[Seasonal variations of carbonyl compounds in urban atmosphere of Beijing].
A passive diffusive sampling device (DSD-DNPH) was used to collect C1-C10 carbonyl compounds among five sampling sites in the urban area of Beijing among August 19-22 (summer), October 24-30 (autumn), 2006 and January 20-23 (winter), 2007. Through the analysis of sampled carbonyl compounds by High Performance Liquid Chromatography (HPLC), 20 carbonyl compounds were measured and total concentrations were (89.1 +/- 23.6), (85.2 +/- 17.5) and (40.0 +/- 9.8) microg/m3 in summer, autumn and winter, respectively. Among the 20 carbonyl compounds, formaldehyde, acetaldehyde and acetone were the most abundant compounds. The concentrations of them increased to (15.3 +/- 9.2), (12.9 +/- 4.9) and (13.3 +/- 3.5) microg/m3 in summer, and (13.2 +/- 4.0), (13 +/- 4.4) and (15.3 +/- 4.0) microg/m in autumn from (7.1 +/- 2.1), (10.3 +/- 3.1) and (9.5 +/- 1.8) microg/m3 in winter. Vehicular emissions become the most significant source of carbonyl compounds in winter, while the photochemical reactions and cooking exhaust also play important roles during summer and autumn. In addition, the dispersion conditions have significant effects on the concentration of carbonyl compounds, for the concentrations of the main carbonyl compounds such as formaldehyde, acetaldehyde and acetone, especially, are much lower under good dispersion conditions than bad ones.
Xu
Jia-Yu
JY
Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China. jiayu-xu@tsinghua.edu.cn
Gao
Yang
Y
D000079:Acetaldehyde / Q000032:analysis*; D000096:Acetone / Q000032:analysis*; D000393:Air Pollutants / Q000032:analysis*; D002681:China; D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring; D005557:Formaldehyde / Q000032:analysis*; D012621:Seasons; D014504:Urban Health; D001335:Vehicle Emissions / Q000032:analysis
D000393:Air Pollutants; D001335:Vehicle Emissions; D000096:Acetone; D005557:Formaldehyde; D000079:Acetaldehyde