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Title: Real-world observations of reduced nitrogen and ultrafine particles in commercial cooking organic aerosol emissions

Abstract. Cooking is an important but understudied source of urban anthropogenic fine particulate matter (PM2.5). Using a mobile laboratory, we measured PM size and composition in urban restaurant plumes. Size distribution measurements indicate that restaurants are a source of urban ultrafine particles (UFPs, particles <100 nm mobility diameter), with a mode diameter <50 nm across sampled restaurants and particle number concentrations (PNCs, a proxy for UFPs) that were substantially elevated relative to the urban background. In our observations, PM mass emitted from restaurants was almost entirely organic aerosol (OA). Aerosol mass spectra show that while emissions from most restaurants were similar, there were key mass spectral differences. All restaurants emit OA at m/z 41, 43, and 55, though the composition (e.g., the ratio of oxygenated to reduced ions at specific m/z) varied across locations. All restaurant emissions included reduced-nitrogen species detected as CxHyN+ fragments, making up ∼15 % of OA mass measured in plumes, with reduced molecular functionalities (e.g., amines, imides) that were often accompanied by oxygen-containing functional groups. The largest reduced-nitrogen emissions were observed from a commercial bread bakery (i.e., 30 %–50 % of OA mass), highlighting the marked differences between restaurants and their importance for emissions of both urban UFPs and reduced nitrogen.

 
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Award ID(s):
2011362
NSF-PAR ID:
10493765
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Copernicus
Date Published:
Journal Name:
Atmospheric Chemistry and Physics
Volume:
24
Issue:
2
ISSN:
1680-7324
Page Range / eLocation ID:
1281 to 1298
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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