西南某化工园区周边区域环境空气中苯系物和卤代烃的污染特征及健康风险研究

于2020年8月和11月,在中国西南某化工园区周边6个采样点采集环境空气样品,对5种典型苯系物(苯、甲苯、乙苯、邻二甲苯、间/对二甲苯)和7种典型卤代烃(三氯甲烷、三氯乙烯、四氯化碳、四氯乙烯、三溴甲烷、一溴二氯甲烷和二溴一氯甲烷)进行研究,明确了区域典型苯系物和卤代烃(BSHs)的污染特征,并评估其对人体的健康风险。结果表明:化工园区周边环境空气中苯系物检出率均 60%,卤代烃中除三溴甲烷、一溴二氯甲烷和二溴一氯甲烷外,检出率均 50%。苯系物和卤代烃的平均质量浓度分别为4.14～11.19μg/m~3和0.30～10.86μg/m~3。BSHs的浓度夏季低于冬季,这可能与人为的季节性燃烧源有关。苯、四氯化碳和四氯乙烯超过国际WELL建筑标准v2,全年超标率分别为3.33%,8.33%和11.67%。BSHs的非致癌和致癌风险均为成人儿童,成人和儿童的非致癌总风险分别为1.87×10~(-2)和1.26×10~(-2),处于可接受水平;成人和儿童的致癌风险分别为1.76×10~(-3)和1.19×10~(-3),处于不可接受水平。     

化工企业废气BTEX排放及周边居民区空气暴露健康风险分析

采用气相色谱-质谱法,于2016年9月和12月对江苏省某化工企业与苯系物排放相关的废气排放口和周边居民区环境空气中苯、甲苯、邻二甲苯、间/对二甲苯、乙苯等5种典型苯系物（BTEX）的排放和区域污染特征进行分析,并开展BTEX来源分析及人体健康风险评估研究。结果表明,化工企业有机废气排放口苯质量浓度最高,超过《化学工业挥发性有机物排放标准》（DB32/3151—2016）限值,超标率达26.4%;环境空气中BTEX平均质量浓度为47.31μg/m³,BTEX检出率均超过80%,秋季和冬季BTEX质量浓度分别为72.5和22.2μg/m³,各组分质量浓度大小排序为：苯＞甲苯＞乙苯＞间/对-二甲苯＞邻-二甲苯,与废气排放口浓度大小顺序一致;与其他城市和地区进行比较,BTEX质量浓度处于中等水平。比值分析法研究BTEX来源结果表明,本地排放源是化工企业周边环境空气BTEX主要来源,一定程度上也受交通排放、化石燃料燃烧等污染源的影响。人体健康风险评估结果表明,BTEX单组分非致癌风险值（HQ）在安全范围之内,各监测点位 BTEX的HQ均＜１,非致癌风险可以忽略不计;苯的致癌风险值（R）为7.33×10^-6～7.49×10^-5,均超过10,有一定的致癌风险,且苯是I类致癌物质,应采取源头控制措施避免健康风险。     

某大型化工企业周边居民区积尘中多环芳烃调查及健康风险评价

以江苏省某大型化工企业周边居民区为研究区域,调查企业主导风的下风向2 km范围内的居民区以及对照区积尘中多环芳烃(PAHs)含量,对16种PAHs污染分布和特征进行研究,并评估积尘PAHs通过暴露途径对人群健康风险。结果表明:居民区积尘中16种PAHs全部检出,污染区∑PAHs均值为2 294μg/kg,明显高于对照区145μg/kg;污染区7个测点中有6个测点苯并(a)芘出现超标,超标倍数为0. 17～2. 5倍;所测的16种PAHs化合物中蒽、荧蒽、芘、、苯并(b)荧蒽、苯并(k)荧蒽、苯并(a)芘浓度相对较高;通过PAHs主成分分析和特征比值判断,不完全燃烧源对积尘中PAHs贡献率达77. 4%,污染区PAHs来源呈现石油燃烧、煤燃烧以及石油源的复合污染特征,对照区PAHs主要来源为煤的不完全燃烧;以苯并(a)芘毒性等效浓度进行风险评估,污染区致癌风险值明显高于对照区,儿童摄入PAHs风险总体高于成人;对照区儿童和成人致癌风险均小于1×10~(-6),不存在致癌风险;污染区儿童和成人平均致癌风险值分别为3. 95×10~(-6)、2. 65×10~(-6),在可接受范围内,但存在潜在致癌风险。     

家具制造企业密集区空气中VOCs污染状况及健康风险评价

采用Tenax管吸附-热脱附-气相色谱法测定家具制造企业密集区空气中挥发性有机物(VOCs),并应用美国国家环保局(USEPA)的健康风险评价模型评估其对周边人群的影响。结果表明,家具制造企业密集区总VOCs的质量浓度为0.931 mg/m3,11种目标物中乙酸乙酯、丙酮和乙酸丁酯所占比例较高,分别占总VOCs的20.2%、10.7%和9.1%。该区总VOCs的累积非致癌风险指数为3.47×10-7,低于1,不会对人体产生明显的非致癌健康危害;其累积致癌风险指数为2.49×10-5,是可接受致癌风险值(1.0×10-6)的25倍,可能对人群存在致癌影响。     

泰州市夏季大气典型VOCs污染特征及健康风险评估

于2019年8—9月,采用大气预浓缩-气相色谱质谱联用仪(GC-MS)对泰州市3个监测点位环境空气中57种挥发性有机物(VOCs)进行分析,并开展了VOCs组成特征、臭氧生成潜势(OFP)、VOCs来源及健康风险评价研究。结果表明:3个点位环境空气中φ(VOCs)范围为1.3×10^(-9)~46.9×10^(-9),平均值为8.5×10^(-9)。烷烃在VOCs中所占比例最大。各点位φ(VOCs)平均值依次为:工业园区>公园路>天德湖公园。公园路点位VOCs中苯系物受汽车尾气排放影响较大,天德湖公园和工业园区点位除了受汽车尾气排放影响,还受到有机溶剂和涂料的挥发影响,主要受本地污染主导。OFP中贡献最大的物质为乙烯,OFP值为5.5μg/m^(3),其次为烷烃。健康风险评价结果显示,各点位VOCs非致癌类风险均较低,处于安全范围内。各点位夏季环境空气中苯对人体均具有一定致癌风险。     

江苏某县乡镇饮用水中挥发性有机物的检测及其风险评价

在江苏某癌症高发县5个乡镇10个村进行布点取样,采集深层地下水与浅层地下水共计20个水样。采用吹扫捕集与气相色谱-质谱联用方法测定水样中14种挥发性有机物(VOCs),检出二氯甲烷、1,3-二氯丙烷、三氯甲烷、苯和四氯化碳5种VOCs,其质量浓度分别为0.14～1.71、ND～50.98、0.29～90.02、0.09～2.35、0.18～3.45μg/L。2个水样中的三氯甲烷和6个水样中四氯化碳超过《生活饮用水卫生标准》(GB 5749—2006)规定的限值。采用优化的美国环保局风险评价模型进行人体健康风险评价,其非致癌风险指数为0.000 7～0.072,致癌风险水平1.70×10-7～2.03×10-5,70%水样的致癌风险水平超过10-6水质监控值,2个浅层地下水的致癌风险水平较高。四氯化碳和三氯甲烷对非致癌风险指数和致癌风险水平贡献较大。     

南宁市河流型水源地重金属污染调查与健康风险评价

通过对南宁市河流型水源地水体中Pb、Cd、Hg、As浓度调查与健康风险评价研究,结果表明:这4种元素在水体中的质量浓度较低,均达到《地表水环境质量标准》(GB 3838-2002)Ⅱ类标准;经饮水途径引起的健康风险从大到小依次为AsCdPbHg,说明As是南宁市饮用水源中的主要风险因子;4种元素通过饮水途径引起的平均个人年健康致癌风险值为1.48×10-6a-1~13.75×10-6a-1,非致癌风险值为7.05×10-10a-1,均低于美国环保局和国际辐射防护委员会的推荐值。     

下辽河平原地下水健康风险评价

通过在下辽河平原布设217个地下水采样点,调查监测其中典型的无机、有机化合物,并应用美国EPA健康风险评价模型进行风险评价。结果表明:该区域地下水中无机化合物较有机化合物浓度水平高;无机化合物中NO_3~-、NO_2~-、Mn及As浓度较高,有机化合物中γ-六六六浓度较高。所有监测的无机、有机化合物通过饮用水途径引起的致癌风险高于非致癌风险;所有化合物的非致癌风险数值均小于ICRP推荐的最大可接受风险水平10~(-6)a~(-1),As致癌风险最大值为6.15×10~(-5)a~(-1),超过EPA推荐的可接受值5.0×10~(-5)a~(-1)。     

北京市机动车尾气排放PM10组分特征研究

为提高机动车尾气排放可吸入颗粒物PM10成分谱的代表性和准确性,提出并采用在机动车尾气检测线上采用稀释通道采样器随机采集机动车排出PM10的采样方法。采集了591辆轻、重型汽油车和柴油车尾气排放PM10,测试并分析了颗粒物的27种组分。数据表明:机动车排放颗粒物PM10中含量丰富的组分为OC、EC、NH+4、NO-3和SO2-4;柴油车排放PM10中OC和EC的质量分数为49.08%,是汽油车(38.38%)的1.3倍,汽油车的OC/EC(2.36)是柴油车(0.78)的3倍;汽油车排放PM10中的二次转化产物(SO42-+NH4++NO3-)的质量分数为19.37%,是柴油车(3.57%)的5.4倍;汽油车排放NH+4是柴油车的5.3倍。     

南方某河流型饮用水源地重金属健康风险评估

对南方某河流型饮用水源地水中重金属含量进行调查研究,并应用美国环保局推荐的健康风险评价模型对其进行健康风险评价。结果表明,该饮用水源地水中重金属类污染物健康风险值相对较低,其中重金属类致癌污染物的健康风险均值大小顺序为CrAsCd,其值分别为8.19×10-6、2.11×10-6、1.59×10-7a-1,Cr、As的风险值高于瑞典、荷兰、英国推荐的最大可接受水平(1×10-6a-1),而低于国际(ICRP)与美国环保局的健康风险可接受水平(5×10-5a-1和1×10-4a-1),成为该饮用水源地的主要致癌污染因子。重金属类非致癌污染物的健康风险均值大小顺序为CuNiZn,其值分别为1.95×10-10、1.19×10-10、5.73×10-12a-1,均远远低于致癌污染物的健康风险值。     

乌鲁木齐市2种主要温室气体浓度水平

利用2010年乌鲁木齐市近地面大气主要温室气体的自动监测数据,分析了CO2和CH4浓度的分布特征和时间变化规律.结果表明,乌鲁木齐市CO2小时浓度在(349.1～605.0)×10-6之间;采暖期浓度高,平均浓度为438.1 ×10-6,非采暖期浓度低,平均浓度为375.0×10-6.CH4浓度日变化明显,昼间低、夜间...     

In-vehicle Measurement of Ultrafine Particles on Compressed Natural Gas, Conventional Diesel, and Oxidation-catalyst Diesel Heavy-duty Transit Buses

Many metropolitan transit authorities are considering upgrading transit bus fleets to decrease ambient criteria pollutant levels. Advancements in engine and fuel technology have lead to a generation of lower-emission buses in a variety of fuel types. Dynamometer tests show substantial reductions in particulate mass emissions for younger buses (<10 years) over older models, but particle number reduction has not been verified in the research. Recent studies suggest that particle number is a more important factor than particle mass in determining health effects. In-vehicle particle number concentration measurements on conventional diesel, oxidation-catalyst diesel and compressed natural gas transit buses are compared to estimate relative in-vehicle particulate exposures. Two primary consistencies are observed from the data: the CNG buses have average particle count concentrations near the average concentrations for the oxidation-catalyst diesel buses, and the conventional diesel buses have average particle count concentrations approximately three to four times greater than the CNG buses. Particle number concentrations are also noticeably affected by bus idling behavior and ventilation options, such as, window position and air conditioning.     

扩散采样法测定室内空气中的BTEX

建立了扩散吸附管采样,热脱附仪和气相色谱联用测定室内空气中BTEX的监测分析方法,方法的最低检出限为0.0002mg/m3。该方法使用方便、便于携带、无需电源,且与传统的泵采样方法具有较好的可比性,适合于室内空气中BTEX的监测。     

Distribution and health-risk of polycyclic aromatic hydrocarbons in soils at a coking plant

Nineteen soil samples were collected in and around Songshan coking plant in Guangdong province of China and analyzed for eighteen polycyclic aromatic hydrocarbons (PAHs) by gas chromatography-mass spectrometry (GC-MS). The total concentration of PAHs ranged from 2.36 to 1146.39 mg kg(-1) dry weight, varying significantly among the sampling sites, most individual PAHs were correlated with each other. A cluster analysis was performed to examine the correlation of PAH distribution, five groups were observed with sample types in the coking plant. 2-3 ring PAHs were predominant in group I and II, while 4-5 ring PAHs showed great abundance in group III, IV and V, which contributed to the distance from the emission sources in the coking plant and the behaviors of particle-bound and gaseous PAHs. The ratios of Flu?:?(Flu + Pyr), BaA?:?(BaA + Chr), InP?:?(InP + BgP) and Ant?:?(Ant + Phen) ratios were 0.51-0.87, 0.16-0.89, 0.47-0.68 and 0.03-0.60, respectively. The total index of all studied soils was > 6, indicating that the source of the PAHs in coking plant soils were from the pyrolysis processes. Health risk assessments were carried out by dermal PAH exposure data to quantify cancer risk. The resultant lifetime exposure levels due to TEQ(BaP) desorbed onto skin for workers ranged from 2.25 × 10(-7) to 7.86 × 10(-5) mg kg(-1) per day, and the estimated cancer risks were between 8.45 × 10(-6) and 2.94 × 10(-3), indicating that the dermal exposures of PAHs to coking workers might be acceptable in most soil sites.     

预冷冻浓缩系统与气相色谱-质谱法测定空气中苯的测量不确定度评定

根据 Top－down技术中的控制图法，运用预冷冻浓缩系统与气相色谱－质谱联用对苯标准样气进行多次测定。通过计算和评定，得出当苯的测定浓度为100×10^－9时，不确定度为5．1×10^－9。     

Application of portable gas chromatography-photo ionization detector combined with headspace sampling for field analysis of benzene, toluene, ethylbenzene, and xylene in soils

A method based on headspace (HS) sampling coupling with portable gas chromatography (GC) with photo ionization detector (PID) was developed for rapid determination of benzene, toluene, ethylbenzene, and xylenes (BTEX) in soils. Optimal conditions for HS gas sampling procedure were determined, and the influence of soil organic matter on the recovery of BTEX from soil was investigated using five representative Chinese soils. The results showed that the HS-portable-GC-PID method could be effectively operated at ambient temperature, and the addition of 15 ml of saturated NaCl solution in a 40-ml sampling vial and 60 s of shaking time for sample solution were optimum for the HS gas sampling procedure. The recoveries of each BTEX in soils ranged from 87.2 to 105.1 %, with relative standard deviations varying from 5.3 to 7.8 %. Good linearity was obtained for all BTEX compounds, and the detection limits were in the 0.1 to 0.8 μg kg^?1 range. Soil organic matter was identified as one of the principal elements that affect the HS gas sampling of BTEX in soils. The HS-portable-GC-PID method was successfully applied for field determination of benzene and toluene in soils of a former chemical plant in Jilin City, northeast China. Considering its satisfactory repeatability and reproducibility and particular suitability to be operated in ambient environment, HS sampling coupling with portable GC-PID is, therefore, recommended to be a suitable screening tool for rapid on-site determination of BTEX in soils.     

上海城区交通干道苯系物污染初探

利用设置在上海市中心城区交通主干道旁的路边空气质量自动监测站2018年1—12月的连续观测数据,研究苯系物(BTEX)污染水平、变化特征以及其与CO、NO x和气象参数的关系。结果表明,观测期间BTEX小时均值为0.10~169.38μg/m^3,年均值为(13.66±0.14)μg/m^3,甲苯占比最高。ρ(BTEX)受污染源排放强度和天气状况的影响大,其日变化呈单谷型,冬季值比夏季高。BTEX各化合物具有较好的同源性,ρ(苯)/ρ(甲苯)为(0.49±0.01)。BTEX与机动车尾气主要成分CO、NOx呈正相关,与风速负相关。其值低于北京、南京、郑州、杭州和西安等城市。     

Multivariate statistical study of seasonal variation of BTEX in the surface water of Savitri River

Volatile organic compounds (VOCs) analysis was carried out for the surface water of the Savitri river during the period of June 2005 to June 2007. BTEX compounds (Benzene, Toluene, Xylene & Ethyl benzene) were analyzed by using micro extraction technique (Purge & Trap). Concentrations of these BTEX compounds were ranging from 0.1 to 1.5 ppm during sampling period. Higher concentrations of BTEX were found at sampling location VI. Concentration of ethyl benzene was very low as compare to other compounds. However, the concentration of benzene was very high. Seasonal variations in conc. of BTEX compounds were observed and higher concentration was detected during the summer season. Salting-out effect had given higher quantification values. In PCA and PFA, the component loading for all the variables are positively correlated. Death of fishes was observed in the river that is indication of severe pollution problem.     

便携式质谱仪应用于交通干线苯系物污染特征分析

介绍了EcoSys-P便携式质谱仪在无车日前后对交通干线环境空气中苯系物现场监测中的情况,同时该方法与经典的气相-质谱联机进行了对比试验,相对偏差≤25%,能够满足交通干线环境空气苯系物的现场监测要求.     

Atmospheric BTEX concentrations in the vicinity of the crude oil refinery of the Baltic region

Among chemical industries, petroleum refineries have been identified as large emitters of a wide variety of pollutants. Benzene, toluene, ethylbenzene, and xylene (BTEX) form an important group of aromatic volatile organic compounds (VOCs) because of their role in the troposphere chemistry and the risk posed to human health. A very large crude oil refinery of the Baltic States (200,000 bbl/day) is situated in the northern, rural part of Lithuania, 10 km from the town of Ma?eikiai (Lithuania). The objectives of this study were: (1) to determine of atmospheric levels of BTEX in the region rural and urban parts at the vicinity of the crude oil refinery; and (2) to investigate the effect of meteorological parameters (wind speed, wind direction, temperature, pressure, humidity) on the concentrations measured. The averaged concentration of benzene varied from 2.12 ppbv in the rural areas to 2.75 ppbv in the urban areas where the traffic was determined to be a dominant source of BTEX emissions. Our study showed that concentration of benzene, as strictly regulated air pollutant by EU Directive 2008/50/EC, did not exceed the limit of 5 ppbv in the region in the vicinity of the crude oil refinery during the investigated period. No significant change in air quality in the vicinity of the oil refinery was discovered, however, an impact of the industry on the background air quality was detected. The T/B ratio (0.50-0.81) that was much lower than 2.0, identified other sources of pollution than traffic.