Determination of atmospheric nitrobenzanthrones by high-performance liquid chromatography with chemiluminescence detection.

A method using high-performance liquid chromatography with chemiluminescence detection was developed for analyzing mutagenic nitrobenzanthrone (NBA) isomers in airborne particulates. The method was a modification of our previously described method for analyzing nitropolycyclic aromatic hydrocarbons (NPAHs). The pretreatment and reducing conditions for 1-, 2-, 3- and 10-NBAs were the same as those for NPAHs. In order to separate these NBA isomers, we used a polymeric-type ODS column (Cosmosil 5C-18MS); a mixture of 40% acetonitrile and 60% 10 mM imidazole-HClO4 buffer was employed as the mobile phase at a flow rate of 1 mL/min. The isomers of 1-, 2-, 3- and 10-NBA were determined in chemiluminescence with linear calibration graphs from 0.1 to 4 pmol, from 200 to 4000 pmol, from 1 to 50 pmol and from 10 to 400 pmol, respectively. The detection limits (S/N = 3) of 1-, 2-, 3- and 10-NBA isomers were 0.02 pmol, 35 pmol, 0.3 pmol and 3 pmol, respectively. The method was used to analyze airborne particulates at a heavy traffic site in Kanazawa. 2- and 3-NBAs were detected in the extracts of the particulates, while 1-NBA and 10-NBA were not detected. The atmospheric concentrations of 2- and 3-NBAs were 1.83 pmol/m3 and 24.7 fmol/m3, respectively.     

Pollution characteristics of ambient PM2.5-bound PAHs and NPAHs in a typical winter time period in Taiyuan

The pollution characteristics of ambient fine particulate matter（PM2.5） containing polycyclic aromatic hydrocarbons（PAHs） and nitrated PAHs（NPAHs） in samples collected during a typical winter time period in Taiyuan of China were investigated.The obtained results revealed that the mean mass concentrations of PM2.5,SPAHs（sum of 16 PAHs） and SNPAHs（sum of 3 NPAHs） on PM2.5were161.4 mg/m3,119.8 ng/m3and 0.446 ng/m3,respectively.Diagnostic ratios of PAHs and NPAHs implied that coal consumption might be the main source of the PM2.5pollution.The measured PM2.5mass concentrations,BaP equivalent toxicity（28.632 ng/m3） and individual carcinogenicity index（3.14 10 5） were much higher than those of the recommended safety standards.     

Determination of 1,3-, 1,6-, 1,8-dinitropyrene and 1-nitropyrene in airborne particulate by column liquid chromatography with electrochemical detection

Nitrated polycyclic aromatic hydrocarbons (NPAHs) in airborne particulate were determined by column liquid chromatography with electrochemical detection. NPAHs were extracted ultrasonically prior to being injected into the separation system. A reversed-phase C18 column was used to separate the NPAHs with an aqueous eluent containing acetonitrile and sodium monochloroacetate as buffer. Calibration graphs were linear with very good correlation coefficients (r>0.999) and the detection limits were ca. 20 pg for all analytes. The proposed method provides a relatively simple and convenient procedure for determining the NPAHs in airborne particulate.     

色谱质谱中的选择离子监测方式定量分析柴油机排气微粒中多环芳香烃

使用色谱－质谱联用中的选择离子监测的方法选择性地检测柴油机排气中的多环芳香烃,采用１４种多环芳香烃混合标准样品绘制校正曲线,以外标法对柴油机排气微粒中的ＰＡＨｓ进行定量分析。实验结果表明,该方法能够减少其它类有机成份的干扰,快速、准确地测量柴油机排气微粒中多环芳香烃的含量,且重复性较好,相对标准偏差低于 １２％（ｎ＝６）,检出限为３．５～７．０ｐｇ／ｍ３,样品的回收率为７９％～８９％,方法用于柴油机排气微粒中多环芳香烃排放量的测定取得了满意的效果。     

Determination of hydroxylated polycyclic aromatic hydrocarbons in airborne particulates by high-performance liquid chromatography with fluorescence detection.

This paper describes a highly sensitive and selective method for the determination of hydroxylated polycyclic aromatic hydrocarbons (PAHs-OH) in airborne particulates. PAHs-OH were extracted from airborne particulates with ethanol by ultrasonication. The extractant was further cleaned up by solid phase extraction (SPE) with an aminopropylsilica cartridge, and subsequently analyzed by reversed-phase high-performance liquid chromatography with fluorescence detection. 2-Hydroxy-1-acetonaphthone was used as an internal standard. By the proposed method, 2-hydroxyfluorene and 1-hydroxypyrene were identified in airborne particulates and their concentrations were determined for the first time.     

Solid-phase extraction with C30 bonded silica for analysis of polycyclic aromatic hydrocarbons in airborne particulate matters by gas chromatography-mass spectrometry

A solid-phase extraction (SPE) method using triacontyl bonded silica (C30) as sorbent was developed for the determination of 16 US Environmental Protection Agency polycyclic aromatic hydrocarbons (PAHs) in airborne particulate matters quantitatively by gas chromatography-mass spectrometry (GC-MS). Optimization experiments were conducted using spiked standard aqueous solution of PAHs and real airborne particulates samples aiming to obtain highest SPE recoveries and extraction efficiency. Factors were studied in SPE procedures including the concentration of organic modifier, flow rate of sample loading and elution solvents. The ultrasonication time and solvents were also investigated. Recoveries were in the range of 68-107% for standard PAHs aqueous solution and 61-116% for real spiked sample. Limits of detection (LODs) and limits of quantification (LOQs) with standard solution were in the range of 0.0070-0.21 microgL(-1) and 0.022-0.67 microgL(-1), respectively. The optimized method was successfully applied to the determination of 16 PAHs in real airborne particulate matters.     

Determination of airborne polycyclic aromatic hydrocarbons at an airport by gas chromatography-mass spectrometry and evaluation of occupational exposure

The aim of this study was to determine airborne polycyclic aromatic hydrocarbons (PAHs) and biphenyl at an airport by gas chromatography-mass spectrometry and to evaluate occupational exposure by environmental monitoring. A total of 12 samplings were carried out in three areas: (1) a handling area where baggage was unloaded manually from vehicles onto conveyor belts (n=5); (2) the runway with plane and motor vehicle traffic (n=5) and (3) a departure lounge (n=2). PAHs levels were in most cases low. The higher levels found refer to naphthalene (130-13,050 ng/m3) and to its methyl-substitutes 2-methylnaphthalene (64-28,500 ng/m3) and 1-methylnaphthalene (24-35,300 ng/m3), and biphenyl (24-1610 ng/m3). A method was used to quantify twenty-four airborne PAHs, and biphenyl, and to detect a variety of other chemical compounds by means of the deconvolution program AMDIS. After sampling air on quartz filter and PUF and XAD-2 sorbents; extraction with dichloromethane, and concentration and purification on silica cartridges, analyses were carried out by gas chromatography-ion trap mass spectrometry. We used 20 deuterated PAHs to quantify both the 24 native PAHs and biphenyl. The native substances had been subdivided into small groups and in this way, their volatility was adequately reflected by the D-PAH present in each group. The limit of detection was 0.1 ng/m3 for all the PAHs, and a linear range of at least about three-fold the maximum level studied (naphthalene) was obtained both for D-PAHs and the native PAHs. A good recovery pattern was obtained for D-PAHs on quartz filters, PUF and XAD-2.     

Trace determination of nitrated polycyclic aromatic hydrocarbons using liquid chromatography with on-line electrochemical reduction and fluorescence detection

An efficient clean-up procedure coupled with a high performance liquid chromatography (HPLC) with on-line electrochemical (EC) reduction and fluorescence detection (FLD) was developed to quantify nitrated polycyclic aromatic hydrocarbons (NPAHs) in the airborne particulate. In this process, NPAHs were extracted ultrasonically followed by analysis by using a reversed phase column with an aqueous eluent containing 70% aqueous acetonitrile and sodium monocholoroacetate as a buffer solution. The extraction efficiencies were above 83% for 1-nitropyrene and 1,3-dinitropyrene (1,3-DNP) 1,6-DNP, and 1,8-DNP, and calibration graphs were linear with very good correlation coefficients (r>0.999) and the detection limits were in the range of 1.0-2.2 pg for dinitropyrenes and nitropyrene. The proposed method provides a relatively simple and convenient procedure for determining the NPAHs samples in airborne particulate.     

Improvement of an automatic HPLC system for nitropolycyclic aromatic hydrocarbons: removal of an interfering peak and increase in the number of analytes.

An automatic HPLC system for analyzing nitropolycyclic aromatic hydrocarbons (NPAHs, nitroarenes) in airborne particulates was previously described (Anal. Chim. Acta, 2001, 445, 20). Some problems with this system were that it generated a peak originating from an ascorbic acid solution that elutes at a retention time close to that of 1,6-dinitropyrene (DNP), and that it was able to analyze only 1,3-, 1,6-, 1,8-DNPs and 1-nitropyrene (I-NP). Here, we describe an improved system that effectively removes the interfering peak by introducing an ODS column just after the pump for the ascorbic acid solution, and which is capable of analyzing several additional compounds (2-, 4-NPs, 2-nitrofluorene. 6-nitrochrysene, 7-nitrobenz[a]anthracene, 3-nitroperylene and 6-nitrobenzo[a]pyrene etc.). The improved sensitivities were achieved by concentrating the compounds in a benzene-ethanol extract from airborne particulates, by increasing the loading time of the sample solution from 20 to 38 min, and by increasing the flow rate of an ascorbic acid solution from 1.3 to 1.8 mL/min.     

Determination of nitro-polycyclic aromatic hydrocarbons in atmospheric aerosols using HPLC fluorescence with a post-column derivatisation technique

The objective of this study was to develop an efficient and sensitive analytical protocol for the determination of nitrated polycyclic aromatic hydrocarbons (NPAHs) in aerosol samples. The separation of 16 NPAH (mono-and dinitro-PAH) was achieved by reversed-phase high-performance liquid chromatography (HPLC) followed by on-line reduction of the NPAHs to their corresponding amino polycyclic aromatic hydrocarbons (APAHs) and quantification by fluorescence detection. The main factors affecting the on-line reduction efficiency, such as the flow rate, the temperature, the position and packing of the reduction column were evaluated and optimised. The optimal conditions obtained were: packing of the reduction column with Pt-Al(2)O(3); a reduction column oven temperature of 90 degrees C; a flow rate of 0.8 mL min(-1). The resulting detection limits of the method ranged between 0.06 (2 NN) and 1.25 microg L(-1) (1.8 DNN), with an uncertainty of about 6%. The lifetime of the reduction column was identical to that of a typical analytical column. This analytical method was applied to particulate matter samples collected during December 2005 and August 2006 in Strasbourg (Alsace, eastern France). The NPAH concentrations observed for this urban site showed that the compounds are more abundant during winter (average of 534 pg m(-3)) than during summer (average of 118 pg m(-3)). 1-Nitropyrene was the predominant NPAH species, independent of season.     

Highly sensitive automatic analysis of polycyclic aromatic hydrocarbons in indoor and outdoor air

A method for the quantitation of polycyclic aromatic hydrocarbons (PAHs) in indoor and outdoor air by high-performance liquid chromatography (HPLC) with a spectrofluorometric detection and programmed excitation and emission wavelength pairs is proposed. The mobile phase is a linear gradient of methanol-water. The relative standard deviations (n = 5) are in the range 0.38-1.7% at concentration levels of 0.69-11.40 ng ml(-1). The determination limits (S N = 10 ) are 0.5-15.9 pg. The proposed method was successfully applied to quantitate 12 PAHs in gas phase and particulates in indoor and outdoor air. The recoveries of PAHs from gas phase and particulates were 95.7-117.5 and 94.8-112.4%, respectively. This highly sensitive automatic HPLC analysis for PAHs both in gas phase and particulates can be applied to indoor and outdoor survey.     

Thermodynamic and kinetic characterization of a bridged-ethylene hybrid C18 stationary phase

In this study, a series of polycyclic aromatic hydrocarbons (PAHs) and nitrogen-containing polycyclic aromatic hydrocarbons (NPAHs) is separated on a hybrid stationary phase using methanol and acetonitrile mobile phases. Temperature is varied from 283 to 313 K in order to determine thermodynamic and kinetic parameters of the separation. Thermodynamic behavior is characterized by the retention factor and associated changes in molar enthalpy, whereas kinetic behavior is characterized by the rate constants and associated activation energies. In this study, the retention factors for the NPAHs are smaller than those for the parent PAHs in methanol, while they are more similar to the parent PAHs in acetonitrile. The changes in molar enthalpy are very similar for all solutes, yet are more negative in acetonitrile than in methanol. The rate constants for the NPAHs are smaller than those for their parent PAHs in both mobile phases. Moreover, the rate constants in acetonitrile are one to four orders of magnitude smaller than those in methanol. Based on these thermodynamic and kinetic results, the hybrid stationary phase is compared to traditional silica stationary phases. In addition, the relative contributions from the partition and adsorption mechanisms are discussed.     

A novel approach for simultaneous determination of polycyclic aromatic hydrocarbons by Shpol'skii non-linear variable-angle synchronous fluorescence spectrometry

A new method of combining low-temperature Shpol'skii effect with non-linear variable-angle synchronous fluorescence spectrometry (L-NLVASFS) has been proposed to increase spectral resolution. This coupled method was applied successfully to the simultaneous identification and quantification of some polycyclic aromatic hydrocarbons (PAHs) in mixtures, which cannot be determined by non-linear variable-angle synchronous fluorescence spectrometry at room-temperature (R-NLVASFS). The usefulness of this method is demonstrated by the analyses of synthetic mixtures and several real samples of airborne particulates.     

北京地区大气颗粒物中不同功能区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年四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。两个功能区的PAHs总质量浓度分布趋势均为：冬季>秋季>春季>夏季；不同环数PAHs在不同粒径颗粒物中的分配比例比较显示，粗颗粒物中2 环或3环PAHs的分配比例比其在高环PAHs的比例要大。     

Thermodynamic and kinetic characterization of nitrogen-containing polycyclic aromatic hydrocarbons in reversed-phase liquid chromatography

A series of five nitrogen-containing polycyclic aromatic hydrocarbons (NPAHs) was studied on polymeric octadecylsilica using methanol and acetonitrile as the mobile phase. The thermodynamic and kinetic behavior was examined as a function of ring number, annelation structure, and position of the nitrogen atom. The retention factors for the NPAHs are smaller than those for the parent PAHs in methanol, while the converse is true in acetonitrile. The changes in molar enthalpy are relatively comparable in both mobile phases with 1-aminopyrene having values of -5.0 +/- 0.2 kcal/mol in methanol and -6.3 +/- 0.7 kcal/mol in acetonitrile (1 cal = 4.184 J). However, the rate constants from mobile to stationary phase (k(sm)) and from stationary to mobile phase (k(ms)) demonstrate large differences as a function of mobile phase. For example, the rate constants k(ms) for 1-aminopyrene and 4-azapyrene are 675 and 62 s(-1), respectively, in methanol at 303 K. In contrast, the same solutes demonstrate rate constants of 3.47 and 3.9 x 10(-3) s(-1), respectively, in acetonitrile. The activation energies for transfer from mobile phase to transition state (deltaE(double dagger(m)) and from stationary phase to transition state (deltaE(double dagger(s)) also differ as a function of mobile phase. For example, the activation energies deltaE(double dagger(s)), for 1-aminopyrene are 21 and approximately 0 kcal/mol, whereas those for 4-azapyrene are 19 and 23 kcal/mol, in methanol and acetonitrile, respectively. Based on these thermodynamic and kinetic results, the relative contributions from the partition and adsorption mechanisms are discussed.     

Simultaneous analysis of oxygenated and nitrated polycyclic aromatic hydrocarbons on standard reference material 1649a (urban dust) and on natural ambient air samples by gas chromatography-mass spectrometry with negative ion chemical ionisation

This study deals with the development of a routine analytical method using gas chromatography-mass spectrometry with negative ion chemical ionisation (GC/NICI-MS) for the determination of 17 nitrated polycyclic aromatic hydrocarbons (NPAHs) and 9 oxygenated polycyclic aromatic hydrocarbons (OPAHs) present at low concentrations in the atmosphere. This method includes a liquid chromatography purification procedure on solid-phase extraction (SPE) cartridge. Application of this analytical procedure has been performed on standard reference material (SRM 1649a: urban dust), giving results in good agreement with the few data available in the literature. The analytical method was also applied on ambient air samples (on both gas and particulate phases) from the French POVA program (POllution des Vallées Alpines). NPAHs concentrations observed for a rural site during the Winter period are about 0.2-100.0pgm(-3) in the particulate phase and about 0.0-20.0pgm(-3) in the gas phase. OPAHs present concentrations 10-100 times higher (0.1-2.0ngm(-3) and 0.0-1.4ngm(-3) for the particulate and the gas phases, respectively). These preliminary results show a good correlation between the characteristics of the sampling site and the compound origins (primary or secondary).     

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。     

Quantification of polycyclic aromatic hydrocarbons (PAHs) in human hair by HPLC with fluorescence detection: a biological monitoring method to evaluate the exposure to PAHs

A high-performance liquid chromatographic (HPLC) method with fluorescence detection was developed for the quantification of polycyclic aromatic hydrocarbons (PAHs) in human hair. Fifteen kinds of PAHs classified as priority pollutants by the US EPA were quantified with four perdeuterated PAHs as internal standards. After 50 mg hair samples were washed with n-hexane to remove external contamination of PAHs, the samples were digested in 2.5 M sodium hydroxide. The digests were extracted with n-hexane and then analyzed by HPLC. Eleven kinds of PAHs were identified in hair samples of 20 subjects, and 10 kinds of PAHs were eventually quantified using the internal standards. For anthracene, chrysene and benzo[k]fluoranthene, significant differences were observed between smokers and non-smokers. Although benzo[b]fluoranthene, dibenz[a,h]anthracene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene were observed in the particulates of indoor and outdoor air, they were not detected in all hair samples. The analysis of PAHs in human hair should be useful as a new biomarker to evaluate the exposure to PAHs.     

二级热脱附-气相色谱-质谱联用测定大气可吸入颗粒物中的16种多环芳烃

建立了二级热脱附-气相色谱-质谱联用技术测定大气可吸入颗粒物PM10中16种多环芳烃的分析方法。对二级热脱附和色谱-质谱条件进行了优化。实验结果表明,方法的检出限为0.14～0.42 ng/m3,平均加标回收率为52.7%～97.9%,相对标准偏差(RSD)为8.0%～18.4%。与传统方法相比,该方法的样品前处理时间短、有机溶剂的使用量少,是对人体及环境友善的检测技术。该方法已应用于32份实际大气颗粒物样品的分析。     

A review of techniques for the determination of polycyclic aromatic hydrocarbons in air

We provide an extensive review of the common methodologies employed in the analysis of airborne polycyclic aromatic hydrocarbons (PAHs). The review focuses on gas-chromatography-based approaches, in the light of their universal application with excellent separation, resolution, and sensitivity.We first describe collection methods for airborne PAHs in the gas and particle phases. We then evaluate the efficiency of extraction techniques employed for separating target PAHs from sampling media, using conventional solvent-based and emerging thermal-desorption approaches.We also describe commonly employed analytical methods with respect to their applicability to PAHs in gas and particle phases, collected from diverse environmental settings. As an essential part of basic quality assurance, we examine each method with special emphasis on key parameters (e.g., limit of detection and reproducibility).Finally, we address the likely directions of methodological developments, their limitations, and the future prospects for PAH analysis.