Ji, Yaqin, Xiao, Yang, Wang, Miao, Wang, Bingbing, Yang, Xiawei, Shi, Jingwen, Xu, Wenju, Yang, Wen, and Zhao, Xueyan
Statistical data indicate that Xinjiang is having the second-highest particulate matter emissions in China over the past two years, yet relevant research data are scarce. PM 10 includes a variety of toxic organic substances, including nitro-PAHs (NPAHs) and oxy-PAHs (OPAHs). The objective of this study was to characterize and ascertain the sources of PM 10 -bound NPAHs and OPAHs in the core area of the Ili River Valley. To analyze 18 NPAHs and 5 OPAHs, gas chromatography-mass spectrometry (GC-MS) was employed, revealing median concentrations of 449.09 pg/m3 for Σ 18 NPAHs and 9.38 ng/m3 for Σ 5 OPAHs. The levels of NPAHs and OPAHs were higher in the heating season (Σ 18 NPAHs: 641.97 pg/m3; Σ 5 OPAHs: 16.41 ng/m3) than in the non-heating season (Σ 18 NPAHs: 268.68 pg/m3; Σ 5 OPAHs: 2.61 ng/m3) in the core area of the Ili River Valley. During the heating season, concentrations were higher in urban areas than in rural areas, with the reverse trend noted in the non-heating season. Source apportionment, conducted through the characteristic ratio method and positive matrix factorization (PMF), identified coal/biomass combustion as the primary source of NPAHs and OPAHs. Moreover, the increase in inhalation and dermal contact lifetime cancer risk (ILCR) values for all sampling sites, seasons, and age categories within the core area of the Ili River Valley ranged from 2.05E-11–5.02E-08, 7.59E-13–1.26E-09, respectively. These values were all below 10–6, suggesting the absence of carcinogenic risk from exposure to these contaminants. • Coal/biomass combustion serves as the main source of NPAHs and OPAHs in PM 10. • Significant increases in the levels of Σ 18 NPAHs and Σ 5 OPAHs occurred in winter. • There were no carcinogenic risks from inhalation intake and dermal contact in the core area of the Ili River Valley. [ABSTRACT FROM AUTHOR]