Seasonal, diurnal and nocturnal variations of carbonyl compounds in the semi-urban environment of Orléans, France

Seasonal Trends of Formaldehyde and Acetaldehyde in the Megacity of São Paulo

“…This pattern was similar to that observed in the city of Londrina, located in the state of Paraná (Table 3), where the concentrations of formaldehyde and acetaldehyde have been found to be higher in winter [29]. However, the pattern observed in the present study differed from those reported in studies conducted in urban areas in China and France [30][31][32][33], where the summer/winter, autumn/winter, and spring/winter ratios were often higher than 1.0 for formaldehyde and acetaldehyde, indicating that their concentrations were lower in winter. The concentrations of atmospheric formaldehyde and acetaldehyde were often higher in winter than in other seasons, in accordance with the meteorological conditions, given that vehicle emissions can be considered constant all over the year.…”

“…The most well-known and well-established method for collecting gas-phase carbonyl compounds is the 2,4-dinitrophenylhydrazine (2,4-DNPH) technique. The sampling and analyses used in the 2,4-DNPH technique follow the standard US EPA TO-11A method [25], and the technique has been largely applied in different places and field campaigns [26][27][28][29][30][31][32][33][34], as well as in previous campaigns carried out in the MASP [35][36][37][38]. It is based on the specific reaction of carbonyl compounds to 2,4-DNPH in the presence of a strong acid, as a catalyst, to form stable color hydrazone derivatives [25], which are then identified by high performance liquid chromatography (HPLC) with ultraviolet detection.…”

Determination and Characteristic Analysis of Atmospheric Carbonyl Compounds in a North China Plain Hub City

“…A higher C1/C2 ratio implies that the photooxidation of natural hydrocarbons such as isoprene yields more formaldehyde than acetaldehyde [31]. In the present study, the average C1/C2 ratio was 1.90, higher than that in island (1.36) [32], and was similar to that (1.79) in Shanghai [27] and Beijing (1.59) [33], but lower than that in Orléans (2.44) [12], Hong Kong (UST) (2.86) [34], and forested regions (Cibola National Forest, U.S. and Zhangjiajie, China) [11,35], implying that anthropogenic sources are the main source of carbonyl compounds in the eastern part of urban Jinan.…”

“…The unit has been converted from ppbv to μg•m -3 since no molar concentrations were expressed in the reference papers [19]. The concentrations of formaldehyde and acetaldehyde in Jinan were comparable with that in Hong Kong [20], but higher than that in foreign cities (in Spain and France) [12,21]. It was also higher than coastal cities such as Qinzhou and Yantai [22,23] of China.…”

“…Because of the negative environmental and health effects, carbonyl compounds have been of wide concern [8][9][10][11], Jiang et al [12] studied the concentration levels and variations of carbonyl compounds in Orléans, France (a semi-urban site), while Wang et al [2] analyzed the source of carbonyl compounds in a rural area of the Yangtze River Delta. At present, most domestic studies in China have focused on the Yangtze River Delta, Pearl River Delta and Beijing City.…”