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Downey JP, Lakey PSJ, Shiraiwa M, Abbatt JPD. Ozone Loss on Painted Surfaces: Dependence on Relative Humidity, Aging, and Exposure to Reactive SVOCs. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:12073-12081. [PMID: 38923518 DOI: 10.1021/acs.est.4c02208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
Ozone and its oxidation products result in negative health effects when inhaled. Despite painted surfaces being the most abundant surface in indoor spaces, surface loss remains one of the largest uncertainties in the indoor ozone budget. Here, ozone uptake coefficients (γO3) on painted surfaces were measured in a flow-through reactor where 79% of the inner surfaces were removable painted glass sheets. Flat white paint initially had a high uptake coefficient (8.3 × 10-6) at 20% RH which plateaued to 1.1 × 10-6 as the paint aged in an indoor office over weeks. Increasing the RH from 0 to 75% increased γO3 by a factor of 3.0, and exposure to 134 ppb of α-terpineol for 1 h increased γO3 by a factor of 1.6 at 20% RH. RH also increases α-terpineol partitioning to paint, further increasing ozone loss, but the type of paint (flat, eggshell, satin, semigloss) had no significant effect. A kinetic multilayer model captures the dependence of γO3 on RH and the presence of α-terpineol, indicating the reacto-diffusive depth for O3 is 1 to 2 μm. Given the similarity of the kinetics on aged surfaces across many paint types and the sustained reactivity during aging, these results suggest a mechanism for catalytic loss.
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Affiliation(s)
- Jillian P Downey
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Pascale S J Lakey
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Manabu Shiraiwa
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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2
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Cummings BE, Lakey PSJ, Morrison GC, Shiraiwa M, Waring MS. Composition of indoor organic surface films in residences: simulating the influence of sources, partitioning, particle deposition, and air exchange. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024; 26:305-322. [PMID: 38108243 DOI: 10.1039/d3em00399j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Indoor surfaces are coated with organic films that modulate thermodynamic interactions between the surfaces and room air. Recently published models can simulate film formation and growth via gas-surface partitioning, but none have statistically investigated film composition. The Indoor Model of Aerosols, Gases, Emissions, and Surfaces (IMAGES) was used here to simulate ten years of nonreactive film growth upon impervious indoor surfaces within a Monte Carlo procedure representing a sub-set of North American residential buildings. Film composition was resolved into categories reflecting indoor aerosol (gas + particle phases) factors from three sources: outdoor-originating, indoor-emitted, and indoor-generated secondary organic material. In addition to gas-to-film partitioning, particle deposition was modeled as a vector for organics to enter films, and it was responsible for a majority of the film mass after ∼1000 days of growth for the median simulation and is likely the main source of LVOCs within films. Therefore, the organic aerosol factor possessing the most SVOCs contributes most strongly to the composition of early films, but as the film ages, films become more dominated by the factor with the highest particle concentration. Indoor-emitted organics (e.g. from cooking) often constituted at least a plurality of the simulated mass in developed films, but indoor environments are diverse enough that any major organic material source could be the majority contributor to film mass, depending on building characteristics and indoor activities. A sensitivity analysis suggests that rapid film growth is most likely in both newer, more air-tight homes and older homes near primary pollution sources.
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3
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Wu S, Kim E, Zhao R. Acetal Formation of Flavoring Agents with Propylene Glycol in E-Cigarettes: Impacts on Indoor Partitioning and Thirdhand Exposure. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:21284-21294. [PMID: 38065550 DOI: 10.1021/acs.est.3c08514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
The widespread use of flavored e-cigarettes has led to a significant rise in teenage nicotine use. In e-liquids, the flavor carbonyls can form acetals with unknown chemical and toxicological properties. These acetals can cause adverse health effects on both smokers and nonsmokers through thirdhand exposure. This study aims to explore the impacts of these acetals formed in e-cigarettes on indoor partitioning and thirdhand exposure. Specifically, the acetalization reactions of commonly used flavor carbonyls in laboratory-made e-liquids were monitored using proton nuclear magnetic resonance (1H NMR) spectroscopy. EAS-E Suite and polyparameter linear free energy relationships (PP-LFERs) were employed to estimate the partitioning coefficients for species. Further, a chemical two-dimensional partitioning model was applied to visualize the indoor equilibrium partitioning and estimate the distribution of flavor carbonyls and their acetals in the gas phase, aerosol phase, and surface reservoirs. Our results demonstrate that a substantial fraction of carbonyls were converted into acetals in e-liquids and their chemical partitioning was significantly influenced. This study shows that acetalization is a determinant factor in the exposure and toxicology of harmful carbonyl flavorings, with its impact extending to both direct exposure to smokers and involuntary exposure to nonsmokers.
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Affiliation(s)
- Shuang Wu
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Erica Kim
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Ran Zhao
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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4
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Li J, Link MF, Pandit S, Webb MH, Mayer KJ, Garofalo LA, Rediger KL, Poppendieck DG, Zimmerman SM, Vance ME, Grassian VH, Morrison GC, Turpin BJ, Farmer DK. The persistence of smoke VOCs indoors: Partitioning, surface cleaning, and air cleaning in a smoke-contaminated house. SCIENCE ADVANCES 2023; 9:eadh8263. [PMID: 37831770 PMCID: PMC10575580 DOI: 10.1126/sciadv.adh8263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 09/12/2023] [Indexed: 10/15/2023]
Abstract
Wildfires are increasing in frequency, raising concerns that smoke can permeate indoor environments and expose people to chemical air contaminants. To study smoke transformations in indoor environments and evaluate mitigation strategies, we added smoke to a test house. Many volatile organic compounds (VOCs) persisted days following the smoke injection, providing a longer-term exposure pathway for humans. Two time scales control smoke VOC partitioning: a faster one (1.0 to 5.2 hours) that describes the time to reach equilibrium between adsorption and desorption processes and a slower one (4.8 to 21.2 hours) that describes the time for indoor ventilation to overtake adsorption-desorption equilibria in controlling the air concentration. These rates imply that vapor pressure controls partitioning behavior and that house ventilation plays a minor role in removing smoke VOCs. However, surface cleaning activities (vacuuming, mopping, and dusting) physically removed surface reservoirs and thus reduced indoor smoke VOC concentrations more effectively than portable air cleaners and more persistently than window opening.
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Affiliation(s)
- Jienan Li
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA
| | - Michael F. Link
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Shubhrangshu Pandit
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
| | - Marc H. Webb
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Kathryn J. Mayer
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA
| | - Lauren A. Garofalo
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA
| | - Katelyn L. Rediger
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA
| | | | | | - Marina E. Vance
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Vicki H. Grassian
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
| | - Glenn C. Morrison
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Barbara J. Turpin
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Delphine K. Farmer
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA
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Lakey PSJ, Cummings BE, Waring MS, Morrison GC, Shiraiwa M. Effective mass accommodation for partitioning of organic compounds into surface films with different viscosities. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:1464-1478. [PMID: 37560969 DOI: 10.1039/d3em00213f] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
Indoor surfaces can act as reservoirs and reaction media influencing the concentrations and type of species that people are exposed to indoors. Mass accommodation and partitioning are impacted by the phase state and viscosity of indoor surface films. We developed the kinetic multi-layer model KM-FILM to simulate organic film formation and growth, but it is computationally expensive to couple such comprehensive models with indoor air box models. Recently, a novel effective mass accommodation coefficient (αeff) was introduced for efficient and effective treatments of gas-particle partitioning. In this study, we extended this approach to a film geometry with αeff as a function of penetration depth into the film, partitioning coefficient, bulk diffusivity, and condensed-phase reaction rate constant. Comparisons between KM-FILM and the αeff method show excellent agreement under most conditions, but with deviations before the establishment of quasi-equilibrium within the penetration depth. We found that the deposition velocity of species and overall film growth are impacted by bulk diffusivity in highly viscous films (Db ∼<10-15 cm2 s-1). Reactions that lead to non-volatile products can increase film thicknesses significantly, with the extent of film growth being dependent on the gas-phase concentration, rate coefficient, partitioning coefficient and diffusivity. Amorphous semisolid films with Db > ∼10-17-10-19 cm2 s-1 can be efficient SVOC reservoirs for compounds with higher partitioning coefficients as they can be released back to the gas phase over extended periods of time, while glassy solid films would not be able to act as reservoirs as gas-film partitioning is impeded.
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Affiliation(s)
- Pascale S J Lakey
- Department of Chemistry, University of California, Irvine, CA 92697, USA.
| | - Bryan E Cummings
- Department of Civil, Architectural and Environmental Engineering, Drexel University, PA 19104, USA
| | - Michael S Waring
- Department of Civil, Architectural and Environmental Engineering, Drexel University, PA 19104, USA
| | - Glenn C Morrison
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC, USA
| | - Manabu Shiraiwa
- Department of Chemistry, University of California, Irvine, CA 92697, USA.
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Cao C, Gentner DR, Commane R, Toledo-Crow R, Schiferl LD, Mak JE. Policy-Related Gains in Urban Air Quality May Be Offset by Increased Emissions in a Warming Climate. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37327457 DOI: 10.1021/acs.est.2c05904] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Air quality policies have made substantial gains by reducing pollutant emissions from the transportation sector. In March 2020, New York City's activities were severely curtailed in response to the COVID-19 pandemic, resulting in 60-90% reductions in human activity. We continuously measured major volatile organic compounds (VOCs) during January-April 2020 and 2021 in Manhattan. Concentrations of many VOCs decreased significantly during the shutdown with variations in daily patterns reflective of human activity perturbations, resulting in a temporary ∼28% reduction in chemical reactivity. However, the limited effect of these dramatic measures was outweighed by larger increases in VOC-related reactivity during the anomalously warm spring 2021. This emphasizes the diminishing returns from transportation-focused policies alone and the risk of increased temperature-dependent emissions undermining policy-related gains in a warming climate.
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Affiliation(s)
- Cong Cao
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794, United States
| | - Drew R Gentner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
| | - Róisín Commane
- Department of Earth and Environmental Sciences, Columbia University, New York, New York 10027, United States
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, United States
| | - Ricardo Toledo-Crow
- Advanced Science Research Center, City University of New York, New York, New York 10031, United States
| | - Luke D Schiferl
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, United States
| | - John E Mak
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794, United States
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7
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Laguerre A, Gall ET. Measurement of Polycyclic Aromatic Hydrocarbons (PAHs) on Indoor Materials: Method Development. ACS OMEGA 2023; 8:20634-20641. [PMID: 37332781 PMCID: PMC10268631 DOI: 10.1021/acsomega.3c01184] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 05/12/2023] [Indexed: 06/20/2023]
Abstract
Wildfire smoke penetrates indoors, and polycyclic aromatic hydrocarbons (PAHs) in smoke may accumulate on indoor materials. We developed two approaches for measuring PAHs on common indoor materials: (1) solvent-soaked wiping of solid materials (glass and drywall) and (2) direct extraction of porous/fleecy materials (mechanical air filter media and cotton sheets). Samples are extracted by sonication in dichloromethane and analyzed with gas chromatography-mass spectrometry. Extraction recoveries range from 50-83% for surrogate standards and for PAHs recovered from direct application to isopropanol-soaked wipes, in line with prior studies. We evaluate our methods with a total recovery metric, defined as the sampling and extraction recovery of PAHs from a test material spiked with known PAH mass. Total recovery is higher for "heavy" PAHs (HPAHs, 4 or more aromatic rings) than for "light" PAHs (LPAHs, 2-3 aromatic rings). For glass, the total recovery range is 44-77% for HPAHs and 0-30% for LPAHs. Total recoveries from painted drywall are <20% for all PAHs tested. For filter media and cotton, total recoveries of HPAHs are 37-67 and 19-57%, respectively. These data show acceptable HPAH total recovery on glass, cotton, and filter media; total recovery of LPAHs may be unacceptably low for indoor materials using methods developed here. Our data also indicate that extraction recovery of surrogate standards may overestimate the total recovery of PAHs from glass using solvent wipe sampling. The developed method enables future studies of accumulation of PAHs indoors, including potential longer-term exposure derived from contaminated indoor surfaces.
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Salthammer T, Hohm U, Stahn M, Grimme S. Proton-transfer rate constants for the determination of organic indoor air pollutants by online mass spectrometry. RSC Adv 2023; 13:17856-17868. [PMID: 37323443 PMCID: PMC10262294 DOI: 10.1039/d3ra01705b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 06/06/2023] [Indexed: 06/17/2023] Open
Abstract
Proton transfer reaction mass spectrometry (PTR-MS) has become an indispensable analytical tool for indoor related sciences. With high-resolution techniques not only is the online monitoring of the selected ions in the gas phase possible, but also, with some limitations, the identification of substance mixtures without chromatographic separation. The quantification is carried out with the help of kinetic laws, which require knowledge of the conditions in the reaction chamber, the reduced ion moblilities and the reaction rate constant kPT under these conditions. Ion-dipole collision theory can be used to calculate kPT. One approach is an extension of Langevin's equation and is known as average dipole orientation (ADO). In a further development, the analytical solution of ADO was replaced by trajectory analysis, which resulted in capture theory. The calculations according to ADO and capture theory require precise knowledge of the dipole moment and the polarizability of the respective target molecule. However, for many relevant indoor related substances, these data are insufficiently known or not known at all. Consequently, the dipole moment μD and polarizability α of 114 organic compounds that are frequently found in indoor air had to be determined using advanced quantum mechanical methods. This required the development of an automated workflow that performs conformer analysis before computing μD and α using density functional theory (DFT). Then the reaction rate constants with the H3O+ ion are calculated according to the ADO theory (kADO), capture theory (kcap) and advanced capture theory for different conditions in the reaction chamber. The kinetic parameters are evaluated with regard to their plausibility and critically discussed for their applicability in PTR-MS measurements.
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Affiliation(s)
- Tunga Salthammer
- Fraunhofer WKI, Department of Material Analysis and Indoor Chemistry 38108 Braunschweig Germany
| | - Uwe Hohm
- Institute of Physical and Theoretical Chemistry, University of Braunschweig - Institute of Technology 38106 Braunschweig Germany
| | - Marcel Stahn
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn 53115 Bonn Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn 53115 Bonn Germany
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9
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Frank ES, Fan H, Grassian VH, Tobias DJ. Adsorption of 6-MHO on two indoor relevant surface materials: SiO 2 and TiO 2. Phys Chem Chem Phys 2023; 25:3930-3941. [PMID: 36648281 DOI: 10.1039/d2cp04876k] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The compound 6-methyl-5-hepten-2-one (6-MHO) is a product of skin oil ozonolysis and is of significance in understanding the role of human occupants in the indoor environment. We present a joint computational and experimental study investigating the adsorption of 6-MHO on two model indoor relevant surfaces, SiO2, a model for a glass window, and TiO2, a component of paint and self-cleaning surfaces. Our classical force field-based molecular dynamics, ab initio molecular dynamics simulations, and FTIR absorption spectra indicate 6-MHO can adsorb on to both of these surfaces via hydrogen and π-hydrogen bonds and is quite stable due to the linear geometry of 6-MHO. Detailed analysis of 6-MHO on the SiO2 surface shows that relative humidity does not impact surface adsorption and adsorbed water does not displace 6-MHO from the hydroxylated SiO2 surface. Additionally, the desorption kinetics of 6-MHO from the hydroxylated SiO2 surface is compared to other compounds found in indoor environments and 6-MHO is shown to desorb with a first order rate constant that is approximately four times slower than that of limonene, but six times faster than that of carvone. In addition, our joint results indicate 6-MHO forms a stronger interaction with the TiO2 surface compared to the SiO2 surface. This study suggests that skin oil ozonolysis products can partition to indoor surfaces leading to the formation of organic films.
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Affiliation(s)
- Elianna S Frank
- Department of Chemistry, University of California, Irvine, California, 92697, USA.
| | - Hanyu Fan
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, 92093, USA.
| | - Vicki H Grassian
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, 92093, USA.
| | - Douglas J Tobias
- Department of Chemistry, University of California, Irvine, California, 92697, USA.
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10
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Molot J, Sears M, Marshall LM, Bray RI. Neurological susceptibility to environmental exposures: pathophysiological mechanisms in neurodegeneration and multiple chemical sensitivity. REVIEWS ON ENVIRONMENTAL HEALTH 2022; 37:509-530. [PMID: 34529912 DOI: 10.1515/reveh-2021-0043] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 08/13/2021] [Indexed: 05/23/2023]
Abstract
The World Health Organization lists air pollution as one of the top five risks for developing chronic non-communicable disease, joining tobacco use, harmful use of alcohol, unhealthy diets and physical inactivity. This review focuses on how host defense mechanisms against adverse airborne exposures relate to the probable interacting and overlapping pathophysiological features of neurodegeneration and multiple chemical sensitivity. Significant long-term airborne exposures can contribute to oxidative stress, systemic inflammation, transient receptor subfamily vanilloid 1 (TRPV1) and subfamily ankyrin 1 (TRPA1) upregulation and sensitization, with impacts on olfactory and trigeminal nerve function, and eventual loss of brain mass. The potential for neurologic dysfunction, including decreased cognition, chronic pain and central sensitization related to airborne contaminants, can be magnified by genetic polymorphisms that result in less effective detoxification. Onset of neurodegenerative disorders is subtle, with early loss of brain mass and loss of sense of smell. Onset of MCS may be gradual following long-term low dose airborne exposures, or acute following a recognizable exposure. Upregulation of chemosensitive TRPV1 and TRPA1 polymodal receptors has been observed in patients with neurodegeneration, and chemically sensitive individuals with asthma, migraine and MCS. In people with chemical sensitivity, these receptors are also sensitized, which is defined as a reduction in the threshold and an increase in the magnitude of a response to noxious stimulation. There is likely damage to the olfactory system in neurodegeneration and trigeminal nerve hypersensitivity in MCS, with different effects on olfactory processing. The associations of low vitamin D levels and protein kinase activity seen in neurodegeneration have not been studied in MCS. Table 2 presents a summary of neurodegeneration and MCS, comparing 16 distinctive genetic, pathophysiological and clinical features associated with air pollution exposures. There is significant overlap, suggesting potential comorbidity. Canadian Health Measures Survey data indicates an overlap between neurodegeneration and MCS (p < 0.05) that suggests comorbidity, but the extent of increased susceptibility to the other condition is not established. Nevertheless, the pathways to the development of these conditions likely involve TRPV1 and TRPA1 receptors, and so it is hypothesized that manifestation of neurodegeneration and/or MCS and possibly why there is divergence may be influenced by polymorphisms of these receptors, among other factors.
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Affiliation(s)
- John Molot
- Family Medicine, University of Ottawa Faculty of Medicine, North York, ON, Canada
| | | | | | - Riina I Bray
- Family and Community Medicine, University of Toronto, Toronto, ON, Canada
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11
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Wu S, Kim E, Vethanayagam D, Zhao R. Indoor partitioning and potential thirdhand exposure to carbonyl flavoring agents added in e-cigarettes and hookah tobacco. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:2294-2309. [PMID: 36408779 DOI: 10.1039/d2em00365a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Flavoring agents added to the e-cigarettes and hookah tobacco have increased the attractiveness of novel nicotine products. Many widely used flavorings are carbonyls, which are toxic to humans. In an indoor environment, residents can be exposed to such harmful flavorings previously emitted to the surrounding environment, through a process termed thirdhand exposure. The recent discovery of a large volume of indoor reservoirs emphasizes the importance of indoor partitioning, which is responsible for thirdhand exposure. Indoor partitioning can be expressed with partitioning coefficients, such as Henry's law solubility constant (H). However, reliable H values for many key flavorings are currently lacking. To better understand their environmental behavior, this study experimentally determined the effective Henry's law constant (Hcps,eff) using the inert gas stripping (IGS) method. Further, the influence of the hydration process for target flavorings was quantified using proton nuclear magnetic resonance (1H NMR) spectroscopy. We found that hydration of α-dicarbonyls (diacetyl and 2,3-pentanedione) enhanced their Hcps,eff from their intrinsic Henry's law constant (Hcps) by a factor of 3.52 and 2.88, respectively. The two-dimensional partitioning plots were employed to simulate the indoor phase distribution and evaluate the pathways of human exposure. Our findings show that the indoor partitioning of many harmful flavorings is highly sensitive to temperature and the size of indoor reservoirs, indicating that residents are likely to experience third-hand exposure.
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Affiliation(s)
- Shuang Wu
- Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada.
| | - Erica Kim
- Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada.
| | - Dilini Vethanayagam
- Department of Medicine, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada
| | - Ran Zhao
- Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada.
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12
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Li Y, He L, Xie D, Zhao A, Wang L, Kreisberg NM, Jayne J, Liu Y. Strong temperature influence and indiscernible ventilation effect on dynamics of some semivolatile organic compounds in the indoor air of an office. ENVIRONMENT INTERNATIONAL 2022; 165:107305. [PMID: 35635961 DOI: 10.1016/j.envint.2022.107305] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 04/26/2022] [Accepted: 05/14/2022] [Indexed: 06/15/2023]
Abstract
Many manmade organic air pollutants are semivolatile and primarily used and exposed indoors. It remains unclear how indoor environmental parameters affect indoor air dynamics of semivolatile organic compounds (SVOCs) in real-world indoor conditions, which directly relates to human exposure. By making time-resolved SVOC measurements over multiple weeks in an office, we characterized the indoor air dynamics of six representative SVOCs which were mainly present in the gas phase and of indoor origins, and investigated the effects of the temperature and ventilation rate. The six species include di-isobutyl phthalate and di-n-butyl phthalate, as well as two n-alkanes and two siloxanes. Airborne concentrations of all six SVOCs responded strongly and quickly to changes in the indoor temperature. The temperature dependence of individual species can be well fitted in the form of the van't Hoff equation, and explained 65-86% of the observed variation in the logarithm-transformed concentrations. In contrast, increasing the ventilation rate by a factor of 3-5 for hours at a constant temperature had no discernible influence on the SVOC concentrations. Further kinetic modeling analysis suggests that the observed fast temperature response and indiscernible ventilation effect are both associated with SVOC sorption onto indoor surfaces, which dramatically slows the response of SVOC concentration to changes in the ventilation rate and speeds up the response to changes in the temperature. These results highlight the importance of sorption reservoirs on regulating indoor SVOC dynamics and also have important implications for controlling and assessing indoor air exposure to SVOCs.
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Affiliation(s)
- Yatai Li
- Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Science and Engineering, Peking University, Beijing 100871, China
| | - Longkun He
- Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Science and Engineering, Peking University, Beijing 100871, China
| | - Di Xie
- Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Science and Engineering, Peking University, Beijing 100871, China
| | - Anqi Zhao
- Beijing Key Laboratory of Heating, Gas Supply, Ventilation and Air Conditioning, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Lixin Wang
- Beijing Key Laboratory of Heating, Gas Supply, Ventilation and Air Conditioning, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | | | - John Jayne
- Aerodyne Research Inc., Billerica, MA 01821, United States
| | - Yingjun Liu
- Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Science and Engineering, Peking University, Beijing 100871, China.
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13
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Wu S, Hayati SK, Kim E, de la Mata AP, Harynuk JJ, Wang C, Zhao R. Henry's Law Constants and Indoor Partitioning of Microbial Volatile Organic Compounds. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:7143-7152. [PMID: 35522906 DOI: 10.1021/acs.est.1c07882] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Microbial volatile organic compounds (MVOCs) play an essential role in many environmental fields, such as indoor air quality. Long-term exposure to odorous and toxic MVOCs can negatively affect the health of occupants. Recently, the involvement of surface reservoirs in indoor chemistry has been realized, which signifies the importance of the phase partitioning of volatile organic pollutants. However, reliable partition coefficients of many MVOCs are currently lacking. Equilibrium partition coefficients, such as Henry's law constant, H, are crucial for understanding the environmental behavior of chemicals. This study aims to experimentally determine the H values and their temperature dependence for key MVOCs under temperature relevant to the indoor environment. The H values were determined with the inert gas-stripping (IGS) method and variable phase ratio headspace (VPR-HS) technique. A two-dimensional partitioning model was applied to predict the indoor phase distribution of MVOCs and potential exposure pathways to the residences. The findings show that the MVOCs are likely distributed between the gas and weakly polar (e.g., organic-rich) reservoirs indoors. Temperature and the volume of reservoirs can sensitively affect indoor partitioning. Our results give a more comprehensive view of indoor chemical partitioning and exposure.
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Affiliation(s)
- Shuang Wu
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Siti K Hayati
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Erica Kim
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - A Paulina de la Mata
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - James J Harynuk
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Chen Wang
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Ran Zhao
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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14
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Salthammer T, Morrison GC. Temperature and indoor environments. INDOOR AIR 2022; 32:e13022. [PMID: 35622714 DOI: 10.1111/ina.13022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/20/2022] [Accepted: 03/13/2022] [Indexed: 06/15/2023]
Abstract
From the thermodynamic perspective, the term temperature is clearly defined for ideal physical systems: A unique temperature can be assigned to each black body via its radiation spectrum, and the temperature of an ideal gas is given by the velocity distribution of the molecules. While the indoor environment is not an ideal system, fundamental physical and chemical processes, such as diffusion, partitioning equilibria, and chemical reactions, are predictably temperature-dependent. For example, the logarithm of reaction rate and equilibria constants are proportional to the reciprocal of the absolute temperature. It is therefore possible to have non-linear, very steep changes in chemical phenomena over a relatively small temperature range. On the contrary, transport processes are more influenced by spatial temperature, momentum, and pressure gradients as well as by the density, porosity, and composition of indoor materials. Consequently, emergent phenomena, such as emission rates or dynamic air concentrations, can be the result of complex temperature-dependent relationships that require a more empirical approach. Indoor environmental conditions are further influenced by the thermal comfort needs of occupants. Not only do occupants have to create thermal conditions that serve to maintain their core body temperature, which is usually accomplished by wearing appropriate clothing, but also the surroundings must be adapted so that they feel comfortable. This includes the interaction of the living space with the ambient environment, which can vary greatly by region and season. Design of houses, apartments, commercial buildings, and schools is generally utility and comfort driven, requiring an appropriate energy balance, sometimes considering ventilation but rarely including the impact of temperature on indoor contaminant levels. In our article, we start with a review of fundamental thermodynamic variables and discuss their influence on typical indoor processes. Then, we describe the heat balance of people in their thermal environment. An extensive literature study is devoted to the thermal conditions in buildings, the temperature-dependent release of indoor pollutants from materials and their distribution in the various interior compartments as well as aspects of indoor chemistry. Finally, we assess the need to consider temperature holistically with regard to the changes to be expected as a result of global emergencies such as climate change.
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Affiliation(s)
- Tunga Salthammer
- Department of Material Analysis and Indoor Chemistry, Fraunhofer WKI, Braunschweig, Germany
| | - Glenn C Morrison
- Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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15
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Abbatt JPD, Morrison GC, Grassian VH, Shiraiwa M, Weschler CJ, Ziemann PJ. How should we define an indoor surface? INDOOR AIR 2022; 32:e12955. [PMID: 35104002 DOI: 10.1111/ina.12955] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 10/23/2021] [Accepted: 10/27/2021] [Indexed: 06/14/2023]
Affiliation(s)
| | - Glenn C Morrison
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Vicki H Grassian
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, USA
| | - Manabu Shiraiwa
- Department of Chemistry, University of California, Irvine, California, USA
| | - Charles J Weschler
- Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, New Jersey, USA
| | - Paul J Ziemann
- Department of Chemistry, University of Colorado, Boulder, Colorado, USA
- Cooperative Institute for Research in Environmental Sciences (CIRES), Boulder, Colorado, USA
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16
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Wu T, Tasoglou A, Huber H, Stevens PS, Boor BE. Influence of Mechanical Ventilation Systems and Human Occupancy on Time-Resolved Source Rates of Volatile Skin Oil Ozonolysis Products in a LEED-Certified Office Building. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:16477-16488. [PMID: 34851619 DOI: 10.1021/acs.est.1c03112] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Building mechanical ventilation systems are a major driver of indoor air chemistry as their design and operation influences indoor ozone (O3) concentrations, the dilution and transport of indoor-generated volatile organic compounds (VOCs), and indoor environmental conditions. Real-time VOC and O3 measurements were integrated with a building sensing platform to evaluate the influence of mechanical ventilation modes and human occupancy on the dynamics of skin oil ozonolysis products (SOOPs) in an office in a LEED-certified building during the winter. The ventilation system operated under variable recirculation ratios (RRs) from RR = 0 (100% outdoor air) to RR = 1 (100% recirculation air). Time-resolved source rates for 6-methyl-5-hepten-2-one (6-MHO), 4-oxopentanal (4-OPA), and decanal were highly dynamic and changed throughout the day with RR and occupancy. Total SOOP source rates during high-occupancy periods (10:00-18:00) varied from 2500-3000 μg h-1 when RR = 0.1 to 6300-6700 μg h-1 when RR = 1. Source rates for gas-phase reactions, outdoor air, and occupant-associated emissions generally decreased with increasing RR. The recirculation air source rate increased with RR and typically became the dominant source for RR > 0.5. SOOP emissions from surface reservoirs were also a prominent source, contributing 10-50% to total source rates. Elevated per person SOOP emission factors were observed, potentially due to multiple layers of soiled clothing worn during winter.
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Affiliation(s)
- Tianren Wu
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Ray W. Herrick Laboratories, Center for High Performance Buildings, Purdue University, West Lafayette, Indiana 47907, United States
| | - Antonios Tasoglou
- RJ Lee Group Incorporated, Monroeville, Pennsylvania 15146, United States
| | - Heinz Huber
- Edelweiss Technology Solutions, Limited Liability Company, Novelty, Ohio 44072, United States
| | - Philip S Stevens
- O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 47405, United States
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Brandon E Boor
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Ray W. Herrick Laboratories, Center for High Performance Buildings, Purdue University, West Lafayette, Indiana 47907, United States
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17
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Lakey PSJ, Eichler CMA, Wang C, Little JC, Shiraiwa M. Kinetic multi-layer model of film formation, growth, and chemistry (KM-FILM): Boundary layer processes, multi-layer adsorption, bulk diffusion, and heterogeneous reactions. INDOOR AIR 2021; 31:2070-2083. [PMID: 33991124 DOI: 10.1111/ina.12854] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/15/2021] [Accepted: 04/21/2021] [Indexed: 06/12/2023]
Abstract
Large surface area-to-volume ratios indoors cause heterogeneous interactions to be especially important. Semi-volatile organic compounds can deposit on impermeable indoor surfaces forming thin organic films. We developed a new model to simulate the initial film formation by treating gas-phase diffusion and turbulence through a surface boundary layer and multi-layer reversible adsorption on rough surfaces, as well as subsequent film growth by resolving bulk diffusion and chemical reactions in a film. The model was applied with consistent parameters to reproduce twenty-one sets of film formation measurements due to multi-layer adsorption of multiple phthalates onto different indoor-relevant surfaces, showing that the films should initially be patchy with the formation of pyramid-like structures on the surface. Sensitivity tests showed that highly turbulent conditions can lead to the film growing by more than a factor of two compared to low turbulence conditions. If surface films adopt an ultra-viscous state with bulk diffusion coefficients of less than 10-18 cm2 s-1 , a significant decrease in film growth is expected. The presence of chemical reactions in the film has the potential to increase the rate of film growth by nearly a factor of two.
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Affiliation(s)
| | - Clara M A Eichler
- Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA, USA
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Chunyi Wang
- Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA, USA
| | - John C Little
- Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA, USA
| | - Manabu Shiraiwa
- Department of Chemistry, University of California, Irvine, CA, USA
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18
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Sheu R, Fortenberry CF, Walker MJ, Eftekhari A, Stönner C, Bakker A, Peccia J, Williams J, Morrison GC, Williams BJ, Gentner DR. Evaluating Indoor Air Chemical Diversity, Indoor-to-Outdoor Emissions, and Surface Reservoirs Using High-Resolution Mass Spectrometry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:10255-10267. [PMID: 34270218 PMCID: PMC8461992 DOI: 10.1021/acs.est.1c01337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Detailed offline speciation of gas- and particle-phase organic compounds was conducted using gas/liquid chromatography with traditional and high-resolution mass spectrometers in a hybrid targeted/nontargeted analysis. Observations were focused on an unoccupied home and were compared to two other indoor sites. Observed gas-phase organic compounds span the volatile to semivolatile range, while functionalized organic aerosols extend from intermediate volatility to ultra-low volatility, including a mix of oxygen, nitrogen, and sulfur-containing species. Total gas-phase abundances of hydrocarbon and oxygenated gas-phase complex mixtures were elevated indoors and strongly correlated in the unoccupied home. While gas-phase concentrations of individual compounds generally decreased slightly with greater ventilation, their elevated ratios relative to controlled emissions of tracer species suggest that the dilution of gas-phase concentrations increases off-gassing from surfaces and other indoor reservoirs, with volatility-dependent responses to dynamically changing environmental factors. Indoor-outdoor emissions of gas-phase intermediate-volatility/semivolatile organic hydrocarbons from the unoccupied home averaged 6-11 mg h-1, doubling with ventilation. While the largest single-compound emissions observed were furfural (61-275 mg h-1) and acetic acid, observations spanned a wide range of individual volatile chemical products (e.g., terpenoids, glycol ethers, phthalates, other oxygenates), highlighting the abundance of long-lived reservoirs resulting from prior indoor use or materials, and their gradual transport outdoors.
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Affiliation(s)
- Roger Sheu
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
| | - Claire F Fortenberry
- Department of Energy, Environmental, & Chemical Engineering and Center for Aerosol Science and Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Michael J Walker
- Department of Energy, Environmental, & Chemical Engineering and Center for Aerosol Science and Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Azin Eftekhari
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27515, United States
| | - Christof Stönner
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz 55128, Germany
| | - Alexa Bakker
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
| | - Jordan Peccia
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
| | - Jonathan Williams
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz 55128, Germany
| | - Glenn C Morrison
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27515, United States
| | - Brent J Williams
- Department of Energy, Environmental, & Chemical Engineering and Center for Aerosol Science and Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Drew R Gentner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
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19
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Jones SH, Hosse FPR, Yang X, Donaldson DJ. Loss of NO(g) to painted surfaces and its re-emission with indoor illumination. INDOOR AIR 2021; 31:566-573. [PMID: 32920844 PMCID: PMC7983918 DOI: 10.1111/ina.12741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 08/07/2020] [Accepted: 09/01/2020] [Indexed: 05/10/2023]
Abstract
Heterogeneous surface reactions play a key role in the chemistry of the indoor environment because of the large indoor surface-to-volume ratio. The presence of photocatalytic material in indoor paints may allow photochemical reactions to occur at wavelengths of light that are present indoors. One such potential reaction is the heterogeneous photooxidation of NO to HONO. NO(g) is commonly found indoors, originating from combustion sources, ventilation and infiltration of outdoor air. We studied the interaction of NO(g) with painted surfaces illuminated with indoor fluorescent and incandescent lighting. There is a loss of NO(g) to painted surfaces in the dark at both 0 and 50% RH. At 50% RH, there is a re-release of some of that NO(g) under illumination. The same behavior is observed for illumination of different colored paints. This is in contrast to what is seen with TiO2 as the substrate, where photoenhanced uptake of NO(g) and formation of NO2 (g) are observed. We hypothesize that the loss of NO(g) is due to adsorption and diffusion into the paint. The re-release of NO under illumination is thought to be due to photooxidation of NO to HONO on the painted surface at higher relative humidities and subsequent HONO photolysis.
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Affiliation(s)
| | | | - Xiaoying Yang
- Department of ChemistryUniversity of TorontoTorontoONCanada
| | - D. James Donaldson
- Department of ChemistryUniversity of TorontoTorontoONCanada
- Department of Physical and Environmental SciencesUniversity of Toronto ScarboroughTorontoONCanada
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20
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Zhou S, Liu Z, Wang Z, Young CJ, VandenBoer TC, Guo BB, Zhang J, Carslaw N, Kahan TF. Hydrogen Peroxide Emission and Fate Indoors during Non-bleach Cleaning: A Chamber and Modeling Study. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15643-15651. [PMID: 33258369 DOI: 10.1021/acs.est.0c04702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Activities such as household cleaning can greatly alter the composition of air in indoor environments. We continuously monitored hydrogen peroxide (H2O2) from household non-bleach surface cleaning in a chamber designed to simulate a residential room. Mixing ratios of up to 610 ppbv gaseous H2O2 were observed following cleaning, orders of magnitude higher than background levels (sub-ppbv). Gaseous H2O2 levels decreased rapidly and irreversibly, with removal rate constants (kH2O2) 17-73 times larger than air change rate (ACR). Increasing the surface-area-to-volume ratio within the room caused peak H2O2 mixing ratios to decrease and kH2O2 to increase, suggesting that surface uptake dominated H2O2 loss. Volatile organic compound (VOC) levels increased rapidly after cleaning and then decreased with removal rate constants 1.2-7.2 times larger than ACR, indicating loss due to surface partitioning and/or chemical reactions. We predicted photochemical radical production rates and steady-state concentrations in the simulated room using a detailed chemical model for indoor air (the INDCM). Model results suggest that, following cleaning, H2O2 photolysis increased OH concentrations by 10-40% to 9.7 × 105 molec cm-3 and hydroperoxy radical (HO2) concentrations by 50-70% to 2.3 × 107 molec cm-3 depending on the cleaning method and lighting conditions.
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Affiliation(s)
- Shan Zhou
- Department of Chemistry, Syracuse University, Syracuse, New York 13244, United States
| | - Zhenlei Liu
- Department of Mechanical and Aerospace Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Zixu Wang
- Department of Environment and Geography, University of York, York YO10 5DD, U.K
| | - Cora J Young
- Department of Chemistry, York University, Toronto, Ontario M3J 1P3, Canada
| | | | - B Beverly Guo
- Department of Mechanical and Aerospace Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Jianshun Zhang
- Department of Mechanical and Aerospace Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Nicola Carslaw
- Department of Environment and Geography, University of York, York YO10 5DD, U.K
| | - Tara F Kahan
- Department of Chemistry, Syracuse University, Syracuse, New York 13244, United States
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9, Canada
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21
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Lim CY, Abbatt JP. Chemical Composition, Spatial Homogeneity, and Growth of Indoor Surface Films. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:14372-14379. [PMID: 33156609 DOI: 10.1021/acs.est.0c04163] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Organic films on indoor surfaces are ubiquitous, but details about their composition and growth over timescales less than a month are not fully understood. To address these gaps in understanding, organic film samples in an apartment unit were collected over the course of 17 days using passive samplers and analyzed in a non-targeted manner using direct analysis in real-time mass spectrometry (DART-MS). Overall, the chemical composition observed across various locations within the apartment are very similar. Mass spectra also show clear evidence for the growth of semi-volatile compounds from natural sources and consumer products, such as carboxylic acids and plasticizers. Certain compounds show evidence for equilibration, mostly consistent with surface partitioning models based on octanol-air partition coefficients (Koa). Compounds which have higher molecular weight or larger Koa values tend to equilibrate later, leading to an overall shift in the composition of the film as a function of collection time. Growth rates of film thickness are at least 0.05 nm/day based on a limited number of individually calibrated ions.
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Affiliation(s)
- Christopher Y Lim
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Jonathan P Abbatt
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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