地下停车场内挥发性有机物变化特征、来源及人体健康风险评估:以北京市某一地下停车场为例

采集北京市某一地下停车场内环境空气样品，利用气相色谱-质谱/氢火焰离子化检测器(GCMSD/FID)测定了挥发性有机物(VOCs)的组成，分析其浓度特征、组分特征和影响因素，运用特征物种比值法和正定矩阵因子分析模型(PMF)解析VOCs来源，采用健康风险评估模型定量评估部分VOCs的健康风险.结果表明，地下停车场内VOCs平均浓度为514.16μg·m^-3，其中烷烃占比最大(43.76%)，其次是芳香烃(28.89%)、烯烃(10.97%).影响停车场内VOCs浓度的主要因素包括机动车运行工况、机动车进出车次及扩散条件.冷启动工况、较多的出入车次和不利的扩散条件会导致VOCs浓度显著上升.苯/乙苯和苯/甲基叔丁基醚(MTBE)的均值分别为1.5和0.8，表明机动车尾气和汽油挥发是地下停车场内VOCs的主要来源. PMF解析结果表明地下停车场内VOCs的首要来源为机动车尾气源(44.58%)，汽油挥发源和汽车内饰挥发源分别贡献24.56%和9.18%.其中，汽油挥发源在08:00—10:00时段贡献最大，机动车尾气源在16:00—18:00时段贡献最大.健康风险评估...     

中国典型沿海城市冬季PM2.5中碳组分的污染特征及来源解析

为研究中国典型沿海城市冬季PM_2.5中碳组分的污染特征及来源,于2018年12月5日—2019年1月30日分别在天津(TJ)、上海(SH)和青岛(QD)同步采集PM_2.5样品。结果表明,天津、上海和青岛PM_2.5的平均浓度分别为(116.96±66.93)、(31.21±25.62)、(74.93±54.60)μg·m^-3,OC和EC的空间分布均为天津(18.69±7.95)μg·m^-3和(4.98±2.08)μg·m^-3>青岛(16.45±8.94)μg·m^-3和(2.01±1.04)μg·m^-3>上海(7.28±3.11)μg·m^-3和(1.05±1.25)μg·m^-3。3个站点的OC和EC均呈现较好的相关性,表明OC和EC具有相似的来源;OC/EC比值范围在2.37—7.53、5.47—46.41和4.77—13.36之间,证明各采样点均存在二次有机碳(SOC)的生成;采用最小R²法(MRS)估算SOC浓度,得到3个采样点SOC的平均质量浓度为(5.09±4.68)、(3.90±1.65)、(4.21±4.31)μg·m^-3,分别占OC总量的27.2%、55.8%和19.5%,其中上海的SOC在OC中的占比最大,说明上海二次有机碳污染较为严重,这主要归因于冬季严重污染源排放和有利的二次转化气象条件,而天津和青岛的碳组分主要来自污染源的直接排放。主成分分析(PCA)结果发现,天津PM_2.5中碳组分主要来源于道路尘、生物质燃烧和机动车尾气,上海PM_2.5中碳组分主要来源于生物质燃烧、道路扬尘和机动车尾气。青岛PM_2.5中碳组分主要来源于道路扬尘、机动车尾气。后向轨迹聚类分析表明,来自西北方向的气团对天津的影响较大,PM_2.5和碳组分的浓度值最大;而对上海而言,主要受北方气溶胶经过海面又传输回上海的气团的影响;青岛站点主要受华北地区污染物和本地排放源的影响。     

太原市不同功能区环境空气中挥发性有机物特征与来源解析

采集太原市3个不同功能区夏季和冬季环境空气样品,使用色谱-质谱仪测定挥发性有机物(VOCs)的组成,分析VOCs浓度变化和日变化特征,计算臭氧生成潜势(OFP),利用特征比值法和正定矩阵因子分析法(PMF)研究环境空气中VOCs的来源.结果表明,观测期间太原市环境空气中VOC总浓度变化范围为(36.27—210.67)μg·m~(-3),夏季和冬季VOCs化合物平均质量浓度为49.73μg·m~(-3)和205.19μg·m~(-3),冬季环境空气中VOCs浓度是夏季VOCs的4.13倍;VOCs日变化受到机动车排放和光化学反应显著影响,且夏季影响大于冬季;夏季OFP最大的物种为烯烃类化合物,冬季OFP最大的物种为芳香烃类化合物.太原市环境空气中VOCs主要包括五类污染源,分别为燃煤源28.10%、机动车源27.41%、挥发源22.90%、液化石油/天然气源14.90%和植物源6.69%;不同功能区主要污染源存在差异,太原市夏季工业交通区最主要排放源为燃煤源,居民商业混合区和居民交通区受燃煤源和机动车排放源共同影响,冬季太原市燃煤源是环境空气中VOCs的最主要污染源.     

成都市餐饮源VOCs排放特征

为研究成都市餐饮源VOCs排放特征,建立成都市餐饮源114种VOCs成分谱,本研究选择11个监测对象进行VOCs组分分析,并探索餐饮源VOCs全组分特征.结果表明,餐饮源VOCs中烷烃占比为23.12%—30.29%,烯烃占比为8.61%—25.78%,芳香烃占比为0.16%—5.86%,卤代烃占比为0.86%—13.82%,OVOCs占比为28.02%—63.77%,其他占比为2.02%—8.26%. OVOCs、烷烃和烯烃3类占比最高,3类污染物累计质量浓度百分比在75%以上,是餐饮源重要的污染物类型.餐饮源排名前10的VOCs分别是丙烯醛(11.12%)、乙烷(9.87%)、乙醛(9.51%)、丙酮(9.34%)、乙烯(7.86%)、正戊烷(5.74%)、乙炔(5.01%)、丁二烯(4.64%)、顺式-1,3-二氯-1-丙烯(3.40%)和乙酸乙酯(3.04%),是餐饮源的特征污染物.餐饮源全组分分析得到OVOCs的代表性物质为反式茴香脑和芳樟醇等,烯烃代表性物质为长叶烯和柠檬烯等,烷烃代表性物质为正十五烷和正庚烷等,为完善餐饮源成分谱物种、探寻餐饮源特征污染物的研究提供参考.采...     

朔州市夏季环境空气中VOCs的污染特征及来源解析

采集夏季朔州市环境空气中挥发性有机物(VOCs)的日变化样品,分析其中VOCs的浓度特征,运用特征比值和相关性、主成分分析、后向轨迹模型对其来源进行分析,并使用臭氧生成潜势和二次有机气溶胶生成潜势研究了其环境影响.结果表明,观测期间,朔州市VOCs的总体平均浓度为(102.93±35.90)μg·m~(-3),其中芳香烃类浓度最高,为53.52μg·m~(-3);VOCs的日变化呈现了双峰特征,与NO_2和O_3的日变化结合分析显示了其浓度受到了机动车排放和光化学反应的影响显著;源解析结果显示VOCs的排放源主要有机动车排放、汽油和溶剂挥发、燃烧、植物排放等;观测期间气团受北方向、西北方向与西南方向输送的影响;芳香烃类化合物是臭氧生成潜势和二次有机气溶胶生成潜势最高的VOCs类化合物种类.研究结果显示,控制机动车排放和燃烧排放、减低溶剂使用等措施是目前控制朔州市环境空气中VOCs污染的主要途径.     

泰安市大气挥发性有机物污染特征及来源解析

2018年夏季对泰安市城区站点的挥发性有机物(VOCs)进行监测,研究了其污染特征、臭氧生成潜势(OFP)和特征污染物比值,利用PMF源解析模型对VOCs的来源进行了解析.结果 表明,观测期间泰安市VOCs体积分数平均值为(16.57±7.99)× 10-9,VOCs中浓度占比最高的为OVOCs(41.9％),其次为烷...     

广州大气PM_(2.5)中含碳组分的污染特征及来源解析

于2015年1月至11月在广州利用大流量大气颗粒物采样器采集细颗粒物(PM_(2.5))样品,并利用热光反射法(TOR)测定大气颗粒物中有机碳(OC)和元素碳(EC)浓度。结果表明,广州ρ(PM_(2.5))年均值为(69.5±35.6)μg·m~(-3),是GB 3095—2012《环境空气质量标准》中PM_(2.5)年均质量浓度二级标准限值(35μg·m~(-3))的2.0倍,表明广州大气细颗粒物污染严重。OC、EC和总碳气溶胶(TCA)的年均质量浓度分别为(8.31±4.53)、(3.56±2.72)和(16.85±9.60)μg·m~(-3),分别占PM_(2.5)质量浓度的13.2%、5.9%和27.0%,表明含碳组分是PM_(2.5)的重要组成部分。OC和EC浓度季节变化规律存在差异性,OC浓度在冬季最高,而EC浓度在秋季最高。OC和EC的相关性弱和比值高的特征结果表明冬季二次有机碳(SOC)污染最严重,其平均质量浓度为6.9μg·m~(-3),占OC质量浓度的62.4%。主成分分析结果表明,冬季和春季广州PM_(2.5)中碳组分来源较复杂,主要包括机动车尾气、燃煤和生物质燃烧,夏季碳组分的主导污染来源是燃煤和机动车尾气,而秋季碳组分主要来源于机动车尾气。     

北京城区夏冬两季VOCs时间变化和光化学特征的质子转移反应飞行时间质谱(PTR-TOF-MS)观测

为增进对北京地区不同季节大气挥发性有机物(VOCs)变化特征的认识,利用高时间分辨率质子迁移反应-飞行时间质谱(PTR-TOF-MS)于2016年在北京城区开展了VOCs(甲醛、乙醛、丙酮、异戊二烯、苯、甲苯和8碳芳香烃)夏季(6月8日—20日)和冬季(11月22日—12月10日)的连续观测.VOCs体积分数(浓度)的均值为(夏季/冬季,×10~(-9)):甲醛(8.56/24.58)、乙醛(3.95/7.57)、丙酮(5.06/3.50)、异戊二烯(0.66/0.52)、苯(0.53/1.78)、甲苯(1.03/2.54)、8碳芳香烃(1.34/3.42).受大气扩散条件的影响,夏冬两季大部分VOCs浓度波动趋势相近,仅异戊二烯在夏季拥有明显的白天浓度高于夜间的时间序列,其白天的高浓度与植被排放较强有关.由日变化可见:冬季,所有VOCs在中午浓度处于全天较低水平,在早高峰期间VOCs浓度上升明显;夏季,甲醛、乙醛和丙酮等3种含氧VOCs(OVOCs)在中午有短暂的浓度峰值,这与它们光化学二次生成加快有关.由VOC与苯浓度比值的日变化可知:冬季与夏季类似,中午前后3种OVOCs(甲醛、乙醛和丙酮)的光化学生成以及甲苯和8碳芳香烃的光化学消耗都会增强,只是冬季增强的程度明显弱于夏季;在夏冬两季,甲醛中午的光化学生成速率均强于乙醛和丙酮.8碳芳香烃光化学消耗速率大于甲苯的速率仅出现在夏季;异戊二烯在冬季白天不存在植被排放增强的现象,但有光化学消耗加快的特征;夏季北京城区VOCs以机动车排放影响为主,而冬季VOCs还可能来自于燃煤排放.     

制药企业密集区空气中VOCs污染特性及健康风险评价

为研究制药企业密集区产生的挥发性有机物(VOCs)对环境和人群健康的影响,在制药企业密集区周边8个点位采集168个样品,采用预浓缩-GC-MS法测定VOCs的含量,并通过美国环境保护署(US EPA)的健康风险评价模型,对制药企业密集区挥发性有机物(VOCs)污染进行评价.结果表明,制药企业密集区共检测出32种物质,总挥发性有机物(TVOC)浓度为2.04 mg·m-3,芳香烃类和酮类所占比例较高,分别占总VOCs浓度的43%和28%;大部分VOCs浓度是背景值的十倍或百倍.检测到的19种存在健康危害的VOCs不会对人体产生明显的非致癌健康危害;但1,3-丁二烯、氯仿、四氯化碳、苯和1,1,2-三氯乙烷等5种VOCs对人体有致癌健康危害.密集区总VOCs的累积致癌风险指数远超可接受数量级,说明制药企业密集区排放的VOCs对人体以致癌健康危害为主.     

青藏高原东缘冬季PM2.5中碳组分特征和来源解析

于2017年冬季12月13—21日在青藏高原东缘理塘地区分昼夜采集PM_2.5样品,并用DRI2001A热光碳分析仪测定了有机碳(OC)和元素碳(EC)的质量浓度,研究青藏高原PM_2.5中碳组分的化学特征及主要来源,以期为理塘地区制定污染排放政策提供参考。结果表明,2017年冬季青藏高原东缘理塘地区PM_2.5平均质量浓度为44.34μg·m^?3,OC和EC的质量浓度为12.72μg·m^?3和3.85μg·m^?3,分别占PM_2.5质量浓度的29.61%和8.96%。通过经验公式,计算得到总碳气溶胶(TCA)质量浓度为24.20μg·m^?3,占PM_2.5的54.84%,说明碳质气溶胶对青藏高原东缘理塘地区PM_2.5有着十分重要的贡献。OC和EC在白天和夜间都有较高的相关性(相关系数分别为0.74和0.91),表明OC和EC的来源基本一致,受燃烧源影响较大。其中白天的相关系数低于夜间,说明青藏高原东缘理塘地区白天碳组分来源相对复杂。昼夜浓度对比显示,青藏高原东缘理塘地区PM_2.5白天和夜间的质量浓度分别为53.88μg·m^?3和33.44μg·m^?3,OC和EC浓度白天高于夜间,表明白天人为排放相对较高。冬季观测期间,PM_2.5中二次有机碳(SOC)昼夜浓度分别为1.11μg·m^?3和3.03μg·m^?3,分别占OC质量浓度的7.09%、26.59%,表明青藏高原东缘理塘城区白天碳组分主要为一次源。利用PMF 5.0软件对理塘城区碳组分进行进一步的解析,结果显示燃煤和生物质燃烧的混合源对总碳(TC)的贡献高达47.84%,占比最高;其次是汽车尾气和柴油车尾气源,贡献率分别为28.62%和23.54%。     

Characteristics of carbonyls and volatile organic compounds (VOCs) in residences in Beijing,China

Volatile organic compounds (VOCs) and carbonyl compounds were measured both indoors and outdoors in 50 residences of Beijing in heating (December, 2011) and non-heating seasons (April/May, 2012). SUMMA canisters for VOCs and diffusive samplers for carbonyl compounds were deployed for 24 h at each site, and 94 compounds were quantified. Formaldehyde, acetone and acetaldehyde were the most abundant carbonyl compounds both indoors and outdoors with indoor median concentrations being 32.1, 21.7 and 15.3 μg·m⁻³, respectively. Ethane (17.6 μg·m⁻³), toluene (14.4 μg·m⁻³), propane (11.2 μg·m⁻³), ethene (8.40 μg·m⁻³), n-butane (6.87 μg·m⁻³), and benzene (5.95 μg·m⁻³) showed the high median concentrations in indoor air. Dichloromethane, p-dichlorobenzene (p-DCB) and toluene exhibited extremely high levels in some residences, which were related with a number of indoor emission sources. Moreover, isoprene, p-dichlorobenzene and carbonyls showed median indoor/outdoor (I/O) ratios larger than 3, indicating their indoor sources were prevailing. Chlorinated compounds like CFCs were mainly from outdoor sources for their I/O ratios being less than 1. In addition, indoor concentrations between two sampling seasons varied with different compounds. Carbonyl compounds and some chlorinated compounds had higher concentrations in the non-heating season, while alkanes, alkenes, aromatic compounds showed an increase in the heating season. Indoor concentration of VOCs and carbonyls were influenced by locations, interior decorations and indoor activities, however the specific sources for indoor VOCs and carbonyls could not be easily identified. The findings obtained in this study would significantly enhance our understandings on the prevalent and abundant species of VOCs as well as their concentrations and sources in Beijing residences.     

Chemical speciation and anthropogenic sources of ambient volatile organic compounds (VOCs) during summer in Beijing, 2004

Volatile organic compounds (VOCs) were measured at six sites in Beijing in August, 2004. Up to 148 VOC species, including C₃ to C₁₂ alkanes, C₃ to C₁₁ alkenes, C₆ to C₁₂ aromatics, and halogenated hydrocarbons, were quantified. Although the concentrations differed at the sites, the chemical compositions were similar, except for the Tongzhou site where aromatics were significantly high in the air. Based on the source profiles measured from previous studies, the source apportionment of ambient VOCs was preformed by deploying the chemical mass balance (CMB) model. The results show that urban VOCs are predominant from mobile source emissions, which contribute more than 50% of the VOCs (in mass concentrations) to ambient air at most sites. Other important sources are gasoline evaporation, painting, and solvents. The exception is at the Tongzhou site where vehicle exhaust, painting, and solvents have about equal contribution, around 35% of the ambient VOC concentration. As the receptor model is not valid for deriving the sources of reactive species, such as isoprene and 1,3-butadiene, other methodologies need to be further explored.     

垃圾转运站空气中挥发性有机化合物分析

通过对垃圾转运站空气样品进行分析,共检出主要挥发性有机化合物43种。其中国家《恶臭污染物排放标准》控制污染物有4种,它们的含量相对较低,但波动范围较大;USEPA优先控制污染物有5种,虽然种类不多,但检出率较高,因此不应忽视其对环境的影响。     

A review on application of dielectric barrier discharge plasma technology on the abatement of volatile organic compounds

• Applications of non-thermal plasma reactors for reduction of VOCs were reviewed. • Dielectric barrier discharge (DBD) plasma was considered. • Effect of process parameters was studied. • Effect of catalysts and inhibitors were evaluated. Volatile organic compounds (VOCs) released from the waste treatment facilities have become a significant issue because they are not only causing odor nuisance but may also hazard to human health. Non-thermal plasma (NTP) technologies are newly developed methods and became a research trend in recent years regarding the removal of VOCs from the air environment. Due to its unique characteristics, such as bulk homogenized volume, plasma with high reaction efficiency dielectric barrier discharge (DBD) technology is considered one of the most promising techniques of NTP. This paper reviews recent progress of DBD plasma technology for abatement of VOCs. The principle of plasma generation in DBD and its configurations (electrode, discharge gap, dielectric barrier material, etc.) are discussed in details. Based on previously published literature, attention has been paid on the effect of DBD configuration on the removal of VOCs. The removal efficiency of VOCs in DBD reactors is presented too, considering various process parameters such as initial concentration, gas feeding rate, oxygen content and input power. Moreover, using DBD technology, the role of catalysis and inhibitors in VOCs removal are discussed. Finally, a modified configuration of the DBD reactor, i.e. double dielectric barrier discharge (DDBD) for the abatement of VOCs is discussed in details. It was suggested that the DDBD plasma reactor could be used for higher conversion efficiency as well as for avoiding solid residue deposition on the electrode. These depositions can interfere with the performance of the reactor.     

Source apportionment and ozone formation potential of volatile organic compounds in Lagos (Nigeria)

Concentrations of volatile organic compounds (VOCs) of the city air in Oba Akran road, Lagos were investigated. The chlorinated VOCs and xylene in Oba Akran were high. The average benzene/toluene ratio in Oba Akran was 1.7 suggesting that vehicular emission was a possible VOC source in most areas of Oba Akran. The toluene/(m+p-xylene) ratio also suggests a common source of toluene and xylene at these sites, presumably organic solvent used by industries located at Oba Akran. Our results showed that 7.10 tons of CO ₂ equivalents of VOCs are being emitted per year from Oba Akran. Xylenes were found to be the largest contributor to the ozone formation followed by trichloroethylene. A multivariate statistical analysis (Factor analysis extracted with Principal Component Analysis) has been applied to a set of data, and it was found that the main principal components, extracted from the air VOC pollution data, were related to gasoline and oil combustion/industrial activities.     

Characteristics of major volatile organic hazardous air pollutants in the urban air of Kaohsiung city

The concentrations and characteristics of volatile organic hazardous air pollutants (HAPs) in the urban city of Kaohsiung from motor vehicles and dense pollutant sources has become a national concern. To continuously monitor volatile organic HAPs, sampling sites were selected near the four air-quality monitoring stations established by Ethe nvironmental Protection Administration of Taiwan ROC, namely Nan-tz, Tso-ying, San-min and Hsiao-kang, from north to south. An on-site automated online monitor of volatile organic compounds (VOCs) was used for continuous monitoring. This study performed two consecutive days of 24-h monitoring of five volatile organic HAPs form August to October 2005 at the four monitoring sites, which cover the northern, central, and southern areas of Kaohsiung city. The average monitored concentration was 2.78–4.84 ppb for benzene, 5.90–9.66 ppb for toluene, 3.62–5.90 ppb for ethylbenzene, 3.73–5.34 ppb for m,p-xylene, 3.38–4.22 ppb for o-xylene, and 4.48–7.00 ppb for styrene. The average monitored concentrations of the major volatile organic HAPs tended to follow the pattern San-min > Nan-tz > Hsiao-kang > Tso-ying. Among all the species monitored in this study, toluene had the highest ambient concentration, followed by styrene, m,p-xylene, ethylbenzene, o-xylene, and benzene. The results showed that the concentration at night was higher than that in the day for toluene at Nan-tz, San-min, Hsiao-kang, and for benzene at Nan-tz and Hsiao-kang.     

中国北方典型城市空气中苯系物的污染特征

为了研究中国北方典型城市大气中苯系物的污染状况和季节变化特征,于2008年4月—2009年1月间,选取沈阳和天津共11个监测点位分别采集大气样品,并利用三级冷阱预浓缩-GC-MS方法进行分析.结果表明,天津的苯系物污染浓度比沈阳高,这是因为天津的机动车保有量远远大于沈阳,机动车尾气排放量大.苯系物的污染程度与不同季节的气候变化密切关联,两城市均表现为春秋两季污染严重,冬夏两季污染较轻.城市不同功能区采样点的比较和苯与甲苯(B/T)的比值以及各苯系物之间的相关性分析表明,两城市苯系物污染浓度均受到局部排放源的明显影响,但在大部分地区交通源仍为主要排放源.     

天津市环境空气中铅（Pb）的污染

本文统计分析了１９９４￣１９９６年天津市环境空气及交通环境中铅的浓度值，分析了天津市环境空气及交通环境中锅污染的程度、变化趋势、污染来源。由此说明天津市出现“尾气型”污染的迹象。为此，务必加大力度对机动车尾气排放的监测和管理，这对降低污染，改善天津市环境空气质量具有一定的现实意义。     

Target the neglected VOCs emission from iron and steel industry in China for air quality improvement

● Haze formation in China is highly correlated with iron and steel industry. ● VOCs generated in sinter process were neglected under current emission standard. ● Co-elimination removal of sinter flue gas complex pollutants are timely needed. Recent years have witnessed significant improvement in China’s air quality. Strict environmental protection measures have led to significant decreases in sulfur dioxide (SO₂), nitrogen oxides (NO_x), and particulate matter (PM) emissions since 2013. But there is no denying that the air quality in 135 cities is inferior to reaching the Ambient Air Quality Standards (GB 3095–2012) in 2020. In terms of temporal, geographic, and historical aspects, we have analyzed the potential connections between China’s air quality and the iron and steel industry. The non-target volatile organic compounds (VOCs) emissions from iron and steel industry, especially from the iron ore sinter process, may be an underappreciated index imposing a negative effect on the surrounding areas of China. Therefore, we appeal the authorities to pay more attention on VOCs emission from the iron and steel industry and establish new environmental standards. And different iron steel flue gas pollutants will be eliminated concurrently with the promotion and application of new technology.