Nontargeted Tandem Mass Spectrometry Analysis Reveals Diversity and Variability in Aerosol Functional Groups across Multiple Sites, Seasons, and Times of Day

• DOI: 10.1021/acs.estlett.9b00702
• Publication Date: 2020-01-13T14:50:13Z
• Authors: Jenna C. Ditto; Taekyu Joo; Jonathan H. Slade; Paul B. Shepson; Nga L. Ng; Drew R. Gentner
• Keywords: Functional group

Organic aerosol (OA) is a complex mixture of compounds with diverse elemental and structural features, its composition affects health environmental impacts. A detailed speciation the functional group distribution in OA important for constraining atmospheric reaction pathways products, evaluating chemical mechanisms models, understanding We used high-resolution tandem mass spectrometry to perform nontargeted analysis groups from three ambient sites across times day seasons. observed range oxygen-, nitrogen-, and/or sulfur-containing groups, including oxygenates such as hydroxyls (29–69%) carboxylic acids (19–59%), that dominated may participate hydrogen bonding thus impact physical properties (percentages indicate average ion abundance contributions campaigns). also esters (7–39%) ethers (13–42%) suggest importance oligomerization. On average, organonitrates represented only 12% identified nitrogen-containing organosulfates 21% while we many other nitrogen- structures were contributors (e.g., amines, imines, nitrophenols, sulfides). Most (81%) multifunctional likely multigenerational oxidation which typically contained two five total.