1
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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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Yao Z, Morrison G. Reactive oxygen species on indoor surfaces. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024. [PMID: 38805261 DOI: 10.1039/d4em00031e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Reactive oxygen species (ROS) are relatively unstable oxygen-containing radicals or non-radicals, some of which may react with tissues and biomolecules after entering the body. ROS is present in indoor aerosols, but it is unclear how much of that ROS is of indoor origin. Indoor surface films have been hypothesized to be a major source of the ROS observed on indoor aerosols. In this study, the ROS concentration on residential indoor surfaces was measured using a xylenol orange ferrous oxidation assay after wiping and extraction. On genuine surfaces frequently touched by apartment occupants, the concentration was >0.2 nmol cm-2; infrequently touched surfaces were at or below detection limits. On clean glass plates that had been deployed in apartments for 6 weeks, horizontal plates had higher concentrations than vertically oriented plates. The highest concentration, 1.3 nmol cm-2, was observed on a horizontally oriented plate close to an electric stove. To simulate the dynamic oxidation of unsaturated hydrocarbons on indoor surfaces, a surface lipid mixture (SLM) was dosed on 19 glass plates which were then exposed to untreated laboratory air for periods ranging from 1 to 56 days. During the first 5-6 days, the ROS concentration increased roughly linearly to a maximum of 5-6 nmol cm-2. Then the concentration ceased to increase, perhaps because reactive sites had become depleted. After 2 weeks, ROS decreased slowly, possibly due to a combination of volatilization, decomposition and continued formation by autoxidation. These field and laboratory results support the hypothesis that indoor surfaces can be a source of ROS.
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Affiliation(s)
- Zhenduo Yao
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Glenn Morrison
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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3
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Deng H, Qiu J, Zhang R, Xu J, Qu Y, Wang J, Liu Y, Gligorovski S. Ozone Chemistry on Greasy Glass Surfaces Affects the Levels of Volatile Organic Compounds in Indoor Environments. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:8393-8403. [PMID: 38691770 DOI: 10.1021/acs.est.3c08196] [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: 05/03/2024]
Abstract
The chemistry of ozone (O3) on indoor surfaces leads to secondary pollution, aggravating the air quality in indoor environments. Here, we assess the heterogeneous chemistry of gaseous O3 with glass plates after being 1 month in two different kitchens where Chinese and Western styles of cooking were applied, respectively. The uptake coefficients of O3 on the authentic glass plates were measured in the dark and under UV light irradiation typical for indoor environments (320 nm < λ < 400 nm) at different relative humidities. The gas-phase product compounds formed upon reactions of O3 with the glass plates were evaluated in real time by a proton-transfer-reaction quadrupole-interface time-of-flight mass spectrometer. We observed typical aldehydes formed by the O3 reactions with the unsaturated fatty acid constituents of cooking oils. The formation of decanal, 6-methyl-5-hepten-2-one (6-MHO), and 4-oxopentanal (4-OPA) was also observed. The employed dynamic mass balance model shows that the estimated mixing ratios of hexanal, octanal, nonanal, decanal, undecanal, 6-MHO, and 4-OPA due to O3 chemistry with authentic grime-coated kitchen glass surfaces are higher in the kitchen where Chinese food was cooked compared to that where Western food was cooked. These results show that O3 chemistry on greasy glass surfaces leads to enhanced VOC levels in indoor environments.
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Affiliation(s)
- Huifan Deng
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou 510640, China
- Chinese Academy of Science, Center for Excellence in Deep Earth Science, Guangzhou 510640, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jia Qiu
- Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering and Center for Environment and Health, Peking University, Beijing 100871, China
| | - Runqi Zhang
- Department of Materials Environmental Engineering, Shanxi Polytechnic College, Shanxi 237016, China
| | - Jinli Xu
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou 510640, China
- Chinese Academy of Science, Center for Excellence in Deep Earth Science, Guangzhou 510640, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuekun Qu
- Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering and Center for Environment and Health, Peking University, Beijing 100871, China
| | - Jixuan Wang
- Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering and Center for Environment and Health, Peking University, Beijing 100871, China
| | - Yingjun Liu
- Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering and Center for Environment and Health, Peking University, Beijing 100871, China
| | - Sasho Gligorovski
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou 510640, China
- Chinese Academy of Science, Center for Excellence in Deep Earth Science, Guangzhou 510640, China
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4
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Langer S, Weschler CJ, Bekö G, Morrison G, Sjöblom A, Giovanoulis G, Wargocki P, Wang N, Zannoni N, Yang S, Williams J. Squalene Depletion in Skin Following Human Exposure to Ozone under Controlled Chamber Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6693-6703. [PMID: 38577981 DOI: 10.1021/acs.est.3c09394] [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: 04/06/2024]
Abstract
A major component of human skin oil is squalene, a highly unsaturated hydrocarbon that protects the skin from atmospheric oxidants. Skin oil, and thus squalene, is continuously replenished on the skin surface. Squalene is also quickly consumed through reactions with ozone and other oxidants. This study examined the extent of squalene depletion in the skin oils of the forearm of human volunteers after exposure to ozone in a climate chamber. Temperature, relative humidity (RH), skin coverage by clothing, and participants' age were varied in a controlled manner. Concentrations of squalene were determined in skin wipe samples collected before and after ozone exposure. Exposures to ozone resulted in statistically significant decreases in post-exposure squalene concentrations compared to pre-exposure squalene concentrations in the skin wipes when squalene concentrations were normalized by concentrations of co-occurring cholesterol but not by co-occurring pyroglutamic acid (PGA). The rate of squalene loss due to ozonolysis was lower than its replenishment on the skin surface. Within the ranges examined, temperature and RH did not significantly affect the difference between normalized squalene levels in post-samples versus pre-samples. Although not statistically significant, skin coverage and age of the volunteers (three young adults, three seniors, and three teenagers) did appear to impact squalene depletion on the skin surfaces.
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Affiliation(s)
- Sarka Langer
- IVL Swedish Environmental Research Institute, Environmental Chemistry, 40014 Göteborg, Sweden
- Chalmers University of Technology, Department of Architecture and Civil Engineering, Division Building Services Engineering, 412 96 Göteborg, Sweden
| | - Charles J Weschler
- Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, New Jersey 08854, United States
- International Centre for Indoor Environment and Energy, Department of Environmental and Resource Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Gabriel Bekö
- International Centre for Indoor Environment and Energy, Department of Environmental and Resource Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
- Healthy and Sustainable Built Environment Research Centre, Ajman University, P.O. Box 346 Ajman, United Arab Emirates
| | - Glenn Morrison
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7431, United States
| | - Ann Sjöblom
- IVL Swedish Environmental Research Institute, Environmental Chemistry, 40014 Göteborg, Sweden
| | - Georgios Giovanoulis
- IVL Swedish Environmental Research Institute, Environmental Chemistry, 40014 Göteborg, Sweden
| | - Pawel Wargocki
- International Centre for Indoor Environment and Energy, Department of Environmental and Resource Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Nijing Wang
- Atmospheric Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - Nora Zannoni
- Atmospheric Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - Shen Yang
- Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Jonathan Williams
- Atmospheric Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
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5
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Fahy WD, Wania F, Abbatt JPD. When Does Multiphase Chemistry Influence Indoor Chemical Fate? ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:4257-4267. [PMID: 38380897 DOI: 10.1021/acs.est.3c08751] [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: 02/22/2024]
Abstract
Human chemical exposure often occurs indoors, where large variability in contaminant concentrations and indoor chemical dynamics make assessments of these exposures challenging. A major source of uncertainty lies in the rates of chemical transformations which, due to high surface-to-volume ratios and rapid air change rates relative to rates of gas-phase reactions indoors, are largely gas-surface multiphase processes. It remains unclear how important such chemistry is in controlling indoor chemical lifetimes and, therefore, human exposure to both parent compounds and transformation products. We present a multimedia steady-state fugacity-based model to assess the importance of multiphase chemistry relative to cleaning and mass transfer losses, examine how the physicochemical properties of compounds and features of the indoor environment affect these processes, and investigate uncertainties pertaining to indoor multiphase chemistry and chemical lifetimes. We find that multiphase reactions can play an important role in chemical fate indoors for reactive compounds with low volatility, i.e., octanol-air equilibrium partitioning ratios (Koa) above 108, with the impact of this chemistry dependent on chemical identity, oxidant type and concentration, and other parameters. This work highlights the need for further research into indoor chemical dynamics and multiphase chemistry to constrain human exposure to chemicals in the built environment.
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Affiliation(s)
- William D Fahy
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Frank Wania
- Department of Physical and Environmental Sciences, University of Toronto at Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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6
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Zhou Z, Crilley LR, Ditto JC, VandenBoer TC, Abbatt JPD. Chemical Fate of Oils on Indoor Surfaces: Ozonolysis and Peroxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:15546-15557. [PMID: 37647222 DOI: 10.1021/acs.est.3c04009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Unsaturated triglycerides found in food and skin oils are reactive in ambient air. However, the chemical fate of such compounds has not been well characterized in genuine indoor environments. Here, we monitored the aging of oil coatings on glass surfaces over a range of environmental conditions, using mass spectrometry, nuclear magnetic resonance (NMR), and electron paramagnetic resonance (EPR) techniques. Upon room air exposure (up to 17 ppb ozone), the characteristic ozonolysis products, secondary ozonides, were observed on surfaces near the cooking area of a commercial kitchen, along with condensed-phase aldehydes. In an office setting, ozonolysis is also the dominant degradation pathway for oil films exposed to air. However, for indoor enclosed spaces such as drawers, the depleted air flow makes lipid autoxidation more favorable after an induction period of a few days. Forming hydroperoxides as the major primary products, this radical-mediated peroxidation behavior is accelerated by indoor direct sunlight, but the initiation step in dark settings is still unclear. These results are in accord with radical measurements, indicating that indoor photooxidation facilitates radical formation on surfaces. Overall, many intermediate and end products observed are reactive oxygen species (ROS) that may induce oxidative stress in human bodies. Given that these species can be widely found on both food and household surfaces, their toxicological properties are worth further attention.
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Affiliation(s)
- Zilin Zhou
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Leigh R Crilley
- Department of Chemistry, York University, Toronto, Ontario M3J 1P3, Canada
| | - Jenna C Ditto
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | | | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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7
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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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8
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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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9
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Weschler CJ, Nazaroff WW. Ozone Loss: A Surrogate for the Indoor Concentration of Ozone-Derived Products. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:13569-13578. [PMID: 37639667 DOI: 10.1021/acs.est.3c03968] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Ozone concentrations tend to be substantially lower indoors than outdoors, largely because of ozone reactions with indoor surfaces. When there are no indoor sources of ozone, a common condition, the net concentration of gaseous products derived from indoor ozone chemistry scales linearly with the difference between outdoor and indoor ozone concentrations, termed "ozone loss." As such, ozone loss is a metric that might be used by epidemiologists to disentangle the adverse health effects of ozone's oxidation products from those of exposure to ozone itself. The present paper examines the characteristics, potential utility, and limitations of the ozone loss concept. We show that for commonly occurring indoor conditions, the ozone loss concentration is directly proportional to the total rate constant for ozone removal on surfaces (ksum) and inversely proportional to the net removal of ozone by air exchange (λ) plus surface reactions (ksum). It follows that the ratio of indoor ozone to ozone loss is equal to the ratio of λ to ksum. Ozone loss is a promising metric for probing potential adverse health effects resulting from exposures to products of indoor ozone chemistry. Notwithstanding its virtues, practitioners using it should be mindful of the limitations discussed in this paper.
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Affiliation(s)
- Charles J Weschler
- Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, New Jersey 08854, United States
- International Centre for Indoor Environment and Energy, Technical University of Denmark, Lyngby 2800, Denmark
| | - William W Nazaroff
- Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720-1710, United States
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10
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Morrison GC, Eftekhari A, Lakey PSJ, Shiraiwa M, Cummings BE, Waring MS, Williams B. Partitioning of reactive oxygen species from indoor surfaces to indoor aerosols. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:2310-2323. [PMID: 36314460 DOI: 10.1039/d2em00307d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Reactive oxygen species (ROS) are among the species thought to be responsible for the adverse health effects of particulate matter (PM) inhalation. Field studies suggest that indoor sources of ROS contribute to measured ROS on PM in indoor air. We hypothesize that ozone reacts on indoor surfaces to form semi-volatile ROS, in particular organic peroxides (OPX), which partition to airborne particles. To test this hypothesis, we modeled ozone-induced formation of OPX, its decay and its partitioning to PM in a residential building and compared the results to field measurements. Simulations indicate that, while ROS of outdoor origin is the primary contributor to indoor ROS (in PM), a substantial fraction of ROS present in indoor PM is from ozone-surface chemistry. At an air change rate equal to 1/h, and an outdoor ozone mixing ratio of 35 ppb, 25% of the ROS concentration in air is due to indoor formation and partitioning of OPX to PM. For the same conditions, but with a modest indoor source of PM (1.5 mg h-1), 44% of indoor ROS on PM is of indoor origin. An indoor source of ozone, such as an electrostatic air cleaner, also increases OPX present in indoor PM. The results of the simulations support the hypothesis that ozone-induced formation of OPX on indoor surfaces, and subsequent partitioning to aerosols, is sufficient to explain field observations. Therefore, indoor sourced ROS could contribute meaningfully to total inhaled PM-ROS.
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Affiliation(s)
- Glenn C Morrison
- Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, NC, USA.
| | - Azin Eftekhari
- Department of Chemical and Biomolecular Engineering, Georgia Institute of Technology, GA, USA
| | | | - Manabu Shiraiwa
- Department of Chemistry, University of California Irvine, CA, USA
| | - Bryan E Cummings
- Department of Civil, Architectural and Environmental Engineering, Drexel University, Philadelphia, PA, USA
| | - Michael S Waring
- Department of Civil, Architectural and Environmental Engineering, Drexel University, Philadelphia, PA, USA
| | - Brent Williams
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
- Center for Aerosol Science and Engineering, Washington University in St. Louis, St. Louis, MO, USA
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11
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Coffaro B, Weisel CP. Reactions and Products of Squalene and Ozone: A Review. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:7396-7411. [PMID: 35648815 PMCID: PMC9231367 DOI: 10.1021/acs.est.1c07611] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
This critical review describes the squalene-ozone (SqOz) reaction, or squalene ozonolysis. Ambient ozone penetrates indoors and drives indoor air chemistry. Squalene, a component of human skin oil, contains six carbon-carbon double bonds and is very reactive with ozone. Bioeffluents from people contribute to indoor air chemistry and affect the indoor air quality, resulting in exposures because people spend the majority of their time indoors. The SqOz reaction proceeds through various formation pathways and produces compounds that include aldehydes, ketones, carboxylic acids, and dicarbonyl species, which have a range of volatilities. In this critical review of SqOz chemistry, information on the mechanism of reaction, reaction probability, rate constants, and reaction kinetics are compiled. Characterizations of SqOz reaction products have been done in laboratory experiments and real-world settings. The effect of multiple environmental parameters (ozone concentration, air exchange rate (AER), temperature, and relative humidity (RH)) in indoor settings are summarized. This critical review concludes by identifying the paucity of available exposure, health, and toxicological data for known reaction products. Key knowledge gaps about SqOz reactions leading to indoor exposures and adverse health outcomes are provided as well as an outlook on where the field is headed.
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Affiliation(s)
- Breann Coffaro
- Environmental
and Health Sciences Institute and Graduate Program in Exposure Science, Rutgers, The State University of New Jersey, Piscataway Township, New
Jersey 08854, United
States
| | - Clifford P. Weisel
- Environmental
and Health Sciences Institute and School of Public Health, Rutgers, The State University of New Jersey, Piscataway Township, New
Jersey 08854, United
States
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12
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Gautam T, Wu S, Ma J, Zhao R. Potential Matrix Effects in Iodometry Determination of Peroxides Induced by Olefins. J Phys Chem A 2022; 126:2632-2644. [PMID: 35442038 DOI: 10.1021/acs.jpca.1c10717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Peroxides (H2O2, ROOR, and ROOH) are an important reaction intermediate involved in a number of natural processes, including atmospheric autoxidation and lipid peroxidation in oils and animal tissues. Iodometry is an established spectroscopic technique that has been widely used to quantify total peroxide concentration in food, indoor, and outdoor samples. Iodometry provides selectivity toward peroxides through a quantitative reaction between I- and peroxides to form I3- via a molecular iodine (I2) intermediate. However, equilibrium changes caused by a potential interaction between olefinic species and I2 can suppress I3- formation, thereby underestimating peroxide concentration. For the first time in the current study, this unrecognized interference posed by olefins (OEs) is systematically investigated to gauge its effects on the accuracy of iodometry. A number of model molecules were investigated. The interference was observed to be unique to OEs, but universally affecting different peroxide species such as H2O2, tert-butyl hydroperoxide, and aerosol-bound peroxides. A simple kinetic box model was built to explain this chemistry. The measured rate constant for 3-octenoic acid was found to be 0.84 ± 0.02 M-1 s-1. Overall, our results show matrix effects induced by OEs can underestimate peroxide concentration determined by iodometry for edible oils, indoor environments, and animal fat, but absent in most of the atmospheric samples. Nonetheless, our results point out the importance of this interfering chemistry in matrices enriched with OEs.
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Affiliation(s)
- Tania Gautam
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Alberta, Canada
| | - Shuang Wu
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Alberta, Canada
| | - Jeff Ma
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Alberta, Canada
| | - Ran Zhao
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Alberta, Canada
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13
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Zhang M, Gao Y, Xiong J. Characterization of the off-body squalene ozonolysis on indoor surfaces. CHEMOSPHERE 2022; 291:132772. [PMID: 34742760 DOI: 10.1016/j.chemosphere.2021.132772] [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] [Received: 08/02/2021] [Revised: 10/09/2021] [Accepted: 11/01/2021] [Indexed: 06/13/2023]
Abstract
Chemical reaction and physical transport characteristics of indoor surfaces play an important role in indoor air quality. This study presents a kinetic model to describe the reaction of ozone with squalene on indoor surfaces in a family house, by incorporating external and internal mass transfer, surface partitioning, and chemical reaction on indoor surfaces. Field experiments were performed in the family house. The first 3-days of data, collected when the house was unoccupied, are used to derive the key parameters in the model, which are then used for predicting the concentrations in other unoccupied days. Comparison of squalene oxidation products during the occupied and unoccupied periods shows that even if the house is unoccupied for several days, the indoor concentrations of 6-methyl-5-hepten-2-one (6-MHO) and 4-oxopentanal (4-OPA) remain substantial, demonstrating that surface reaction of ozone with off-body squalene can significantly impact the composition of indoor air. Model predictions of the three compounds (ozone, 6-MHO, and 4-OPA) agree well with the experimental observations for all test days. Furthermore, we make the first attempt to estimate the duration of typical polyunsaturated aldehydes (TOP, TOT, and TTT), which indicated that these compounds, as well as off-body squalene, can persist on indoor surfaces for a relatively long period in the examined residence.
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Affiliation(s)
- Meixia Zhang
- School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Ying Gao
- School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Jianyin Xiong
- School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081, China; Department of Environmental Science, Policy and Management, University of California, Berkeley, CA, 94720, United States.
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14
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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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15
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Abstract
Outdoor ozone transported indoors initiates oxidative chemistry, forming volatile organic products. The influence of ozone chemistry on indoor air composition has not been directly quantified in normally occupied residences. Here, we explore indoor ozone chemistry in a house in California with two adult inhabitants. We utilize space- and time-resolved measurements of ozone and volatile organic compounds (VOCs) acquired over an 8-wk summer campaign. Despite overall low indoor ozone concentrations (mean value of 4.3 ppb) and a relatively low indoor ozone decay constant (1.3 h-1), we identified multiple VOCs exhibiting clear contributions from ozone-initiated chemistry indoors. These chemicals include 6-methyl-5-hepten-2-one (6-MHO), 4-oxopentanal (4-OPA), nonenal, and C8-C12 saturated aldehydes, which are among the commonly reported products from laboratory studies of ozone interactions with indoor surfaces and with human skin lipids. These VOCs together accounted for ≥12% molecular yield with respect to house-wide consumed ozone, with the highest net product yield for nonanal (≥3.5%), followed by 6-MHO (2.7%) and 4-OPA (2.6%). Although 6-MHO and 4-OPA are prominent ozonolysis products of skin lipids (specifically squalene), ozone reaction with the body envelopes of the two occupants in this house are insufficient to explain the observed yields. Relatedly, we observed that ozone-driven chemistry continued to produce 6-MHO and 4-OPA even after the occupants had been away from the house for 5 d. These observations provide evidence that skin lipids transferred to indoor surfaces made substantial contributions to ozone reactivity in the studied house.
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16
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Goldstein AH, Nazaroff WW, Weschler CJ, Williams J. How Do Indoor Environments Affect Air Pollution Exposure? ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:100-108. [PMID: 33284612 DOI: 10.1021/acs.est.0c05727] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Affiliation(s)
- Allen H Goldstein
- Department of Environmental Science, Policy, and Management University of California, Berkeley, California 94720, United States
- Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - William W Nazaroff
- Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - Charles J Weschler
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Lyngby 2800, Denmark
- Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, New Jersey 08854, United States
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17
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Liu J, Deng H, Lakey PSJ, Jiang H, Mekic M, Wang X, Shiraiwa M, Gligorovski S. Unexpectedly High Indoor HONO Concentrations Associated with Photochemical NO 2 Transformation on Glass Windows. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15680-15688. [PMID: 33232600 DOI: 10.1021/acs.est.0c05624] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Nitrous acid (HONO) is an important gaseous pollutant contributing to indoor air pollution because it causes adverse health effects and is the main source of hydroxyl radicals (OH). Here, we present direct measurements of HONO produced through light-induced heterogeneous reactions of NO2 with grime adsorbed on glass window. The uptake coefficients of NO2 [γ(NO2)] on the glass plates from the kitchen increased markedly from (2.3 ± 0.1) × 10-6 at 0% RH to (4.1 ± 0.5) × 10-6 at 90% RH. We report a significant quantity of daytime HONO produced in the kitchen, compared to the living room and bedroom. Kinetic modeling suggests that phase state and bulk diffusivity play important roles in the NO2 uptake; the best fit to the measured uptake coefficients is obtained with fixed diffusion coefficients. Photon scattering may be occurring at the surface of the films, leading to enhanced photon-excitation rates of polycyclic aromatic hydrocarbons. By taking these effects into account, the results from this study indicate that the HONO yields obtained in this study can explain the missing HONO in the photochemical models describing the indoor air chemistry.
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Affiliation(s)
- Jiangping Liu
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Huifan Deng
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Pascale S J Lakey
- Department of Chemistry, University of California, Irvine, Irvine, California 92697-2025, United States
| | - Haoyu Jiang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Majda Mekic
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Manabu Shiraiwa
- Department of Chemistry, University of California, Irvine, Irvine, California 92697-2025, United States
| | - Sasho Gligorovski
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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18
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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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