Size distributions of n-alkanes, fatty acids and fatty alcohols in springtime aerosols from New Delhi, India.
Environ Pollut
; 219: 957-966, 2016 Dec.
Article
in En
| MEDLINE
| ID: mdl-27751634
ABSTRACT
Size-segregated aerosol samples were collected in New Delhi, India from March 6 to April 6, 2012. Homologous series of n-alkanes (C19C33), n-fatty acids (C12C30) and n-alcohols (C16C32) were measured using gas chromatography/mass spectrometry. Results showed a high-variation in the concentrations and size distributions of these chemicals during non-haze, haze, and dust storm days. In general, n-alkanes, n-fatty acids and n-alcohols presented a bimodal distribution, peaking at 0.7-1.1 µm and 4.7-5.8 µm for fine modes and coarse modes, respectively. Overall, the particulate matter mainly existed in the coarse mode (≥2.1 µm), accounting for 64.8-68.5% of total aerosol mass. During the haze period, large-scale biomass burning emitted substantial fine hydrophilic smoke particles into the atmosphere, which leads to relatively larger GMDs (geometric mean diameter) of n-alkanes in the fine mode than those during the dust storms and non-haze periods. Additionally, the springtime dust storms transported a large quantity of coarse particles from surrounding or local areas into the atmosphere, enhancing organic aerosol concentration and inducing a remarkable size shift towards the coarse mode, which are consistent with the larger GMDs of most organic compounds especially in total and coarse modes. Our results suggest that fossil fuel combustion (e.g., vehicular and industrial exhaust), biomass burning, residential cooking, and microbial activities could be the major sources of lipid compounds in the urban atmosphere in New Delhi.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Particle Size
/
Aerosols
/
Air Pollutants
/
Alkanes
/
Fatty Acids
/
Fatty Alcohols
Country/Region as subject:
Asia
Language:
En
Journal:
Environ Pollut
Journal subject:
SAUDE AMBIENTAL
Year:
2016
Type:
Article
Affiliation country:
China