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Lambert S, Vercauteren M, Catarino AI, Li Y, Van Landuyt J, Boon N, Everaert G, De Rijcke M, Janssen CR, Asselman J. Aerosolization of micro- and nanoplastics via sea spray: Investigating the role of polymer type, size, and concentration, and potential implications for human exposure. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 351:124105. [PMID: 38710359 DOI: 10.1016/j.envpol.2024.124105] [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: 01/18/2024] [Revised: 04/11/2024] [Accepted: 05/02/2024] [Indexed: 05/08/2024]
Abstract
Micro- and nanoplastics (MNPs) can enter the atmosphere via sea spray aerosols (SSAs), but the effects of plastic characteristics on the aerosolization process are unclear. Furthermore, the importance of the transport of MNPs via these SSAs as a possible new exposure route for human health remains unknown. The aim of this study was two-fold: (1) to examine if a selection of factors affects aerosolization processes of MNPs, and (2) to estimate human exposure to MNPs via aerosols inhalation. A laboratory-based bubble bursting mechanism, simulating the aerosolization process at sea, was used to investigate the influence of MNP as well as seawater characteristics. To determine the potential human exposure to microplastics via inhalation of SSAs, the results of the laboratory experiments were extrapolated to the field based on sea surface microplastic concentrations and the volume of inhaled aerosols. Enrichment seemed to be influenced by MNP size, concentration and polymer type. With higher enrichment for smaller particles and denser polymers. Experiments with different concentrations showed a larger range of variability but nonetheless lower concentrations seemed to result in higher enrichment, presumably due to lower aggregation. In addition to the MNP characteristics, the type of seawater used seemed to influence the aerosolization process. Our human exposure estimate to microplastic via inhalation of sea spray aerosols shows that in comparison with reported inhaled concentrations in urban and indoor environments, this exposure route seems negligible for microplastics. Following the business-as-usual scenario on plastic production, the daily plastic inhalation in coastal areas in 2100 is estimated to increase but remain far below 1 particle per day. This study shows that aerosolization of MNPs is a new plastic transport pathway to be considered, but in terms of human exposure it seems negligible compared to other more important sources of MNPs, based on current reported environmental concentrations.
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Affiliation(s)
- Silke Lambert
- Blue Growth Research Lab, Ghent University, Bluebridge, Wetenschapspark 1, 8400, Oostende, Belgium.
| | - Maaike Vercauteren
- Blue Growth Research Lab, Ghent University, Bluebridge, Wetenschapspark 1, 8400, Oostende, Belgium.
| | - Ana Isabel Catarino
- Flanders Marine Institute (VLIZ), Research Department Ocean and Human Health, InnovOcean Campus, Jacobsenstraat 1, 8400, Oostende, Belgium.
| | - Yunmeng Li
- Blue Growth Research Lab, Ghent University, Bluebridge, Wetenschapspark 1, 8400, Oostende, Belgium; Flanders Marine Institute (VLIZ), Research Department Ocean and Human Health, InnovOcean Campus, Jacobsenstraat 1, 8400, Oostende, Belgium.
| | - Josefien Van Landuyt
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
| | - Nico Boon
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
| | - Gert Everaert
- Flanders Marine Institute (VLIZ), Research Department Ocean and Human Health, InnovOcean Campus, Jacobsenstraat 1, 8400, Oostende, Belgium.
| | - Maarten De Rijcke
- Flanders Marine Institute (VLIZ), Research Department Ocean and Human Health, InnovOcean Campus, Jacobsenstraat 1, 8400, Oostende, Belgium.
| | - Colin R Janssen
- Blue Growth Research Lab, Ghent University, Bluebridge, Wetenschapspark 1, 8400, Oostende, Belgium; Ghent University Environmental Toxicology Lab (Ghentoxlab), Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
| | - Jana Asselman
- Blue Growth Research Lab, Ghent University, Bluebridge, Wetenschapspark 1, 8400, Oostende, Belgium.
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Xu M, Tchinda NT, Li S, Du L. Enhanced saccharide enrichment in sea spray aerosols by coupling surface-active fatty acids. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170322. [PMID: 38278262 DOI: 10.1016/j.scitotenv.2024.170322] [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: 11/14/2023] [Revised: 12/27/2023] [Accepted: 01/18/2024] [Indexed: 01/28/2024]
Abstract
The chemical composition of aerosols plays a significant role in aerosol-cloud interactions and, although saccharides make up their largest organic mass fraction, the current process model for understanding sea spray aerosol (SSA) composition struggles to replicate the enrichment of saccharides that has been observed. Here, we simulated the generation of SSA and quantified the enrichment of two soluble saccharides (glucose and trehalose) in SSA with a homemade sea spray aerosol generator. The results of the generation experiments demonstrated that both saccharides, especially trehalose, can promote the generation of SSA, whereas surface-active fatty acids primarily inhibit SSA production due to fewer bubble bursts caused by a large amount of foam accumulation. A significant decrease in surface tension of seawater with the addition of fatty acids was observed, while only a minor decrease was observed for seawater with the addition of only saccharide. Enrichment factors (EFs) of saccharides measured using high performance anion-exchange chromatography (HPAEC) with pulsed amperometric detection (PAD) revealed no enrichment of glucose in submicron SSA, while trehalose showed a slight enrichment. In the presence of surface-active fatty acids on the seawater surface, a significant increase in the enrichment of saccharides in SSA was observed, with glucose and trehalose showing EF of approximately 27-fold and 58-fold, respectively. Besides, this enrichment was accompanied by the accumulation of calcium and magnesium ions. The results presented here suggest that the coupling interaction mechanism of soluble saccharides and surface-active fatty acids on the ocean surface contributes to the enrichment of soluble saccharides in SSA.
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Affiliation(s)
- Minglan Xu
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao 266237, China
| | - Narcisse Tsona Tchinda
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao 266237, China
| | - Siyang Li
- Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation, School of Ecology and Environment, Hainan University, No. 58, Renmin Avenue, Haikou 570228, China
| | - Lin Du
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao 266237, China.
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3
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Song Y, Li J, Tsona NT, Liu L, Du L. Enrichment of short-chain organic acids transferred to submicron sea spray aerosols. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158122. [PMID: 35988626 DOI: 10.1016/j.scitotenv.2022.158122] [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: 05/31/2022] [Revised: 08/10/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Organic acids, considered to be a substantial component of the marine carbon cycle, can enter the atmosphere through sea spray aerosol (SSA) and further affect the climate. Despite their importance, the distribution and mixing state of organic acids in SSA over the marine boundary layer are poorly understood and therefore need more investigation. Here, we have used ion chromatography (IC) in anion mode to measure short-chain organic acids concentrations in SSA collected throughout a custom-made SSA simulation chamber. The enrichment behavior and morphology of monocarboxylic acids (MAs, C1-8) and dicarboxylic acids (DAs) in submicron SSA were studied in seawater. We found that with MAs addition, the number concentration and mass concentration of SSA particles decreased gradually for C5-8 MAs, whereas they weakly varied with DAs addition due to the fact that carboxyl groups at both ends of DAs increased the surface tension of seawater. Moreover, the target compounds in submicron SSA displayed a surface activity-dependent enrichment behavior, where seawater with stronger surface activity, such as that containing MAs with >5 carbons, was more enriched in SSA in comparison to seawater with weaker surface activity. MAs with chain length <5 carbons were slightly enriched in SSA, whereas the enrichment factor (EF) of C5-8 MAs further increased with increasing chain length. These findings are of utmost importance in further understanding and quantifying the contribution of organic matter to SSA, which is crucial for assessing the atmosphere feedback of the marine carbon cycle. MAIN FINDING OF THE WORK: Surface tension of seawater is the key factor affecting the enrichment of short-chain organic acids in SSA.
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Affiliation(s)
- Yaru Song
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Jianlong Li
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Narcisse T Tsona
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Lingrui Liu
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Lin Du
- Environment Research Institute, Shandong University, Qingdao 266237, China.
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4
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Chen S, Artiglia L, Orlando F, Edebeli J, Kong X, Yang H, Boucly A, Corral Arroyo P, Prisle N, Ammann M. Impact of Tetrabutylammonium on the Oxidation of Bromide by Ozone. ACS EARTH & SPACE CHEMISTRY 2021; 5:3008-3021. [PMID: 34825122 PMCID: PMC8607506 DOI: 10.1021/acsearthspacechem.1c00233] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 10/01/2021] [Accepted: 10/09/2021] [Indexed: 06/13/2023]
Abstract
The reaction of ozone with sea-salt derived bromide is relevant for marine boundary layer atmospheric chemistry. The oxidation of bromide by ozone is enhanced at aqueous interfaces. Ocean surface water and sea spray aerosol are enriched in organic compounds, which may also have a significant effect on this reaction at the interface. Here, we assess the surface propensity of cationic tetrabutylammonium at the aqueous liquid-vapor interface by liquid microjet X-ray photoelectron spectroscopy (XPS) and the effect of this surfactant on ozone uptake to aqueous bromide solutions. The results clearly indicate that the positively charged nitrogen group in tetrabutylammonium (TBA), along with its surface activity, leads to an enhanced interfacial concentration of both bromide and the bromide ozonide reaction intermediate. In parallel, off-line kinetic experiments for the same system demonstrate a strongly enhanced ozone loss rate in the presence of TBA, which is attributed to an enhanced surface reaction rate. We used liquid jet XPS to obtain detailed chemical composition information from the aqueous-solution-vapor interface of mixed aqueous solutions containing bromide or bromide and chloride with and without TBA surfactant. Core level spectra of Br 3d, C 1s, Cl 2p, N 1s, and O 1s were used for this comparison. A model was developed to account for the attenuation of photoelectrons by the carbon-rich layer established by the TBA surfactant. We observed that the interfacial density of bromide is increased by an order of magnitude in solutions with TBA. The salting-out of TBA in the presence of 0.55 M sodium chloride is apparent. The increased interfacial bromide density can be rationalized by the association constants for bromide and chloride to form ion-pairs with TBA. Still, the interfacial reactivity is not increasing simply proportionally with the increasing interfacial bromide concentration in response to the presence of TBA. The steady state concentration of the bromide ozonide intermediate increases by a smaller degree, and the lifetime of the intermediate is 1 order of magnitude longer in the presence of TBA. Thus, the influence of cationic surfactants on the reactivity of bromide depends on the details of the complex environment at the interface.
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Affiliation(s)
- Shuzhen Chen
- Laboratory
of Environmental Chemistry, Paul Scherrer
Institute, 5232 Villigen, Switzerland
- Institute
of Atmospheric and Climate Sciences, ETH
Zürich, 8006 Zürich, Switzerland
| | - Luca Artiglia
- Laboratory
of Environmental Chemistry, Paul Scherrer
Institute, 5232 Villigen, Switzerland
| | - Fabrizio Orlando
- Laboratory
of Environmental Chemistry, Paul Scherrer
Institute, 5232 Villigen, Switzerland
| | - Jacinta Edebeli
- Laboratory
of Environmental Chemistry, Paul Scherrer
Institute, 5232 Villigen, Switzerland
- Institute
of Atmospheric and Climate Sciences, ETH
Zürich, 8006 Zürich, Switzerland
| | - Xiangrui Kong
- Center
for Atmospheric Research, University of
Oulu, P.O. Box 4500, 90014 Oulu, Finland
| | - Huanyu Yang
- Laboratory
of Environmental Chemistry, Paul Scherrer
Institute, 5232 Villigen, Switzerland
- Institute
of Atmospheric and Climate Sciences, ETH
Zürich, 8006 Zürich, Switzerland
| | - Anthony Boucly
- Laboratory
of Environmental Chemistry, Paul Scherrer
Institute, 5232 Villigen, Switzerland
| | - Pablo Corral Arroyo
- Laboratory
of Environmental Chemistry, Paul Scherrer
Institute, 5232 Villigen, Switzerland
| | - Nønne Prisle
- Center
for Atmospheric Research, University of
Oulu, P.O. Box 4500, 90014 Oulu, Finland
| | - Markus Ammann
- Laboratory
of Environmental Chemistry, Paul Scherrer
Institute, 5232 Villigen, Switzerland
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5
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Ding Y, Zhu J, Liu D. Separation performance and mechanism of the novel modified polyether sulfone composite nanofiltration membrane for the detection on dissolved organic nitrogen. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2021; 93:1748-1761. [PMID: 33780582 DOI: 10.1002/wer.1562] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 03/05/2021] [Accepted: 03/19/2021] [Indexed: 06/12/2023]
Abstract
The most effective pretreatment method for the detection of dissolved organic nitrogen (DON) is the nanofiltration (NF) by effectively intercepting DON into the concentrated solution, thus increasing the proportion of DON in solution so that achieving accurate detection of DON. The existing NF pretreatment technology for detection of DON has the problem of low accuracy and unclear separation mechanism of mass transfer upon the NF membranes. Based on the problems of NF membrane, the polyether sulfone (PES) composite NF membrane was modified by mesoporous carbon and the basic performance parameters of the modified PES composite NF membrane were characterized by Static contact angle (SCA), Zeta potential, and X-ray photoelectron spectroscopy (XPS). The results show that the optimum doping amount of mesoporous carbon is in the range of 0.5%-1.0%. Furthermore, the pore size of NF membrane could be controlled effectively by changing doping amount of mesoporous carbon, so as to guide the improvement of membrane pore structure. After the pretreatment of mesoporous material modified PES composite NF membrane, the ratio of dissolved inorganic nitrogen (DIN)/total dissolved nitrogen (TDN) could be reduced to 0.55-0.65 and the pretreatment effect was also affected by screening effect and electrostatic effect. The best retention performance of amino acids is the 1.0%C modified membrane which retention rate of the amino acid is between 32.3% and 94.7%, and the membrane loss of the four amino acids is much smaller than other membranes. The mass transfer process of NF membrane was simulated by steric-hindrance pore (SHP) model, Teorell-Meyer-Sievers (TMS) model, and Electrostatic Steric-hindrance (ES) model respectively. According to the simulation software designed by ourselves, the dominant effects of screening and electrostatic effects are simultaneously affected by the pore structure of membranes and the size of the contaminant molecules. PRACTITIONER POINTS: The feasibility of mesoporous carbon with modified PES composite nanofiltration membrane pretreatment for DON measurement in comparison to pure NF membranes was investigated. The ability of modified PES composite NF membrane with different molecular weight of DON and the relationship between pore radius of membrane and interception pollutant molecular size was discussed. The influence of screening effect and electrostatic effect on the retention of pollutants was discussed by the SHP model, TMS model and ES model; the simulation software interface is designed and the calculation process of the model is simulated by computer.
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Affiliation(s)
- Ying Ding
- College of Environment Science, Nanjing Xiaozhuang University, Nanjing, China
| | - Jianzhong Zhu
- College of Environment, Hohai University, Nanjing, China
| | - Dong Liu
- Suzhou Erye Pharmaceutical Co., Ltd, Suzhou, China
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6
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Tinel L, Adams TJ, Hollis LDJ, Bridger AJM, Chance RJ, Ward MW, Ball SM, Carpenter LJ. Influence of the Sea Surface Microlayer on Oceanic Iodine Emissions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:13228-13237. [PMID: 32975119 PMCID: PMC7586339 DOI: 10.1021/acs.est.0c02736] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 09/23/2020] [Accepted: 09/25/2020] [Indexed: 05/26/2023]
Abstract
The influence of organic compounds on iodine (I2) emissions from the O3 + I- reaction at the sea surface was investigated in laboratory and modeling studies using artificial solutions, natural subsurface seawater (SSW), and, for the first time, samples of the surface microlayer (SML). Gas-phase I2 was measured directly above the surface of liquid samples using broadband cavity enhanced absorption spectroscopy. I2 emissions were consistently lower for artificial seawater (AS) than buffered potassium iodide (KI) solutions. Natural seawater samples showed the strongest reduction of I2 emissions compared to artificial solutions with equivalent [I-], and the reduction was more pronounced over SML than SSW. Emissions of volatile organic iodine (VOI) were highest from SML samples but remained a negligible fraction (<1%) of the total iodine flux. Therefore, reduced iodine emissions from natural seawater cannot be explained by chemical losses of I2 or hypoiodous acid (HOI), leading to VOI. An interfacial model explains this reduction by increased solubility of the I2 product in the organic-rich interfacial layer of seawater. Our results highlight the importance of using environmentally representative concentrations in studies of the O3 + I- reaction and demonstrate the influence the SML exerts on emissions of iodine and potentially other volatile species.
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Affiliation(s)
- Liselotte Tinel
- Department
of Chemistry, University of York, York YO10 5DD, U.K.
| | - Thomas J. Adams
- School
of Chemistry, University of Leicester, Leicester LE1 7RH, U.K.
- Ricardo
Energy & Environment, Harwell, Oxfordshire OX11 0QR, U.K.
| | | | | | - Rosie J. Chance
- Department
of Chemistry, University of York, York YO10 5DD, U.K.
| | - Martyn W. Ward
- Department
of Chemistry, University of York, York YO10 5DD, U.K.
| | - Stephen M. Ball
- School
of Chemistry, University of Leicester, Leicester LE1 7RH, U.K.
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7
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Li Y, Shrestha M, Luo M, Sit I, Song M, Grassian VH, Xiong W. Salting Up of Proteins at the Air/Water Interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:13815-13820. [PMID: 31584824 DOI: 10.1021/acs.langmuir.9b01901] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Vibrational sum frequency generation (VSFG) spectroscopy and surface pressure measurements are used to investigate the adsorption of a globular protein, bovine serum albumin (BSA), at the air/water interface with and without the presence of salts. We find at low (2 to 5 ppm) protein concentrations, which is relevant to environmental conditions, both VSFG and surface pressure measurements of BSA behave drastically different from at higher concentrations. Instead of emerging to the surface immediately, as observed at 1000 ppm, protein adsorption kinetics is on the order of tens of minutes at lower concentrations. Most importantly, salts strongly enhance the presence of BSA at the interface. This "salting up" effect differs from the well-known "salting out" effect as it occurs at protein concentrations well-below where "salting out" occurs. The dependence on salt concentration suggests this effect relates to a large extent electrostatic interactions and volume exclusion. Additionally, results from other proteins and the pH dependence of the kinetics indicate that salting up depends on the flexibility of proteins. This initial report demonstrates "salting up" as a new type of salt-driven interfacial phenomenon, which is worthy of continued investigation given the importance of salts in biological and environmental aqueous systems.
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8
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Zeppenfeld S, van Pinxteren M, Hartmann M, Bracher A, Stratmann F, Herrmann H. Glucose as a Potential Chemical Marker for Ice Nucleating Activity in Arctic Seawater and Melt Pond Samples. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:8747-8756. [PMID: 31248257 DOI: 10.1021/acs.est.9b01469] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Recent studies pointed to a high ice nucleating activity (INA) in the Arctic sea surface microlayer (SML). However, related chemical information is still sparse. In the present study, INA and free glucose concentrations were quantified in Arctic SML and bulk water samples from the marginal ice zone, the ice-free ocean, melt ponds, and open waters within the ice pack. T50 (defining INA) ranged from -17.4 to -26.8 °C. Glucose concentrations varied from 0.6 to 51 μg/L with highest values in the SML from the marginal ice zone and melt ponds (median 16.3 and 13.5 μg/L) and lower values in the SML from the ice pack and the ice-free ocean (median 3.9 and 4.0 μg/L). Enrichment factors between the SML and the bulk ranged from 0.4 to 17. A positive correlation was observed between free glucose concentration and INA in Arctic water samples (T50(°C) = (-25.6 ± 0.6) + (0.15 ± 0.04)·Glucose(μg/L), RP = 0.66, n = 74). Clustering water samples based on phytoplankton pigment composition resulted in robust but different correlations within the four clusters (RP between 0.67 and 0.96), indicating a strong link to phytoplankton-related processes. Since glucose did not show significant INA itself, free glucose may serve as a potential tracer for INA in Arctic water samples.
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Affiliation(s)
| | | | | | - Astrid Bracher
- Alfred-Wegener-Institute Helmholtz Centre for Polar and Marine Research , Bremerhaven , Germany
- Institute of Environmental Physics , University of Bremen , Bremen , Germany
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9
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The Impact of Divalent Cations on the Enrichment of Soluble Saccharides in Primary Sea Spray Aerosol. ATMOSPHERE 2018. [DOI: 10.3390/atmos9120476] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Field measurements have shown that sub-micrometer sea spray aerosol (SSA) is significantly enriched in organic material, of which a large fraction has been attributed to soluble saccharides. Existing mechanistic models of SSA production struggle to replicate the observed enhancement of soluble organic material. Here, we assess the role for divalent cation mediated co-adsorption of charged surfactants and saccharides in the enrichment of soluble organic material in SSA. Using measurements of particle supersaturated hygroscopicity, we calculate organic volume fractions for molecular mimics of SSA generated from a Marine Aerosol Reference Tank. Large enhancements in SSA organic volume fractions (Xorg > 0.2) were observed for 50 nm dry diameter (dp) particles in experiments where cooperative ionic interactions were favorable (e.g., palmitic acid, Mg2+, and glucuronic acid) at seawater total organic carbon concentrations (<1.15 mM C) and ocean pH. Significantly smaller SSA organic volume fractions (Xorg < 1.5 × 10−3) were derived from direct measurements of soluble saccharide concentrations in collected SSA with dry diameters <250 nm, suggesting that organic enrichment is strongly size dependent. The results presented here indicate that divalent cation mediated co-adsorption of soluble organics to insoluble surfactants at the ocean surface may contribute to the enrichment of soluble saccharides in SSA. The extent to which this mechanism explains the observed enhancement of saccharides in nascent SSA depends strongly on the concentration, speciation, and charge of surfactants and saccharides in the sea surface microlayer.
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10
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Pagliano E, Campanella B, Shi L, Thibeault MP, Onor M, Crum S, Melanson JE, Mester Z. Determination of total dissolved nitrogen in seawater by isotope dilution gas chromatography mass spectrometry following digestion with persulfate and derivatization with aqueous triethyloxonium. J Chromatogr A 2018; 1569:193-199. [PMID: 30076005 DOI: 10.1016/j.chroma.2018.07.055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 07/13/2018] [Accepted: 07/17/2018] [Indexed: 10/28/2022]
Abstract
In this study, we propose a novel approach for the determination of total dissolved nitrogen (TDN) in seawater combining high-precision isotope dilution GC-MS with persulfate digestion. A 2 mL sample aliquot was digested with an alkaline solution of persulfate to convert nitrogen containing compounds to nitrate. Digested samples were spiked with 15NO3- internal standard and treated with aqueous triethyloxonium to convert the analyte into volatile EtONO2. This derivative was readily separated from the matrix under gaseous form and could be sampled from the headspace before GC-MS analysis. The resulting chromatograms showed a stable flat baseline with EtONO2 as the only eluting peak (retention time 2.75 min on a DB 5.625 column). Such an approach provides specificity and obviates the shortcomings of current detection methods employed to analyze seawater samples after digestion with persulfate. In negative chemical ionization mode, the method reached a detection limit of 0.5 μmol/kg TDN (7 ng/g N) and could be applied to quantify seawater samples with 1-25 μmol/kg TDN. On the upper end of the range, quantitation could be repeated within 1%, whereas on a 6 μmol/kg TDN sample repeatability was 2.3% on eight measurements. The method was employed in two proficiency testing exercises providing results in agreement with consensus values. We investigated the impact of reagent blank and we implemented a blank-matching optimal design to account for such contribution. Finally, we performed a study on the yield of persulfate oxidation for organic and inorganic nitrogen compounds typically present in seawater. Whilst nitrite and ammonium are fully converted to nitrate, more complex organic molecules showed recoveries varying from 70% to 100%.
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Affiliation(s)
- Enea Pagliano
- National Research Council of Canada, 1200 Montreal Road, K1A 0R6 Ottawa, Ontario, Canada.
| | - Beatrice Campanella
- Consiglio Nazionale delle Ricerche (CNR), Istituto di Chimica dei Composti Organometallici, UOS di Pisa, Via Moruzzi 1, 56124 Pisa, Italy
| | - Lisa Shi
- National Research Council of Canada, 1200 Montreal Road, K1A 0R6 Ottawa, Ontario, Canada
| | - Marie-Pier Thibeault
- National Research Council of Canada, 1200 Montreal Road, K1A 0R6 Ottawa, Ontario, Canada
| | - Massimo Onor
- Consiglio Nazionale delle Ricerche (CNR), Istituto di Chimica dei Composti Organometallici, UOS di Pisa, Via Moruzzi 1, 56124 Pisa, Italy
| | - Steven Crum
- QUASIMEME, NL-6700 EC Wageningen, Bornsesteeg 10, 6721 NG Bennekom, The Netherlands
| | - Jeremy E Melanson
- National Research Council of Canada, 1200 Montreal Road, K1A 0R6 Ottawa, Ontario, Canada
| | - Zoltán Mester
- National Research Council of Canada, 1200 Montreal Road, K1A 0R6 Ottawa, Ontario, Canada
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11
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Chance RJ, Hamilton JF, Carpenter LJ, Hackenberg SC, Andrews SJ, Wilson TW. Water-Soluble Organic Composition of the Arctic Sea Surface Microlayer and Association with Ice Nucleation Ability. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:1817-1826. [PMID: 29370515 DOI: 10.1021/acs.est.7b04072] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Organic matter in the sea surface microlayer (SML) may be transferred to the atmosphere as sea spray and hence influence the composition and properties of marine aerosol. Recent work has demonstrated that the SML contains material capable of heterogeneously nucleating ice, but the nature of this material remains largely unknown. Water-soluble organic matter was extracted from SML and underlying seawater from the Arctic and analyzed using a combination of mass spectrometric approaches. High performance liquid chromatography-ion trap mass spectrometry (LC-IT-MS), and Fourier transform ion cyclotron resonance MS (FT-ICR-MS), showed seawater extracts to be compositionally similar across all stations, whereas microlayer extracts had a different and more variable composition. LC-IT-MS demonstrated the enrichment of particular ions in the microlayer. Ice nucleation ability (defined as the median droplet freezing temperature) appeared to be related to the relative abundances of some ions, although the extracts themselves did not retain this property. Molecular formulas were assigned using LC-quadrupole time-of-flight MS (LC-TOF-MS2) and FT-ICR-MS. The ice nucleation tracer ions were associated with elevated biogenic trace gases, and were also observed in atmospheric aerosol collected during the summer, but not early spring suggesting a biogenic source of ice nuclei in the Arctic microlayer.
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Affiliation(s)
- Rosie J Chance
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York , Heslington, York, YO10 5DD, U.K
| | - Jacqueline F Hamilton
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York , Heslington, York, YO10 5DD, U.K
| | - Lucy J Carpenter
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York , Heslington, York, YO10 5DD, U.K
| | - Sina C Hackenberg
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York , Heslington, York, YO10 5DD, U.K
| | - Stephen J Andrews
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York , Heslington, York, YO10 5DD, U.K
| | - Theodore W Wilson
- School of Earth and Environment, University of Leeds , Woodhouse Lane, Leeds, LS2 9TJ, U.K
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12
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Cochran RE, Laskina O, Trueblood JV, Estillore AD, Morris HS, Jayarathne T, Sultana CM, Lee C, Lin P, Laskin J, Laskin A, Dowling JA, Qin Z, Cappa CD, Bertram TH, Tivanski AV, Stone EA, Prather KA, Grassian VH. Molecular Diversity of Sea Spray Aerosol Particles: Impact of Ocean Biology on Particle Composition and Hygroscopicity. Chem 2017. [DOI: 10.1016/j.chempr.2017.03.007] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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13
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Jayarathne T, Sultana CM, Lee C, Malfatti F, Cox JL, Pendergraft MA, Moore KA, Azam F, Tivanski AV, Cappa CD, Bertram TH, Grassian VH, Prather KA, Stone EA. Enrichment of Saccharides and Divalent Cations in Sea Spray Aerosol During Two Phytoplankton Blooms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:11511-11520. [PMID: 27709902 DOI: 10.1021/acs.est.6b02988] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Sea spray aerosol (SSA) is a globally important source of particulate matter. A mesocosm study was performed to determine the relative enrichment of saccharides and inorganic ions in nascent fine (PM2.5) and coarse (PM10-2.5) SSA and the sea surface microlayer (SSML) relative to bulk seawater. Saccharides comprise a significant fraction of organic matter in fine and coarse SSA (11 and 27%, respectively). Relative to sodium, individual saccharides were enriched 14-1314-fold in fine SSA, 3-138-fold in coarse SSA, but only up to 1.0-16.2-fold in SSML. Enrichments in SSML were attributed to rising bubbles that scavenge surface-active species from seawater, while further enrichment in fine SSA likely derives from bubble films. Mean enrichment factors for major ions demonstrated significant enrichment in fine SSA for potassium (1.3), magnesium (1.4), and calcium (1.7), likely because of their interactions with organic matter. Consequently, fine SSA develops a salt profile significantly different from that of seawater. Maximal enrichments of saccharides and ions coincided with the second of two phytoplankton blooms, signifying the influence of ocean biology on selective mass transfer across the ocean-air interface.
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Affiliation(s)
- Thilina Jayarathne
- Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States
| | - Camille M Sultana
- Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States
| | - Christopher Lee
- Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States
| | - Francesca Malfatti
- Scripps Institution of Oceanography, University of California, San Diego , La Jolla, California 92037, United States
- OGS, National Institute of Oceanography and Experimental Geophysics , Trieste 34100, Italy
| | - Joshua L Cox
- Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States
| | - Matthew A Pendergraft
- Scripps Institution of Oceanography, University of California, San Diego , La Jolla, California 92037, United States
| | - Kathryn A Moore
- Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States
| | - Farooq Azam
- Scripps Institution of Oceanography, University of California, San Diego , La Jolla, California 92037, United States
| | - Alexei V Tivanski
- Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States
| | - Christopher D Cappa
- Department of Civil and Environmental Engineering, University of California, Davis , Davis, California 95616, United States
| | - Timothy H Bertram
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Vicki H Grassian
- Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States
| | - Kimberly A Prather
- Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States
| | - Elizabeth A Stone
- Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States
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14
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Wilson TW, Ladino LA, Alpert PA, Breckels MN, Brooks IM, Browse J, Burrows SM, Carslaw KS, Huffman JA, Judd C, Kilthau WP, Mason RH, McFiggans G, Miller LA, Nájera JJ, Polishchuk E, Rae S, Schiller CL, Si M, Temprado JV, Whale TF, Wong JPS, Wurl O, Yakobi-Hancock JD, Abbatt JPD, Aller JY, Bertram AK, Knopf DA, Murray BJ. A marine biogenic source of atmospheric ice-nucleating particles. Nature 2015; 525:234-8. [DOI: 10.1038/nature14986] [Citation(s) in RCA: 345] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 07/17/2015] [Indexed: 11/09/2022]
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15
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Shaloski MA, Sobyra TB, Nathanson GM. DCl Transport through Dodecyl Sulfate Films on Salty Glycerol: Effects of Seawater Ions on Gas Entry. J Phys Chem A 2015; 119:12357-66. [DOI: 10.1021/acs.jpca.5b07298] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Michael A. Shaloski
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Thomas B. Sobyra
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Gilbert M. Nathanson
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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16
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Huang YJ, Brimblecombe P, Lee CL, Latif MT. Surfactants in the sea-surface microlayer and sub-surface water at estuarine locations: Their concentration, distribution, enrichment, and relation to physicochemical characteristics. MARINE POLLUTION BULLETIN 2015; 97:78-84. [PMID: 26093815 DOI: 10.1016/j.marpolbul.2015.06.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/11/2015] [Accepted: 06/12/2015] [Indexed: 06/04/2023]
Abstract
Samples of sea-surface microlayer (SML) and sub-surface water (SSW) were collected from two areas-Kaohsiung City (Taiwan) and the southwest coast of Peninsular Malaysia to study the influence of SML on enrichment and distribution and to compare SML with the SSW. Anionic surfactants (MBAS) predominated in this study and were significantly higher in Kaohsiung than in Malaysia. Industrial areas in Kaohsiung were enriched with high loads of anthropogenic sources, accounted for higher surfactant amounts, and pose higher environmental disadvantages than in Malaysia, where pollutants were associated with agricultural activities. The dissolved organic carbon (DOC), MBAS, and cationic surfactant (DBAS) concentrations in the SML correlated to the SSW, reflecting exchanges between the SML and SSW in Kaohsiung. The relationships between surfactants and the physiochemical parameters indicated that DOC and saltwater dilution might affect the distributions of MBAS and DBAS in Kaohsiung. In Malaysia, DOC might be the important factor controlling DBAS.
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Affiliation(s)
- Yun-Jie Huang
- Department of Marine Environment and Engineering, National Sun Yat-sen University, 80424 Kaohsiung, Taiwan, ROC
| | - Peter Brimblecombe
- School of Energy and Environment, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Chon-Lin Lee
- Department of Marine Environment and Engineering, National Sun Yat-sen University, 80424 Kaohsiung, Taiwan, ROC; Department of Public Health, College of Health Sciences, Kaohsiung Medical University, 80708 Kaohsiung, Taiwan, ROC; Kuroshio Research Group, Asia-Pacific Ocean Research Center, National Sun Yat-sen University, 80424 Kaohsiung, Taiwan, ROC; Research Center of Environmental Medicine, Kaohsiung Medical University, 80708 Kaohsiung, Taiwan, ROC.
| | - Mohd Talib Latif
- School of Environment and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia; Institute for Environment and Development (LESTARI), Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
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17
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Ryder OS, Campbell NR, Shaloski M, Al-Mashat H, Nathanson GM, Bertram TH. Role of Organics in Regulating ClNO2 Production at the Air–Sea Interface. J Phys Chem A 2015; 119:8519-26. [DOI: 10.1021/jp5129673] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- O. S. Ryder
- Department
of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - N. R. Campbell
- Department
of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - M. Shaloski
- Department
of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - H. Al-Mashat
- Department
of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - G. M. Nathanson
- Department
of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - T. H. Bertram
- Department
of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
- Department
of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
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18
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Quinn PK, Collins DB, Grassian VH, Prather KA, Bates TS. Chemistry and Related Properties of Freshly Emitted Sea Spray Aerosol. Chem Rev 2015; 115:4383-99. [DOI: 10.1021/cr500713g] [Citation(s) in RCA: 232] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Patricia K. Quinn
- Pacific
Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, Washington 98115, United States
| | - Douglas B. Collins
- Center
for Aerosol Impacts on Climate and the Environment, University of California at San Diego, La Jolla, California 92024, United States
| | - Vicki H. Grassian
- Center
for Aerosol Impacts on Climate and the Environment, University of California at San Diego, La Jolla, California 92024, United States
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Kimberly A. Prather
- Center
for Aerosol Impacts on Climate and the Environment, University of California at San Diego, La Jolla, California 92024, United States
| | - Timothy S. Bates
- Joint
Institute for the Study of the Atmosphere and Ocean, University of Washington, Seattle, Washington 98105, United States
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19
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Guasco TL, Cuadra-Rodriguez LA, Pedler BE, Ault AP, Collins DB, Zhao D, Kim MJ, Ruppel MJ, Wilson SC, Pomeroy RS, Grassian VH, Azam F, Bertram TH, Prather KA. Transition metal associations with primary biological particles in sea spray aerosol generated in a wave channel. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:1324-1333. [PMID: 24328130 DOI: 10.1021/es403203d] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In the ocean, breaking waves generate air bubbles which burst at the surface and eject sea spray aerosol (SSA), consisting of sea salt, biogenic organic species, and primary biological aerosol particles (PBAP). Our overall understanding of atmospheric biological particles of marine origin remains poor. Here, we perform a control experiment, using an aerosol time-of-flight mass spectrometer to measure the mass spectral signatures of individual particles generated by bubbling a salt solution before and after addition of heterotrophic marine bacteria. Upon addition of bacteria, an immediate increase occurs in the fraction of individual particle mass spectra containing magnesium, organic nitrogen, and phosphate marker ions. These biological signatures are consistent with 21% of the supermicrometer SSA particles generated in a previous study using breaking waves in an ocean-atmosphere wave channel. Interestingly, the wave flume mass spectral signatures also contain metal ions including silver, iron, and chromium. The nascent SSA bioparticles produced in the wave channel are hypothesized to be as follows: (1) whole or fragmented bacterial cells which bioaccumulated metals and/or (2) bacteria-derived colloids or biofilms which adhered to the metals. This study highlights the potential for transition metals, in combination with specific biomarkers, to serve as unique indicators for the presence of marine PBAP, especially in metal-impacted coastal regions.
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Affiliation(s)
- Timothy L Guasco
- Department of Chemistry and Biochemistry, University of California , San Diego, La Jolla, California, 92093
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20
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Santos AL, Baptista I, Gomes NCM, Henriques I, Almeida A, Correia A, Cunha A. Contribution of chemical water properties to the differential responses of bacterioneuston and bacterioplankton to ultraviolet-B radiation. FEMS Microbiol Ecol 2013; 87:517-35. [PMID: 24164491 DOI: 10.1111/1574-6941.12239] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 09/24/2013] [Accepted: 10/21/2013] [Indexed: 11/26/2022] Open
Abstract
The surface microlayer (SML) is characterized by different physicochemical properties from underlying waters (UW). However, whether these differences in abiotic factors underlie the distinct sensitivity of bacterioneuston (i.e. SML bacteria) and bacterioplankton to environmental stressors remains to be addressed. We investigated the contribution of abiotic factors to the UV-B sensitivity of bacterioneuston and bacterioplankton. Nutrients (especially nitrogen and phosphate) emerged as important determinants of bacterial UV-B sensitivity. The role of particles, nutrients, and dissolved organic components on bacterial UV-B sensitivity was further evaluated using dilution cultures. Filtered samples were twofold more UV sensitive than unfiltered samples, suggesting a UV-protective effect of particles. High nutrient concentrations attenuated bacterial UV-B sensitivity (up to 40%), compared with unamended conditions, by influencing bacterial physiology and/or community composition. Suspending cells in natural water, particularly from the SML, also attenuated UV-B sensitivity (up to 23%), compared with suspension in an artificial mineral solution. Bioassays using Pseudomonas sp. strain NT5I1.2B revealed that chemical water properties influence UV-induced oxidative damage. UV-B sensitivity was associated with high cell-specific activities. The chemical environment of the SML and UW influences UV-B effects on the corresponding bacterial communities. Maintaining low cell activities might be advantageous in stressful environments, like the SML.
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Affiliation(s)
- Ana L Santos
- Department of Biology and CESAM, University of Aveiro, Aveiro, Portugal
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21
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Dilbeck CW, Finlayson-Pitts BJ. Hydroxyl radical oxidation of phospholipid-coated NaCl particles. Phys Chem Chem Phys 2013; 15:9833-44. [PMID: 23676928 DOI: 10.1039/c3cp51237a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Biological organic compounds mixed with NaCl and other inorganic compounds in sea-salt aerosol particles react in air with oxidants such as ozone and hydroxyl (OH) radicals. Laboratory studies of model systems can provide insight into these reactions. We report here studies of the kinetics and mechanism of oxidation of unsaturated 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) on NaCl by gas phase OH in air at room temperature and 1 atm pressure using diffuse reflection infrared Fourier transform spectrometry (DRIFTS) and matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) to identify possible structures of surface-bound reaction products. For comparison, some studies were also carried out on the saturated 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) on NaCl. The calculated concentration of hydroxyl radicals, generated by photolysis of isopropyl nitrite, was (1.6-6.4) × 10(8) radicals cm(-3). Surface-bound aldehydes, ketones, organic nitrates and nitrate ions were identified as products of these reactions and structures of potential products were proposed based on mechanistic considerations combined with the MALDI-TOF-MS and DRIFTS spectra. The loss rate of vinyl hydrogen, =C-H, at 3008 cm(-1) was used to obtain a lower limit for the rate constant (k1) for addition of OH to the double bond, k1 > (3 ± 1) × 10(-13) cm(3) molecule(-1) s(-1) (1s), corresponding to a reaction probability of γ(add) > (4 ± 1) × 10(-3) (1s). Assuming that abstraction from -CH2- groups in POPC is the same as for DPPC, the percentage of the reaction that occurs by addition is ~80%. This is similar to the percent addition predicted using structure-reactivity relationships for gas-phase reactions. Decreasing the amount of POPC relative to NaCl resulted in more nitrate ion formation and less relative loss of POPC, and increasing the OH concentration resulted in a more rapid loss of POPC and faster product formation. These studies suggest that under atmospheric conditions with an OH concentration of 5 × 10(6) radicals cm(-3), the lifetime of POPC with respect to OH is <6 days.
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Affiliation(s)
- Christopher W Dilbeck
- Department of Chemistry, University of California Irvine, Irvine, CA 92697-2025, USA
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