clouds. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jd01575] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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23
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Zhu X, Prospero JM, Savoie DL, Millero FJ, Zika RG, Saltzman ES. Photoreduction of iron(III) in marine mineral aerosol solutions. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jd00202] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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24
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Cheize M, Sarthou G, Croot PL, Bucciarelli E, Baudoux AC, Baker AR. Iron organic speciation determination in rainwater using cathodic stripping voltammetry. Anal Chim Acta 2012; 736:45-54. [PMID: 22769004 DOI: 10.1016/j.aca.2012.05.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 04/10/2012] [Accepted: 05/10/2012] [Indexed: 11/28/2022]
Abstract
A sensitive method using Competitive Ligand Exchange-Adsorptive Cathodic Stripping Voltammetry (CLE-ACSV) has been developed to determine for the first time iron (Fe) organic speciation in rainwater over the typical natural range of pH. We have adapted techniques previously developed in other natural waters to rainwater samples, using the competing ligand 1-nitroso-2-naphthol (NN). The blank was equal to 0.17±0.05 nM (n=14) and the detection limit (DL) for labile Fe was 0.15 nM which is 10-70 times lower than that of previously published methods. The conditional stability constant for NN under rainwater conditions was calibrated over the pH range 5.52-6.20 through competition with ethylenediaminetetraacetic acid (EDTA). The calculated value of the logarithm of β'(Fe(3+)(NN)(3)) increased linearly with increasing pH according to log β'(Fe(3+)(NN)(3)) (salinity=2.9, T=20 °C). The validation of the method was carried out using desferrioxamine mesylate B (DFOB) as a natural model ligand for Fe. Adequate detection windows were defined to detect this class of ligands in rainwater with 40 μM of NN from pH 5.52 to 6.20. The concentration of Fe-complexing natural ligands was determined for the first time in three unfiltered and one filtered rainwater samples. Organic Fe-complexing ligand concentrations varied from 104.2±4.1 nM equivalent of Fe(III) to 336.2±19.0 nM equivalent of Fe(III) and the logarithm of the conditional stability constants, with respect to Fe(3+), varied from 21.1±0.2 to 22.8±0.3. This method will provide important data for improving our understanding of the role of wet deposition in the biogeochemical cycling of iron.
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Affiliation(s)
- Marie Cheize
- Université Européenne de Bretagne, Rennes, France.
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25
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Zuo Y, Hoigné J. Evidence for Photochemical Formation of H2O2 and Oxidation of SO2 in Authentic Fog Water. Science 2010; 260:71-3. [PMID: 17793535 DOI: 10.1126/science.260.5104.71] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
When samples of rain and fog water were exposed to ultraviolet and visible light, reactive transients such as hydrogen peroxide were formed and dissolved organic matter and sulfur dioxide were depleted. These results, in conjunction with those from previous studies, imply that dissolved organic compounds and transition metals such as iron ions are involved in the photochemical formation of hydrogen peroxide and other photooxidants in atmospheric waters.
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26
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van Eldik R, Coichev N, Bal Reddy K, Gerhard A. Metal Ion Catalyzed Autoxidation of Sulfur(IV)-Oxides: Redox Cycling of Metal Ions Induced by Sulfite. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19920960348] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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27
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Wang Z, Huang L, Du L, Su J, Sheng H, Lv B. PHOTOCATALYSIS BY IRON-RICH MONTMORILLONITE FOR THE TREATMENT OF DYEING WASTEWATER. CHEM ENG COMMUN 2010. [DOI: 10.1080/00986440903359434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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28
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Migliavacca DM, Teixeira EC, Gervasoni F, Conceição RV, Rodriguez MTR. Characterization of wet precipitation by X-ray diffraction (XRD) and scanning electron microscopy (SEM) in the metropolitan area of Porto Alegre, Brazil. JOURNAL OF HAZARDOUS MATERIALS 2009; 171:230-240. [PMID: 19559525 DOI: 10.1016/j.jhazmat.2009.05.135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 05/27/2009] [Accepted: 05/28/2009] [Indexed: 05/28/2023]
Abstract
The purpose of this study is to assess the composition of wet precipitation in three sites of the metropolitan area of Porto Alegre. Besides the variables usually considered, such as pH, conductivity, major ions (Cl(-), NO(3)(-), F(-), SO(4)(2-), Na(+), K(+), Mg(2+), NH(4)(+) and Ca(2+)) and metallic elements (Cd, Co, Cr, Cu, Fe, Mn and Ni), the suspended matter was examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM), with energy dispersive system (EDS), for better identification of possible anthropogenic material in this wet precipitation. Results showed an alkaline pH in the samples analyzed and higher concentrations for Na(+), Cl(-) and SO(4)(2-). The acidification and neutralization potential between anions (SO(4)(2-)+NO(3)(-)) and cations (Ca(2+)+Mg(2+)+K(+)+NH(4)(+)) showed a good correlation (0.922). The metallic elements with highest values were Zn, Fe and Mn. Results of XRD identified the presence of some minerals such as quartz, feldspar, mica, clay, carbonates and sulfates. In samples analyzed with SEM, we detected pyroxene, biotite, amphibole and oxides. Cluster analysis (CA) was applied to the data matrix to identify potential pollution sources of metals (natural or anthropogenic) and the association with minerals found in the analysis of SEM.
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Affiliation(s)
- Daniela Montanari Migliavacca
- Instituto de Biociências, Programa de Pós-Graduação em Ecologia, Universidade Federal do Rio Grande do Sul, 91509-900 Porto Alegre, RS, Brazil
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29
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Ghio AJ, Dailey LA, Richards JH, Jang M. Acid and organic aerosol coatings on magnetic nanoparticles increase iron concentrations in human airway epithelial cells. Inhal Toxicol 2009; 21:659-67. [DOI: 10.1080/08958370802406282] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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30
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Alexander B, Park RJ, Jacob DJ, Gong S. Transition metal-catalyzed oxidation of atmospheric sulfur: Global implications for the sulfur budget. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jd010486] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Ghio AJ, Cohen MD. Disruption of Iron Homeostasis as a Mechanism of Biologic Effect by Ambient Air Pollution Particles. Inhal Toxicol 2008; 17:709-16. [PMID: 16195206 DOI: 10.1080/08958370500224482] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Several features of the clinical presentation and changes in physiology and pathology following exposure to many diverse ambient air pollution particles are comparable, suggesting a common mechanism for their biological effect. We propose that a mechanism of biological effect common to many ambient air pollution particles is a disruption of iron homeostasis in cells and tissues. Among traits shared by every particle-related lung injury is the introduction of a solid-liquid interface into the respiratory tract. All surfaces of particulate matter have some concentration of oxygen-containing functional groups. As a result of its electropositivity, Fe(3+) has a high affinity for oxygen-donor ligands and will react with these groups at the particle surface. Retained particles accumulate metal from available sources in a cell and tissue, and this complexed iron mediates oxidant generation. In addition to complexation onto the solid-liquid interface provided by the surface of particulate matter (PM), there are several alternative pathways by which metal homeostasis in the lower respiratory tract can be disrupted following exposure to ambient air pollution particles to affect an oxidative stress. Evidence suggests that disruption in iron homeostasis following exposures to ambient air pollution particles is an initial event in their biological effect. An association between metal equilibrium in the lower respiratory tract and biological effect in the lung could explain the observed differential toxicity of ultrafine, fine, and coarse particles and disparities in host susceptibility.
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Affiliation(s)
- Andrew J Ghio
- Clinical Research Branch, Human Studies Division, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27599, USA.
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32
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Pritchard RJ, Ghio AJ, Lehmann JR, Winsett DW, Tepper JS, Park P, Gilmour MI, Dreher KL, Costa DL. Oxidant Generation and Lung Injury after Particulate Air Pollutant Exposure Increase with the Concentrations of Associated Metals. Inhal Toxicol 2008. [DOI: 10.3109/08958379609005440] [Citation(s) in RCA: 172] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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33
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Affiliation(s)
- Dave T. F. Kuo
- a Department of Chemical Engineering and Applied Chemistry , University of Toronto , 200 College Street, Toronto, Ontario, Canada
| | - Donald W. Kirk
- a Department of Chemical Engineering and Applied Chemistry , University of Toronto , 200 College Street, Toronto, Ontario, Canada
| | - Charles Q. Jia
- a Department of Chemical Engineering and Applied Chemistry , University of Toronto , 200 College Street, Toronto, Ontario, Canada
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34
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Okada K, Kuroki Y, Nakama Y, Arakaki T, Tanahara A. Wavelength dependence of Fe(ll) photoformation in the water-soluble fraction of aerosols collected in Okinawa, Japan. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2006; 40:7790-5. [PMID: 17256529 DOI: 10.1021/es061649s] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We studied photoformation of Fe(II) in the water-soluble fractions (WSFs) of bulk aerosol particles collected in Okinawa, Japan, using radiation at wavelengths of 313, 334, 366, and 405 nm. Fe(II) photoformation quickly reached a steady state within 5 min of irradiation at all wavelengths. The steady-state Fe(II) concentrations were 85+/-13% (n = 39) of the total dissolved Fe (TDFe) concentrations in the WSF solutions. Apparent quantum yields of Fe(II) photoformation were determined based on total absorbance of the WSF solutions, and the means (+/-1 S.D.) were 0.019 (+/-0.034), 0.021 (+/-0.031), 0.014 (+/-0.023), and 0.010 (+/-0.025) at 313, 334, 366, and 405 nm, respectively. Comparison of the observed rates of Fe(II) photoformation for the WSF solutions and the calculated rates from the known Fe(II)-forming compounds suggested that Fe(oxalate)2- could account for the observed Fe(II) photoformation rates if the Fe(oxalate)2- concentration is sufficiently high (>20% of [Fe(III)]o). Furthermore, our study showed that the calculated wavelength dependence of Fe(ll) photoformation from Fe(oxalate)2- was consistent with that of Fe(II) photoformation observed in the WSF solutions. The results obtained here have implications to daytime Fe(III)/ Fe(II) cycles in the atmospheric water droplet.
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Affiliation(s)
- Kouichirou Okada
- Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru Nishihara-cho, Okinawa 903-0213, Japan
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35
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36
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Wang L, Zhang C, Wu F, Deng N. Photoproduction and determination of hydroxyl radicals in aqueous solutions of Fe(III)–tartrate complexes: a quantitative assessment. J COORD CHEM 2006. [DOI: 10.1080/00958970500404641] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Lei Wang
- a Department of Environmental Science , Wuhan University , Wuhan 430 72, P.R. China
| | - Changbo Zhang
- a Department of Environmental Science , Wuhan University , Wuhan 430 72, P.R. China
| | - Feng Wu
- a Department of Environmental Science , Wuhan University , Wuhan 430 72, P.R. China
| | - Nansheng Deng
- a Department of Environmental Science , Wuhan University , Wuhan 430 72, P.R. China
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37
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Mancinelli V, Decesari S, Facchini MC, Fuzzi S, Mangani F. Partitioning of metals between the aqueous phase and suspended insoluble material in fog droplets. ACTA ACUST UNITED AC 2006; 95:275-90. [PMID: 16477936 DOI: 10.1002/adic.200590033] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This paper discusses the partitioning of metals (K, Na, Ca, Mg, Al, Cu, Fe, Pb and Zn) between the aqueous phase and the suspended insoluble material in fog samples collected in the Po Valley during two extensive fields campaigns. Metals represent on average 11% of the mass of suspended insoluble matter, while the main component is carbon (both organic carbon, OC = 35%, and black carbon, BC = 8%). The unaccounted suspended matter mass is very high, on average 46%, and is attributable to non metallic species, such as O and N and of Si. The principal metals in the insoluble suspended fraction are Fe and Al (2-5%), while the contributions of other metals (Na, Mg, Cu, Pb and Zn) are lower than 1%. Ca and K exhibited high blank values and could not be detected above blank detection limit threshold. The main components in the aqueous phase are NO3- (34%), WSOC (23%), SO4(2-) (18%) and NH4+ (19%), while trace metals and remaining cations and anions accounted for less than 1% of solute mass. The main dissolved trace metals in fog droplets are Zn, Al and Fe, while the main metallic cations are Na and Ca. Fe and Al are the only metals preferentially distributed in the suspended insoluble matter of fog droplets (partitioning ratio respectively 37% and 33%). All other metals are mostly dissolved in the aqueous phase (mean partitioning ratios of Mg, Pb, Zn, Cu and Na are 69%, 70%, 77%, 81% and 87%). These findings are in agreement with literature data on metal speciation in cloud and rain samples. The dependence of partitioning ratios on pH is investigated for the different metals, with only Al showing a clear partitioning ratio decrease with increasing pH. Conversely, the other metals show no dependence or a complex and highly variable behaviour. The partitioning ratio of iron (mean 37%) observed in the Po Valley fog samples is much higher than the water extractable iron in aerosol particles (typically 1-2 %): this fact can be explained by differences in the aerosol sources and composition among sites and by chemical processes in the aqueous phase, such as complexation and redox reactions involving organic ligands (oxalate, or other organic acids as humic-like organic matter) which may promote Fe solubility.
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Affiliation(s)
- Valeriana Mancinelli
- Facoltà di Scienze Ambientali, Università degli studi di Urbino, Campus Scientifico ex Sogesta località Crocicchia, 61029 Urbino, Italy
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Garrel L, Bonetti M, Tonucci L, d’Alessandro N, Bressan M. Photosensitized degradation of cyclohexanol by Fe(III) species in alkaline aqueous media. J Photochem Photobiol A Chem 2006. [DOI: 10.1016/j.jphotochem.2005.08.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Deguillaume L, Leriche M, Desboeufs K, Mailhot G, George C, Chaumerliac N. Transition metals in atmospheric liquid phases: sources, reactivity, and sensitive parameters. Chem Rev 2005; 105:3388-431. [PMID: 16159157 DOI: 10.1021/cr040649c] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Laurent Deguillaume
- Laboratoire de Météorologie Physique, Centre National de la Recherche Scientifique, Université Blaise Pascal, 24 avenue des Landais, 63177 Aubière Cedex, France.
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Lee C, Yoon J. Determination of quantum yields for the photolysis of Fe(III)-hydroxo complexes in aqueous solution using a novel kinetic method. CHEMOSPHERE 2004; 57:1449-1458. [PMID: 15519389 DOI: 10.1016/j.chemosphere.2004.07.052] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2003] [Revised: 07/09/2004] [Accepted: 07/21/2004] [Indexed: 05/24/2023]
Abstract
The determination of quantum yields for the photolysis of Fe(III)-hydroxo complexes is important for the quantitative investigation of hydroxyl radical (*OH) production, not only in a natural water body, but also in the photo-Fenton process. A novel kinetic method, using a *OH probe compound, was established for the determination of the quantum yields in this study. The method was based on measuring the pseudo-first-order rate constant of the photodecomposition of dimethylsulfoxide (DMSO) in which DMSO and its primary products scavenged the *OH at an identical rate. The preliminary experiments for the photodecomposition kinetics supported the suitability of DMSOs as a probe compound for determining quantum yields. The individual quantum yields for the photolysis of the monomeric Fe(III) complexes, in the wavelength range 240-380 nm, were determined by the photodecomposition kinetics of the hydroxyl radical (*OH) probe compound (DMSO). The determined values of the individual quantum yields were 0.046+/-0.00052 for Fe3+ (H2O)6 (hexaaquo ion) and 0.69+/-0.025 for Fe(OH)2+ (H2O)5 (hydroxypentaaquo ion) at 254 nm, and showed decreasing values with increasing wavelength, in the ranges of 240-380 nm. The quantum yields between 240 and 280 nm were newly reported in this study, and the values obtained between 280 and 380 nm were in good agreement with the literature values.
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Affiliation(s)
- Changha Lee
- School of Chemical Engineering, College of Engineering, Seoul National University, San 56-1, Shilim-dong, Gwanak-gu, Seoul 151-742, South Korea
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Gao Y. Aeolian iron input to the ocean through precipitation scavenging: A modeling perspective and its implication for natural iron fertilization in the ocean. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002jd002420] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Horváth O, Huszánk R. Degradation of surfactants by hydroxyl radicals photogenerated from hydroxoiron(iii) complexes. Photochem Photobiol Sci 2003; 2:960-6. [PMID: 14560815 DOI: 10.1039/b303697a] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Fe(III)-photoinduced oxidation of anionic lauryl sulfate (LS-) and cationic cetyltrimethylammonium (CTA+) surfactants has been investigated in aqueous solution. Competition experiments using 2-propanol showed that the initial rate of disappearance is proportional to the concentration of the photogenerated HO* radicals scavenged by the surfactants (the degradation of lauryl sulfate involves attack by HO* only) and no direct photoinduced charge-transfer reaction occurs between the Fe(III) species and the surfactant ions. Ageing of the Fe(III) solution did not significantly influence the efficiency of photodegradation in air-saturated systems. Conversion of Fe(III) to Fe(II) in aerated solution reached a steady-state level of ca. 50% after 2 h irradiation. In nitrogen-saturated systems, the rate of surfactant oxidation decreased due to the total reduction of Fe(III). Addition of H2O2 doubled the quantum yield of the disappearance of both detergents as a result of the photo-Fenton reaction. The photoinduced oxidation of both surfactants was most efficient in acidic solutions of pH 2-3, without H2O2, and for the photo-Fenton system; the quantum yields are phi(NaLS) = 0.011, phi(CTAB) = 0.012 without H2O2, and phi(NaLS) = 0.024, phi(CTAB) = 0.027 in the photo-Fenton system with irradiation at 366 nm. For the disappearance of 4 x 10(-4) M detergent, due to the first oxidation step, 4 h of irradiation (at pH 2.6) is sufficient, whereas 100% mineralization of the total organic carbon content requires prolonged photolysis for at least 10 h. The formation of carbon dioxide dramatically accelerated after a 2 h induction period (1 h in the photo-Fenton system), indicating the cleavage of the long hydrocarbon chains to shorter intermediates in the first stage of the mechanism. The following step is total mineralization of these smaller compounds, which were identified as mostly hydroxy acids via GC-MS.
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Affiliation(s)
- Ottó Horváth
- Department of General and Inorganic Chemistry, University of Veszprém, P. O. B. 158, H-8200 Veszprém, Hungary.
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Andreozzi R, D'Apuzzo A, Marotta R. A kinetic model for the degradation of benzothiazole by Fe3+-photo-assisted Fenton process in a completely mixed batch reactor. JOURNAL OF HAZARDOUS MATERIALS 2000; 80:241-257. [PMID: 11080581 DOI: 10.1016/s0304-3894(00)00308-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The degradation of benzothiazole in aqueous solution by a photo-assisted Fenton reaction has been studied in a batch reactor in the pH range 2.0 - 3.2 and for H2O2 and Fe(III) concentrations respectively between 1.0 x 10(-3) - 1.5 x 10(-1) and 1.0 x 10(-6) - 4.0 x 10(-6) M. A kinetic model has been developed to predict the decay of benzothiazole at varying reaction conditions. The use of kinetic constants from the literature in the model allows to simulate the system behavior by taking into account the influence of pH, hydrogen peroxide, Fe(III) and sulfate concentrations and the ionic strength.
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Affiliation(s)
- R Andreozzi
- Dipartimento di Ingegneria Chimica, Facoltà di Ingegneria, Università di Napoli "Federico II", p.le V. Tecchio, 80125, Napoli, Italy.
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Feng W, Nansheng D. Photochemistry of hydrolytic iron (III) species and photoinduced degradation of organic compounds. A minireview. CHEMOSPHERE 2000; 41:1137-1147. [PMID: 10901238 DOI: 10.1016/s0045-6535(00)00024-2] [Citation(s) in RCA: 219] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
On the basis of the research literature of the last fifty years, we have reviewed the photochemical properties of different hydrolytic Fe(III) species and the photodegradation of organic compounds in aqueous solutions initiated by them (mainly including low-molecular-weight Fe(III)-OH complexes, Fe(III) oxides (Fe2O3) and Fe(III) hydroxides (FeOOH)). Furthermore, the feasibility and prospects of the novel photochemical methods of using Fe(III) salts and oxides in wastewater treatments are being discussed in this paper.
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Affiliation(s)
- W Feng
- Department of Environmental Science and Engineering, Wuhan University, Hubei, People's Republic of China.
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Desboeufs KV, Losno R, Vimeux F, Cholbi S. The pH-dependent dissolution of wind-transported Saharan dust. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999jd900236] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Ghio AJ, Stoneheurner J, McGee JK, Kinsey JS. Sulfate content correlates with iron concentrations in ambient air pollution particles. Inhal Toxicol 1999; 11:293-307. [PMID: 10380171 DOI: 10.1080/089583799197104] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Current levels of air pollution particles in American cities can increase human mortality. Both the mechanism of injury and the responsible components are not known. We have postulated that injury following air pollution particle exposure is produced through a generation of oxygen-based free radicals catalyzed by metals present in the particles. As a result of its abundance in the atmosphere, sulfate appears to potentially be the most successful ligand to complex metal cations. We tested the hypothesis that (1) some portion of iron in ambient air pollution particles is present as sulfate and (2) this relationship between iron and sulfate results from the capacity of the latter to function as a ligand to mobilize the metal from the oxide. Concentrations of sulfate and iron in acid extracts of 20 filters (total suspended particles) from Utah were measured using inductively coupled plasma emission spectroscopy. In vitro oxidant generation was also measured using thiobarbituric acid-reactive products of deoxyribose. There were significant correlations between sulfate content, iron concentrations, and oxidant generation. Agitation of calcium sulfate with iron(III) oxide produced concentrations of water-soluble, catalytically active iron. We conclude that some portion of iron in the atmosphere is present as a sulfate. This relationship between sulfate and iron concentrations is likely the product of SO42- functioning as a ligand for the meal after its mobilization from an oxide by photoreduction. There were also associations between sulfate content, iron concentrations, and oxidant generation. However, sulfates had no capacity to support electron transport unless they were present with iron.
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Affiliation(s)
- A J Ghio
- National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Clinical Research Branch, Human Studies Division, Research Triangle Park, NC 27711, USA
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Siefert RL, Johansen AM, Hoffmann MR. Chemical characterization of ambient aerosol collected during the southwest monsoon and intermonsoon seasons over the Arabian Sea: Labile-Fe(II) and other trace metals. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1998jd100067] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Phototransformations Induced in Aquatic Media by NO 3 - /NO 2 - , FeIII and Humic Substances. ACTA ACUST UNITED AC 1999. [DOI: 10.1007/978-3-540-69044-3_7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Ghio AJ, Stonehuerner J, Dailey LA, Carter JD. Metals associated with both the water-soluble and insoluble fractions of an ambient air pollution particle catalyze an oxidative stress. Inhal Toxicol 1999; 11:37-49. [PMID: 10380158 DOI: 10.1080/089583799197258] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
One potential mechanism of injury mediated by air pollution particles is through metal-catalyzed oxidant generation. In one emission source particle, soluble metals have been associated with biological effect and toxicity. However, a majority of metals in ambient air pollution particles can be associated with insoluble components. We tested the hypothesis that concentrations of catalytically active metal in ambient air pollution particles are not equivalent to the concentrations of water-soluble metal. Twelve filters collected from the North Provo, UT, monitoring station were agitated in deionized water. Both the aqueous extract and pellet were isolated, lyophilized, and defined as the water-soluble and insoluble fractions, respectively. The fractions were chemically characterized and ionizable concentrations of metals were measured using inductively coupled plasma emission spectroscopy. While the water-soluble fraction had significantly greater concentrations of ionizable metals per unit mass, the insoluble fraction also had measurable quantities. In vitro oxidant generation by the two fractions, measured as thiobarbituric acid-reactive-products of deoxyribose, corresponded to the concentrations of ionizable rather than total metals. The release of interleukin-8 by cultured respiratory epithelial cells after incubation with the two fractions also coincided with the ionizable metal concentrations. Finally, neutrophil influx and lavage protein levels 24 h after instillation of the two fractions in rats reflected the ionizable metal concentrations, in vitro oxidative stress, and mediator release. We conclude that catalytically active metals can be measured in both the soluble and insoluble fractions of an ambient air pollution particle. These metals corresponded to the biological activity of the two fractions. While in greater concentration in the water-soluble fraction, larger total quantities of catalytically and biologically active metals are likely to be associated with the insoluble fraction as a result of the abundance of the latter.
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Affiliation(s)
- A J Ghio
- CRB, HSD, National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, 104 Mason Farm Road, Chapel Hill, NC 27599, USA
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