Pollution characteristics and health risk assessment of volatile organic compounds in Hefei urban area

The ambient VOCs were monitored in the urban area of Hefei city during four seasons in 2016. They were analyzed using an off-line analysis method of SUMMA cannister sampling and gas chromatography-mass spectrometer（GC-MS）. The VOCs results show that 48 VOCs are identified in the air samples including alkane, arene, halohydrocarbon, etc. The annual mean concentration of total VOCs (TVOCs) is 15.61×10-9, the largest one reaching 47.64×10-9. The seasonal variation of TVOCs in this area is obvious, and the order is winter>spring>autumn>summer; the daily mean concentration of TVOCs shows a trend of concentrations being higher in the morning and in the evening, and lower at noontime. Non-carcinogenic risk indexes of VOCs are below 1, which would not cause non-carcinogenic health hazards to exposed populations. However，the cancer risk index exposed to carcinogenic VOCs is higher than the suggested value of USEPA(U. S. Environmental Protection Agency)( 1×10-6 ), which could indicate a relatively higher cancer risk.