Long-Term Trends in Urban Atmospheric Polycyclic Aromatic Hydrocarbons and Nitropolycyclic Aromatic Hydrocarbons: China, Russia, and Korea from 1999 to 2014

Abstract

Total suspended particulate matter (TSP) was collected during the summer and winter in five cities in China (Shenyang, Beijing, and Shanghai), Russia (Vladivostok), and Korea (Busan) from 1997 to 2014. Nine polycyclic aromatic hydrocarbons (PAHs) with four to six rings, including pyrene (Pyr) and benzo[a]pyrene (BaP), were determined using high-performance liquid chromatography with fluorescence detection. Two nitropolycyclic aromatic hydrocarbons (NPAHs), 1-nitropyrene (1-NP) and 6-nitrobenzo[a]pyrene (6-NBaP), were also determined using high-performance liquid chromatography with online reduction/chemiluminescence detection. Two Chinese cities, Beijing and Shenyang, showed very high concentrations of total PAHs (ΣPAH) and total NPAHs (ΣNPAH) with a large seasonal difference (winter > summer), although the concentrations decreased over time. In both cities, maximum mean concentrations of ΣPAH over 200 ng m−3 were observed in the winter. In Beijing, an increase in the ΣPAH concentration was observed in the winter of 2010, which was after the 2008 Beijing Olympic Games. The [1-NP]/[Pyr] ratio, a diagnostic parameter for source, was smaller in the winter than in the summer over the monitoring period, suggesting a large contribution of coal heating systems in the winter. In Vladivostok, concentrations of ΣPAH and ΣNPAH were lower than in the above two Chinese cities. The [1-NP]/[Pyr] ratio was larger than in the above Chinese cities even in the winter, suggesting that the contribution of coal combustion facilities, such as power plants for heating, was not very large. In Shanghai and Busan, concentrations of ΣPAH and ΣNPAH were much lower than in the above three cities. At the beginning of the monitoring periods, the [1-NP]/[Pyr] ratios, which were as large as those of Japanese commercial cities, suggested a large contribution from automobiles. After that, the contribution of automobiles decreased gradually. However, BaP concentrations were still over 1 ng m−3 in all cities monitored in China, Russia, and Korea, suggesting that the urban air pollution of PAHs and NPAHs in these regions should not be ignored.

Multi-Year Concentrations, Health Risk, and Source Identification, of Air Toxics in the Venice Lagoon

“…PAHs concentration in PS and MM were lower than that measured in a long-term monitoring study in the United States (Liu et al, 2017) and in an 1-year study in India (Kumar et al, 2020). The period of sampling could highly influence the concentration of PAHs (Hayakawa et al, 2020), since one of the most important anthropogenic source of PAHs is the primary emissions from residential heating, especially biomass burning, during the cold season (Tomaz et al, 2016). Moreover, the high concentration of pollutants in the cold season could also be due to the variation of the thickness of the planetary boundary layer (PBL), the volume of air where the atmospheric pollutants are dispersed.…”

PM-Bound Polycyclic Aromatic Hydrocarbons and Nitro-Polycyclic Aromatic Hydrocarbons in the Ambient Air of Vladivostok: Seasonal Variation, Sources, Health Risk Assessment and Long-Term Variability

“…Nevertheles, there was a significant increasing trend during both seasons in 2010 and summer in 2017. Based on our previous research, according to the Asia Pacific Economic Cooperation (APEC) meeting in 2012, many infrastructure construction projects were under construction in Russia from 2007 to 2012, which may have led to an increase in the concentration of PAHs [ 25 ]. In addition, the Russia–China naval activities in the Sea of Japan and the Sea of Okhotsk in September 2017 [ 73 ] may have led to an increase in ∑PAHs, and the impact of these emergencies on PAHs cannot be ignored.…”

“…The residential heating period lasts appromixmately six months every year. Our previous study in Vladivostok demonstrated that coal combustion was the major source of ambient PAHs and NPAHs in winter [ 25 , 26 ]. This study also showed that human activities and local government energy policies directly influence the concentrations and compositions of PAHs and NPAHs.…”

Impact of the COVID-19 Outbreak on the Long-range Transport of Particulate PAHs in East Asia

“…In 2018, China accounted for 24% of global energy consumption of which coal and oil accounted for 58% and 18.9%, respectively (bp p.l.c., 2019;NBSC, 2019). As a result, the concentration of atmospheric PAHs in China is much higher than that of some Asian, European and American countries (Sanderson et al, 2004;Delhomme and Millet, 2012;Shen et al, 2013;Tang et al, 2017;Zhang et al, 2019a;Hayakawa et al, 2020), although strict air pollution control measures instituted by China have effectively improved air quality in recent years (Zheng et al, 2018;Zhang et al, 2019c).…”