新疆博斯腾湖地区大气PM_(10)中多环芳烃的污染特征、来源及健康风险评价

Pollution,Sources,and Health Risk Assessment of PM_(10)-bound Polycyclic Aromatic Hydrocarbons in Bosten Lake Area,Xinjiang

为了解中国西部干旱区域博斯腾湖地区大气颗粒物中多环芳烃(PAHs)的污染水平和健康风险,本研究于2016年采暖期和2017年非采暖期,在该地区博湖县和周边的塔中采集了可吸入颗粒物(PM_(10))样品,使用气相色谱-质谱联用仪(GC-MS)测定PM_(10)中美国环境保护署(USEPA)优先控制的16种多环芳烃(PAHs)的浓度,分析其污染特征、来源及其对人群的健康风险。结果表明,博湖县采暖期大气PM_(10)中PAHs浓度显著高于非采暖期,分别为47.63±29.00 ng/m^(3)和3.24±1.05 ng/m^(3);塔中地区在采暖期和非采暖期未表现出明显的季节差异,且污染水平较低,分别为2.13±0.90 ng/m^(3)和1.89±0.23 ng/m^(3)。研究区大气PM_(10)中PAHs以中高环为主,采暖期以荧蒽(Flua)、芘(Pyr)、苯并[b]荧蒽(BbF)和[艹屈](Chr)为主要污染单体,非采暖期以菲(Phe)、荧蒽(Flua)、茚并[1,2,3-cd]芘(IcdP)和苯并[g,h,i]苝(BghiP)为主。源解析结果表明,燃烧源对博湖县和塔中PAHs贡献最大,分别为82.54%和61.13%。轨迹分析表明新疆北部和塔里木盆地西部排放的PAHs可通过大气传输对博斯腾湖地区造成影响。健康风险评估结果表明,博湖县采暖期大气PM_(10)中PAHs对各类人群的终生致癌风险(ILCR)值均处于10^(-6)~10^(-4),对人体具有潜在致癌风险。

To understand the pollution level and human health risk of polycyclic aromatic hydrocarbons(PAHs)in atmospheric particles in the Bosten Lake area,a semi-arid region in western China,inhalable particles(PM_(10))samples were collected from Bohu county and Tazhong during the heating period in 2016 and non-heating period in 2017.In PM_(10),16 PAHs,which are prioritized for control by the US Environmental Protection Agency(USEPA),were quantified with gas chromatography mass spectrometry(GC-MS).With the aim to analyze their pollution,sources,and health risks to the population.The results showed that the concentrations of PM_(10)-bound PAHs in Bohu county were significantly higher during the heating period(47.63±29.00 ng/m^(3))than the non-heating period(3.24±1.05 ng/m^(3)).In comparison,the concentrations of PM_(10)-bound PAHs in Tazhong(2.13±0.90 ng/m^(3) in the heating period and 1.89±0.23 ng/m^(3) in the non-heating period)were remarkably lower than Bohu country,without significant seasonal variation.Medium and high cyclic PAHs predominated the PM_(10)samples in the study areas,with fluoranthene(Flua),pyrene(Pyr),benzo[b]fluoranthene(BbF)and chrysene(Chr)as the major pollutants during the heating period and phenanthrene(Phe),fluoranthene(Flua),indeno[1,2,3-cd]pyrene(IcdP)and benzo[g,h,i]perylene(BghiP)during the non-heating period.The source analysis points out that combustion was the biggest source,accounting for 82.54% and 61.13% of total PAHs emissions in Bohu country and Tazhong.The trajectory analysis demonstrates that PAHs emission from northern Xinjiang and the western Tarim Basin can affect Bosten Lake area through atmospheric transport.The health risk assessment highlights the potential carcinogenic risk for residents in Bohu county,according to the lifetime carcinogenic risk(ILCR)values of PAHs in PM_(10)valued 10^(-6)~10^(-4)for all groups of people during the heating period.