Determination of chlorinated polycyclic aromatic hydrocarbons in water by solid‐phase extraction coupled with gas chromatography and mass spectrometry

Given the potential risks of chlorinated polycyclic aromatic hydrocarbons, the analysis of their presence in water is very urgent. We have developed a novel procedure for determining chlorinated polycyclic aromatic hydrocarbons in water based on solid‐phase extraction coupled with gas chromatography and mass spectrometry. The extraction parameters of solid‐phase extraction were optimized in detail. Under the optimal conditions, the proposed method showed wide linear ranges (1.0–1000 ng/L) with correlation coefficients ranging from 0.9952 to 0.9998. The limits of detection and the limits of quantification were in the range of 0.015–0.591 and 0.045–1.502 ng/L, respectively. Recoveries ranged from 82.5 to 102.6% with relative standard deviations below 9.2%. The obtained method was applied successfully to the determination of chlorinated polycyclic aromatic hydrocarbons in real water samples. Most of the chlorinated polycyclic aromatic hydrocarbons were detected and 1‐monochloropyrene was predominant in the studied water samples. This is the first report of chlorinated polycyclic aromatic hydrocarbons in water samples in China. The toxic equivalency quotients of chlorinated polycyclic aromatic hydrocarbons in the studied tap water were 9.95 ng the toxic equivalency quotient m^?3. 9,10‐Dichloroanthracene and 1‐monochloropyrene accounted for the majority of the total toxic equivalency quotients of chlorinated polycyclic aromatic hydrocarbons in tap water.     

Passive sampling for volatile organic compounds (VOCs) in air at environmentally relevant concentration levels

A sensitive and reliable method is described for the determination of aromatic and chlorinated hydrocarbons (benzene, toluene, o-, m-, p-xylene, trichloromethane, trichloroethane, trichloroethene and tetrachloroethene) in indoor and outdoor air at environmental concentration levels. The procedure can be easily extended to other VOCs. Using passive samplers the VOCs have been adsorbed onto charcoal during a four-week sampling period and subsequently desorbed with carbon disulfide. After injection with a cold split-splitless multi-injector the VOCs have been separated by capillary gas chromatography. Quantification has been achieved using an electron capture detector (ECD) and a flame ionization detector (FID) switched in series. A limit of about 1 g/m³ for aromatic hydrocarbons and of about 0.01 g/m³ for chlorinated hydrocarbons has been obtained. The procedure has been successfully applied in the framework of a field study to measure indoor and outdoor air concentrations in Essen and Borken, two differently polluted areas of Northrhine-Westphalia.     

On the presence of PCDD/Fs and other chlorinated hydrocarbons in the second generation of the European Reference Soil Set--the EUROSOILS

The second generation of the European Reference Soil-Set, the so-called EUROSOILS, has been introduced recently. The presence of organic micro-pollutants in this new type of reference materials has already been studied for polycyclic aromatic hydrocarbons, triazines, phenylureas and other pesticides. The already large amount of data concerning the level of different contaminants, the elemental composition and matrix properties is completed by a survey by means of GC/MS on the polychlorinated dibenzodioxins/furans (PCDD/Fs) and other chlorinated hydrocarbons. Higher concentrations for 4,4'-DDT in EUROSOIL 2 (10.57 +/- 0.02 ng/g), for dieldrin in EUROSOIL 3 (8.85 +/- 0.87 ng/g) and for heptachlor-epoxide in EUROSOIL 4 (5.86 +/- 0.16 ng/g) could be detected. Sum concentrations for PCDD/Fs were 15.02 ng/kg (EUROSOIL 1), 214.29 ng/kg (EUROSOIL 2), 873.32 ng/kg (EUROSOIL 3), 54.47 ng/kg (EUROSOIL 4) and 119.61 ng/kg (EUROSOIL 5).     

热脱附-气相色谱-质谱法测定环境空气中67种挥发性有机物

采用热脱附-气相色谱-质谱法,建立了同时分析环境空气中67种挥发性有机物的分析方法。对比了5种不同填充材料不锈钢吸附管对78种挥发性有机物的吸附能力。填充材料为Tenax TA和Carbograph 1TD的混合填料吸附管对分析物的捕集效果最好,在30 mL/min高纯He气持续吹脱45 min的情况下,未发生穿透（即穿透率小于10%）的化合物达67种,分析物的种类包括芳香烃、脂肪烃、卤代烃和含氧挥发性有机物等。优化了使用该吸附管测定67种目标物时的热脱附条件。在5~100 ng范围内,目标化合物的色谱响应值与其量间具有良好的线性关系,其相关系数（r）均在1.0000~0.9977之间。方法检出限为0.3~2.4 ng,以采样体积1 L计算,检出限为0.3~2.4 μg/m³。加标量为20 ng时,7次重复实验目标化合物回收率均在81.6%~114.9%之间,目标化合物的相对标准偏差为1.2%~10.1%。采用该方法对某车厢内空气进行了检测,检出了包括酯类、卤代烷烃、卤代烯烃以及芳香族化合物在内的19种目标化合物,其范围为1.1~84.1 μg/m³。该方法准确、可靠、灵敏度高,实现了对环境空气中67种目标污染物的准确定量。     

Determination of selected human pharmaceutical compounds in effluent and surface water samples by high-performance liquid chromatography-electrospray tandem mass spectrometry

A simple method is presented for the analysis of 13 pharmaceutical and pharmaceutical metabolite compounds in sewage effluents and surface waters. The pharmaceutical compounds were extracted using a genetic solid-phase extraction (SPE) procedure using Phenomenex Strata X as a stationary phase. Extracts were quantitatively analysed by four separate reversed-phase high-performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-ESI-MS/MS) techniques and quantified by comparison with an internal standard ([13C]-phenacetin). Recoveries and limits of detection (LOD) for sulfamethoxazole (120%, 50 ng l(-1)), acetyl-sulfamethoxazole (56%, 50 ng l(-1)), trimethoprim (123%, 10 ng l(-1)), erythromycin (73%, 10 ng l(-1)), paracetamol (75%, 50 ng l(-1)), ibuprofen (117%, 20 ng l(-1)), clofibric acid (83%, 50 ng l(-1)), mefenamic acid (24%, 50 ng l(-1)), diclofenac (62%, 20 ng l(-1)), propranolol (45%, 10 ng l(-1)), dextropropoxyphene (63%, 20 ng l(-1)) and tamoxifen (42%, 10 ng l(-1)) were all acceptable. The recovery of lofepramine (4%) was too low to be of use in a monitoring programme. Application of the method to samples collected from UK sewage effluents and surface waters showed detectable concentrations of mefenamic acid, diclofenac, propranolol, erythromycin, trimethoprim and acetyl-sulfamethoxazole in both matrices. Ibuprofen and dextropropoxyphene were detected in sewage effluents alone. All other pharmaceutical compounds were below the methods limits of detection.     

Molecular modelling of host-guest interactions for mass sensitive chemical sensors

Paracyclophanes are effective coatings for mass sensitive chemical sensors. The enzyme analogue recognition can preferably be used to detect aromatic and halogenated hydrocarbons. Molecular modelling by the MM3 force field allows the prediction of an efficient analyte inclusion. Besides the necessary steric complementarity it could be shown that the interaction between the methyl groups of aromatic guests (e.g. toluene) and the aromatic walls of the host is essential for hostguest complexation. These phenomena get more pronounced if bicyclic cyclophanes are applied and these sensitive materials enable the detection of only a few ppm of toluene with SAW devices. Furtheron, the electron-rich diphenylether moieties of these hosts guarantee interactions with electron-deficiency analytes such as chlorinated hydrocarbons with a selectivity superior to that of the monocyclic materials.Dedicated to Professor Dr. Dr. h.c. mult. J.F.K. Huber on the occasion of his 70th birthday     

Determination of Trace Amounts of Organic Pollutants in the Yellow River by Capillary Column Gas Chromatography-Mass Spectrometry

Abstract

The trace organic pollutants in the Yellow River enriched by a solvent extraction method were pre-separated into four different fractions of fatty hydrocarbons, polycyclic aromatic hydrocarbons, polar compounds and organic acids and were analyzed by the use of combined capillary column gas chromatography-mass spectrometry. Using the combined techniques of relative retention value, mass spectra and mass chromatogram, more than 60 organic pollutants were identified, among which 16 fatty hydrocarbons and 6 polycyclic aromatic hydrocarbons which were quantitatively analyzed. The concentration range of fatty hydrocarbon was 5–800 ng/l, and that of polycyclic aromatic hydrocarbon was 0-90ng/l.     

Evaluation of tetraglyme for the enrichment and analysis of volatile organic compounds in air

A recently developed method for the sampling and analysis of volatile organic compounds in air has been evaluated. The system is based on the enrichment of analytes in tetraethylene glycol dimethyl ether or tetraglyme, a water-soluble organic liquid. The subsequent analysis consists of dispersion of a sample aliquot in water followed by purge-and-trap and gas chromatographic separation. Physico-chemical data were investigated for 10 volatile organic compounds, providing information on the possibilities and limitations of the tetraglyme method. The target analytes included chlorinated alkanes and alkenes, and monocyclic aromatic hydrocarbons. Air/tetraglyme partition coefficients Kat were determined over an environmental relevant temperature range of 2-25 degrees C to evaluate sorption efficiencies and estimate breakthrough volumes at the sampling stage. At 2 degrees C breakthrough volumes (allowing 5% of breakthrough) ranged from 5.8 (1,1-dichloroethane) to 312 l (1,1,2-trichloroethane) for 20 ml of tetraglyme. With regard to the desorption stage, the effect of tetraglyme on the air/water partition of organic compounds was investigated through the measurement of air/tetraglyme-water partition coefficients Kat-w for 2-31% (v/v) tetraglyme in water. Finally a clean-up procedure for tetraglyme was evaluated. Analysis of a blank tetraglyme-water (17:83, v:v) mixture by gas chromatography-flame ionization detection/mass spectrometry showed minor background signals. None of the target compounds were detected.     

Investigation on Distribution and Risk Assessment of Volatile Organic Compounds in Surface Water,Sediment, and Soil in a Chemical Industrial Park and Adjacent Area

The occurrences, distributions, and risks of 55 target volatile organic compounds (VOCs) in water, sediment, sludge, and soil samples taken from a chemical industrial park and the adjacent area were investigated in this study. The Σ₅₅-VOCs concentrations in the water, sediment, sludge, and soil samples were 1.22–5449.21 μg L⁻¹, ND–52.20 ng g⁻¹, 21.53 ng g⁻¹, and ND–11.58 ng g⁻¹, respectively. The main products in this park are medicines, pesticides, and novel materials. As for the species of VOCs, aromatic hydrocarbons were the dominant VOCs in the soil samples, whereas halogenated aliphatic hydrocarbons were the dominant VOCs in the water samples. The VOCs concentrations in water samples collected at different locations varied by 1–3 orders of magnitude, and the average concentration in river water inside the park was obviously higher than that in river water outside the park. However, the risk quotients for most of the VOCs indicated a low risk to the relevant, sensitive aquatic organisms in the river water. The average VOCs concentration in soil from the park was slightly higher than that from the adjacent area. This result showed that the chemical industrial park had a limited impact on the surrounding soil, while the use of pesticides, incomplete combustion of coal and biomass, and automobile exhaust emissions are all potential sources of the VOCs in the environmental soil. The results of this study could be used to evaluate the effects of VOCs emitted from chemical production and transportation in the park on the surrounding environment.     

Adsorption/Thermal Desorption with Tenax-GC for the Collection and Analysis of Polycyclic Aromatic Hydrocarbons and Chlorinated Compounds

A system for the determination of polycyclic aromatic hydrocarbons(PAHs) and chlorinated compounds in air by means of adsorption/thermal desorption(ATD) with small bed volume (0.1 g) Tenax cartridges, followed by cryogenic trap in a U-shaped stainless steel tube with liquid nitrogen as an appropriate concentration method prior to capillary gas chromatography is described. Recoveries were determined for the complete ATD method. Desorption recoveries near 100% were found for a variety of chlorinated compounds and polycyclic aromatic hydrocarbons.     

On the presence of PCDD/Fs and other chlorinated hydrocarbons in the second generation of the European Reference Soil Set – the EUROSOILS

The second generation of the European Reference Soil-Set, the so-called EUROSOILS, has been introduced recently. The presence of organic micro-pollutants in this new type of reference materials has already been studied for polycyclic aromatic hydrocarbons, triazines, phenylureas and other pesticides. The already large amount of data concerning the level of different contaminants, the elemental composition and matrix properties is completed by a survey by means of GC/MS on the polychlorinated dibenzodioxins/furans (PCDD/Fs) and other chlorinated hydrocarbons. Higher concentrations for ¶4,4′-DDT in EUROSOIL 2 (10.57 ± 0.02 ng/g), for dieldrin in EUROSOIL 3 (8.85 ± 0.87 ng/g) and for heptachlor-epoxide in EUROSOIL 4 (5.86 ± 0.16 ng/g) could be detected. Sum concentrations for PCDD/Fs were 15.02 ng/kg (EUROSOIL 1), 214.29 ng/kg (EUROSOIL 2), 873.32 ng/kg (EUROSOIL3), 54.47 ng/kg (EUROSOIL 4) and 119.61 ng/kg (EUROSOIL 5).     

Determination of polycyclic aromatic hydrocarbons in drinking and surface waters from Galicia (N.W. Spain) by constant-wavelength synchronous spectrofluorimetry

We describe a fast, new method for determination of the joint concentration of the six polycyclic aromatic hydrocarbons (PAHs), designated by current legislation as indicators of the quality of drinking waters and surface waters intended for the abstraction of drinking waters. The limit of detection of the new method was 6 ng l(-1), its limit of quantification 20 ng l(-1), its precision (CV%) 2.48 and its recovery 94.05%. Its speed allowed rapid PAH screening of 404 samples of surface and drinking water from Galicia (N.W. Spain).     

Real-time monitoring of monochlorinated benzene and polychlorinated biphenyls in the gas phase with on-line detection: High chemical selectivity of resonance-enhanced two-photon ionization.

The development of molecular spectroscopy has enabled us to select chlorinated aromatic hydrocarbons very rapidly. In particular, the laser ionization TOFMS (time-of-flight mass spectrometry) method is expected to be useful as an on-line, selective, and sensitive method. In the present work, real-time laser ionization TOFMS measurements were carried out on gaseous chlorinated aromatic hydrocarbons. The laser ionization method used resonance-enhanced two-photon ionization with the direct introduction of gas into the vacuum chamber. This method for analyzing aromatic hydrocarbons was developed using a pulsed supersonic molecular beam method. In the context of developing a highly selective and sensitive method, excitation of monochlorinated benzene at lambda = 263.07 nm was found to be effective in the wavelength region from 263 nm to 265 nm. Also the excitation of polychlorinated biphenyls at lambda = 266 nm was found to be substantially more effective than at lambda = 280, 300 or 320 nm. The achievable sensitivity for real-time (1 min) measurements using the laser ionization TOFMS technique was found to be in the ppbV range.     

抚顺乙烯焦油的精馏分离与气相色谱-质谱联用分析

为避免乙烯焦油作为燃料粗放燃烧造成的芳烃资源浪费与环境污染,我们以抚顺乙烯焦油为原料,常压蒸馏切割<280 ℃馏分,然后采用填充柱进行常压精馏,将<280 ℃馏分切割为12个馏分段(40~150 ℃、150~170 ℃、170~180 ℃、180~190 ℃、190~200 ℃、200~210 ℃、210~220 ℃、220~230 ℃、230~240 ℃、240~250 ℃、250~260 ℃和260~280 ℃),以达到对抚顺乙烯焦油的精馏分离。 以HP-5MS毛细管填充柱为色谱柱,对得到的12个馏分段进行气相色谱-质谱联用定性、定量分析,为乙烯焦油中芳烃的提取和乙烯焦油深加工利用提供具有指导价值的分析数据。 结果显示,抚顺乙烯焦油<280 ℃馏分占焦油总量的52.2%,主要由1~4芳香烃组成。 单环、三环和四环芳烃质量分数较少,单环芳烃主要为苯的衍生物,质量分数为5.8%,3环和4环芳烃占2.998%,主要为苊、芴、蒽、菲、芘等。 抚顺乙烯焦油中质量分数最多的双环芳烃为萘,其次为β-甲基萘、α-甲基萘和1,4-二氢萘,它们在各馏分段的最高分布分别为41.152%、16.729%、12.089%和9.046%。 由此乙烯焦油可作为提取高附加值芳环类精细化工产品的良好原料。     

喷气燃料裂解产物中芳烃的全二维气相色谱-质谱分析

采用全二维气相色谱-质谱联用仪(GC×GC-MS),通过优化程序升温和调制周期,建立了喷气燃料裂解产物中芳烃的定性定量分析方法。该方法对多环芳烃(PAH)同分异构体具有良好的分离能力。利用MS检测器谱库检索结果、芳烃标准品及相关的文献报道,对喷气燃料裂解产物中常见的单环芳烃、二环芳烃、三环芳烃及四环芳烃等共27种芳烃进行了准确定性,并利用外标GC×GC-FID法对其进行定量。定量结果表明,芳烃含量均随着裂解产气率的增加而增大,当裂解产气率达到22%时,二环芳烃开始产生,且其含量随着裂解产气率的增加呈指数形式增加。该方法与传统的气相色谱-质谱相比,具有更好的分离及定性能力,可应用于复杂样品的分离及其定性定量分析。     

Determination of polycyclic aromatic hydrocarbons in waste water by off-line coupling of solid-phase microextraction with column liquid chromatography

A new method for the determination of polycyclic aromatic hydrocarbons (PAHs) in waste water using solvent-free solid-phase microextraction (SPME) is described. The PAHs are extracted with a 100 microm polydimethylsiloxane (PDMS) fiber, desorbed in 40 microl acetonitrile and measured with LC and fluorescence detection. The detection limits of this very simple method under the given conditions (extraction from 5 ml sample, extraction time 1 h) are in the range of 1-6 ng l(-1). The standard deviations (n = 6) at a concentration level of 0.8 microg l(-1) are between 1.8 and 14.4%. The procedure was used for the determination of PAHs in contaminated water samples.     

Compound-specific stable isotope analysis of organic contaminants in natural environments: a critical review of the state of the art,prospects, and future challenges

Compound-specific stable isotope analysis (CSIA) using gas chromatography-isotope ratio mass spectrometry (GC/IRMS) has developed into a mature analytical method in many application areas over the last decade. This is in particular true for carbon isotope analysis, whereas measurements of the other elements amenable to CSIA (hydrogen, nitrogen, oxygen) are much less routine. In environmental sciences, successful applications to date include (i) the allocation of contaminant sources on a local, regional, and global scale, (ii) the identification and quantification of (bio)transformation reactions on scales ranging from batch experiments to contaminated field sites, and (iii) the characterization of elementary reaction mechanisms that govern product formation. These three application areas are discussed in detail. The investigated spectrum of compounds comprises mainly n-alkanes, monoaromatics such as benzene and toluene, methyl tert-butyl ether (MTBE), polycyclic aromatic hydrocarbons (PAHs), and chlorinated hydrocarbons such as tetrachloromethane, trichloroethylene, and polychlorinated biphenyls (PCBs). Future research directions are primarily set by the state of the art in analytical instrumentation and method development. Approaches to utilize HPLC separation in CSIA, the enhancement of sensitivity of CSIA to allow field investigations in the µg L^–1 range, and the development of methods for CSIA of other elements are reviewed. Furthermore, an alternative scheme to evaluate isotope data is outlined that would enable estimates of position-specific kinetic isotope effects and, thus, allow one to extract mechanistic chemical and biochemical information.Abbreviations BTEX benzene, toluene, ethylbenzene, xylenes - MTBE methyl tert-butyl ether - PAHs polycyclic aromatic hydrocarbons - VOCs volatile compounds - PCBs polychlorinated biphenyls - CSIA compound-specific (stable) isotope (ratio) analysis - GC-IRMS, GC/IRMS or GCIRMS gas chromatography-isotope ratio mass spectrometry - GC-C-IRMS, GC/C/IRMS or GCC-IRMS gas chromatography-combustion-isotope ratio mass spectrometry - irmGC/MS isotope ratio monitoring gas chromatograph-mass spectrometry - GC/P/IRMS gas chromatography-pyrolysis-isotope ratio mass spectrometry (used for D/H) - KIE kinetic isotope effect - PSIA position-specific isotope analysis (for intramolecular isotope distribution) - SNIF-NMR site-specific natural isotopic fractionation by nuclear magnetic resonance spectroscopy     

Determination of Henry''s law coefficients by combination of the equilibrium partitioning in closed systems and solid-phase microextraction techniques

This paper describes the determination of Henry's law coefficients by means of the EPICS (equilibrium partitioning in closed systems) technique in combination with SPME (solid-phase microextraction). The use of solid-phase microextraction-sampling allowed us to extend the possibilities of the equilibrium partitioning in closed systems technique with respect to the range of Henry's law coefficients which can be measured. Whereas the equilibrium partitioning in closed systems technique is limited to determine air–water equilibrium partitioning of volatile compounds with Henry's law coefficients of at least 0.06 (dimensionless), the current method allowed to measure coefficients between 0.0023 and 13.5. In this way Henry's law coefficients of 20 compounds, being in a range covering five orders of magnitude, were measured with relative standard deviations between 1.0 and 19.8% (mean standard deviation: 5.7%; median of standard deviations: 4.8%, n=99). Several types of compounds were examined i.e. aliphatic hydrocarbons, monocyclic and polycyclic aromatic hydrocarbons, chlorinated and fluorinated compounds, ethers and esters, biphenyl and N-containing compounds, including compounds for which availability of experimental Henry's law coefficients is limited. Measurement of the equilibrium partitioning in the 2 to 25°C range allowed to establish relations of Henry's law coefficient as a function of temperature.     

Pyrrole-based conductive polymer as the solid-phase extraction medium for the preconcentration of environmental pollutants in water samples followed by gas chromatography with flame ionization and mass spectrometry detection

A pyrrole-based polymer was synthesized and applied as a new sorbent for solid-phase extraction (SPE) of some environmental pollutants from water samples. Polypyrrole (PPy) was synthesized by chemical oxidation of the monomer in nonaqueous solution. SPE of selected phenols, pesticides, and polyaromatic hydrocarbons (PAHs) from aqueous samples were performed using 200 mg PPy. The determination was subsequently carried out by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The polymer showed much higher recoveries for aromatic compounds than aliphatics. Preconcentration of sample volumes up 11 led to acceptable recoveries for aromatic and other tested polar compounds. The R.S.D. for a river water sample spiked with phenols, pesticides and PAHs at sub-ppb level was lower than 10% (n = 3) and limits of detection for these compounds were between 15 and 120 ng l(-1).     

High-energy irradiation of chlorinated hydrocarbons

The Lawrence Livermore National Laboratory (LLNL) and the Idaho National Engineering Laboratory (INEL) are jointly investigating the decomposition of chlorinated hydrocarbons using bremsstrahlung radiation produced by electron accelerators and gamma photons from spent reactor fuel. Experimental results demonstrate an exponential type decay of concentration with dose for volatile organic compounds (VOCs) in ground water and for both polychlorinated biphenyls (PCBs) and insecticides in organic solutions. Experiments were performed at several photon energies and dose rates with various initial concentrations. Mass balance analysis suggests complete mineralization of VOCs in ground water and indicates significant degradation of PCBs and insecticides to VOC type compounds in organic solutions.Work performed under the auspices of the U.S. Department of Energy, DOE Contract Nos. W-7405-ENG-48 and DE-AC07-76IDO1570.