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1.
沉积物是多环芳烃(polycyclic aromatic hydrocarbons,PAHs)在环境中迁移归趋的一个重要的汇[1]。沉积物中多环芳烃的提取方法主要有索氏提取、超声波提取、微波萃取、加速溶剂提取及超临界流体萃取等。其中加速溶剂提取(accelerated solvent extraction,ASE)由于提取速度快,溶  相似文献   

2.
刘颖  陈玲  唐银健  黄清辉  赵建夫 《色谱》2007,25(3):356-361
建立了高效液相色谱-二极管阵列检测器(PDA)测定上海市黄浦江表层沉积物中16种多环芳烃(PAHs)的方法。在保留时间定性分析的基础上,利用PDA获取的紫外扫描光谱图对目标组分进行了准确的定性,并通过异构体紫外光谱图中特征峰的差异有效地识别了样品中的4种异构体,即苯并[b]荧蒽、 苯并[k]荧蒽、 苯并[a]芘和苯并[e]芘。通过检测波长的优化,减少了干扰物的影响,提高了检测灵敏度;针对分离度较差的两种目标组分(苯并[b]荧蒽和苯并[k]荧蒽)的定量进行了分析讨论。该方法对16种PAHs的检出限(以干基计)介于1.1~18.3 ng/g之间,具有较高的方法灵敏度。黄浦江表层沉积物测定结果表明,除二氢苊外的15种PAHs都被检出,含量为10.1~253.0 ng/g。  相似文献   

3.
A simplified extraction method was developed for extracting high molecular weight polycyclic aromatic hydrocarbons (PAHs) from river sediments. The samples were extracted 3 times with 5 mL of solvent (toluene:methanol, 9 : 1, v/v) at 100 °C, 10 minutes for each extraction. After clean‐up and concentration, extracts were analyzed by gas chromatography coupled with mass spectrometer (GC‐MS). The extraction efficiency and accuracy was evaluated by the standard reference material (SRM‐1941b). Comparing to certified values, the average recoveries of high molecular weight PAHs with 3, 4, 5 and 6 fused benzene rings were 72.9∼113.2 % (R.S.D. 2.3∼6.3 %) except those of dibenz[a,h]anthracene (206.2±4.6 %). The average recoveries for PAHs spiked sediment samples were comparable with accelerated solvent extraction (ASE) and Soxhlet methods. The simple extraction method consumes less solvent, fewer amount of sample than those of conventional methods. The lowest quantitation limit of PAHs is 1.1 μg/kg.  相似文献   

4.
张剑辉  张宁  林昭  吴水平 《分析测试学报》2019,38(10):1171-1178
室内燃烧源排放颗粒物及其多环芳烃(PAHs)的粒径分布是定量评估室内人群呼吸暴露风险的重要参数之一。该研究在再悬浮箱内模拟燃香、燃蚊香、艾灸和吸烟等过程,采用MOUDI采样器采集和分析颗粒物中17种PAHs;同时,采用颗粒物计数器,在实际房间中模拟艾灸和吸烟过程,得到室内颗粒物数浓度的衰减曲线。结果表明,燃烧源烟雾颗粒的排放因子为3.68~22.46 mg/g,颗粒质量粒径呈单峰型,峰值为0.25~0.44μm;US EPA 16种优控PAHs的排放因子为10.52~91.30μg/g,艾绒燃烧排放PAHs的粒径峰值为0.44~1.0μm,略大于其它燃烧源;1μm颗粒中PAHs的BaP等效毒性当量(BaP_(TEQ))的贡献占比为85%~98%。来源特征比值的研究显示,艾灸、燃香和吸烟释放的PAHs均归属于生物质燃烧类别。实际室内监测显示,在艾绒和香烟燃烧后室内颗粒物数浓度快速上升,在燃尽时达到峰值,而后在4 h内呈指数规律衰减,且0.3μm的细颗粒衰减最快。  相似文献   

5.
《Analytical letters》2012,45(12):2201-2219
Abstract

A new on-line precolumn preconcentration method for the determination of EPA priority pollutants (PAHs) in river and sea water has been developed. The retention time for each PAH in the precolumn has been determined for several percentages of organic solvent (acetonitrile) in the sample. This is very important because recoveries show a great dependence on this parameter.

The proposed procedure, combined with HPLC and spectrofluorimetric detection, reaches very low detection limits (subnanograms per liter) and it has been applied to river and sea water samples with good results.  相似文献   

6.
Perilla frutescens (L.) Britt., a medicinal herb and edible plant, is very popular among East Asian countries. The perilla leaves, stems and seeds can be used as traditional medicines and foods. Polycyclic aromatic hydrocarbons (PAHs) and halogenated PAHs (HPAHs) are organic pollutants that are widely present in the environment, such as in water, air and soil, and are harmful to humans. In this study, the contents of 16 PAHs and 4 HPAHs in perilla leaves, stems and seeds were determined by gas chromatography tandem mass spectrometry (GC-MS). A total of 12 PAHs were detected in all samples, and no HPAHs were detected. The total contents of PAHs in perilla leaves, stems and seeds varied from 41.93 to 415.60 ng/g, 7.02 to 51.52 ng/g and 15.24 to 180.00 ng/g, respectively. The statistical analyses showed that there were significant differences in the distribution of PAHs in perilla leaves, stems and seeds. On the basis of the toxic equivalent quantity (TEQ) and incremental lifetime cancer risk (ILCR) model, the cancer risks of the intake of perilla leaves, stems and seeds were assessed to be from 3.30 × 10−8 to 2.11 × 10−5, 5.52 × 10−9 to 5.50 × 10−8 and 1.20 × 10−8 to 1.41 × 10−7, respectively. These were lower than 10−4 (the priority risk level of the EPA) and suggested that there may be almost no cancer risk from the intake of these traditional Chinese medicines (TCMs).  相似文献   

7.
Two internal standard surrogate (ISS) methods, ISS-I (with m-terphenyl as a single ISS) and ISS-2 (using five deuterated PAHs as a multi-ISS), for the determination of polycyclic aromatic hydrocarbons (PAHs) in mangrove sediments were compared. The recovery percentages of 16 PAHs except naphthalene in HS-6 (a certified reference material) were high, ranging from 69.3 to 111.8% for ISS-1 and from 71.8 to 120.3% for the ISS-2 method. Similarly, the PAH recovery percentages in spiked mangrove sediments and clean sand were lower for ISS-I than for ISS-2, but both methods met the accurate acceptance criteria for PAH recoveries. The reproducibility (i.e. the method precision) between the two ISS methods was also comparable and satisfactory, with relative standard deviation values in most cases within 20% of the data variability. These results indicate that both ISS methods were acceptable for the determination of PAHs in mangrove sediments, despite the fact that the matrix of mangrove sediments may interfere with the PAH recovery efficiency.  相似文献   

8.
多环芳烃暴露的生物标志物——尿中羟基多环芳烃   总被引:9,自引:0,他引:9  
多环芳烃(PAHs) 是典型的持久性有机污染物,在职业高PAHs 暴露环境下,容易诱发肺癌、皮肤癌等癌症。对PAHs 的暴露评价可为流行病学研究和污染物风险评价等提供有效的数据。由于暴露途径的复杂化,采用尿样中PAHs 的代谢产物———羟基多环芳烃作为标志物来综合评价人体对PAHs 的内暴露情况已经成为研究的热点。本文系统介绍了多环芳烃的吸收、代谢、尿中PAHs 代谢产物的主要存在形式、主要的生物标志物以及它们的主要影响因素。  相似文献   

9.
Abstract

Coral-rock oysters were collected in September 1982 from six locations in the area of Mermaid Sound in North-Western Australia. Analysis was carried out by digestion of the samples, followed by solvent extraction and analysis of the extracts using HPLCUVF and GC-MS.

The levels of two- and three-ring aromatics ranged from very low for the site outside Mermaid Sound and for one site within the Sound, to low for the four other sites within the Sound. The PAH values at the latter four sites are attributed to occasional petroleum release episodes related to small boat activities and large-scale salt and iron ore shipping and general cargo activities of the Port of Dampier.

The levels of PAHs with four or more rings were found to be low or very low at all sites; in fact, in most cases values measured for specific PAHs were below the limits of detection of even the very sensitive methods used in this study. Samples from sites within Mermaid Sound closest to the town and port of Dampier showed noticeably higher levels than those from outside; the present study does not allow the source of the PAHs to be determined. It is interesting to note, however, that the parent PAHs appear to form a greater proportion of the total PAH assemblage in these cases, indicating contributions from material which has been subjected to high temperature processing prior to release into the Sound.  相似文献   

10.
This paper assesses the occurrence, distribution, source, and toxicity of polycyclic aromatic hydrocarbons (PAHs), and their methylated form (Me-PAHs) in sewage sludge from 10 WWTPs in Northeastern China was noted. The concentrations of ∑PAHs, ∑Me-PAHs ranged from 567 to 5040 and 48.1 to 479 ng.g1dw, which is greater than the safety limit for sludge in agriculture in China. High and low molecular weight 4 and 2-ring PAHs and Me-PAHs in sludge were prevalent. The flux of sludge PAHs and Me-PAHs released from ten WWTPs, in Heilongjiang province, was calculated to be over 100 kg/year. Principal component analysis (PCA), diagnostic ratios and positive matrix factorization (PMF) determined a similar mixed pyrogenic and petrogenic source of sewage sludge. The average values of Benzo[a]pyrene was below the safe value of 600 ng.g1 dependent on an incremental lifetime cancer risk ILCR of 10−6. Sludge is an important source for the transfer of pollutants into the environment, such as PAHs and Me-PAHs. Consequently, greater consideration should be given to its widespread occurrence.  相似文献   

11.
Russian Journal of General Chemistry - Up-to-date data on the concentrations of priority PAHs in the sediments of Lake Baikal in 2019–2020 have been obtained by HPLC with fluorometric...  相似文献   

12.
提出了高效液相色谱法测定沉积物中多环芳烃(PAH′s)含量的方法。样品中多环芳烃用正己烷-丙酮(1+1)混合溶液超声提取,离心分离后,所得萃取液经蒸发浓缩,然后过装有1g无水硫酸钠和2g硅胶的层析柱净化。以Varian PAHs色谱柱为分离柱,不同比例配成的甲醇和水为流动相梯度洗脱,用荧光检测器检测。方法的检出限(3S/N)在0.34~1.52ng.g-1之间。方法用于沉积物中多环芳烃的测定,测定结果的相对标准偏差(n=5)在3.2%~10.6%之间。用标准加入法测定方法的回收率,结果在57.1%~103.4%之间  相似文献   

13.
The retention behaviour of 18 di-, tri- and tetra-fluorinated phenanthrenes, chrysenes and benzo[g]chrysenes in column liquid chromatography was studied for a monomeric and a polymeric octadecyl-bonded silica phase. The retention times were much longer than those of the parent compounds and strongly dependent on the F-substitution pattern. The influence of geometric factors like calculated length-to-breadth ratios (LB ratios) and planarity, and electronic factors such as dipole moment and London forces was investigated. A linear correlation was found between the dipole moment and/or the degree of fluorination and the retention factor for the monomeric phase, and additionally between the maximum LB ratio and the retention factor for the polymeric phase. These findings are interpreted using the models of partition and the slot-model, respectively. Polyfluorinated polycyclic aromatic hydrocarbons are not very similar to parent PAHs and are, therefore, less suitable as internal standards in PAH analysis than the monofluorinated analogues especially in cases when the similarity of physico-chemical properties is critical.  相似文献   

14.
本文利用主成分提取-线性判别分析(PCA-LDA)模型对多环芳烃(Polycyclic Aromatic Hydrocarbons,PAHs)的致癌性进行分类,与致癌性有关的多环芳烃的表面积、代谢活性区域中心碳原子的离域能、亲电活性区域中心碳原子的离域能以及分子脱毒区的总数四个参数作为模型的输入,用已知致癌性的67个样本作为训练集建立PCA-LDA模型,对10个预测集样本的致癌性进行预测,结果表明:致癌性按高(h)、低(l)、非(n)分类时预测准确率达100%。  相似文献   

15.
以γ-甲基吡啶(mPy)为模板剂合成了具有A型分子筛骨架结构的磷酸镓(GaPO4-LTA)单晶,并研究了mPy在GaPO4-LTA超笼内的高温热解反应.mPy在GaPO4-LTA笼中热解后形成稠环芳烃类物质PAHs(Polycyclicaromatichydrocarbons).这些PAHs物质的种类与升温速度和终止温度密切相关.在GaPO4-LTA笼中生成的PAHs可望成为合成富勒烯的前驱体.  相似文献   

16.
以二硫化碳为萃取剂,丙酮为分散剂对水样和土壤样中残留的多环芳烃进行分散液相微萃取。提取液供高效液相色谱仪的二极管阵列检测器和荧光检测器测定。选用LiChrospherPAH色谱柱作为固定相,用乙腈和水以不同比例混合的溶液作为流动相进行梯度淋洗。在优化的试验条件下,对合成水样中多环芳烃的富集倍数达220~560倍,16种多环芳烃可有效分离并测定。16种多环芳烃的检出限(3S/N)在0.002~0.05μg.L-1之间。用标准加入法测得回收率在64%~108%之间,测定值的相对标准偏差(n=7)在2.0%~7.8%之间。  相似文献   

17.
That polystyrene and benzene as additives to gasoline increase the amount of polycyclic aromatic hydrocarbons (PAHs) has been studied previously in our laboratory. This paper describes the use of carbon disulfide as the solvent instead of benzene brings a marked reduction of the formation of polycyclic aromatic hydrocarbons.  相似文献   

18.
Abstract

The toxicity of certain polycyclic aromatic hydrocarbons (PAHs) can be greatly increased by simultaneous exposure of test organisms to ultraviolet (UV) wavelengths present in sunlight. This phenomenon, commonly termed photoinduced toxicity, had been evaluated extensively in laboratory settings where only one chemical of concern was present. However, more recent studies have demonstrated that complex mixtures of PAHs present, for example in sediments, also can cause phototoxicity to a variety of aquatic species when the samples are tested in simulated sunlight. Unfortunately, because these types of samples can contain thousands of substituted and unsubstituted PAHs it is difficult, if not impossible, to use conventional analytical techniques to identify those responsible for photoinduced toxicity. The objective of the present study was to link two powerful ecotoxicology tools, toxicity-based fractionation techniques and QSAR models, to identify phototoxic chemicals in a sediment contaminated with PAHs emanating from an oil refinery. Extensive chromatographic fractionation of pore water from the sediment, in conjunction with toxicity testing, yielded a simplified set of sample fractions containing 12 PAHs that were identified via mass spectroscopy. Evaluation of these compounds using a recently developed QSAR model revealed that, based upon their HOMO-LUMO gap energies, about half were capable of producing photoinduced toxicity. We further evaluated the phototoxic potential of the reduced set of PAHs by determining their propensity to bioaccumulate in test organisms, through calculation of octanol-water partition coefficients for the chemicals. These studies represent a novel linkage of sample fractionation methods with QSAR models for conducting an ecological risk assessment.  相似文献   

19.
A sedimentary record of the 16 polycyclic aromatic hydrocarbon (PAH) pollutants from Dongping Lake, north China, is presented in this study. The influence of regional energy structure changes for 2–6-ring PAHs was investigated, in order to assess their sources and the impact of socioeconomic developments on the observed changes in concentration over time. The concentration of the ΣPAH16 ranged from 77.6 to 628.0 ng/g. Prior to the 1970s, the relatively low concentration of ΣPAH16 and the average presence of 44.4% 2,3-ring PAHs indicated that pyrogenic combustion from grass, wood, and coal was the main source of PAHs. The rapid increase in the concentration of 2,3-ring PAHs between the 1970s and 2006 was attributed to the growth of the urban population and the coal consumption, following the implementation of the Reform and Open Policy in 1978. The source apportionment, which was assessed using a positive matrix factorization model, revealed that coal combustion was the most important regional source of PAHs pollution (>51.0%). The PAHs were mainly transported to the site from the surrounding regions by atmospheric deposition rather than direct discharge.  相似文献   

20.
致癌性多环芳烃萘、蒽、芘的分析方法比较   总被引:3,自引:1,他引:3  
利用薄层色谱(TLC)、紫外光谱(UV)、反相高效液相色谱(RPHPLC)对多环芳烃(PAHs)萘、蒽、芘的分析方法进行了研究。TLC中使用环己烷:氯仿(5:4,V/V)作为展开剂时,三者的R,值分别为0.78、0.65和0.72;用UV法在溶液中测定了三者的最大吸收波长分别为303、380、338nm;当流动相为甲醇:水(9:1,V/V)时三者在RP—HPLC中的保留时间为4.179、5.190、6.178min,5次重复RSD分别为1.1%、1.8%、0.91%,并用于实际水样中萘、蒽、芘的分析。  相似文献   

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