Polycyclic aromatic hydrocarbons and nitropolycyclic aromatic hydrocarbons in urban air particulates and their relationship to emission sources in the Pan–Japan Sea countries

Factors affecting atmospheric 1-, 2-nitropyrenes and 2-nitrofluoranthene in winter at Noto peninsula, a remote background site, Japan

“…These values were better than the values obtained by the previous system. For example, the previous detection limit of 1-NP was 10 fmol (Tang et al, 2005). The calibration curves were straight in the ranges from 10 fmol to 10 pmol (2-NFR), from 50 fmol to 50 pmol (2-NP) and from 5 fmol to 10 pmol (1-NP), respectively, with correlation coefficients over 0.999 and RSDs less than 5% (Hayakawa et al, 2011).…”

“…Atmospheric NPAHs originate from imperfect combustion of organic matter, such as 1-NP, and are usually higher in winter than in summer in several cities in East Asia (Kakimoto et al, 2000(Kakimoto et al, , 2002Hattori et al, 2007;Tang et al, 2002Tang et al, , 2005. Possible causes for the seasonal variation include enhanced emissions from residential and/or commercial heating and the formation of a temperature inversion in the boundary layer in winter, and photochemical degradation of NPAHs in summer (Fan et al, 1996;Fujitani, 1986;tang et al, 2005).…”

“…By comparing the median winter [2-NFR]/[1-NP] ratio at WAMS with that at downtown Shenyang, which is located on the air transportation route to WAMS, and on a main road in Kanazawa, 80 km south of WAMS, the value at WAMS (2.3, n = 22) was very close to the value at downtown Shenyang (2.2, n = 5: TSP were collected from Jan. 26 to Feb. 10, 2010, data are not published) and was significantly larger than that on the main road in Kanazawa (0.9, n = 8, p < 0.01: TSP were collected from Jan. 21 to 29, 2008, data are not published). Furthermore, according to our previous studies (Hattori et al, 2007;Tang et al, 2005), the main contributors of NPAHs, except for 2-NP and 2-NFR, and PAHs in winter were motor vehicles in Japanese commercial cities such as Tokyo, Sapporo and Kanazawa, while they were coal heating systems and factories in the cities of Northeast China such as Shenyang, Fushun and Tieling.…”

“…Possible causes for the seasonal variation include enhanced emissions from residential and/or commercial heating and the formation of a temperature inversion in the boundary layer in winter, and photochemical degradation of NPAHs in summer (Fan et al, 1996;Fujitani, 1986;tang et al, 2005). However, in some parts of Japan and the United States, the concentrations of 2-NFR and/or 2-NP are lower in winter than in warmer seasons (Bamford and Baker, 2003;Kameda et al, 2004;Murahashi et al, 1999;Reisen and Arey, 2005).…”

“…Our studies in this region over the past 15 years have shown that the main contributors to the atmospheric PAHs and NPAHs were automobiles, especially diesel-engine vehicles in Japanese cities (Tokyo, Sapporo, Kanazawa and Toyama) and Seoul, Korea, and coal combustion processes in Shenyang, Fushun and Tieling, China, and Vladivostok, Russia. Atmospheric concentrations of PAHs were 3 -180 times higher in Chinese and Russian cities than in Japanese and Korean cities (Kakimoto et al, 2000(Kakimoto et al, , 2002Hattori et al, 2007;Tang et al, 2002Tang et al, , 2005, mainly because of the large consumption of coal in China and Eastern Russia (Tang et al, 2005;Chen et al, 2005).…”