中文摘要：

采用预浓缩色质联用系统对广州市4家医院室内外空气中5种苯系物（BTEX，即苯、甲苯、乙基苯、间/对一二甲苯、邻一二甲苯）进行了检测．结果表明，4家医院的5种BTEX的总浓度平均值为10．61-253．35μg／m^3．5种BTEX中，以甲苯的浓度最赢但均低于国家室内空气质量标准的阈值.也低于国外医院室内空气BTEX的浓度．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（I/O）大于1．0．除苯外，其他4种BTEX之间的相关性比较好,表明它们有共同的来源．主成分分析结果表明，医院室内空气中BTEX的来源包括室内装修材料及汽车尾气．

英文摘要：

Five BTEX compounds （including benzene, toluene, ethylbenzene, m,p-xylenes and o-xylenes） in indoor and outdoor air samples collected from four hospitals of Guangzhou were determined by the preconcentrator-GC/MS system. The average of sum concentrations of five BTEX varied from 10.61 to 253.35μg/m^3. Toluene was the most abundant BTEX. All concentrations of benzene, toluene and xylenes met the Indoor air quality standard of China, and were lower than those observed in the hospitals of other countries. The indoor concentrations of BTEX were a little higher than their outdoor counterparts. The ratios of indoor/outdoor （I/O） BTEX concentrations were 〉1.0 in most sampling sites. The strong correlations among the four BTEX （except benzene） indicated that they might have common sources. Furthermore, the results of principal component analysis （PCA） showed that BTEX in indoor air of Guangzhou hospitals might derive from decoration materials and vehicular exhaust.