Secondary Formation and Impacts of Gaseous Nitro-Phenolic Compounds in the Continental Outflow Observed at a Background Site in South China.
Environ Sci Technol
; 56(11): 6933-6943, 2022 06 07.
Article
en En
| MEDLINE
| ID: mdl-34732048
ABSTRACT
Nitro-phenolic compounds (NPs) have attracted increasing attention because of their health risks and impacts on visibility, climate, and atmospheric chemistry. Despite many measurements of particulate NPs, the knowledge of their gaseous abundances, sources, atmospheric fates, and impacts remains incomplete. Here, 18 gaseous NPs were continuously measured with a time-of-flight chemical ionization mass spectrometer at a background site in South China in autumn and winter. Abundant NPs were observed in the continental outflows from East Asia, with a total concentration up to 122.1 pptv. Secondary formation from the transported aromatics dominated the observed NPs, with mono-NPs exhibiting photochemical daytime peaks and nighttime enrichments of di-NPs and Cl-substituted NPs. The budget analysis indicates that besides the â¢OH oxidation of aromatics, the NO3⢠oxidation also contributed significantly to the daytime mono-NPs, while the further oxidation of mono-NPs by NO3⢠dominated the nocturnal formation of di-NPs. Photolysis was the main daytime sink of NPs and produced substantial HONO, which would influence atmospheric oxidation capacity in downwind and background regions. This study provides quantitative insights on the formation and impacts of gaseous NPs in the continental outflow and highlights the role of NO3⢠chemistry in the secondary nitro-aromatics production that may facilitate regional pollution.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Gases
/
Nitrocompuestos
País/Región como asunto:
Asia
Idioma:
En
Revista:
Environ Sci Technol
Año:
2022
Tipo del documento:
Article
País de afiliación:
China