Quantitative analysis of polycyclic aromatic hydrocarbons in sewage sludge from wastewater treatment plants.

Polycyclic aromatic hydrocarbons (PAHs) are an important group of organic contaminants present in sewage sludge. Due to their persistence and toxic potential, information about their presence in sewage sludge is needed in order to assess applicability on agricultural land. A method for the gas chromatographic-mass spectrometric (GC-MS) determination was developed and applied to the trace determination of PAHs present in sewage sludge samples from six wastewater treatment plants (WWTPs) differing in the type of treatment and the origin of wastewater. PAHs were extracted from freeze-dried samples by a dichloromethane-methanol (2:1) mixture in a sonication bath. The sludge extracts were cleaned-up by an alumina column. The method showed recovery values varying from 60 to 98%. Four surrogate standards ([2H8]naphthalene, [2H10]anthracene, [2H12]benzo[a]anthracene, and [2H12]benzo[ghi]perylene) were used for quantitation by GC-MS. A reference sludge sample was analysed in order to validate the method. The sum of the 16 US Environmental Protection Agency PAHs analysed in the sewage sludge samples varied from 1.13 to 5.52 mg/kg. No significant difference between the different WWTPs was found.     

Optimization of the matrix solid-phase dispersion sample preparation procedure for analysis of polycyclic aromatic hydrocarbons in soils: comparison with microwave-assisted extraction

A fast and simple preparation procedure based on the matrix solid-phase dispersion (MSPD) technique is proposed for the first time for the isolation of 16 polycyclic aromatic hydrocarbons (PAHs) from soil samples. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-c,d]pyrene were considered in the study. Extraction and clean-up of samples were carried out in a single step. The main parameters that affect extraction yield, such as dispersant, type and amount of additives, clean-up co-sorbent and extractive solvent were evaluated and optimized. The addition of an alkali solution in MSPD was required to provide quantitative recoveries. Analytical determinations were carried out by high performance liquid chromatography (HPLC) with fluorescence detection. Quantification limits (between 0.01 and 0.6 ng g(-1) dry mass) were well below the regulatory limits for all the compounds considered. The extraction yields for the different compounds obtained by MSPD were compared with the yields obtained by microwave-assisted extraction (MAE). To test the accuracy of the MSPD technique, the optimized methodology was applied to the analysis of standard reference material BCR-524 (contaminated industrial soil), with excellent results.     

Collection and analytical characterisation of the atmospheric particulate in the city of Bari

In this paper an application of new procedures for atmospheric particulate analysis is illustrated. PM10, PAHs (benzo[a]anthracene (BaA), benzo[b]fluoranthene (BbF), benzo[j]fluoranthene (BjF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), indeno[1, 2, 3-cd]pyrene (Ip), dibenzo[a, h]anthracene (DbA)) and heavy metals (Cu, Ni, Zn, Co, Mn, Cd, Fe and Pb) were investigated. PM10 determination was performed by gravimetric method, PAHs were measured by GC-MS, and heavy metals by HPIC. An air quality monitoring campaign on the territory of Bari municipality has been organised, and its results are shown.     

Resolution of 13 polycyclic aromatic hydrocarbons by constant-wavelength synchronous spectrofluorometry.

A method capable of determining 13 PAHs (acenaphthene, anthracene, benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, chrysene, dibenzo[ah]anthracene, fluoranthene, fluorene, indene[1,2,3-cd]pyrene, phenanthrene and pyrene) in a mixture of 16 EPA PAHs by second derivative synchronous spectrofluorometry in the constant wavelength mode was developed. It has not been possible to determine the following PAHs in the mixture: acenaphthylene, benzo[ghi]perylene and naphthalene. The approach studied allows the sensitive, rapid and inexpensive identification and quantitation of 13 PAHs in a solution of hexane. The detection limits are <1 microg L(-1) (except for chrysene and phenanthrene).     

ASE-SPE/GC-MS测定土壤中16种PAHs质量控制研究

优化了土壤中16种优控多环芳烃( PAHs)的分析方法,建立了一套完备的质量控制体系,解决了PAHs分析中常见的技术难点,如苯并(a)芘(BaP)回收率低,基质复杂的样品净化效果不理想,萘(Nap)和菲(Phe)挥发损失和环境本底影响等.样品经加速溶剂提取(ASE),固相萃取(SPE)净化,逐级减压浓缩,气相色谱质谱( GC - MS)测定,并以氘代苯并a芘(BaP - d12)作回收率指示物.实验比较了3种正相SPE吸附剂的效果,发现弗罗里硅土对BaP存在明显的降解现象,BaP的定量应使用同位素稀释法,以降低其分析不确定度;氧化铝对PAHs的吸附性过强,不利于样品净化;硅胶最为理想.PAHs的仪器检出限为0.26～5.7 pg,方法检出限为0.067 ～0.97 ng/g(干重),土壤基质加标回收率为71％～ 122％,相对标准偏差为1.6％～8.3％.将该法用于7个电子废物焚烧区域农田土壤样品的测定,PAHs含量在28～ 283 ng/g(干重)之间,样品中BaP-d12的回收率为90％～124％,各项质控指标符合检测要求.     

中空结构的双金属有机骨架材料作为固相微萃取纤维涂层用于多环芳烃的高灵敏检测

环境样品中多环芳烃(PAHs)含量较低且样品基质复杂,直接利用仪器进行含量测定比较困难,因此在仪器分析之前需要对环境样品进行必要的前处理。大多数前处理技术的萃取效率取决于萃取材料的特性。目前,金属有机骨架材料(MOFs)作为一种由金属离子与有机配体自组装而成的多孔材料,已经被用作固相微萃取(SPME)的涂层材料应用于PAHs的萃取,但是这些MOFs涂层材料由于目标物较难达到其深层的吸附位点,使得萃取过程往往需要较长的平衡时间;此外,大多数MOFs由单金属离子配位构成,能够提供的开放金属活性位点种类比较单一,较难获得最佳的萃取性能。这些问题在一定程度上限制了MOFs材料在SPME领域的应用。该研究制备了一种中空结构的双金属有机骨架材料(H-BiMOF),并将其作为SPME的涂层材料,用于萃取环境样品中痕量的PAHs。由于中空的结构和双金属的组成,H-BiMOF涂层材料拥有比表面积利用率高、传质距离短等优点,可以使萃取过程快速地达到平衡。同时,双金属的引入提供了种类丰富的金属活性位点,提高了对PAHs这类富电子云目标物的萃取效率。与气相色谱-串联质谱(GC-MS/MS)相结合,建立了一种用于环境水样中PAHs分析的新方法。所建立的分析方法具有检出限低(0.01~0.08 ng/L)、线性范围宽(0.03~500.0 ng/L)、重复性良好(相对标准偏差≤9.8%, n=5)等优点,并成功地用于实际湖水样品中7种PAHs的检测。实验结果表明,所建立的分析方法适用于环境样品中PAHs的分析与监测。     

Supercritical fluid extraction of polycyclic aromatic hydrocarbons from liver samples and determination by HPLC-FL

An extraction/clean-up procedure by SFE was developed for isolating PAHs from liver samples for subsequent HPLC-FL determination of ten PAHs in the enriched extract. Recoveries (90-115%) and RSD % (< or =7.7) were satisfactory. When applied to 11 samples of bird of prey (Tyto alba) protected species and classified of special interest, from the Galicia (Northwest to Spain), benzo[ghi]perylene and indeno[1,2,3-cd]pyrene were undetectable; chrysene and benzo[a]pyrene are only detected in one sample; benzo[a]anthracene and benzo[k]fluoranthene are only quantified in one sample and benzo[b]fluoranthene in two samples. The other PAHs, anthracene, fluoranthene and pyrene are present in almost all the samples.     

Polycyclic aromatic hydrocarbons (PAHs) in edible oils by gas chromatography coupled with mass spectroscopy

The occurrence of polycyclic aromatic hydrocarbons (PAHs) in nine edible oils of three categories of oil samples, such as soy bean oil, mustard oil and coconut oil, has been studied to determine the contamination degree of this type of oil samples. Eight major carcinogenic polycyclic aromatic hydrocarbons (PAHs), such as naphthalene, anthracene, phenanthrene, fluorene, pyrene, crysene, benzo(a)pyrene and benzo(a)anthracene, were identified and quantified in the extract of edible oils collected from Bangladeshi Markets by gas chromatography and mass spectroscopy. All of the carcinogenic PAHs are not present in the edible oils. A few of the carcinogenic PAHs are present in the oils but it is within the permissible limit. The results for the recoveries of naphthalene, fluorene, phenanthrene, anthracene, pyrene, crysene, benzo(a)anthracene and benzo(a)pyrene were in the range of 56–84%. The limit of detection (LOD) of the GC–MS method, established at signals three times that of the noise for naphthalene, fluorene, phenanthrene, anthracene, pyrene, crysene, benzo(a)anthracene and benzo(a)pyrene, was 2.0–2.5 ng, respectively.     

Determination of polycyclic aromatic hydrocarbons by gas chromatography–mass spectrometry in soils from Southeastern Romania

Gas chromatography–mass spectrometry was used for the determination of 16 priority polycyclic aromatic hydrocarbons (PAHs) in surface soils from seventeen areas in Southeast Romania, including sites placed in the vicinity of Galati iron and steel plant and Lower Prut Meadow natural reserve in Galati County. The total concentration of PAHs (TPAHs) in the investigated soils ranges from 0.003 mg/kg to 38.524 mg/kg dry weight. According to Romanian legislation for trace organic compounds in soils of different uses, the amounts of PAHs in soils from the industrial zone exceed the normal values for the majority of individual PAHs. The lowest concentrations were found in soils sampled from the protected area of Lower Prut Meadow natural reserve and the highest near a zootechnique farm in the Prut River basin, where the alert levels exceeded for the less sensitive area in the case of TPAHs and benzo[b]fluoranthene and for the sensitive area in the case of chrysene, benz[a]anthracene, benzo[k]fluoranthene and benzo[g,h,i]perylene. The sources of PAH contaminating soils are complex, being of both pyrogenic and petrogenic origins.     

Isotope dilution determination of polycyclic aromatic hydrocarbons in olive pomace oil by gas chromatography-mass spectrometry

A gas chromatographic (GC) method with mass spectrometry detection (MS) for the determination of eight polycyclic aromatic hydrocarbons (PAHs) in olive pomace oil has been developed. The oil was diluted with n-pentane and extracted by liquid-liquid partition with dimethyl sulphoxide (DMSO). After water addition and back-extraction with cyclohexane, a thin-layer chromatography on silica gel was performed as a further purification step. The PAHs spot was scraped off from the plate and the final extract was concentrated and analysed by GC-MS in full scan mode. The eight PAHs under investigation were determined in the presence of the corresponding labelled compounds added as internal standards to the sample at the beginning of the analytical process. The identified PAHs were then quantified by the isotope dilution methodology assuring the compensation of the concentration of each analyte for any variation in the sample preparation. The method precision was satisfactory with relative standard deviation (R.S.D.) values in the range 3.6-12.7% for all PAHs. The average recovery rates ranged from 69.0 to 97.5%. Accuracy was also calculated for benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene and benzo[ghi]perylene by analysing a certified reference material (CRM 458, coconut oil) with adequate results. All response curves exhibited a linear fit from 0.1 to 10 microg ml(-1) and the determination coefficients R2 were better than 0.9942. The limits of detection (0.1-0.4 microg kg(-1)) were acceptable when compared with the maximum permitted limit of 2 microg kg(-1) for each of the eight considered PAHs and 5 microg kg(-1) for the sum of the eight PAHs established by the Italian legislation. Measurement uncertainty was finally calculated identifying and quantifying the uncertainty components of the analytical process. The relative expanded uncertainties (Uc), expressed as percent values were in the range 8.5-11.4% thus appropriate for residues quantification in the range of concentrations considered in the present study.     

Sources and distribution of polycyclic aromatic hydrocarbons (PAHs) in sediments from the Mar Piccolo of Taranto,Ionian Sea,southern Italy

The concentrations of 17 parent PAHs, with molecular weight from 128 to 278 Daltons, were determined in surface sediments from the Mar Piccolo of Taranto. The analytical results were compared with the published results for other coastal areas of the Mediterranean Sea. The analyses were performed by gas chromatography coupled to mass spectrometry (GC-MS). Total PAH content in sediments ranged from 380 to 12750 ng g(-1) dry weight. The levels of the PAHs was higher than the one reported for sediments of the Adriatic Sea and Cretan Sea and of the same order of magnitude of the one known for coastal areas of the western and the eastern Mediterranean Sea. The PAHs distribution showed similar patterns in all sediments analyzed, with compounds with three or more rings. These patterns of distribution and the ratios among low molecular weight PAHs/high molecular weight PAHs, phenanthrene/anthracene and fluoranthene/pyrene indicated that pyrogenic inputs are the main source of these compounds in the Mar Piccolo basin. Based on the comparison of both the individual and the total PAH concentrations with proposed sediment quality guidelines, the acute biological effects on the marine organisms should be negligible.     

Distribution and occurence of polycyclic aromatic hydrocarbons (PAHs) in sediments from the Mar Grande and Gulf of Taranto (Ionian Sea, southern Italy)

Marine sediments from the Mar Grande and Gulf of Taranto were analysed for 17 parent PAHs, with molecular weight from 128 to 278 Daltons. The analyses were performed by gas chromatography coupled to mass spectrometry (GC-MS). Total PAHs content in sediments ranged from 464 to 12522 microg kg(-1) dry wt for Mar Grande and from 593 to 72275 microg kg(-1) dry wt for Gulf of Taranto. The analytical results were compared with the published results for other coastal areas in the Mediterranean Sea. PAHs levels in the Gulf of Taranto sediments were the highest in the Mediterranean sea, while PAHs concentrations in Mar Grande were higher than the ones reported in the Adriatic and Cretan Sea and with the same order of magnitude of the ones known for coastal areas of the Western and the Eastern Mediterranean Sea. PAHs concentration ratios were consistent with the main source of these compounds, in most areas, being pyrolysis. Based on the comparison of both the individual and the total PAHs concentrations with proposed sediment quality guidelines, the acute biological effects on the marine organisms were probable, especially for the Gulf of Taranto, in which almost all PAHs concentrations in sediments were higher than the guidelines limit values. The statistical analysis effected by HCA and PCA methods was used in order to classify sediment samples and to identify accumulation areas.     

Interpretative optimization and artificial neural network modeling of the gas chromatographic separation of polycyclic aromatic hydrocarbons

An interpretative strategy (factorial design experimentation+total resolution analysis+chromatogram simulation) was employed to optimize the separation of 16 polycyclic aromatic hydrocarbons (PAHs) (naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo(a)anthracene, benzo(k)fluoranthene, benzo(b)fluoranthene, benzo(a)pyrene, indeno(1,2,3-c,d)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene) in temperature-programmed gas chromatography (GC). Also, the retention behavior of PAHs in the same GC system was studied by a feed-forward artificial neural network (ANN). GC separation was investigated as a function of one (linear temperature ramp) or two (linear temperature ramp+the final hold temperature) variables. The applied interpretative approach resulted in rather good agreement between the measured and the predicted retention times for PAHs in both one and two variable modeling. The ANN model, strongly affected by the number of input experiments, was shown to be less effective for one variable used, but quite successful when two input variables were used. All PAHs, including difficult to separate peak pairs (benzo(k)fluoranthene/benzo(b)fluoranthene and indeno(1,2,3-c,d)pyrene/dibenzo(a,h)anthracene), were separated in a standard (5% phenyl-95% dimethylpolysiloxane) capillary column at an optimum temperature ramp of 8.0 degrees C/min and final hold temperature in the range of 260-320 degrees C.     

Determination of polycyclic aromatic hydrocarbons in water by solid-phase microextraction-gas chromatography-mass spectrometry

A solid-phase microextraction (SPME)-gas chromatography (GC)-mass spectrometry (MS) analytical method for the simultaneous separation and determination of 16 polycyclic aromatic hydrocarbons (PAHs) from aqueous samples has been developed, based on the sorption of target analytes on a selectively sorptive fibre and subsequent desorption of analytes directly into GC-MS. The influence of various parameters on PAH extraction efficiency by SPME was thoroughly studied. Results show that the fibre exposure time and the use of agitation during exposure are critical in enhancing SPME performance. The presence of colloidal organic matter (as simulated by humic acid) in water samples is shown to significantly reduce the extraction efficiency, suggesting that SPME primarily extracts the truly dissolved compounds. This offers the significant advantage of allowing the differentiation between freely available dissolved compounds and those associated with humic material and potentially biologically unavailable. The method showed good linearity up to 10 μg/l. The reproducibility of the measurements expressed as relative standard deviation (R.S.D.) was generally <20%. The method developed was then applied to extract PAHs from sediment porewater samples collected from the Mersey Estuary, UK. Total PAH concentrations in porewater were found to vary between 95 and 742 ng/l with two to four ring PAHs predominating. Results suggest that SPME has the potential to accurately determine the dissolved concentrations of PAHs in sediment porewater.     

干洗织物中氯代烃溶剂残留的气相-质谱测定

 采用固相微萃取和气 质联用技术(GC MS)对干洗衣物中氯代烯烃的残留和释放进行了分析测定。干洗过程使用的有害物质包括四氯乙烯(PCE)、三氯乙烯(TCE)及少量的三氯乙烷,这些挥发性有机物已列入许多国家和地区优先控制的污染物指标。该方法参照欧洲生态纺织品标准100对目标化合物的限量控制,以加标的标准贴衬为样品基质,将样品浸渍在含5%(体积分数)甲醇的饱和NaCl溶液中,于(40±1)℃水浴中超声处理10min后,再将样液用100μmPDMS固相微萃取纤维顶空提取,然后进行GC MS测定。     

The development of solid-surface fluorescence characterization of polycyclic aromatic hydrocarbons for potential screening tests in environmental samples

This paper presents the characterization of polycyclic aromatic hydrocarbons (PAHs) in solid-surface fluorescence as the first step for obtaining new optical sensors for PAHs screening. The fluorescence properties of the EPA-PAHs (naphthalene, acenaphthene, acenaphthylene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo[a]anthracene, benzo[k]fluoranthene, benzo[b]fluoranthene, benzo[a]pyrene, indeno [1,2,3-cd]pyrene, benzo[g,h,i]perylene and dibenzo[a,h]anthracene) on five types of solid-surfaces were evaluated. The experimental variables (pH and percentage of organic solvent in samples) were studied, obtaining different possibilities for making individual sensors for some of these PAHs and the best conditions for developing sensors for PAH screening were also studied.     

Use of solid-phase microextraction/gas chromatography-electron capture detection for the determination of energetic chemicals in marine samples

Gas chromatography with electron capture detection (GC-ECD) is a highly explosive-sensitive analytical technique. However, its application to the analysis of sediment extracts is hampered by the presence of numerous endogenous interferences. In the present study, solid-phase microextraction (SPME) was used both as a purification technique for sediment extracts and as an extraction technique for water samples prior to analysis by GC-ECD. SPME/GC-ECD coupling was optimized and applied to the trace analysis of nine explosives including nitroaromatics and RDX in real seawater and marine sediment samples. Addition of a high concentration of salt (30%, w/v) in the aqueous medium and use of a carbowax/divinylbenzene (CW/DVB) coating led to optimal extraction efficiencies. Method detection limits (MDLs) ranged from 0.05 to 0.81 microg/L in water and from 1 to 9 microg/kg in dry sediment. Except for RDX, spike recoveries in seawater were satisfactory (89-147%) when samples were fortified at 2 microg/L of each analyte. Spike recoveries from dry sediment fortified at 10 microg/kg of each analyte gave lower recoveries but these could also be due to degradation in the matrix. With a smaller volume of aqueous sample required compared to solid-phase extraction (SPE), SPME is an attractive method for the analysis of limited volumes of sediment pore-water. Moreover, the use of SPME eliminated interferences present in sediment extracts thus allowing the detection of the target analytes that were otherwise difficult to detect by direct injection.     

Determination of nanogram/kilogram levels of polycyclic aromatic hydrocarbons in foods by HPLC with fluorescence detection

Methodology was developed for the determination of eight polycyclic aromatic hydrocarbons (PAH) in five food categories including meat/fish, dried dairy products, cereals, leafy vegetables and vegetable/marine oils. The eight PAH were fluoranthene, benzo[a]anthracene, benzo[k]fluoranthene, benzo[b]fluoranthene, benzo[a]pyrene, 7,12-dimethylbenzo[a]anthracene, dibenzo[ah]anthracene and dibenzo[ai]pyrene. Samples were digested with alcoholic KOH followed by partitioning into solvents such as cyclohexane or isooctane. Lipids and other interferences were removed by solvent partitioning with dimethylformamide or dimethylsulfoxide/water. Additional cleanup involving column chromatography on silica gel, Florisil or Sephadex LH-20 was employed as required. Reversed-phase chromatography with gradient elution and fluorescence detection was employed for the determinations. Confirmation was carried out by GC-MS/SIM. Detection limits ranged from 2-90 ng/kg depending on the PAH and food analyzed. Results of a small survey indicated that the meat/fish category had the highest levels (low microgram/kg, on average) of the foods studied.     

Determination of polycyclic aromatic hydrocarbons (PAHs) in particulate matter collected with low volume samplers

The determination of polycyclic aromatic hydrocarbons (PAHs) contained in samples of particulate matter (PM), collected with low volume pumps, were carried out with an high sensitivity method that comes from several revisions of a previous method. The present work describes how, by using programmable temperature vaporization (PTV) and a mass selective detector with inert ionic source for the GC-MS analysis and the modifications of microwave-assisted extraction (MAE), the sensitivity of the method can be increased.The PAHs chosen for testing the method are: benzo[a]anthracene (BaA), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), indeno[1,2,3-cd]pyrene (Ip) and dibenzo[a,h]anthracene (DbA). They, in fact, belong to that group of substances that are the most harmful for human health for their carcinogenicity.PAHs recoveries for spiked standard solutions at different concentrations were between 95 and 100% with relative standard deviation ranging from 1 to 3%. The revised method was validated using a 1649a urban dust standard reference material (SRM). The results obtained were in good agreement with certified values. The high sensitivity of the method allows to carry out analyses using only a half of the sampled filter (usually 47 mm diameter membranes). In this way, the other half can be used for the characterization of the other components of PM (heavy metals, organic carbon, ions, etc). The last step has been constituted by application of the optimized method on real samples collected in two cities located in Southern Italy (Bari and Taranto).     

Gas chromatographic-mass spectrometric determination of polycyclic aromatic hydrocarbons formed during the pyrolysis of phenylalanine

The formation of polycyclic aromatic hydrocarbons (PAHs) during pyrolysis process of phenylalanine had been studied. Ten PAHs, including fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[k]fluoranthene, benzo[e]pyrene, and benzo[a]pyrene were analyzed by gas chromatography-mass spectrometry using selective ion monitoring mode. This technique offers the capability to analyze trace amounts of PAHs in phenylalanine pyrolyzates. The pyrolysis was carried out in a micro-furnace with quartz furnace liner. The injection was conducted with glass pelletizer syringe to avoid metal contamination. Qualitative results were obtained at 900 degrees C and quantitative analysis of 10 PAHs was done for 700 and 900 degrees C.