Polycyclic aromatic hydrocarbons (PAHs) in a coal tar standard reference material—SRM 1597a updated

SRM 1597 Complex Mixture of Polycyclic Aromatic Hydrocarbons from Coal Tar, originally issued in 1987, was recently reanalyzed and reissued as SRM 1597a with 34 certified, 46 reference, and 12 information concentrations (as mass fractions) for polycyclic aromatic hydrocarbons (PAHs) and polycyclic aromatic sulfur heterocycles (PASHs) including methyl-substituted PAHs and PASHs. The certified and reference concentrations (as mass fractions) were based on results of analyses of the coal tar material using multiple analytical techniques including gas chromatography/mass spectrometry on four different stationary phases and reversed-phase liquid chromatography. SRM 1597a is currently the most extensively characterized SRM for PAHs and PASHs.     

Analysis of aromatic compounds in gasoline with flow-switching comprehensive two-dimensional gas chromatography

A comprehensive two-dimensional gas chromatography (GC x GC) instrument has been created by coupling a flow-switching modulator and a standard gas chromatograph. The instrument was used to characterize the aromatic composition of gasoline. The high-resolution separation produced by flow-switching GC x GC allowed gasoline aromatics to be fully resolved from saturated components. The aromatic compounds were further separated into groups having the same carbon number. A standard gasoline sample was analyzed to evaluate the quantitative accuracy and precision of this technique. The data show that flow-switching GC x GC produces results that are comparable to gas chromatography-mass spectrometry (GC-MS) and thermal modulation GC x GC. The simple, low-cost, and robust nature of flow-switching GC x GC makes it an ideal technique for the routine analysis of aromatic compounds in gasoline.     

Thermal desorption gas chromatography–mass spectrometry as an enhanced method for the quantification of polycyclic aromatic hydrocarbons from ambient air particulate matter

Polycyclic aromatic hydrocarbons (PAHs) from ambient air particulate matter (PM) were analysed by a two-step thermal desorption (TD) injection system integrated to a gas chromatograph–mass spectrometer (GC/MS). The operational variables of the TD method were optimised and the analytical expanded uncertainties were calculated to vary from 8% to 16% over the operative concentration range (40–4000 pg). The performance of the TD method was validated by the analysis of a standard reference material and by comparison of PAH concentrations in PM samples to those obtained by a conventional liquid extraction (LE) method. The TD method reported lower uncertainties than the LE method for the analysis of similar concentrations in air. The TD method also showed advantages for shorter sampling times in comparison to 24 h for source apportionment applications and for reducing losses of more reactive compounds such as benzo[a]pyrene.     

Polycyclic aromatic hydrocarbons in C8 isomer aromatic feed: analysis by GC, GC/MS, and GC/FTIR techniques

Polycyclic aromatic hydrocarbons (PAHs), apart from their carcinogenic and mutagenic nature, create many problems in the petrochemical industry due to their tendency toward carbonization. Compounds in C8 aromatic isomer feed are analyzed by means of sample concentration, followed by separation of individual compounds by gas chromatography on a stainless steel OV-101 phase capillary column and identification by gas chromatography/mass spectrometry and gas chromatography/Fourier transform infrared spectroscopy. Various compounds belonging to different classes (mainly monocyclic, dicyclic, and tricyclic aromatics), oxygenated aromatics, and aliphatic saturates are quantified in the concentrated hydrocarbon residue of C8 isomer feed. Both unsubstituted and alkyl substituted ring type compounds are present. Concentrations obtained for PAH compounds in the C8 isomer feed range from 0.2 to 0.42 micrograms/mL.     

The Application of Active Biomonitoring with the Use of Mosses to Identify Polycyclic Aromatic Hydrocarbons in an Atmospheric Aerosol

The use of biological indicators of environmental quality is an alternative method of monitoring ecosystem pollution. Various groups of contaminants, including organic ones, can be measured in environmental samples. Polycyclic aromatic hydrocarbons (PAHs) have not yet been determined by the moss bag technique. This technique uses several moss species simultaneously in urban areas to select the best biomonitoring of these compounds, which are dangerous to humans and the environment. In this research, a gas chromatography coupled with mass spectrometry was used for the determination of selected PAHs in three species of mosses: Pleurozium schreberi, Sphagnum fallax and Dicranum polysetum (active biomonitoring) and for comparison using an air filter reference method for atmospheric aerosol monitoring. The chlorophyll fluorescence of photosystem II (PSII) was also measured to assess changes in moss viability during the study. As a result of the study, the selective accumulation of selected PAHs by mosses was found, with Pleurozium schreberi being the best bioindicator—9 out of 13 PAHs compounds were determined in this species. The photosynthetic yield of photosystem (II) decreased by 81% during the exposure time. The relationship between PAHs concentrations in mosses and the total suspended particles (TSP) on the filter indicated the possibility of using this bioindicator to trace PAHs in urban areas and to apply the moss bag technique as a method supporting classical instrumental air monitoring.     

气相色谱质谱法测定化妆品中9种多环芳烃

建立了气相色谱质谱法测定化妆品中9种多环芳烃的分析方法。化妆品中的萘、苯并[a]蒽、、苯并[b]荧蒽、苯并[j]荧蒽、苯并[k]荧蒽、苯并[e]芘、苯并[a]芘、二苯并[a,h]蒽等9种多环芳烃用甲醇超声提取后,用环己烷液-液萃取后浓缩,经硅胶-中性氧化铝柱净化后,采用气相色谱-质谱测定。多环芳烃浓度在0.05～2 mg/L范围内,质量浓度与其峰面积呈良好的线性关系。在低、中、高3个添加水平下,9种多环芳烃化合物的平均回收率为81.6%～100.2%,相对标准偏差为1.3%～5.8%。方法可用于化妆品中多环芳烃的检测。     

Analysis of BTEX, PAHs and metals in the oilfield produced water in the State of Sergipe, Brazil

During oil and gas exploitation, large amounts of produced water are generated. This water has to be analyzed with relation to the chemical composition to deduce the environmental impact of its discharge after a treatment process. Therefore, a study was carried out to evaluate preliminarily the BTEX (benzene, toluene, ethylbenzene and xylenes), polycyclic aromatic hydrocarbons (PAHs) and metals contents in produced water samples taken from effluents of the Bonsucesso treatment plant located in the city of Carmópolis, the most important oil and gas producer in the State of Sergipe, North-east of Brazil. Three methods were optimized to determine the target compounds. Polycyclic aromatic hydrocarbons were determined by gas chromatography with mass spectrometric detection (GC/MS), volatile aromatic hydrocarbons (BTEX) by gas chromatography with photoionization detector (GC/PID) and metals were analyzed by flame atomic absorption spectrometry (FAAS). The results showed that concentrations of the target compounds in these samples ranged from 96.7 to 1397 μg L^− 1 for BTEX, from 0.9 to 10.3 μg L^− 1 for PAHs and from 0.003 to 4540 mg L^− 1 for metals.     

自动化质谱图解卷积和鉴定系统用于鉴定含痕量杂原子的石油馏分（英文）

Here we present a simple yet effective gas chromatography-mass spectrometry (GC-MS) identification approach for the detection of heteroatom-containing compounds (HACCs) in petroleum fractions. The MS/AMDIS (Automated Mass Spectral Deconvolution and Identification System) program was used to identify parts per million (ppm) HACC concentrations in petroleum fractions in place of traditional techniques (extraction and standard injection). Polycyclic aromatic sulfur heterocycles (S-PAHs) were used as model compounds to confirm the validity of the AMDIS identifiers, which were compared with extracted results using the off-line X-calibur software. AMDIS was able to identify ppm concentrations of S-PAHs in oil condensate. There was good agreement between experimental and AMDIS identification results for S-PAHs in oil condensate. AMDIS was also used to detect nitrogen-containing compounds (NCCs) and alkylphenols in oil condensate. Our results confirmed the presence of 2-methylbenzothiazole, carbazole, and 2,4-ditertbutyl phenol. In a crude oil sample, AMDIS identification of m/z=191 biomarkers was consistent with empirical results. Therefore, AMDIS can help to reduce the number of experimental steps in identification protocols.     

Trueness, precision, and detectability for sampling and analysis of organic species in airborne particulate matter

Recovery, precision, limits of detection and quantitation, blank levels, calibration linearity, and agreement with certified reference materials were determined for two classes of organic components of airborne particulate matter, polycyclic aromatic hydrocarbons and hopanes, using typical sampling and gas chromatography/mass spectrometry analysis methods. These determinations were based on initial method proficiency tests and on-going internal quality control procedures. Recoveries generally ranged from 75% to 85% for all target analytes and collocated sample precision estimates were generally better than 20% for polycyclic aromatic hydrocarbons and better than 25% for hopanes. Results indicated substantial differences in data quality between the polycyclic aromatic hydrocarbons and hopanes. Polycyclic aromatic hydrocarbons demonstrated better collocated precision, lower method detection limits, lower blank levels, and better agreement with certified reference materials than the hopanes. The most serious area of concern was the disagreement between measured and expected values in the standard reference material for hopanes. With this exception, good data quality was demonstrated for all target analytes on all other data quality indicators.