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Yu J, Gong Y, Nair P, Liggio J, Peng H, Abbatt JPD. Multiphase Ozonolysis of Bisphenol A: Chemical Transformations on Surfaces in the Environment. Environ Sci Technol 2024; 58:3931-3941. [PMID: 38349611 DOI: 10.1021/acs.est.3c08932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
High global plastic production volumes have led to the widespread presence of bisphenol compounds in human living and working environments. The most common bisphenol, bisphenol A (BPA), despite being endocrine disruptive and estrogenic, is still not fully banned worldwide, leading to continued human exposure via particles in air, dust, and surfaces in both outdoor and indoor environments. While its abundance is well documented, few studies have addressed the chemical transformations of BPA, the properties of its reactive products, and their toxicity. Here, the first gas-surface multiphase ozonolysis experiment of BPA thin films, at a constant ozone mixing ratio of 100 ppb, was performed in a flow tube for periods up to 24 h. Three transformation products involving the addition of 1, 2, and 3 oxygen atoms to the molecule were identified by LC-ESI-HRMS analyses. Exposure of indoor air to thin BPA surface films and BPA-containing thermal paper over periods of days validated the flow tube experiments, demonstrating the rapid nature of this multiphase ozonolysis reaction at atmospherically relevant ozone levels. Multiple transformation pathways are proposed that are likely applicable to not only BPA but also emerging commercial bisphenol products.
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Affiliation(s)
- Jie Yu
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Yufeng Gong
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Pranav Nair
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - John Liggio
- Air Quality Processes Research Section, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Hui Peng
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
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2
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He M, Ditto JC, Gardner L, Machesky J, Hass-Mitchell TN, Chen C, Khare P, Sahin B, Fortner JD, Plata DL, Drollette BD, Hayden KL, Wentzell JJB, Mittermeier RL, Leithead A, Lee P, Darlington A, Wren SN, Zhang J, Wolde M, Moussa SG, Li SM, Liggio J, Gentner DR. Total organic carbon measurements reveal major gaps in petrochemical emissions reporting. Science 2024; 383:426-432. [PMID: 38271520 DOI: 10.1126/science.adj6233] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 12/15/2023] [Indexed: 01/27/2024]
Abstract
Anthropogenic organic carbon emissions reporting has been largely limited to subsets of chemically speciated volatile organic compounds. However, new aircraft-based measurements revealed total gas-phase organic carbon emissions that exceed oil sands industry-reported values by 1900% to over 6300%, the bulk of which was due to unaccounted-for intermediate-volatility and semivolatile organic compounds. Measured facility-wide emissions represented approximately 1% of extracted petroleum, resulting in total organic carbon emissions equivalent to that from all other sources across Canada combined. These real-world observations demonstrate total organic carbon measurements as a means of detecting unknown or underreported carbon emissions regardless of chemical features. Because reporting gaps may include hazardous, reactive, or secondary air pollutants, fully constraining the impact of anthropogenic emissions necessitates routine, comprehensive total organic carbon monitoring as an inherent check on mass closure.
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Affiliation(s)
- Megan He
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Jenna C Ditto
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Lexie Gardner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Jo Machesky
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Tori N Hass-Mitchell
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Christina Chen
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Peeyush Khare
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Bugra Sahin
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - John D Fortner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Desiree L Plata
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Brian D Drollette
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Katherine L Hayden
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | - Jeremy J B Wentzell
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | - Richard L Mittermeier
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | - Amy Leithead
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | - Patrick Lee
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | - Andrea Darlington
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | - Sumi N Wren
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | - Junhua Zhang
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | | | - Samar G Moussa
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | - Shao-Meng Li
- College of Environmental Sciences and Engineering, Peking University, Beijing, China
| | - John Liggio
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada
| | - Drew R Gentner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
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3
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Liggio J, Li SM. Reply to: Uncertainty and bias in Liggio et al. (2019) on CO 2 emissions from oil sands operations. Nat Commun 2023; 14:5407. [PMID: 37673894 PMCID: PMC10482959 DOI: 10.1038/s41467-023-40819-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 08/09/2023] [Indexed: 09/08/2023] Open
Affiliation(s)
- John Liggio
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin St, Toronto, Ontario, M3H 5T4, Canada.
| | - Shao-Meng Li
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin St, Toronto, Ontario, M3H 5T4, Canada
- College of Environmental Sciences and Engineering, Peking University, 100871, Beijing, China
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4
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Wang C, Liggio J, Wentzell JJB, Jorga S, Folkerson A, Abbatt JPD. Chloramines as an important photochemical source of chlorine atoms in the urban atmosphere. Proc Natl Acad Sci U S A 2023; 120:e2220889120. [PMID: 37459517 PMCID: PMC10372683 DOI: 10.1073/pnas.2220889120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 06/10/2023] [Indexed: 07/29/2023] Open
Abstract
Monochloramine, dichloramine and trichloramine (NH2Cl, NHCl2, NCl3) are measured in the ambient atmosphere, in downtown Toronto in summer (median 39, 15 and 2.8 ppt) and winter (median 11, 7.3 and 0.7 ppt). NCl3 and NHCl2 were also measured in summer (median 1.3 and 14 ppt) from a suburban Toronto location. Measurements at two locations demonstrate prevalence of chloramines in an urban atmosphere. At both sites, NCl3 exhibits a strong diel pattern with maximum values during the night, and photolytic loss with sunrise. At the downtown site, a strong positive correlation between NH2Cl and NHCl2 in the summer night indicates a common source, with daily average peak mixing ratios approaching 500 and 250 ppt, respectively. As a previously unidentified source of chlorine (Cl) atoms, we demonstrate that NCl3 photolysis contributes 49 to 82% of the total local summertime Cl production rate at different times during the day with an average noontime peak of 3.8 × 105 atoms/cm3/s, with smaller contributions from ClNO2 and Cl2. Photolysis of NH2Cl and NHCl2 may augment this Cl production rate. Our measurements also demonstrate a daytime enhancement of chloroacetone in both the summer and winter, demonstrating the importance of Cl photochemistry. The results suggest that chloramines are an important source of Cl atoms in urban areas, with potential impacts on the abundance of organic compounds, ozone, nitrogen oxides, and particulate matter. Future studies should explore the vertical gradients of chloramines and their contribution to Cl production throughout the boundary layer.
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Affiliation(s)
- Chen Wang
- Guangdong Provincial Observation and Research Station for Coastal Atmosphere and Climate of the Greater Bay Area, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen518055, China
- Department of Chemistry, University of Toronto, Toronto, ONM5S 3H6, Canada
- Shenzhen Key Laboratory of Precision Measurement and Early Warning Technology for Urban Environmental Health Risks, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen518055, China
| | - John Liggio
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ONM3H 5T4, Canada
| | - Jeremy J. B. Wentzell
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ONM3H 5T4, Canada
| | - Spiro Jorga
- Department of Chemistry, University of Toronto, Toronto, ONM5S 3H6, Canada
| | - Andrew Folkerson
- Department of Chemistry, University of Toronto, Toronto, ONM5S 3H6, Canada
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Liu Y, Huang Y, Liggio J, Hayden K, Mihele C, Wentzell J, Wheeler M, Leithead A, Moussa S, Xie C, Yang Y, Zhang Y, Han T, Li SM. A newly developed Lagrangian chemical transport scheme: Part 1. Simulation of a boreal forest fire plume. Sci Total Environ 2023; 880:163232. [PMID: 37023817 DOI: 10.1016/j.scitotenv.2023.163232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/29/2023] [Accepted: 03/29/2023] [Indexed: 05/27/2023]
Abstract
Forest fire research over the last several decades has improved the understanding of fire emissions and impacts. Nevertheless, the evolution of forest fire plumes remains poorly quantified and understood. Here, a Lagrangian chemical transport model, the Forward Atmospheric Stochastic Transport model coupled with the Master Chemical Mechanism (FAST-MCM), has been developed to simulate the transport and chemical transformations of plumes from a boreal forest fire over several hours since their emission. The model results for NOx (NO and NO2), O3, HONO, HNO3, pNO3 and 70 VOC species are compared with airborne in-situ measurements within plume centers and their surrounding portions during the transport. Comparisons between simulation results and measurements show that the FAST-MCM model can properly reproduce the physical and chemical evolution of forest fire plumes. The results indicate that the model can be an important tool used to aid the understanding of the downwind impacts of forest fire plumes.
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Affiliation(s)
- Yayong Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China 100871
| | - Yufei Huang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China 100871
| | - John Liggio
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Katherine Hayden
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Cris Mihele
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Jeremy Wentzell
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Michael Wheeler
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Amy Leithead
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Samar Moussa
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Conghui Xie
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China 100871
| | - Yanrong Yang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China 100871
| | - Yuheng Zhang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China 100871
| | - Tianran Han
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China 100871
| | - Shao-Meng Li
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China 100871.
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6
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Wren SN, McLinden CA, Griffin D, Li SM, Cober SG, Darlington A, Hayden K, Mihele C, Mittermeier RL, Wheeler MJ, Wolde M, Liggio J. Aircraft and satellite observations reveal historical gap between top-down and bottom-up CO 2 emissions from Canadian oil sands. PNAS Nexus 2023; 2:pgad140. [PMID: 37168672 PMCID: PMC10165801 DOI: 10.1093/pnasnexus/pgad140] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 05/13/2023]
Abstract
Measurement-based estimates of greenhouse gas (GHG) emissions from complex industrial operations are challenging to obtain, but serve as an important, independent check on inventory-reported emissions. Such top-down estimates, while important for oil and gas (O&G) emissions globally, are particularly relevant for Canadian oil sands (OS) operations, which represent the largest O&G contributor to national GHG emissions. We present a multifaceted top-down approach for estimating CO2 emissions that combines aircraft-measured CO2/NOx emission ratios (ERs) with inventory and satellite-derived NOx emissions from Ozone Monitoring Instrument (OMI) and TROPOspheric Ozone Monitoring Instrument (TROPOMI) and apply it to the Athabasca Oil Sands Region (AOSR) in Alberta, Canada. Historical CO2 emissions were reconstructed for the surface mining region, and average top-down estimates were found to be >65% higher than facility-reported, bottom-up estimates from 2005 to 2020. Higher top-down vs. bottom-up emissions estimates were also consistently obtained for individual surface mining and in situ extraction facilities, which represent a growing category of energy-intensive OS operations. Although the magnitudes of the measured discrepancies vary between facilities, they combine such that the observed reporting gap for total AOSR emissions is ≥(31 ± 8) Mt for each of the last 3 years (2018-2020). This potential underestimation is large and broadly highlights the importance of continued review and refinement of bottom-up estimation methodologies and inventories. The ER method herein offers a powerful approach for upscaling measured facility-level or regional fossil fuel CO2 emissions by taking advantage of satellite remote sensing observations.
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Affiliation(s)
- Sumi N Wren
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
| | - Chris A McLinden
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
| | - Debora Griffin
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
| | - Shao-Meng Li
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Stewart G Cober
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
| | - Andrea Darlington
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
| | - Katherine Hayden
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
| | - Cristian Mihele
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
| | - Richard L Mittermeier
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
| | - Michael J Wheeler
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
| | - Mengistu Wolde
- Flight Research Laboratory, National Research Council Canada Aerospace Research Centre, Ottawa, ON K1V 1J8, Canada
| | - John Liggio
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
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7
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Horb EC, Wentworth GR, Makar PA, Liggio J, Hayden K, Boutzis EI, Beausoleil DL, Hazewinkel RO, Mahaffey AC, Sayanda D, Wyatt F, Dubé MG. A decadal synthesis of atmospheric emissions, ambient air quality, and deposition in the oil sands region. Integr Environ Assess Manag 2022; 18:333-360. [PMID: 34676977 PMCID: PMC9299045 DOI: 10.1002/ieam.4539] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 09/24/2021] [Accepted: 10/01/2021] [Indexed: 05/20/2023]
Abstract
This review is part of a series synthesizing peer-reviewed literature from the past decade on environmental monitoring in the oil sands region (OSR) of northeastern Alberta. It focuses on atmospheric emissions, air quality, and deposition in and downwind of the OSR. Most published monitoring and research activities were concentrated in the surface-mineable region in the Athabasca OSR. Substantial progress has been made in understanding oil sands (OS)-related emission sources using multiple approaches: airborne measurements, satellite measurements, source emission testing, deterministic modeling, and source apportionment modeling. These approaches generally yield consistent results, indicating OS-related sources are regional contributors to nearly all air pollutants. Most pollutants exhibit enhanced air concentrations within ~20 km of surface-mining activities, with some enhanced >100 km downwind. Some pollutants (e.g., sulfur dioxide, nitrogen oxides) undergo transformations as they are transported through the atmosphere. Deposition rates of OS-related substances primarily emitted as fugitive dust are enhanced within ~30 km of surface-mining activities, whereas gaseous and fine particulate emissions have a more diffuse deposition enhancement pattern extending hundreds of kilometers downwind. In general, air quality guidelines are not exceeded, although these single-pollutant thresholds are not comprehensive indicators of air quality. Odor events have occurred in communities near OS industrial activities, although it can be difficult to attribute events to specific pollutants or sources. Nitrogen, sulfur, polycyclic aromatic compounds (PACs), and base cations from OS sources occur in the environment, but explicit and deleterious responses of organisms to these pollutants are not as apparent across all study environments; details of biological monitoring are discussed further in other papers in this special series. However, modeling of critical load exceedances suggests that, at continued emission levels, ecological change may occur in future. Knowledge gaps and recommendations for future work to address these gaps are also presented. Integr Environ Assess Manag 2022;18:333-360. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
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Affiliation(s)
- Erin C. Horb
- Resource Stewardship DivisionAlberta Environment and ParksCalgaryAlbertaCanada
| | - Gregory R. Wentworth
- Resource Stewardship DivisionAlberta Environment and ParksEdmontonAlbertaCanada
- Present address: Environmental Protection BranchEnvironment and Climate Change CanadaEdmontonAlbertaCanada
| | - Paul A. Makar
- Air Quality Research DivisionEnvironment and Climate Change CanadaTorontoOntarioCanada
| | - John Liggio
- Air Quality Research DivisionEnvironment and Climate Change CanadaTorontoOntarioCanada
| | - Katherine Hayden
- Air Quality Research DivisionEnvironment and Climate Change CanadaTorontoOntarioCanada
| | | | | | | | - Ashley C. Mahaffey
- Resource Stewardship DivisionAlberta Environment and ParksCalgaryAlbertaCanada
| | - Diogo Sayanda
- Resource Stewardship DivisionAlberta Environment and ParksCalgaryAlbertaCanada
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8
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Moussa SG, Staebler RM, You Y, Leithead A, Yousif MA, Brickell P, Beck J, Jiang Z, Liggio J, Li SM, Wren SN, Brook JR, Darlington A, Cober SG. Fugitive Emissions of Volatile Organic Compounds from a Tailings Pond in the Oil Sands Region of Alberta. Environ Sci Technol 2021; 55:12831-12840. [PMID: 34524801 DOI: 10.1021/acs.est.1c02325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Tailings ponds in the oil sands (OS) region in Alberta, Canada, have been associated with fugitive emissions of volatile organic compounds (VOCs) and other pollutants to the atmosphere. However, the contribution of tailings ponds to the total fugitive emissions of VOCs from OS operations remains uncertain. To address this knowledge gap, a field study was conducted in the summer of 2017 at Suncor's Pond 2/3 to estimate emissions of a suite of pollutants including 68 VOCs using a combination of micrometeorological methods and measurements from a flux tower. The results indicate that in 2017, Pond 2/3 was an emission source of 3322 ± 727 tons of VOCs including alkanes, aromatics, and oxygenated and sulfur-containing organics. While the total VOC emissions were approximately a factor of 2 higher than those reported by Suncor, the individual VOC species emissions varied by up to a factor of 12. A chemical mass balance (CMB) receptor model was used to estimate the contribution of the tailings pond to VOC pollution events in a nearby First Nations and Metis community in Fort McKay. CMB results indicate that Suncor Pond 2/3 contributed up to 57% to the total mass of VOCs measured at Fort McKay, reinforcing the importance of accurate VOC emission estimation methods for tailings ponds.
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Affiliation(s)
- Samar G Moussa
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Ralf M Staebler
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Yuan You
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Amy Leithead
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Meguel A Yousif
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Peter Brickell
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - James Beck
- Suncor Energy Inc., Calgary, Alberta T2P 3Y7, Canada
| | - Zhimei Jiang
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - John Liggio
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Shao-Meng Li
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
- College of Environmental Science and Engineering, Peking University, Beijing 100871, China
| | - Sumi N Wren
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Jeffrey R Brook
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
- Dalla Lana School of Public Health and Department of Chemical Engineering and Applied Chemistry, University of Toronto, 223 College Street, Toronto, Ontario M5T 1R4, Canada
| | - Andrea Darlington
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Stewart G Cober
- Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
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9
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Li K, Wentzell JJB, Liu Q, Leithead A, Moussa SG, Wheeler MJ, Han C, Lee P, Li SM, Liggio J. Evolution of Atmospheric Total Organic Carbon from Petrochemical Mixtures. Environ Sci Technol 2021; 55:12841-12851. [PMID: 34525806 DOI: 10.1021/acs.est.1c02620] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Reactive organic compounds play a central role in the formation of ozone and secondary organic aerosols. The ability to accurately predict their fate, in part, relies upon quantitative knowledge of the chemical and physical parameters associated with the total organic carbon (TOC), which includes both precursors and oxidation products that evolve in the atmosphere over short to long time scales. However, such knowledge, obtained via limited carbon closure experiments, has not been attained for complex anthropogenic emissions. Here we present the first comprehensive characterization of TOC in the atmospheric oxidation of organic vapors from light and heavy oil mixtures associated with oil sand operations. Despite the complexity of the investigated oil mixtures, we are able to achieve carbon closure (83-116%) within the uncertainties (±20%), with the degree of the closure being dependent upon the vapor composition and NOx levels. In contrast to biogenic precursors (e.g., α-pinene), the photochemical time scale required for a largely complete oxidation and evolution of chemical parameters is very long for the petrochemical vapors (i.e., ∼7-10 days vs ∼1 day), likely due to the lower initial precursor reactivity. This suggests that petrochemical emissions and their impacts are likely to extend further spatially than biogenic emissions, and retain more of their complex composition and reactivity for many days. The results of this work provide key parameters to regional models for further improving the representation of the chemical evolution of petrochemical emissions.
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Affiliation(s)
- Kun Li
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - Jeremy J B Wentzell
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Qifan Liu
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Amy Leithead
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Samar G Moussa
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Michael J Wheeler
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Chong Han
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Patrick Lee
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Shao-Meng Li
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - John Liggio
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
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10
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Cheng Y, Li SM, Liggio J, Gordon M, Darlington A, Zheng Q, Moran M, Liu P, Wolde M. Top-Down Determination of Black Carbon Emissions from Oil Sand Facilities in Alberta, Canada Using Aircraft Measurements. Environ Sci Technol 2020; 54:412-418. [PMID: 31834792 DOI: 10.1021/acs.est.9b05522] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Black carbon (BC) emissions from the Canadian oil sand (OS) surface mining facilities in Alberta were investigated using aircraft measurements. BC emission rates were derived with a top-down mass balance approach and were found to be linearly related to the volume of oil sand ore mined at each facility. Two emission factors were determined from the measurements; production-based BC emission factors were in the range of 0.6-1.7 g/tonne mined OS ore, whereas fuel-based BC emission factors were between 95 and 190 mg/kg-fuel, depending upon the facility. The annual BC emission, at 707 ± 117 tonnes/year for the facilities, was determined using the production-based emission factors and annual production data. Although this annual emission is in reasonable agreement with the BC annual emissions reported in the latest version of the Canadian national BC inventory (within 16%), the relative split between off-road diesel and stack sources is significantly different between the measurements and the inventory. This measurement evidence highlights the fact that the stack sources of BC may be overestimated and the off-road diesel sources may be underestimated in the inventory and points to the need for improved BC emission data from diesel sources within facilities.
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Affiliation(s)
- Yuan Cheng
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Shao-Meng Li
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
- College of Environmental Science and Engineering, Peking University, Beijing 100871, China
| | - John Liggio
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Mark Gordon
- Department of Earth and Space Science and Engineering, York University, 4700 Keele Street, Toronto, Ontario M3J 1P3, Canada
| | - Andrea Darlington
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Qiong Zheng
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Michael Moran
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Peter Liu
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
| | - Mengistu Wolde
- National Research Council Canada, Flight Research Laboratory, Ottawa, Ontario K1A 0R6, Canada
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11
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Liu Q, Liggio J, Wu D, Saini A, Halappanavar S, Wentzell JJB, Harner T, Li K, Lee P, Li SM. Experimental Study of OH-Initiated Heterogeneous Oxidation of Organophosphate Flame Retardants: Kinetics, Mechanism, and Toxicity. Environ Sci Technol 2019; 53:14398-14408. [PMID: 31756294 DOI: 10.1021/acs.est.9b05327] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The environmental risks and health impacts associated with particulate organophosphate flame retardants (OPFRs), which are ubiquitous in the global atmosphere, have not been adequately assessed due to the lack of data on the reaction kinetics, products, and toxicity associated with their atmospheric transformations. Here, the importance of such transformations for OPFRs are explored by investigating the reaction kinetics, degradation chemical mechanisms, and toxicological evolution of two OPFRs (2-ethylhexyl diphenyl phosphate (EHDP) and diphenyl phosphate (DPhP)) coated on (NH4)2SO4 particles upon heterogeneous OH oxidation. The derived reaction rate constants for the heterogeneous loss of EHDP and DPhP are (1.12 ± 0.22) × 10-12 and (2.33 ± 0.14) × 10-12 cm3 molecules-1 s-1, respectively. Using recently developed real-time particle chemical composition measurements, particulate products from heterogeneous photooxidation and the associated degradation mechanisms for particulate OPFRs are reported for the first time. Subsequent cytotoxicity analysis of the unreacted and oxidized OPFR particles indicated that the overall particle cytotoxicity was reduced by up to 94% with heterogeneous photooxidation, likely due to a significantly lower cytotoxicity associated with the oxidized OPFR products relative to the parent OPFRs. The present work not only provides guidance for future field sampling for the detection of transformation products of OPFRs, but also strongly supports the ongoing risk assessment of these emerging chemicals and most critically, their products.
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Affiliation(s)
- Qifan Liu
- Air Quality Research Division , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - John Liggio
- Air Quality Research Division , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Dongmei Wu
- Environmental Health Science and Research Bureau , Health Canada , Ottawa , Ontario K1A 0K9 , Canada
| | - Amandeep Saini
- Air Quality Research Division , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Sabina Halappanavar
- Environmental Health Science and Research Bureau , Health Canada , Ottawa , Ontario K1A 0K9 , Canada
| | - Jeremy J B Wentzell
- Air Quality Research Division , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Tom Harner
- Air Quality Research Division , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Kun Li
- Air Quality Research Division , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Patrick Lee
- Air Quality Research Division , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Shao-Meng Li
- Air Quality Research Division , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
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12
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Li K, Liggio J, Han C, Liu Q, Moussa SG, Lee P, Li SM. Understanding the Impact of High-NO x Conditions on the Formation of Secondary Organic Aerosol in the Photooxidation of Oil Sand-Related Precursors. Environ Sci Technol 2019; 53:14420-14429. [PMID: 31751130 DOI: 10.1021/acs.est.9b05404] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Oil sands (OS) are an important type of heavy oil deposit, for which operations in Alberta, Canada, were recently found to be a large source of secondary organic aerosol (SOA). However, SOA formation from the OS mining, processing, and subsequent tailings, especially in the presence of NOx, remains unclear. Here, photooxidation experiments for OS-related precursors under high-NOx conditions were performed using an oxidation flow reactor, in which ∼95% of peroxy radicals (RO2) react with NO. The SOA yields under high-NOx conditions were found to be lower than yields under low-NOx conditions for all precursors, which is likely due to the higher volatilities of the products from the RO2 + NO pathway compared with RO2 + HO2. The SOA yields under high-NOx conditions show a strong dependence on pre-existing surface area (not observed in previous low-NOx experiments), again attributed to the higher product volatilities. Comparing the mass spectra of SOA formed from different precursors, we conclude that the fraction of m/z > 80 (F80) can be used as a parameter to separate different types of SOA in the region. In addition, particle-phase organic nitrate was found to be an important component (9-23%) of OS SOA formed under high-NOx conditions. These results have implications for better understanding the atmospheric processing of OS emissions.
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Affiliation(s)
- Kun Li
- Air Quality Process Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - John Liggio
- Air Quality Process Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Chong Han
- Air Quality Process Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Qifan Liu
- Air Quality Process Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Samar G Moussa
- Air Quality Process Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Patrick Lee
- Air Quality Process Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Shao-Meng Li
- Air Quality Process Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
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13
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Liu Q, Liggio J, Li K, Lee P, Li SM. Understanding the Impact of Relative Humidity and Coexisting Soluble Iron on the OH-Initiated Heterogeneous Oxidation of Organophosphate Flame Retardants. Environ Sci Technol 2019; 53:6794-6803. [PMID: 31117542 DOI: 10.1021/acs.est.9b01758] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The current uncertainties in the reactivity and atmospheric persistence of particle-associated chemicals present a challenge for the prediction of long-range transport and deposition of emerging chemicals such as organophosphate flame retardants, which are ubiquitous in the global environment. Here, the OH-initiated heterogeneous oxidation kinetics of organophosphate flame retardants (OPFRs) coated on inert (NH4)2SO4 and redox-active FeSO4 particles were systematically determined as a function of relative humidity (RH). The derived reaction rate constants for the heterogeneous loss of tricresyl phosphate (TCP; kTCP) and tris(2-butoxyethyl) phosphate (TBEP; kTBEP) were in the range of (2.69-3.57) × 10-12 and (3.06-5.55) × 10-12 cm3 molecules-1 s-1, respectively, depending on the RH and coexisting Fe(II) content. The kTCP (coated on (NH4)2SO4) was relatively constant over the investigated RH range while kTBEP was enhanced by up to 19% with increasing RH. For both OPFRs, the presence of Fe(II) enhanced their k by up to 53% over inert (NH4)2SO4. These enhancement effects (RH and Fe(II)) were attributed to fundamental changes in the organic phase state (higher RH lowered particle viscosity) and Fenton-type chemistry which resulted in the formation of reactive oxygen species, respectively. Such findings serve to emphasize the importance of ambient RH, the phase state of particle-bound organics in general, and the presence of coexisting metallic species for an accurate description of the degradation kinetics and aging of particulate OPFRs in models used to evaluate their atmospheric persistence.
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Affiliation(s)
- Qifan Liu
- Atmospheric Science and Technology Directorate, Science and Technology Branch , Environment Canada , 4905 Dufferin Street , Toronto , Ontario M3H 5T4 , Canada
| | - John Liggio
- Atmospheric Science and Technology Directorate, Science and Technology Branch , Environment Canada , 4905 Dufferin Street , Toronto , Ontario M3H 5T4 , Canada
| | - Kun Li
- Atmospheric Science and Technology Directorate, Science and Technology Branch , Environment Canada , 4905 Dufferin Street , Toronto , Ontario M3H 5T4 , Canada
| | - Patrick Lee
- Atmospheric Science and Technology Directorate, Science and Technology Branch , Environment Canada , 4905 Dufferin Street , Toronto , Ontario M3H 5T4 , Canada
| | - Shao-Meng Li
- Atmospheric Science and Technology Directorate, Science and Technology Branch , Environment Canada , 4905 Dufferin Street , Toronto , Ontario M3H 5T4 , Canada
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14
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Brook JR, Cober SG, Freemark M, Harner T, Li SM, Liggio J, Makar P, Pauli B. Advances in science and applications of air pollution monitoring: A case study on oil sands monitoring targeting ecosystem protection. J Air Waste Manag Assoc 2019; 69:661-709. [PMID: 31082314 DOI: 10.1080/10962247.2019.1607689] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The potential environmental impact of air pollutants emitted from the oil sands industry in Alberta, Canada, has received considerable attention. The mining and processing of bitumen to produce synthetic crude oil, and the waste products associated with this activity, lead to significant emissions of gaseous and particle air pollutants. Deposition of pollutants occurs locally (i.e., near the sources) and also potentially at distances downwind, depending upon each pollutant's chemical and physical properties and meteorological conditions. The Joint Oil Sands Monitoring Program (JOSM) was initiated in 2012 by the Government of Canada and the Province of Alberta to enhance or improve monitoring of pollutants and their potential impacts. In support of JOSM, Environment and Climate Change Canada (ECCC) undertook a significant research effort via three components: the Air, Water, and Wildlife components, which were implemented to better estimate baseline conditions related to levels of pollutants in the air and water, amounts of deposition, and exposures experienced by the biota. The criteria air contaminants (e.g., nitrogen oxides [NOx], sulfur dioxide [SO2], volatile organic compounds [VOCs], particulate matter with an aerodynamic diameter <2.5 μm [PM2.5]) and their secondary atmospheric products were of interest, as well as toxic compounds, particularly polycyclic aromatic compounds (PACs), trace metals, and mercury (Hg). This critical review discusses the challenges of assessing ecosystem impacts and summarizes the major results of these efforts through approximately 2018. Focus is on the emissions to the air and the findings from the Air Component of the ECCC research and linkages to observations of contaminant levels in the surface waters in the region, in aquatic species, as well as in terrestrial and avian species. The existing evidence of impact on these species is briefly discussed, as is the potential for some of them to serve as sentinel species for the ongoing monitoring needed to better understand potential effects, their potential causes, and to detect future changes. Quantification of the atmospheric emissions of multiple pollutants needs to be improved, as does an understanding of the processes influencing fugitive emissions and local and regional deposition patterns. The influence of multiple stressors on biota exposure and response, from natural bitumen and forest fires to climate change, complicates the current ability to attribute effects to air emissions from the industry. However, there is growing evidence of the impact of current levels of PACs on some species, pointing to the need to improve the ability to predict PAC exposures and the key emission source involved. Although this critical review attempts to integrate some of the findings across the components, in terms of ECCC activities, increased coordination or integration of air, water, and wildlife research would enhance deeper scientific understanding. Improved understanding is needed in order to guide the development of long-term monitoring strategies that could most efficiently inform a future adaptive management approach to oil sands environmental monitoring and prevention of impacts. Implications: Quantification of atmospheric emissions for multiple pollutants needs to be improved, and reporting mechanisms and standards could be adapted to facilitate such improvements, including periodic validation, particularly where uncertainties are the largest. Understanding of baseline conditions in the air, water and biota has improved significantly; ongoing enhanced monitoring, building on this progress, will help improve ecosystem protection measures in the oil sands region. Sentinel species have been identified that could be used to identify and characterize potential impacts of wildlife exposure, both locally and regionally. Polycyclic aromatic compounds are identified as having an impact on aquatic and terrestrial wildlife at current concentration levels although the significance of these impacts and attribution to emissions from oil sands development requires further assessment. Given the improvement in high resolution air quality prediction models, these should be a valuable tool to future environmental assessments and cumulative environment impact assessments.
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Affiliation(s)
- J R Brook
- a Dalla Lana School of Public Health and Department of Chemical Engineering and Applied Chemistry, University of Toronto , Toronto , Ontario , Canada
| | - S G Cober
- b Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario , Canada
| | - M Freemark
- c National Wildlife Research Centre, Environment and Climate Change, Ottawa , Canada
| | - T Harner
- b Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario , Canada
| | - S M Li
- b Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario , Canada
| | - J Liggio
- b Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario , Canada
| | - P Makar
- b Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario , Canada
| | - B Pauli
- c National Wildlife Research Centre, Environment and Climate Change, Ottawa , Canada
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15
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Liu Q, Liggio J, Breznan D, Thomson EM, Kumarathasan P, Vincent R, Li K, Li SM. Oxidative and Toxicological Evolution of Engineered Nanoparticles with Atmospherically Relevant Coatings. Environ Sci Technol 2019; 53:3058-3066. [PMID: 30794751 DOI: 10.1021/acs.est.8b06879] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The health impacts associated with engineered nanoparticles (ENPs) released into the atmosphere have not been adequately assessed. Such impacts could potentially arise from the toxicity associated with condensable atmospheric secondary organic material (SOM), or changes in the SOM composition induced by ENPs. Here, these possibilities are evaluated by investigating the oxidative and toxicological evolution of TiO2 and SiO2 nanoparticles which have been coated with SOM from the O3 or OH initiated oxidation of α-pinene. It was found that pristine SiO2 particles were significantly more cytotoxic compared to pristine TiO2 particles. TiO2 in the dark or under UV irradiation catalytically reacted with the SOM, increasing its O/C by up to 55% over photochemically inert SiO2 while having negligible effects on the overall cytotoxicity. Conversely, the cytotoxicity associated with SiO2 coated with SOM was markedly suppressed (by a factor of 9, at the highest exposure dose) with both increased SOM coating thickness and increased photochemical aging. These suppressing effects (organic coating and photo-oxidation of organics) were attributed to a physical hindrance of SiO2-cell interactions by the SOM and enhanced SOM viscosity and hydrophilicity with continued photo-oxidation, respectively. These findings highlight the importance of atmospheric processes in altering the cytotoxicity of ENPs.
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Affiliation(s)
- Qifan Liu
- Atmospheric Science and Technology Directorate , Science and Technology Branch, Environment Canada , 4905 Dufferin Street , Toronto , Ontario M3H 5T4 , Canada
| | - John Liggio
- Atmospheric Science and Technology Directorate , Science and Technology Branch, Environment Canada , 4905 Dufferin Street , Toronto , Ontario M3H 5T4 , Canada
| | - Dalibor Breznan
- Inhalation Toxicology Laboratory , Healthy Environments and Consumer Safety Branch, Health Canada , 0803C Tunney's Pasture , Ottawa , Ontario K1A 0K9 , Canada
| | - Errol M Thomson
- Inhalation Toxicology Laboratory , Healthy Environments and Consumer Safety Branch, Health Canada , 0803C Tunney's Pasture , Ottawa , Ontario K1A 0K9 , Canada
| | - Premkumari Kumarathasan
- Analytical Biochemistry and Proteomics Laboratory , Healthy Environments and Consumer Safety Branch, Health Canada , 0803C Tunney's Pasture , Ottawa , Ontario K1A 0K9 , Canada
| | - Renaud Vincent
- Inhalation Toxicology Laboratory , Healthy Environments and Consumer Safety Branch, Health Canada , 0803C Tunney's Pasture , Ottawa , Ontario K1A 0K9 , Canada
| | - Kun Li
- Atmospheric Science and Technology Directorate , Science and Technology Branch, Environment Canada , 4905 Dufferin Street , Toronto , Ontario M3H 5T4 , Canada
| | - Shao-Meng Li
- Atmospheric Science and Technology Directorate , Science and Technology Branch, Environment Canada , 4905 Dufferin Street , Toronto , Ontario M3H 5T4 , Canada
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16
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Liggio J, Stroud CA, Wentzell JJB, Zhang J, Sommers J, Darlington A, Liu PSK, Moussa SG, Leithead A, Hayden K, Mittermeier RL, Staebler R, Wolde M, Li SM. Quantifying the Primary Emissions and Photochemical Formation of Isocyanic Acid Downwind of Oil Sands Operations. Environ Sci Technol 2017; 51:14462-14471. [PMID: 29210280 DOI: 10.1021/acs.est.7b04346] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Isocyanic acid (HNCO) is a known toxic species and yet the relative importance of primary and secondary sources to regional HNCO and population exposure remains unclear. Off-road diesel fuel combustion has previously been suggested to be an important regional source of HNCO, which implies that major industrial facilities such as the oil sands (OS), which consume large quantities of diesel fuel, can be sources of HNCO. The OS emissions of nontraditional toxic species such as HNCO have not been assessed. Here, airborne measurements of HNCO were used to estimate primary and secondary HNCO for the oil sands. Approximately 6.2 ± 1.1 kg hr-1 was emitted from off-road diesel activities within oil sands facilities, and an additional 116-186 kg hr-1 formed from the photochemical oxidation of diesel exhaust. Together, the primary and secondary HNCO from OS operations represent a significant anthropogenic HNCO source in Canada. The secondary HNCO downwind of the OS was enhanced by up to a factor of 20 relative to its primary emission, an enhancement factor significantly greater than previously estimated from laboratory studies. Incorporating HNCO emissions and formation into a regional model demonstrated that the HNCO levels in Fort McMurray (∼10-70 km downwind of the OS) are controlled by OS emissions; > 50% of the monthly mean HNCO arose from the OS. While the mean HNCO levels in Fort McMurray are predicted to be below the 1000 pptv level associated with potential negative health impacts, (∼25 pptv in August-September), an order of magnitude increase in concentration is predicted (250-600 pptv) when the town is directly impacted by OS plumes. The results here highlight the importance of obtaining at-source HNCO emission factors and advancing the understanding of secondary HNCO formation mechanisms, to assess and improve HNCO population exposure predictions.
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Affiliation(s)
- John Liggio
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Craig A Stroud
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Jeremy J B Wentzell
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Junhua Zhang
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Jacob Sommers
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Andrea Darlington
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Peter S K Liu
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Samar G Moussa
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Amy Leithead
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Katherine Hayden
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Richard L Mittermeier
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Ralf Staebler
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
| | - Mengistu Wolde
- National Research Council Canada , Flight Research Laboratory, Ottawa, Ontario Canada , K1A 0R6
| | - Shao-Meng Li
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario Canada , M3H 5T4
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17
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Mungall EL, Abbatt JPD, Wentzell JJB, Lee AKY, Thomas JL, Blais M, Gosselin M, Miller LA, Papakyriakou T, Willis MD, Liggio J. Microlayer source of oxygenated volatile organic compounds in the summertime marine Arctic boundary layer. Proc Natl Acad Sci U S A 2017; 114:6203-6208. [PMID: 28559340 PMCID: PMC5474767 DOI: 10.1073/pnas.1620571114] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Summertime Arctic shipboard observations of oxygenated volatile organic compounds (OVOCs) such as organic acids, key precursors of climatically active secondary organic aerosol (SOA), are consistent with a novel source of OVOCs to the marine boundary layer via chemistry at the sea surface microlayer. Although this source has been studied in a laboratory setting, organic acid emissions from the sea surface microlayer have not previously been observed in ambient marine environments. Correlations between measurements of OVOCs, including high levels of formic acid, in the atmosphere (measured by an online high-resolution time-of-flight mass spectrometer) and dissolved organic matter in the ocean point to a marine source for the measured OVOCs. That this source is photomediated is indicated by correlations between the diurnal cycles of the OVOC measurements and solar radiation. In contrast, the OVOCs do not correlate with levels of isoprene, monoterpenes, or dimethyl sulfide. Results from box model calculations are consistent with heterogeneous chemistry as the source of the measured OVOCs. As sea ice retreats and dissolved organic carbon inputs to the Arctic increase, the impact of this source on the summer Arctic atmosphere is likely to increase. Globally, this source should be assessed in other marine environments to quantify its impact on OVOC and SOA burdens in the atmosphere, and ultimately on climate.
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Affiliation(s)
- Emma L Mungall
- Department of Chemistry, University of Toronto, Toronto, ON, Canada ON M5S 3H6
| | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, Toronto, ON, Canada ON M5S 3H6;
| | - Jeremy J B Wentzell
- Air Quality Processes Research Section, Environment Canada, Toronto, ON, Canada M3H 5T4
| | - Alex K Y Lee
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
| | - Jennie L Thomas
- Sorbonne Universités, Pierre and Marie Curie University, Université Versailles St-Quentin, CNRS, Institut National des Sciences de l'Univers, Laboratoire Atmosphères, Milieux, Observations Spatiales, Institut Pierre Simon Laplace, 75252 Paris, France
| | - Marjolaine Blais
- Institut des Sciences de la Mer de Rimouski (Québec-Océan), Université du Québec à Rimouski, Rimouski, QC, Canada G5L 3A1
| | - Michel Gosselin
- Institut des Sciences de la Mer de Rimouski (Québec-Océan), Université du Québec à Rimouski, Rimouski, QC, Canada G5L 3A1
| | - Lisa A Miller
- Institute of Ocean Sciences, Fisheries and Oceans Canada, Sidney, BC, Canada V8L 4B2
| | - Tim Papakyriakou
- Centre for Earth Observation Science, Faculty of Environment, Earth and Resources, University of Manitoba, Winnipeg, MB, Canada R3T 2N2
| | - Megan D Willis
- Department of Chemistry, University of Toronto, Toronto, ON, Canada ON M5S 3H6
| | - John Liggio
- Air Quality Processes Research Section, Environment Canada, Toronto, ON, Canada M3H 5T4
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Li SM, Leithead A, Moussa SG, Liggio J, Moran MD, Wang D, Hayden K, Darlington A, Gordon M, Staebler R, Makar PA, Stroud CA, McLaren R, Liu PSK, O'Brien J, Mittermeier RL, Zhang J, Marson G, Cober SG, Wolde M, Wentzell JJB. Differences between measured and reported volatile organic compound emissions from oil sands facilities in Alberta, Canada. Proc Natl Acad Sci U S A 2017; 114:E3756-E3765. [PMID: 28439021 PMCID: PMC5441713 DOI: 10.1073/pnas.1617862114] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Large-scale oil production from oil sands deposits in Alberta, Canada has raised concerns about environmental impacts, such as the magnitude of air pollution emissions. This paper reports compound emission rates (E) for 69-89 nonbiogenic volatile organic compounds (VOCs) for each of four surface mining facilities, determined with a top-down approach using aircraft measurements in the summer of 2013. The aggregate emission rate (aE) of the nonbiogenic VOCs ranged from 50 ± 14 to 70 ± 22 t/d depending on the facility. In comparison, equivalent VOC emission rates reported to the Canadian National Pollutant Release Inventory (NPRI) using accepted estimation methods were lower than the aE values by factors of 2.0 ± 0.6, 3.1 ± 1.1, 4.5 ± 1.5, and 4.1 ± 1.6 for the four facilities, indicating underestimation in the reported VOC emissions. For 11 of the combined 93 VOC species reported by all four facilities, the reported emission rate and E were similar; but for the other 82 species, the reported emission rate was lower than E The median ratio of E to that reported for all species by a facility ranged from 4.5 to 375 depending on the facility. Moreover, between 9 and 53 VOCs, for which there are existing reporting requirements to the NPRI, were not included in the facility emission reports. The comparisons between the emission reports and measurement-based emission rates indicate that improvements to VOC emission estimation methods would enhance the accuracy and completeness of emission estimates and their applicability to environmental impact assessments of oil sands developments.
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Affiliation(s)
- Shao-Meng Li
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4;
| | - Amy Leithead
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Samar G Moussa
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - John Liggio
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Michael D Moran
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Daniel Wang
- Air Quality Research Division, Environment and Climate Change Canada, Ottawa, ON, Canada K1A 0H3
| | - Katherine Hayden
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Andrea Darlington
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Mark Gordon
- Centre for Research in Earth and Space Science, York University, Toronto, ON, Canada M3J 1P3
| | - Ralf Staebler
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Paul A Makar
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Craig A Stroud
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Robert McLaren
- Centre for Atmospheric Chemistry, York University, Toronto, ON, Canada M3J 1P3
| | - Peter S K Liu
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Jason O'Brien
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Richard L Mittermeier
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Junhua Zhang
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - George Marson
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Stewart G Cober
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
| | - Mengistu Wolde
- Flight Research Laboratory, National Research Council Canada, Ottawa, ON, Canada K1A 0R6
| | - Jeremy J B Wentzell
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, ON, Canada M3H 5T4
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Li K, Li J, Liggio J, Wang W, Ge M, Liu Q, Guo Y, Tong S, Li J, Peng C, Jing B, Wang D, Fu P. Enhanced Light Scattering of Secondary Organic Aerosols by Multiphase Reactions. Environ Sci Technol 2017; 51:1285-1292. [PMID: 28052190 DOI: 10.1021/acs.est.6b03229] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Secondary organic aerosol (SOA) plays a pivotal role in visibility and radiative forcing, both of which are intrinsically linked to the refractive index (RI). While previous studies have focused on the RI of SOA from traditional formation processes, the effect of multiphase reactions on the RI has not been considered. Here, we investigate the effects of multiphase processes on the RI and light-extinction of m-xylene-derived SOA, a common type of anthropogenic SOA. We find that multiphase reactions in the presence of liquid water lead to the formation of oligomers from intermediate products such as glyoxal and methylglyoxal, resulting in a large enhancement in the RI and light-scattering of this SOA. These reactions will result in increases in light-scattering efficiency and direct radiative forcing of approximately 20%-90%. These findings improve our understanding of SOA optical properties and have significant implications for evaluating the impacts of SOA on the rapid formation of regional haze, global radiative balance, and climate change.
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Affiliation(s)
- Kun Li
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
| | - Junling Li
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
| | - John Liggio
- Air Quality Research Division, Environment and Climate Change Canada , Toronto, Ontario M3H 5T4, Canada
| | - Weigang Wang
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
| | - Maofa Ge
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
- CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences , Xiamen 361021, P. R. China
| | - Qifan Liu
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
| | - Yucong Guo
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
| | - Shengrui Tong
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
| | - Jiangjun Li
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
- Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
| | - Chao Peng
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
| | - Bo Jing
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
| | - Dong Wang
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
- Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China
| | - Pingqing Fu
- University of Chinese Academy of Sciences , Beijing 100049, P. R. China
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics, Chinese Academy of Sciences , Beijing 100029, China
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20
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Chu B, Liggio J, Liu Y, He H, Takekawa H, Li SM, Hao J. Influence of metal-mediated aerosol-phase oxidation on secondary organic aerosol formation from the ozonolysis and OH-oxidation of α-pinene. Sci Rep 2017; 7:40311. [PMID: 28059151 PMCID: PMC5216392 DOI: 10.1038/srep40311] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 12/02/2016] [Indexed: 12/12/2022] Open
Abstract
The organic component is the most abundant fraction of atmospheric submicron particles, while the formation mechanisms of secondary organic aerosol (SOA) are not fully understood. The effects of sulfate seed aerosols on SOA formation were investigated with a series of experiments carried out using a 9 m3 smog chamber. The presence of FeSO4 or Fe2(SO4)3 seed aerosols decreased SOA yields and increased oxidation levels in both ozonolysis and OH-oxidation of α-pinene compared to that in the presence of ZnSO4 or (NH4)2SO4. These findings were explained by metal-mediated aerosol-phase oxidation of organics: reactive radicals were generated on FeSO4 or Fe2(SO4)3 seed aerosols and reacted further with the organic mass. This effect would help to explain the high O/C ratios of organics in ambient particles that thus far cannot be reproduced in laboratory and model studies. In addition, the gap in the SOA yields between experiments with different seed aerosols was more significant in OH-oxidation experiments compared to ozonolysis experiments, while the gap in estimated O/C ratios was less obvious. This may have resulted from the different chemical compositions and oxidation levels of the SOA generated in the two systems, which affect the branching ratio of functionalization and fragmentation during aerosol oxidation.
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Affiliation(s)
- Biwu Chu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.,Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - John Liggio
- Air Quality Research Division, Environment Canada, Toronto, Ontario M3H5T4, Canada
| | - Yongchun Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.,Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.,Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hideto Takekawa
- Toyota Central Research and Development Laboratory, Nagakute, Aichi 480-1192, Japan
| | - Shao-Meng Li
- Air Quality Research Division, Environment Canada, Toronto, Ontario M3H5T4, Canada
| | - Jiming Hao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
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Liggio J, Li SM, Hayden K, Taha YM, Stroud C, Darlington A, Drollette BD, Gordon M, Lee P, Liu P, Leithead A, Moussa SG, Wang D, O’Brien J, Mittermeier RL, Brook JR, Lu G, Staebler RM, Han Y, Tokarek TW, Osthoff HD, Makar PA, Zhang J, L. Plata D, Gentner DR. Oil sands operations as a large source of secondary organic aerosols. Nature 2016; 534:91-4. [DOI: 10.1038/nature17646] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 03/02/2016] [Indexed: 11/09/2022]
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Liu Y, Liggio J, Li SM, Breznan D, Vincent R, Thomson EM, Kumarathasan P, Das D, Abbatt J, Antiñolo M, Russell L. Chemical and toxicological evolution of carbon nanotubes during atmospherically relevant aging processes. Environ Sci Technol 2015; 49:2806-14. [PMID: 25607982 DOI: 10.1021/es505298d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The toxicity of carbon nanotubes (CNTs) has received significant attention due to their usage in a wide range of commercial applications. While numerous studies exist on their impacts in water and soil ecosystems, there is a lack of information on the exposure to CNTs from the atmosphere. The transformation of CNTs in the atmosphere, resulting in their functionalization, may significantly alter their toxicity. In the current study, the chemical modification of single wall carbon nanotubes (SWCNTs) via ozone and OH radical oxidation is investigated through studies that simulate a range of expected tropospheric particulate matter (PM) lifetimes, in order to link their chemical evolution to toxicological changes. The results indicate that the oxidation favors carboxylic acid functionalization, but significantly less than other studies performed under nonatmospheric conditions. Despite evidence of functionalization, neither O3 nor OH radical oxidation resulted in a change in redox activity (potentially giving rise to oxidative stress) or in cytotoxic end points. Conversely, both the redox activity and cytotoxicity of SWCNTs significantly decreased when exposed to ambient urban air, likely due to the adsorption of organic carbon vapors. These results suggest that the effect of gas-particle partitioning of organics in the atmosphere on the toxicity of SWCNTs should be investigated further.
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Affiliation(s)
- Yongchun Liu
- Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment Canada , 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
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Chu B, Liu Y, Li J, Takekawa H, Liggio J, Li SM, Jiang J, Hao J, He H. Decreasing effect and mechanism of FeSO4 seed particles on secondary organic aerosol in α-pinene photooxidation. Environ Pollut 2014; 193:88-93. [PMID: 25014016 DOI: 10.1016/j.envpol.2014.06.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 06/11/2014] [Accepted: 06/12/2014] [Indexed: 06/03/2023]
Abstract
α-Pinene/NOx and α-pinene/HONO photooxidation experiments at varying humidity were conducted in smog chambers in the presence or absence of FeSO4 seed particles. FeSO4 seed particles decrease SOA mass as long as water was present on the seed particle surface, but FeSO4 seed particles have no decreasing effect on SOA under dryer conditions at 12% relative humidity (RH). The decreasing effect of FeSO4 seed particles on the SOA mass is proposed to be related to oxidation processes in the surface layer of water on the seed particles. Free radicals, including OH, can be formed from catalytic cycling of Fe(2+) and Fe(3+) in the aqueous phase. These radicals can react further with the organic products of α-pinene oxidation on the seed particles. The oxidation may lead to formation of smaller molecules which have higher saturation vapor pressures and favor repartitioning to the gas phase, and therefore, reduces SOA mass.
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Affiliation(s)
- Biwu Chu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Yongchun Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Air Quality Research Division, Environment Canada, Toronto, Ontario, Canada
| | - Junhua Li
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Hideto Takekawa
- Toyota Central Research and Development Laboratory, Nagakute, Aichi 480-1192, Japan
| | - John Liggio
- Air Quality Research Division, Environment Canada, Toronto, Ontario, Canada
| | - Shao-Meng Li
- Air Quality Research Division, Environment Canada, Toronto, Ontario, Canada
| | - Jingkun Jiang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Jiming Hao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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Liu Y, Liggio J, Harner T, Jantunen L, Shoeib M, Li SM. Heterogeneous OH initiated oxidation: a possible explanation for the persistence of organophosphate flame retardants in air. Environ Sci Technol 2014; 48:1041-8. [PMID: 24364718 DOI: 10.1021/es404515k] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Heterogeneous reactions between OH radicals and emerging flame retardant compounds coated on inert particles have been investigated. Organophosphate esters (OPEs) including triphenyl phosphate (TPhP), tris-2-ethylhexyl phosphate (TEHP), and tris-1,3-dichloro-2-propyl phosphate (TDCPP) were coated on (NH4)2SO4 particles and exposed to OH radicals in a photochemical flow tube at 298 K and (38.0 ± 2.0) % RH. The degradation of these particle-bound OPEs was observed as a result of OH exposure, as measured using a Time-of-Flight Aerosol Mass Spectrometer. The derived second-order rate constants for the heterogeneous loss of TPhP, TEHP, and TDCPP were (2.1 ± 0.19) × 10(-12), (2.7 ± 0.63) × 10(-12), and (9.2 ± 0.92) × 10(-13) cm(3) molecule(-1) s(-1), respectively, from which approximate atmospheric lifetimes are estimated to be 5.6 (5.2-6.0), 4.3 (3.5-5.6), and 13 (11-14) days. Additional coating of the OPE coated particles with an OH radical active species further increased the lifetimes of these OPEs. These results represent the first reported estimates of heterogeneous reaction rate constants for these species. The results demonstrate that particle bound OPEs are highly persistent in the atmosphere with regard to OH radical oxidation, consistent with the assumption that OPEs can undergo medium or long-range transport, as previously proposed on the basis of field measurements. Finally, these results indicate that future risk assessment and transport modeling of emerging priority chemicals with semi- to low-volatility must consider particle phase heterogeneous loss processes when evaluating environmental persistence.
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Affiliation(s)
- Yongchun Liu
- Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment Canada , Toronto, M3H 5T4, Canada
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Lee AKY, Zhao R, Li R, Liggio J, Li SM, Abbatt JPD. Formation of light absorbing organo-nitrogen species from evaporation of droplets containing glyoxal and ammonium sulfate. Environ Sci Technol 2013; 47:12819-12826. [PMID: 24156773 DOI: 10.1021/es402687w] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In the atmosphere, volatile organic compounds such as glyoxal can partition into aqueous droplets containing significant levels of inorganic salts. Upon droplet evaporation, both the organics and inorganic ions become highly concentrated, accelerating reactions between them. To demonstrate this process, we investigated the formation of organo-nitrogen and light absorbing materials in evaporating droplets containing glyoxal and different ammonium salts including (NH4)2SO4, NH4NO3, and NH4Cl. Our results demonstrate that evaporating glyoxal-(NH4)2SO4 droplets produce light absorbing species on a time scale of seconds, which is orders of magnitude faster than observed in bulk solutions. Using aerosol mass spectrometry, we show that particle-phase organics with high N:C ratios were formed when ammonium salts were used, and that the presence of sulfate ions promoted this chemistry. Since sulfate can also significantly enhance the Henry's law partitioning of glyoxal, our results highlight the atmospheric importance of such inorganic-organic interactions in aqueous phase aerosol chemistry.
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Affiliation(s)
- Alex K Y Lee
- Department of Chemistry, University of Toronto , Toronto, Canada
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Wentzell JJB, Liggio J, Li SM, Vlasenko A, Staebler R, Lu G, Poitras MJ, Chan T, Brook JR. Measurements of gas phase acids in diesel exhaust: a relevant source of HNCO? Environ Sci Technol 2013; 47:7663-7671. [PMID: 23781923 DOI: 10.1021/es401127j] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Gas-phase acids in light duty diesel (LDD) vehicle exhaust were measured using chemical ionization mass spectrometry (CIMS). Fuel based emission factors (EF) and NOx ratios for these species were determined under differing steady state engine operating conditions. The derived HONO and HNO3 EFs agree well with literature values, with HONO being the single most important acidic emission. Of particular importance is the quantification of the EF for the toxic species, isocyanic acid (HNCO). The emission factors for HNCO ranged from 0.69 to 3.96 mg kgfuel(-1), and were significantly higher than previous biomass burning emission estimates. Further ambient urban measurements of HNCO demonstrated a clear relationship with the known traffic markers of benzene and toluene, demonstrating for the first time that urban commuter traffic is a source of HNCO. Estimates based upon the HNCO-benzene relationship indicate that upward of 23 tonnes of HNCO are released annually from commuter traffic in the Greater Toronto Area, far exceeding the amount possible from LDD alone. Nationally, 250 to 770 tonnes of HNCO may be emitted annually from on-road vehicles, likely representing the dominant source of exposure in urban areas, and with emissions comparable to that of biomass burning.
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Affiliation(s)
- Jeremy J B Wentzell
- Air Quality Processes Research Section, Environment Canada , 4905 Dufferin Street, Toronto, Ontario, Canada M3H 5T4
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McWhinney RD, Badali K, Liggio J, Li SM, Abbatt JPD. Filterable redox cycling activity: a comparison between diesel exhaust particles and secondary organic aerosol constituents. Environ Sci Technol 2013; 47:3362-9. [PMID: 23470039 DOI: 10.1021/es304676x] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The redox activity of diesel exhaust particles (DEP) collected from a light-duty diesel passenger car engine was examined using the dithiothreitol (DTT) assay. DEP was highly redox-active, causing DTT to decay at a rate of 23-61 pmol min(-1) μg(-1) of particle used in the assay, which was an order of magnitude higher than ambient coarse and fine particulate matter (PM) collected from downtown Toronto. Only 2-11% of the redox activity was in the water-soluble portion, while the remainder occurred at the black carbon surface. This is in contrast to redox-active secondary organic aerosol constituents, in which upward of 90% of the activity occurs in the water-soluble fraction. The redox activity of DEP is not extractable by moderately polar (methanol) and nonpolar (dichloromethane) organic solvents, and is hypothesized to arise from redox-active moieties contiguous with the black carbon portion of the particles. These measurements illustrate that "Filterable Redox Cycling Activity" may therefore be useful to distinguish black carbon-based oxidative capacity from water-soluble organic-based activity. The difference in chemical environment leading to redox activity highlights the need to further examine the relationship between activity in the DTT assay and toxicology measurements across particles of different origins and composition.
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Affiliation(s)
- Robert D McWhinney
- Department of Chemistry, University of Toronto, 80 St George Street, Toronto, Ontario, Canada.
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Liggio J, Gordon M, Smallwood G, Li SM, Stroud C, Staebler R, Lu G, Lee P, Taylor B, Brook JR. Are emissions of black carbon from gasoline vehicles underestimated? Insights from near and on-road measurements. Environ Sci Technol 2012; 46:4819-28. [PMID: 22309316 DOI: 10.1021/es2033845] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Measurements of black carbon (BC) with a high-sensitivity laser-induced incandescence (HS-LII) instrument and a single particle soot photometer (SP2) were conducted upwind, downwind, and while driving on a highway dominated by gasoline vehicles. The results are used with concurrent CO(2) measurements to derive fuel-based BC emission factors for real-world average fleet and heavy-duty diesel vehicles separately. The derived emission factors from both instruments are compared, and a low SP2 bias (relative to the HS-LII) is found to be caused by a BC mass mode diameter less than 75 nm, that is most prominent with the gasoline fleet but is not present in the heavy-duty diesel vehicle exhaust on the highway. Results from both the LII and the SP2 demonstrate that the BC emission factors from gasoline vehicles are at least a factor of 2 higher than previous North American measurements, and a factor of 9 higher than currently used emission inventories in Canada, derived with the MOBILE 6.2C model. Conversely, the measured BC emission factor for heavy-duty diesel vehicles is in reasonable agreement with previous measurements. The results suggest that greater attention must be paid to black carbon from gasoline engines to obtain a full understanding of the impact of black carbon on air quality and climate and to devise appropriate mitigation strategies.
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Affiliation(s)
- John Liggio
- Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4 Canada.
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Liggio J, Li SM, Vlasenko A, Stroud C, Makar P. Depression of ammonia uptake to sulfuric acid aerosols by competing uptake of ambient organic gases. Environ Sci Technol 2011; 45:2790-2796. [PMID: 21405082 DOI: 10.1021/es103801g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The neutralization of acidic aerosols by ammonia has been studied through experiments which combine ambient air with laboratory generated sulfuric acid aerosol. Results indicated that acidic aerosol mixed with organic free air and ammonia was neutralized on a time scale<1 min, consistent with expectations. However, in the presence of ambient organic gases and ammonia, the rate of aerosol neutralization is significantly reduced. This reduction in ammonia uptake was concurrent with an increase in the amount of particle phase organics. A steady state in the NH4+/SO4(2-) in the presence of organic gases was established on time scales of 10 min to several hours, corresponding to NH3 uptake coefficients in the range of 4×10(-3)-2×10(-4). The degree to which neutralization was slowed was dependent upon the initial ammonia concentration and the organic mass added to the aerosols. These results suggest that inorganic equilibrium thermodynamic models may overestimate the rate of ammonia uptake and that ambient particles may remain acidic for longer than previously expected.
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Affiliation(s)
- John Liggio
- Atmospheric Science and Technology Directorate, Science and Technology Branch, Environment Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada.
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Liggio J, Li SM, Vlasenko A, Sjostedt S, Chang R, Shantz N, Abbatt J, Slowik JG, Bottenheim JW, Brickell PC, Stroud C, Leaitch WR. Primary and secondary organic aerosols in urban air masses intercepted at a rural site. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010jd014426] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Liggio J, Li SM, McLaren R. Heterogeneous reactions of glyoxal on particulate matter: identification of acetals and sulfate esters. Environ Sci Technol 2005; 39:1532-41. [PMID: 15819206 DOI: 10.1021/es048375y] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Reactive uptake of glyoxal onto particulate matter has been studied in laboratory experiments in a 2 m3 Teflon reaction chamber. Inorganic seed particles of different composition were utilized, including (NH4)2SO4, (NH4)2SO4/ H2SO4, NaNO3, and simulated sea salt, while the relative humidity and acid concentration were varied. The organic composition of the growing particles was measured in situ with an aerosol mass spectrometer, providing particle mass spectra as a means of product identification. Aerosol physical characteristics were also measured with a differential mobility analyzer and condensation nucleus counter. Regardless of seed composition, particle growth was rapid and continuous over the course of several hours. Identification of several mass fragments greater than the glyoxal monomer suggested that heterogeneous reactionsto form glyoxal adducts of lowvolatility had occurred. Temporal analysis of the mass fragments was consistent with a proposed acid-catalyzed mechanism whereby glyoxal is first hydrated, followed by self-reaction to form cyclic acetal structures. Increased relative humidity slowed the formation of higher order oligomers, also consistent with the proposed mechanism. The relative contribution of various oligomers to the overall organic composition was strongly dependent on the relative humidity and hence the particulate water concentration. A mild acid catalysis was also observed upon increasing the acidity of the seed particles. Specific mass fragments were found that could only arise from sulfate esters and were not present on the non-sulfur-containing seed particles. This first evidence of the formation of organic sulfates in particles is presented together with a proposed mechanism and molecular structure. These results suggest that the formation of these products of glyoxal uptake can contribute significantly to secondary organic aerosol.
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Affiliation(s)
- John Liggio
- Centre for Atmospheric Chemistry and Chemistry Department, York University, Toronto, Ontario, M3J 1P3 Canada
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