乌鲁木齐市河滩快速路交通干线空气中挥发性有机物污染特征及健康风险评估OA

To investigate the impact of volatile organic compounds(VOCs)from urban traffic on air quality and public health,a fixed sampling site was established adjacent to the Hetan Expressway in Urumqi from March to December 2025.The 116 VOCs were monitored across four seasons using Summa canister sampling coupled with gas chromatography-mass spectrometry(GC-MS).The results showed that 81 VOCs were qualitatively detected,with total VOC(TVOCs)concentrations ranging from 19.55 to 44.08 μg/m3.A significant seasonal variation was observed,with the highest TVOCs concentration in winter and the lowest in summer,primarily attributed to frequent temperature inversions,a lower atmospheric boundary layer,and increased pollutant emissions due to reduced combustion efficiency of motor vehicles at low temperatures.Alkanes were the dominant group,contributing 30.2%～43.2%of TVOCs,followed by alkenes/alkynes and aromatics.Tracer pollutant source apportionment indicated that the toluene/benzene ratio and the toluene/3-methylpentane ratio were highly consistent with the source profile of vehicle exhaust,confirming that VOCs were mainly derived from vehicular emissions.The ozone formation potential(OFP)ranged from 36.99 to 127.61 μg/m3,peaking in winter,with alkenes contributing 47%～65%and ethylene being the most prominent contributor.The health risk assessment showed that the non-carcinogenic hazard index(HI)for all seasons remained below 1;however,the lifetime carcinogenic risk of benzene in winter reached 2.39×10-6 exceeding the acceptable level(1×10-6).This study characterized the VOC pollution profile along the Hetan Expressway and provided a scientific basis for precise prevention and control of traffic pollution.