【作者】 罗晓璐；

【导师】 沈学优； 朱利中；

【作者基本信息】 浙江大学 ， 环境化学， 2002， 硕士

【摘要】 本文评述了空气中挥发性有机化合物（VOCs）的研究进展。重点介绍了国内外对室内外空气中VOCs的污染现状、来源等研究概况以及人体接触VOCs的程度和健康风险评价；简要叙述了空气中VOCs的采集、前处理方法及分析方法。 建立了室内外空气中痕量苯系物（BTEX）采样分析方法。采用小体积、低噪声采样器，内装20～50目粒状活性炭的吸附采样管采集空气中的苯系物，二硫化碳解吸，火焰离子化检测器（FID）气相色谱法测定了空气中6种具有代表性的苯系物。该方法采样装置体积小、噪音低、操作简便；样品前处理方便，回收率高；样品测定准确，灵敏度高，选择性好，可重复分析；适合室内外空气中苯系物的采样分析。 调查了杭州市不同地区8户新装修家庭室内空气中具有代表性的苯系物的污染现状，结果发现杭州市家庭室内空气中苯系物污染较为严重。本文采集和分析了这8户家庭室内空气中苯系物的污染现状、来源及其影响因素。测得室内空气中苯的浓度为0.05～0.77mg／m³、甲苯的浓度为0.01～1.19mg／m₃、二甲苯的浓度为0.02～0.61mg／m₃，苯系物总浓度为0.11～2.57mg／m₃；苯系物污染十分严重，大大高于欧美和日本所测结果。装修家庭室内空气中甲苯的含量占苯系物总量的50％以上，其主要来源于室内装修过程中所使用的胶粘剂；苯和二甲苯主要来源于室内装饰用的涂料和油漆等化学品。 于2000年6月、2001年7月和2001年10月比较研究了杭州市环境空气中苯系物的浓度及季节变化趋势，结果表明，2001年7月城市空气中6种苯系物的平均浓度达37.96～222.55μg／m₃，明显高于2000年6月所测值（30.78～196.54μg／m₃）；2001年7月空气中苯系物总量达104.72μg／m₃，是2000室内外空气中苯系物的污染现状及来源研究 摘要年6月门0．79twin刁的1．5倍，苯系物污染有加重的趋势。在2001年各采样点空气中苯系物浓度为夏季＞秋季，其变化趋势和温度变化相同。在所有采样点甲苯的浓度均高于苯的浓度，为苯系物中的最高值，说明杭州市环境空气中苯系物主要来源子机动车尾气排放。更多还原

【Abstract】 Advances in research on volatile organic compounds (VOCs) in the ambient air are reviewed with 97 references. The general situation of VOCs’ survey in the ambient air and the origins of VOCs in the pollution of indoor and outdoor air are discussed emphatically. The sampling, clean-up and analytical methods of VOCs are described in brief. The indicators of personal exposures to VOCs and risk assessment of VOCs in the ambient air are particularly evaluated.An analytical method by gas chromatography (GC) for monitoring benzene and its alkyl derivatives in ambient air is proposed. This method consists of a little volume and low noise air sampling pump, solvent extraction and capillary gas chromatographic determination. Sampling of the benzene and its alkyl derivatives was carried out at a flow rate of 0.5L/min for 3 hours using a small low noise sampler, which was composed of an activated charcoal sampling tube (250mg in each layer). The benzene and its alkylbenzenes collected hi the activated charcoal were extracted with carbon disulfide by mechanical shaking for 20 min. The extract was then analyzed by capillary GC/FID, which was carried out at a flow rate of 30mL/min by highly pure nitrogen. The detector gas is hydrogen and air. The relative standard deviations (n=10) of the retention time and peak area were in the range of 0.36-0.81% and 1.14-3.23%, respectively, which were at BTEX concentration levels of 8.6-8.8 ug/mL with the linearly regressively factors being over 0.99. The detection limits ranged from 1.09~4.15ng when the maximum sampling measure was 180L. The recoveries of BTEX were 91.64?5.60%. Reproducibility and reliability of this method was proved to be excellent. Extraction procedure is simple and easy, and BTEX in many samples can be extracted in a short time. Separation and determination procedures by capillary gaschromatography and data processing system can operate routinely and automatically. The simple, easy, highly sensitive and reliable analytical method for BTEX can be applied to indoor and outdoor air pollution survey.The present situation of BTEX pollution in the indoor air of eight families, which were decorated recently, was investigated. The BTEX samples were collected from eight families, which BTEX pollution in the indoor air was more serious, and analyzed by GC in June 2000. The levels of total BTEX in the indoor air ranged from 0.11~2.57mg/m3, and the concentration of the benzene, toluene, o-, m- and p-ethyltoluenes was in the range of 0.05-0.77 mg/m3, 0.01-1.19 mg/m3, 0.02-0.61 mg/m3, respectively. And mean concentration of benzene which can cause human cancer was up to 0.24 mg/m3. The BTEX pollution was very serious and the concentration was much higher than Europe and Japan. More than 50% percent of the total BTEX was the toluene. As far as toluene was concerned, the main source was gooey used in indoor decorating. Benzene and o-, m- and p-ethyltoluenes originated from chemical compounds such as coating and paints.In order to study the seasonal variation of BTEX in the urban air of Hangzhou, the samples were collected in five sites from June 2000 to October 2001. In July 2001, the mean concentrations of BTEX were between 37.96-222.55 Mg/m3. It was much higher than that in June 2000 (30.78-196.54 Mg/m3). The total content of BTEX in the air in July 2001 was 104.72 Mg/m3, which was almost 1.5 higher than that in June 2000 (70.79 Mg/m3). And the concentrations of BTEX in ambient air show a distinct variation (summer>autumn), Consisting with temperature variation. The concentration of toluene in each site was higher than benzene and it was the highest. So the results indicated that exhaust gas letting off from motor vehicles was the main source of BTEX in ambient air in Hangzhou.更多还原