[Character of volatile carbonyl compounds and their source in Guangzhou ambient air].

Characterizations and their primary sources of 17 carbonyls compounds in the serious air polluted summer-days of 2006 were studied by DNPH-HPLC-UV measurement methods. Results were shown as follows, acetone was found to be the most predominant carbonyls followed by formaldehyde, 2-butone and acetaldehyde, with the 24 h average concentrations of 10.84, 9.29, 8.35, 8.0 microg x m(-3) respectively, which accounted for 72.29% of total carbonyl compounds in the atmosphere. Among the four sites, the highest level of total carbonyl compounds was 59.66 microg x m(-3) at the urban site of Guangdong Provincial Centre of Environmental Monitor, the lowest was 43.51 microg x m(-3) at the rural site of Conghua. Different variation characterizations of each carbonyl compounds at there different height sites were found, and the diurnal variation was shown that the total concentration of carbonyl compounds in daytime was much higher than that of nighttime. Good correlations between formaldehyde, acetaldehyde and acetone indicated that they mainly derived from the same sources, and the value that C1/C2 and C2/C3 ratios were 1.12 and 7.51 respectively implied that the important pollution sources of carbonyl compounds was vehicular exhaust in Guangzhou.