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1.
常州市秋季大气PM2.5中多环芳烃污染水平及来源   总被引:2,自引:0,他引:2  
为了研究常州市秋季大气PM2.5中多环芳烃的污染水平及其来源,在常州市布设了6个采样点,分别代表交通干道区、商业混合区、居民文教区、远郊区、工业区和对照点,于2013年10月进行大气PM2.5的采样,采用微波萃取-高效液相色谱法测定其中16种USEPA优控多环芳烃的浓度值,并分别通过比值法和因子分析法判断其主要来源。结果表明,常州市秋季大气PM2.5中多环芳烃的主要来源为煤燃烧和机动车排放。  相似文献   

2.
The distribution and composition of hydrocarbons in sediment from the Fladen Ground oilfield in the northern North Sea have been investigated. The total PAH concentrations (2- to 6-ring parent and alkylated PAHs, including the 16 US EPA PAHs) in sediments were relatively low (<100 microg kg(-1) dry weight). The PAH, the Forties crude and diesel oil equivalent concentrations were generally higher in sediment of fine grain size and higher organic carbon concentration. PAH distributions and concentration ratios indicated a predominantly pyrolytic input, being dominated by the heavier, more persistent, 5- and 6-ring compounds, and with a high proportion of parent PAHs. The n-alkane profiles of a number of the sediments contained small, high boiling point, UCMs, indicative of weathered oil arising from a limited petrogenic input. The geochemical biomarker profiles of the sediments that contained UCMs showed a small bisnorhopane peak and a high proportion of norhopane relative to hopane, indicating that there was contamination from both Middle Eastern and North Sea oils. Therefore contamination was not directly as a result of oil exploration activity in the area. The most likely source of petrogenic contamination was from general shipping activity.  相似文献   

3.
Ambient air particulates were collected using high volume samplers at seven locations throughout Singapore. The particulates were analyzed for eleven polynuclear aromatic hydrocarbons (PAH) using high performance liquid chromatography (HPLC) with fluorescence detection. Several sample preparation techniques were used to determine which method would yield the most PAHs from the bulk sample matrix. PAH profiles (standardised against the concentration of benzo(a)pyrene) were obtained to characterise the different sampling sites chosen.  相似文献   

4.
The concentrations of fifteen PAH compounds in samples of sediment and blue mussel tissue (Mytilus trossulus) were measured. In addition, the biliary polycyclic aromatic hydrocarbon metabolites present in flounder (Platichthys flesus) were analysed. Two methods were used in the analysis of PAH metabolites; high performance liquid chromatography (HPLC) and fixed wavelength fluorescence (FF). The major PAH metabolite which could be measured using the HPLC method was 1-OH pyrene. It was possible to detect 1-OH Phe and 3-OH B[a]P in 70 and 24 samples respectively, of the 87 samples analysed. However, the concentrations of 1-OH Phe and 3-OH B[a]P were below or near to the LOQ (0.002 μg ml(-1) bile). The bile of flounder samples from the Gulf of Gdańsk had 1-OH Pyr concentrations which ranged from 0.019 to 0.066 μg ml(-1) bile. The high linear correlation observed between the quantity of 1-OH pyrene determined by the HPLC-F method and the content of the sum of pyrene-type PAHs obtained by the FF method indicated the FF method of determination of pyrene-type PAH metabolites can be used as a screening method. The content of ∑(15)PAHs in sediments collected in the Gulf of Gdansk, in 2008, ranged from 29.3 to 103 μg kg(-1) dw. In mussel tissue ∑(15)PAHs concentrations were between 173.2 μg kg(-1) dw and 237.7 μg kg(-1) dw. All concentrations measured in the current study, in mussel tissue, were below the OSPAR toxicity threshold values.  相似文献   

5.
Total suspended particle samples and gas phase samples were collected at three representative sampling sites in the southeastern suburb of Beijing from March 2005 to January 2006. The samples were analyzed for 16 US EPA priority PAHs using GC/MS. Concentrations of Sigma PAHs in particle and gas phases were 0.21-1.18 x 10(3) ng m(-3) and 9.5 x 10(2) ng-1.03 x 10(5) ng m(-3), respectively. PAH concentrations displayed seasonal variation in the order of winter>spring>autumn>summer for particle phase, and winter>autumn>summer>spring for gas phase. Partial correlation analysis indicates that PAH concentrations in particle phase are negatively correlated with temperature and positively correlated with air pollution index of SO(2). No significant correlation is observed between gas phase PAHs and the auxiliary parameters. Sources of PAH are identified through principal component analysis, and source contributions are estimated through multiple linear regression. Major sources of atmospheric PAHs in the study area include coal combustion, coke industry, vehicular emission and natural gas combustion.  相似文献   

6.
A method for the determination of polycyclic aromatic hydrocarbons (PAHs) in air particulates using microwave-assisted solvent extraction (MASE) coupled to a microwave extraction system (MES) is proposed. During the period of August to October, 1994, Singapore was enveloped by haze caused by forest fires in Sumatra, Indonesia. Air sampling were carried out during September and October; the determination of ambient air PAH levels in Singapore was undertaken. PAH analysis by GC-MS provided excellent sensitivity, linearity of quantitation, peak identification. This technique was evaluated using certified reference materials (CRMs) HS-4 and HS-6. Good recoveries of PAHs (>73.3%) were obtained for both CRMs. The MASE technique using MES is suitable for the determination of PAH levels in ambient air with no clean-up step required.  相似文献   

7.
以煤矿区及煤矸石的污染特征为依据,选取16种EPA优先控制多环芳烃(PAHs)污染物,采用高效液相色谱法对不同堆积年限的矿区煤矸石山周围塌陷区的水体样品进行测试,分别分析此类水体中单个PAHs和总PAHs的分布情况及水体中PAHs不同环数的组成情况,并采用风险商值法进行水体生态风险评价,指出此类水体的不当开发利用会引起人体健康危害。  相似文献   

8.
A sonication method was compared with Soxhlet extraction for recovering polycyclic aromatic hydrocarbons (PAH) from a clay soil that had been contaminated with tar materials for several decades. Using sonication over an 8 h extraction period, maximum extraction of the 16 US EPA priority PAH was obtained with dichloromethane (DCM)-acetone (1 + 1). The same procedure using hexane-acetone (1 + 1) recovered 86% of that obtained using DCM-acetone (1 + 1). PAH recovery was dependent on time of extraction up to a period of 8 h. The sonication procedure showed that individual PAH are extracted at differing rates depending on the number of fused rings in the molecule. Soxhlet extraction [with DCM-acetone (1 + 1)] over an 8 h period recovered 95% of the PAH removed by the sonication procedure using DCM-acetone (1 + 1), indicating that rigorous sonication can achieve PAH recoveries similar to those obtained by Soxhlet extraction. The lower recovery with the Soxhlet extraction was explained by the observed losses of the volatile PAH components after 1-4 h of extraction. The type of solvent used, the length of time of extraction and extraction method influenced the quantification of PAH in the soil. Therefore, the study has implications for PAH analyses in soils and sediments, and particularly for contaminated site assessments where the data from commercial laboratories are being used. The study emphasizes the importance of establishing (and being consistent in the application of) a vigorous extraction, particularly for commercial laboratories that handle samples of soil in batches (at different times) from a single site investigation or remediation process. The strong binding of PAH to soil, forming aged residues, has significant implications for extraction efficiency. This paper illustrates the problem of the underestimation of PAH using the US EPA method 3550, specifically where a surrogate spike is routinely employed and the efficiency of the extraction procedure for aged residues is unknown. The implications of this study for environmental monitoring, particularly where numerous batches of samples from a single site assessment or remediation program are submitted to commercial laboratories, is that it would be advisable for these laboratories to check their existing method's extraction efficiencies by conducting a time course sonication extraction on their particular soil to determine the optimum extraction time.  相似文献   

9.
The purpose of this study was to evaluate the effects of cyclodextrin (CD) on the extraction of Macondo well oil from contaminated porous media over a range of hydroxypropyl-β-CD (HPβCD) concentrations. To our knowledge, this is the first dataset on this type of CD yet assembled for an actual crude oil. The results showed that HPβCD can significantly increase oil extraction efficiency, demonstrated by increasing concentrations of all tested normal alkanes (nC(15)-nC(35)) and polyaromatic hydrocarbons (PAHs) in the aqueous phase with increasing CD concentration. A linear relationship between the extraction enhancement effect and CD concentration were verified experimentally and high correlation coefficients for total PAHs (R(2) = 0.82) and alkanes (R(2) = 0.99) were determined. For a 20% CD solution, 3.13 wt% of alkanes and 32.12 wt% of total PAHs were extracted to the aqueous phase, which was significantly more than what was extracted with water only (0.04% and 0.21% for alkanes and PAHs, respectively). This result shows that the remediation of oil contaminated media can be significantly enhanced through the use of HPβCD solutions in flushing or pump and treat operations to remove sorbed oil. The CD extraction enhancement effect decreases with increasing n-alkane chain length for the carbon number range tested. CD significantly enhanced PAH extraction from sand and the enhancement effect increased in the order of parent compounds < C-1 substituted < C-2 substituted < C-3 substituted for most PAHs tested. This study provides important information to assess the feasibility of using CD as a near-shore agent to enhance the cleanup of oil contaminated porous media.  相似文献   

10.
建立了用膜-柱串联固相萃取(SPE)技术,甲醇和水作为流动相进行梯度洗脱,紫外和荧光检测器串联的高效液相色谱法(HPLC)分析水中EPA优先监控的16种PAHs的方法.  相似文献   

11.
Diesel-powered equipment is known to emit significant quantities of fine particulate matter to the atmosphere. Numerous organic compounds can be adsorbed onto the surfaces of these inhalable particles, among which polycyclic aromatic hydrocarbons (PAHs) are considered potential occupational carcinogens. Guidelines have been established by various agencies regarding diesel emissions and various control technologies are under development. The purpose of this study is to identify, quantify and compare the organic compounds in diesel particulate matter (DPM) with the diesel fuel and engine oil used in a non-road diesel generator. Approximately 90 organic compounds were quantified (with molecular weight ranging from 120 to 350), which include alkanes, PAHs, alkylated PAHs, alkylbenzenes and alkanoic acids. The low sulfur diesel fuel contains 61% alkanes and 7.1% of PAHs. The identifiable portion of the engine oil contains mainly the alkanoic and benzoic acids. The composition of DPM suggests that they may be originated from unburned diesel fuel, engine oil evaporation and combustion generated products. Compared with diesel fuel, DPM contains fewer fractions of alkanes and more PAH compounds, with the shift toward higher molecular weight ones. The enrichment of compounds with higher molecular weight in DPM may be combustion related (pyrogenic).  相似文献   

12.
Polycyclic aromatic hydrocarbons (16 EPA-PAHs) in urban surface soil from Jiaxing City were determined using HPLC. The total concentration of 16 EPA-PAHs was detected from 18.73 to 441.34 pg/g. Individual PAH occupation analysis demonstrates that four-ring PAHs comprise as much as 44.16% and were prevalent in the composition of PAH pollutants. The other components were two-ring PAHs (7.36%), three-ring PAHs (17.28%), five-ring PAHs (16.16%), and six-ring PAHs (15.04%). Source analysis on the characteristic ratios of anthracene(Ane)/[Ane+phenanthrene(Phe)], fluoranthene(Fla)/[Fla+pyrene(Pyr)], and benzo[a]pyrene(Bap)/benzo[g,h,i]perylene(Bgp) reveals that PAH pollutants originated mainly from coal combustion, but vehicular emission as a source was not negligible. All PAHs discussed in the paper have similar source in most sampling sites. The spatial distributions of pollution sources were closely related to geographic location, geographic condition, and living habit of indigenes. A linear relationship between 2-3-ring PAHs, 4-6-ring PAHs, SOM, and ∑PAHs were investigated and significant correlativity were expatiated lastly. It revealed that coefficient between 2-3-ring PAHs and ∑PAHs is 0.56, between 4-6-ring PAHs and ∑PAHs is 0.99, between SOM and ∑PAHs is 0.82.  相似文献   

13.
Inhalation of emissions from petrol and diesel exhaust particulates is associated with potentially severe biological effects. In the present study, polycyclic aromatic hydrocarbons (PAHs) were identified from smokes released by the automobile exhaust from petrol and diesel. Intensive sampling of unleaded petrol and diesel exhaust were done by using 800-cm3 motor car and 3,455-cm3 vehicle, respectively. The particulate phase of exhaust was collected on Whatman filter paper. Particulate matters were extracted from filter paper by using Soxhlet. PAHs were identified from particulate matter by reverse phase high performance liquid chromatography using C18 column. A total of 14 PAHs were identified in petrol and 13 in case of diesel sample after comparing to standard samples for PAH estimation. These inhalable PAHs released from diesel and petrol exhaust are known to possess mutagenic and carcinogenic activity, which may present a potential risk for the health of inhabitants.  相似文献   

14.
To estimate the severity of polycyclic aromatic hydrocarbon (PAH) contamination in the upper sediment of the Beijiang River, 42 sediment samples were analyzed for the presence of 16 key PAHs using gas chromatography–mass spectrometry. The concentrations of PAH in the sediment ranged from 44 to 8,921 ng g?1 dry weight. The four- to six-ring PAHs, contributing >50 % to PAHs in 34 of the 42 sites, were the dominant species. Based on a principal component analysis, combined with multivariate linear regression, it became clear that the most important contributors of PAH were fossil fuel combustion (48 %), diesel emissions plus oil spillage (33 %), and coke combustion (19 %). The surface sediments of Beijiang River were grossly contaminated by PAHs mainly derived from combustion.  相似文献   

15.
In the last decade, the development of novel analytical methodologies enabled the identification of several environmental pollutants responsible for health problems associated with indoor exposure. Polycyclic aromatic hydrocarbons (PAHs) are among the potential hazardous chemicals present in ambient air. Due to their bioaccumulation potential and carcinogenic/mutagenic effects, 16 PAHs are currently listed as priority air pollutants. The main goal of this work was to implement a new and simple method for sampling and determination of PAHs in air by using a thermal desorption (TD) technique followed by gas chromatography coupled with mass spectrometry analysis. A detailed study was carried out to optimise the experimental method in each of its phases, including (active) sampling, TD and chromatographic analysis. The results demonstrate that this approach allowed the detection and quantification of the six more volatile PAHs, namely, naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, and anthracene. Acceptable precision and good linearity over the explored range were obtained. No carry-over was observed during experimental tests and the method provided a reproducible answer. The applicability of the novel methodology was tested in real environment, namely, on the roof of a building in an urban area, in a domestic kitchen and in a collective car garage. The method enabled the identification of two PAHs in the field samples, specifically, naphthalene (two rings) and phenanthrene (three rings). With regard to PAHs sample composition, the most abundant PAH found, in the three different locations, was naphthalene, accounting for about 84–100 % of the total PAH mass detected.  相似文献   

16.
Exposure to diesel exhaust was evaluated in summer and winter by measuring vapour and particle phase polycyclic aromatic hydrocarbons (PAHs). Fifteen PAHs were simultaneously determined from the air samples obtained from truck drivers collecting household waste and maintenance personnel at a waste handling centre. The major compounds analysed from the personal air samples of exposed workers were naphthalene, phenanthrene and fluorene. The total PAH exposure (sum of 15 PAHs) of garbage truck drivers ranged from 71 to 2,660 ng m(-3) and from 68 to 900 ng m-3 in the maintenance work. The exposure of garbage truck drivers to benzo[a]pyrene (B[a]P) ranged from the mean of 0.03 to 0.3 ng m(-3) whereas no B[a]P in control samples or in those collected from maintenance workers was detected. A statistically significant difference in diesel-derived PAH exposure between the garbage truck drivers and the control group in both seasons (in summer p = 0.0022, degrees of freedom (df) 70.5; and in winter p < 0.0001, df = 80.4) was observed. Also, a significant difference in PAH exposure between the garbage truck drivers and the maintenance workers (in summer p < 0.0001, df = 50.1; and in winter p < 0.0001, df = 44.2) was obtained.  相似文献   

17.
PAHs Contamination in Bank Sediment of the Yamuna River, Delhi, India   总被引:2,自引:0,他引:2  
This study was performed to elucidate the distribution, concentration trend and possible sources of PAHs in bank sediment of river Yamuna in Delhi, India. The levels of 16 priority polycyclic aromatic hydrocarbons (PAHs) were analyzed during pre-monsoon, monsoon and post-monsoon seasons in the sediment fraction < 53 μm. Reference standards and internal standards were used for identification and quantification of PAHs by HPLC. The sum of 16 PAH compounds ranged from 4.50 to 23.53 μg/g with a mean concentration of 10.15 ± 4.32 μg/g (dry wt.). Among 5 sites studied, the site, Income Tax Office (ITO) was found to be the hotspot attaining highest concentration. Predominance of 2–4 ring PAHs suggests a relatively recent local sources of PAHs in the study area. Moreover, molecular indices based source apportionment also illustrates pyrogenic source fingerprint of PAHs. No significant temporal trend was observed.  相似文献   

18.
In this paper, improvements obtained by using focused microwaves for extraction, in the analysis of polycyclic aromatic hydrocarbons (PAHs) adsorbed on particulate matter, are discussed. The method was tested on the following PAHs, which are considered to be among the most harmful with regard to carcinogenicity: benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, dibenzo[a,h]anthracene. The extraction of PAHs and concentration of the sample can be performed in 3 h with a recovery of at least 70% and a maximum standard deviation of 4%. These steps are followed by clean-up on a SPE (solid-phase extraction) cartridge and analysis by GC-MS. Real samples collected in the urban area of Bari were analysed according to the proposed procedure.  相似文献   

19.
The levels and possible sources of 16 priority polycyclic aromatic carbons (PAHs) in the sediments from the Yellow River Delta (YRD) were investigated. The total PAH concentrations ranged from 23.9 to 520.6 microg kg(-1) with a mean value of 150.9 microg kg(-1), indicating low or medium levels compared with reported values of other deltas. The concentrations of the 16 individual PAHs presented varied profiles among different regions. The ecological risk assessment of PAHs showed that adverse effects would rarely occur in the sediments of the YRD based on the effect range-low quotients and the probability risk assessment. The PAH compositions and the principal component analysis (PCA) with multiple linear regression (MLR) uniformly presumed the mixed sources of pyrogenic- and petrogenic-deriving PAHs in the YRD. By PCA with MLR, the contributions of major sources were quantified as 36.4% from oil burning, 33.1% from biomass combustion, and 30.5% from diesel emission sources.  相似文献   

20.
多环芳烃(PAHs)是一类极其复杂的有机污染物,衍生物种类较多,1976年美国环保局因其致癌、致畸、致突变将其中的16种列为优先控制污染物。城市污水处理厂作为一个地区污染物迁移和转化的重要媒介,在控制和截断PAHs进入天然水体的过程中扮演着重要的角色。因此,研究污水处理厂中PAHs的浓度水平对于了解和控制PAHs进入天然水体和通过污泥进入到土壤中进而通过食物链危害人类健康具有重要的意义。文章综述了污水处理厂污水和污泥中PAHs的前处理技术、分析方法、浓度水平、生态风险以及国内外污水处理厂污泥土地利用现状。  相似文献   

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