Isoprene Epoxydiol-Derived Sulfated and Nonsulfated Oligomers Suppress Particulate Mass Loss During Oxidative Aging of Secondary Organic Aerosol

Details

• Personal Author:
  Armstrong NC ; Ault AP ; Chan MN ; Chen Y ; Christensen C ; Cui T ; Gold, Avram ; Surratt JD ; Turpin BJ ; Zhang Y ; Zhang Z
• Description:
  Acid-driven multiphase chemistry of isoprene epoxydiols (IEPOX) with inorganic sulfate aerosols contributes substantially to secondary organic aerosol (SOA) formation, which constitutes a large mass fraction of atmospheric fine particulate matter (PM2.5). However, the atmospheric chemical sinks of freshly generated IEPOX-SOA particles remain unclear. We examined the role of heterogeneous oxidation of freshly generated IEPOX-SOA particles by gas-phase hydroxyl radical (OH) under dark conditions as one potential atmospheric sink. After 4 h of gas-phase OH exposure (approx. 3 × 108 molecules cm-3), chemical changes in smog chamber-generated IEPOX-SOA particles were assessed by hydrophilic interaction liquid chromatography coupled with electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (HILIC/ESI-HR-QTOFMS). A comparison of the molecular-level compositional changes in IEPOX-SOA particles during aging with or without OH revealed that decomposition of oligomers by heterogeneous OH oxidation acts as a sink for OH and maintains a reservoir of low-volatility compounds, including monomeric sulfate esters and oligomer fragments. We propose tentative structures and formation mechanisms for previously uncharacterized SOA constituents in PM2.5. Our results suggest that this -driven renewal of low-volatility products may extend the atmospheric lifetimes of particle-phase IEPOX-SOA by slowing the production of low-molecular weight, high-volatility organic fragments and likely contributes to the large quantities of 2-methyltetrols and methyltetrol sulfates reported in PM2.5. [Description provided by NIOSH]
• Subjects:
  Aerosols Air Pollutants, Occupational Environmental Exposure Environmental Pollution Occupational Health Particulate Matter Safety Volatile Organic Compounds
• Keywords:
  Air Pollutants Atmospheric Lifetime Atmospheric Multiphase Chemistry Author Keywords: Hydroxyl Radical Environmental Pollution Fragmentation Hydroxyl Groups Methyltetrols Organosulfates Oxidation Particulates Revolatilization VOCs Volatile Organic Compounds Volatiles

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• ISSN:
  0013-936X
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Michigan ; North Carolina ; OSHA Region 4 ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  56
• Issue:
  23
• NIOSHTIC Number:
  nn:20067791
• Citation:
  Environ Sci Technol 2022 Dec; 56(23):16611-16620
• Contact Point Address:
  Andrew P. Ault, Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
• Email:
  aulta@umich.edu
• Federal Fiscal Year:
  2023
• Performing Organization:
  University of North Carolina, Chapel Hill
• Peer Reviewed:
  True
• Start Date:
  20050701
• Source Full Name:
  Environmental Science and Technology
• End Date:
  20270630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:950a02aa712fb5283f2267e10f958330cf11c5f06d96f967462ad781b49579823d88ee98e92dec6910b06a4fedd19ca5bcb611fa6cf1934b6a7e376951c597d0
• Download URL:
  https://stacks.cdc.gov/view/cdc/230047/cdc_230047_DS1.pdf
• File Type:
  [PDF - 4.73 MB ]