北京市大气颗粒物中多环芳烃的分布特征

用撞击式分级采样器同步采集了北京市城乡结合部、郊区的2003年4个季节的不同粒径大气颗粒物样品,用气相色谱-质谱分析了其中的多环芳烃,并对两个地区大气颗粒物中的多环片烃含量、分布及季节性变化特征进行了探讨。     

大气颗粒物中多环芳烃的粒径分布

用GC/MS法测定了北京市北部的城乡结合部和远郊区的大气颗粒物中的16种优控多环芳烃(PAHs)的浓度。采样时间从2003年1月到11月,分季节采样。采样器采集的大气颗粒物粒径分为5段,粒径范围从小于等于1.1μm到100μm。对颗粒物中的总优控PAHs和检测出的单一优控PAHs在不同地区、不同时期的粒径分布进行了比较和讨论。总优控PAHs和单一优控PAHs化合物均趋向于吸附在小粒径颗粒物中,占总量47%~65%的总优控PAHs分布在粒径小于1.1μm的颗粒物中,只有不到10%的总优控PAHs分布在粒径大于7.0μm的粗颗粒物上。     

大气中多环芳烃衍生物的研究进展

多环芳烃衍生物是一类已被证实比多环芳烃具有更强"三致作用"(致癌、致畸和致基因突变)的环境污染物,它广泛存在于环境介质特别是大气颗粒物中。本文就其来源、分布、采样方式、样品前处理、分离分析方法等方面综述了近年来大气颗粒物中多环芳烃衍生物的的研究进展。     

大气气溶胶中多环芳烃的紫外光降解研究

以大容量空气总悬浮微粒采样器采集了大气气溶胶样品,以石英滤膜为载体,研究了气溶胶中的多环芳烃（ＰＡＨｓ）在紫外光照条件下的光降解规律,气溶胶中的多环芳烃在紫外光照下发生迅速的降解,其光降解反应为一级反应,光降解速率常数与它们的极谱氧化半波电位及化合物结构有关而与降解温度关系不明显。     

大气中多环芳烃的分布特征研究进展

大气中PAHs的分布特征主要表现为时空分布不同。不同的地区间浓度不同,重工业城市大气中PAHs浓度明显高于轻工业城市,近年来我国大气环境质量明显好转,地区间PAHs污染浓度差异缩小;不同环数PAHs在气固两相以及在不同粒径颗粒物中分布不同,低环数PAHs主要分布在气相中和大粒径的颗粒物中,高环数PAHs主要分布于固相中和小粒径的颗粒物中;不同季节大气中PAHs的浓度不同,北方地区采暖期高于非采暖期,南方地区冬季气态PAHs浓度夏季高于冬季,颗粒物中PAHs浓度冬季>秋季>春季>夏季;室内PAHs浓度高于室外,不同场所空气中PAHs浓度不同。     

大气颗粒物中多环芳烃物质检测方法优化研究

在探讨不同体系多环芳烃测试方法的基础上,为着重优化大气颗粒物中多环芳烃物质的超声—GC-MS检测分析方法,设置A、B、C、D、E 5组不同萃取剂与超声时间的前处理方法(A=V(二氯甲烷)∶V(丙酮)=1∶1(45 min),B=V(二氯甲烷)∶V(甲醇)=2∶1(45 min),C=正己烷(60 min),D=正己烷(30 min),E=V(丙酮)∶V(正己烷)=1∶1(60 min)),处理后的样品利用GC-MS进行测试,结果表明,E组的平均回收率为67.27%～128.59%,相对偏差为0.40%～8.87%,方法最优。同时采用E组方法对2017年10月25日—11月30日(采暖期)和2018年3月19日—4月30日(非采暖期)总悬浮颗粒物(TSP)中16种多环芳烃的含量进行检测分析,得到采暖期和非采暖期含量分别为1.463 0×10~(-3)μg/mL和1.095 1×10~(-3)μg/mL,均未超过标准(GB 3095—2012)限值,采暖期与非采暖期中16种多环芳烃中BaP对总等效质量浓度(TEQ)的贡献值最大分别为5.61×10~(-5)μg/mL(占45.90%)、2.75×10~(-5)μg/mL(占34.55%),其次是BbF贡献值分别为2.61×10~(-5)μg/mL(占21.36%)、1.94×10~(-5)μg/mL(占24.40%),表明BaP和BbF是评价长春市TSP中多环芳烃健康风险的重要组分。     

餐饮油烟中多环芳烃排放特征分析

以餐饮油烟为研究对象,分析油烟中多环芳烃污染物的排放特征。本实验采用外标法定性定量,所用仪器为高效液相色谱。分别从油烟温度、食用油种类、油烟污染形态3方面分析排放特征。结果表明：温度与多环芳烃排放成正比关系,当温度为200℃时,PAHs中蒽组分排放质量浓度最高,达374.59μg·m^-3;不同食用油的PAHs平均排放质量浓度由高到低顺序为：豆油、菜籽油、花生油、猪油。豆油烹饪时产生组分蒽最高可达到276.88μg·m^-3;油烟颗粒物污染和油烟气态污染物排放多环芳烃成分及变化特征相似,气体污染物排放的PAHs平均质量浓度高于颗粒污染物排放PAHs质量浓度。     

民用燃煤颗粒物及多环芳烃排放特性

民用煤的不完全燃烧是大气中颗粒物及其多环芳烃的主要排放源之一,对大气环境和人体健康均造成了严重危害。为了评价不同“煤炉匹配”方式对16种优先控制的高毒性多环芳烃（PAHs）排放的影响,研究了烟煤块煤、烟煤型煤、无烟煤型煤和兰炭4种不同燃料在代表性的3种民用炉具（正烧炉、反烧炉和解耦燃烧炉）中的颗粒物（PM）及其PAHs的排放特性。根据实验结果进一步计算了毒性当量,并与有关文献报道数据进行了对比。在解耦燃烧炉中,烟煤型煤PM和PAHs的排放因子（EF_PM 和EF_PAHs）（0.50 g/kg、403.2 μg/kg）分别是烟煤块煤（3.65 g/kg、989.6 μg/kg）、兰炭（1.08 g/kg、622.3 μg/kg）、无烟煤型煤（2.10 g/kg、148.3 μg/kg）的13.7%、46.3%、23.8%和42.3%、67.3%、282.3%,除了EF_PAHs高于无烟煤型煤之外,EF_PM 和EF_PAHs均明显低于其他煤种;以烟煤块煤为原料,在解耦炉中燃烧的EF_PM 和EF_PAHs（3.65 g/kg、989.6 μg/kg）分别是正烧炉（46.58 g/kg,16182.3 μg/kg）和反烧炉（6.00 g/kg,11749.4 μg/kg）的7.8%、60.8%和6.1%、8.4%,说明炉具燃烧形式对EF_PM和EF_PAHs的影响大于燃料种类;三种“煤炉匹配“方式（解耦炉+烟煤型煤、正烧炉+兰炭、正烧炉+无烟煤型煤）的EF_PM和EF_PAHs（0.50 g/kg、1.62 g/kg、1.32 g/kg和403.2 μg/kg、1196.5 μg/kg、66.5 μg/kg）均低于传统正烧炉+烟煤块煤（46.58 g/kg,16182.3 μg/kg）以及近年来大部分文献报道的数据（0.68~24.3 g/kg,680~137700 μg/kg）。结果表明,炉具燃烧形式和煤质特性均是影响EF_PM和EF_PAHs的主要因素,但高效的燃烧方式能够大幅降低煤质特性对污染物排放造成的影响,通过对炉具的不断改进以及采用合适的“煤炉匹配”技术,能够对我国储量巨大的烟煤资源合理、有效和清洁地利用。     

大气中的多环芳烃综述

多环芳烃是指一类含有超过两个苯基的化合物,包含蒽和菲等150多种不同性质的化合物.其英文全称为polycyclic aromatic hydrocarbon,简称PAHs.综述了多环芳烃的来源和危害,以及多环芳烃的提取和检测方法.     

河流沉积物中多环芳烃(PAHs)类化合物提取技术的比较研究

河流沉积物中的多环芳烃(PHAs)威胁着河流底栖生物以及人类的健康,不断发展的检测技术可以帮助人类更好地研究PAHs类污染物的沉积、迁移、转化规律。文章综述了河流沉积物中PHAs的前处理提取技术,对索氏提取、自动索氏提取、固液搅拌萃取、UAE、MAE、SFE、ASE和吹扫捕集法等提取方法的提取条件、成本和效率进行了比较。     

Removal of Poly Aromatic Hydrocarbons (PAHs) from Water: Effect of Nano and Modified Nano-clays as a Flocculation Aid and Adsorbent in Coagulation-flocculation Process

Water treatment process involving simultaneous action of adsorption on different nano and organo-modified nano-clays followed by coagulation-flocculation by alum and poly aluminium chloride (PAC) has been evaluated for the removal of PAHs (naphthalene, acenaphthalene, phenanthrene, fluoranthene, anthracene, and pyrene) from water. When clay minerals along with alum and PAC were used for treatment, 37.4–100.0% removal of PAHs was observed compared to 20–38% removal using normal water treatment process with either alum or alum + PAC. The effectiveness of clay minerals for removal of PAHs followed the order (P < 0.05): halloysitenano-clay (HN-clay) < normal bentonite (NB-clay) < hydrophilic nano-bentonite (HNB-clay) < nano-montmorillonite modified with dimethyl dialkyl amine (DMDA-M-clay) ≈ nano-montmorillonite modified with octadecylamine and aminopropyltriethoxysilane (ODAAPS-M-clay) ≈ nano-montmorillonite modified with octadecylamine (ODA-M-clay) in combination with alum + PAC. The modified treatment process (alum + PAC + clay minerals), where water was initially treated with clays followed by normal process of coagulation (alum + PAC), was found to be the most effective method with maximum removal for ODAAPS-M-clay (97.7–100.0%) which is at par wih ODA-M (97.0–100.0%), and DMDA-M-clay (94.8–100%). The removal of PAHs varied in the order: naphthalene ≈ acenaphthalene > anthracene ≈ pyrene > phenanthrene > fluoranthrene. The treatment combination having the maximum removal capacity was also used eficiently for the removal of PAHs from natural and fortified natural water. This article demonstrated adsorption-coagulation integrated system has the potential to remediate PAHs polluted water.     

海洋中多环芳烃生物降解与修复研究进展

在人为活动和自然活动的影响下,海洋中多环芳烃(PAHs)的污染急剧加重,引起了广泛的关注。在简要介绍PAHs的特点、来源、分布以及海洋中PAHs污染的基础上,论述了海洋中PAHs微生物降解的最新研究进展,阐述了PAHs生物降解的途径和机制,归纳了微生物修复技术在海洋PAHs污染治理方面的应用以及红树林在去除PAHs中所发挥的作用,最后对海洋中PAHs的生物降解与修复技术发展前景进行了展望。     

Particle Associated Polycyclic Aromatic Hydrocarbons (PAHS) in Urban Air of Agra

Total Suspended Particulate Matter (TSPM) samples were collected at Nunhai Agra from April to September 2006. The concentrations of 16 PAHs in aerosols were quantified. The dominated predominant PAHs in TSPM include high molecular weight (HMW) congeners BghiP, DbA, IP and BaP. Nap and Acy were not detected in any of the samples. The sum of 14 priority PAHs ranged from 150 to 480 ng m^?3 with a mean value of 269 ± 121 ng m^?3. The Results indicated that PAH concentrations at Nunhai were higher than in other industrial sites, but are comparable to those measured in several urban Chinese cities, however, and less than the industrial locations of China. Higher HMW PAH concentration were attributable to higher rates of emissions as well as or greater scavenging and adsorption of vapor phase PAH on available TSPM. Potential sources of PAHs in aerosols were identified using the diagnostic ratios between PAHs. Vehicular emissions were the main contributors of particulate-associated PAHs, with minor contribution from stationary combustion sources may also contribute to the particulate PAHs. PAHs in aerosols were predominantly from gasoline and diesel engines.     

Concentrations and Source Identification of Polycyclic Aromatic Hydrocarbons (PAHs) in Mangrove Sediments from North of Persian Gulf

The concentrations of 16 Environmental Protection Agency (EPA) priority polyaromatic hydrocarbons (PAHs) were quantified in surface sediments from Hormozgan Province mangroves, south of Iran in dry and wet seasons. Sampling stations were selected in Laft and Khamir mangroves with international importance. Polyaromatic hydrocarbons varied from 75.24 ± 11.24 to 581.94 ± 637.39 ng/g dry weight basis. Pollution sources and their contribution for polyaromatic hydrocarbons pollution in sediments of Hormozgan mangroves were appointed based on molecular ratios and statistical methods, including principal components analysis (PCA) and multiple linear regression/principal components analysis (PCA/MLR) tests. Both of pyrogenic and petrogenic sources contributed in detected concentrations of PAHs. Contribution percentages of pyrogenic and petrogenic origins were estimated at 73.20 and 26.79%, respectively. Temporal variations showed that sediments contained higher levels of ∑PAHs in wet season than dry time. However, the mean detected ∑PAHs was lower than international quality guidelines; the high concentration of PAHs was found in Laft mangrove, suggesting the presence of PAH polluted localized area.     

Effect of Gamma Irradiation on Some Carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) in Wheat Grains

Gamma irradiation effects on seven carcinogenic polycyclic aromatic hydrocarbons (PAHs) were investigated. 0, 1, 5, 10, and 15 kGy of gamma irradiation doses were used in wheat grain treatments. PAHs were extracted and their concentrations at each doses were determined using HPLC equipped with fluorescence analysis. Results demonstrate a reverse relationship between PAHs concentrations and gamma irradiation doses. PAHs concentrations decreased when the gamma irradiation dose increased. The total of PAHs concentration decreased by 35% at 1 kGy while the reduction exceeded 70% for doses higher than 5 kGy. PAHs reduction in irradiated grain samples versus irradiation dose was linear/exponential depending on the structure of PAHs compounds. Results could be of great importance when gamma irradiation is used for the elimination of PAHs from wheat grains.     

The Spatial and Temporal Variations of Polycyclic Aromatic Hydrocarbons (PAHs) in Environmental Matrices in the Czech Republic

The paper is a review of the PAH emission inventories and the results of ambient air measurements of PAHs on regional a local level and determination of PAHs in other abiotic and biotic samples in the Czech Republic (CR). The main sources of polycyclic aromatic hydrocarbons (PAHs) in the country are associated with electric and thermal energy production, waste incineration, road traffic and some industrial processes (e. g. high-temperature coal carbonation, catalytic cracking of crude oil and aluminium production).     

改进索氏提取器提取土壤中多环芳烃（菲、蒽、屈）

文章用改进索氏提取器与自动索氏提取器提取土壤中加标多环芳烃（菲、蒽、屈）,采用高效液相色谱法对提取液进行分离测定,并选择了流动相最佳比例。结果表明,采用改进索氏提取器,二氯甲烷作提取剂,氧化铝柱层析法纯化,并用HPLC—UVD测定可得到很好的效果。三种多环芳烃的平均加标回收率在78.7%~111%之间,且重现性较好。     

Thermodynamic Behavior of Stable Carbon Isotopic Compositions of Individual Polycyclic Aromatic Hydrocarbons Derived from Automobiles

Concentrations, molecular compositions, and compound-specific stable carbon isotopic compositions ( i 13 C) of polycyclic aromatic hydrocarbons (PAHs) in gasoline exhaust particles (GEPs) and diesel exhaust particles (DEPs) were investigated in this study. i 13 C of PAHs in GEPs ranged from m 13.3 to m 26.8, and that in DEPs ranged from m 21.7 to m 26.3. The interspecies i 13 C variations in each sample were 5.3 - 2.2 in GEPs and 2.6 - 1.3 in DEPs. PAHs in GEPs show larger interspecies i 13 C variation than those in DEPs; hence, a degree of carbon isotopic fractionation during the conversion from fuel to PAH seems to be larger in gasoline engines than that in diesel engines. Pyrene series PAHs, which consist of only hexagonal rings, in almost all GEP samples show strong negative correlation between the H/C ratio and i 13 C whereas fluoranthene series PAHs, which contain a pentagonal ring, show less systematic isotopic behavior in GEP samples. A kinetic isotope effect in thermal cracking of organic macromolecules may be minor for PAH formation in vehicle engines. We suggest that the isotopic trend of pyrene series in GEPs can be explained by a thermodynamic isotope effect, and that disturbance from isotopic equilibrium may cause a weak correlation between the isotopic behavior and the H/C ratio among the interspecies PAHs.