大学校园室内BTEX浓度水平变化规律及健康风险

Concentration,Variation and Risk Assessment of BTEX in the Indoor Air of a University Campus

采用Tenax-TA吸附/热脱附-气相色谱法(TD-GC)对大学校园室内外空气中5种苯系物(BTEX,苯、甲苯、乙苯、间/对-二甲苯和邻二甲苯)的平均浓度进行了检测。检测结果显示,5种苯系物的平均浓度均低于国家标准值。被测空气的苯系物中甲苯所占比例最大,为27.9%～32.0%。室内BTEX浓度稍高于室外,多数采样点的室内浓度与室外浓度比值(CI/CO)大于1.0。通风可有效降低空气中苯系物浓度。大学校园室内空气中的苯对学生的致癌风险为3.67×10-7～1.09×10-6。

Average concentrations of five BTEX compounds including benzene,toluene,ethylbenzene,m,p-xylenes and o-xylene in indoor and outdoor air samples collected from a university campus were determined by thermal desorption and gas chromatography（TD-GC） coupled systems.Results showed that all concentrations of benzene,toluene and the xylenes met the indoor air quality standard of China.Average concentrations of toluene accounted for the largest percent（27.9%～32.0%）of the 5 compounds determined.The indoor concentrations of BTEX were a little higher than their outdoor counterparts.The ratios of indoor/outdoor（I/O） BTEX concentrations were more than 1.0 in most sampling sites.The BTEX pollution attribute to ventilation helps to reduce BTEX concentration in air.The cancer risk of BTEX in university campus was ranged from 3.67×10-7 to 1.09×10-6.