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This research aimed to study the migration of mineral oil aromatic hydrocarbons (MOAH) from primary carton packages to dry foods, using 16 aromatic hydrocarbons as model substances, covering a wide range of molecular masses and chemical structures. Migration experiments were performed using modified polyphenylene oxide as a food simulant and couscous and polenta as dry foods. The migration tests were carried out to simulate storage at room temperature for long periods and in hot food containers as the worst scenario. Multivariate analysis algorithms were applied to correlate and group the migration of model substances, and a partial least squares regression (PLSR) model was built to predict the worst-case migration. The results showed strong correlations in the migration patterns of the model substances, based on their volatility, food matrix, migration time and temperature. Different behaviour between the migration of the most volatile and the heaviest model substances was observed.

This article studies the migration of MOAH from hot melt adhesives used in multilayer laminates into food simulants. First, the initial concentration of a group of compounds selected as MOAH markers in several adhesives was determined by headspace solid phase microextraction coupled to gas chromatography mass spectrometry (HS-SPME-GC-MS), using the previously optimised method. Then, the migration of the MOAH fraction and MOAH markers from the laminates was studied. The MOAH fraction was analysed by gas chromatography with flame ionisation detection (GC-FID), and the MOAH markers were analysed by HS-SPME-GC-MS. Twelve MOAH markers were detected, and their initial concentrations were between 0.46 and 33.8 μg g-1. Only eight were identified after migration, ranging between 0.62 and 21.33 μg dm-2, with a migration percentage of 12–75%. The fraction of MOAH that migrated eluted mainly in the C16-C25 range and reached concentrations of 19.65 μg dm-2 from the laminate.

The aim of this work was to select and identify the best markers of aromatic hydrocarbon mineral oil (MOAH) in food packaging. For this purpose, a series of mineral oils was initially analysed. Polycyclic Aromatic Hydrocarbons (PAHs) and the alkylated isomers of Methylnaphthalene (MNS), Diisopropylnaphtalene (DIPNs), Dibenzothiophenes (DBTS), Methyldibenzothiophene (MDBTs), Dimethyldibenzothiophenes (DMDBTs) and Benzonaphthiophenes (BNTS) were then explored. Their presence was confirmed by direct analysis of several mineral oils by Atmospheric Solids Analysis Probe Quadrupole-Time of Flight Mass Spectrometry (ASAP-QTOF-MS). Atmospheric Pressure Gas Chromatography Quadrupole-Time of Flight Mass Spectrometry (APGC-QTOF-MS) was used to confirm the markers in different samples of oils, recycled PET (rPET), recycled cardboard and packaging of couscous and semolina to confirm the contamination. 27 markers were found in the mineral oil samples, 22 of them in rPET, 8 in recycled board and no MOAH were found in packaging of couscous and semolina.

Polycyclic aromatic hydrocarbons (PAHs), tobacco-specific nitrosamines (TSNAs) and aromatic amines are carcinogens present in cigarette smoke. These compounds are distributed in the human body and they could be transferred to the foetus during the pregnancy. Placenta is the main barrier to these toxic compounds and its study is the objective of this work. A method based on solid-phase extraction (SPE) with ultra-performance liquid chromatography−tandem quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS) has been examined and optimized for the analysis of 9 target analytes (4 tobacco-specific nitrosamines and some of their metabolites, 3 aromatic amines, nicotine and cotinine) in 26 placenta samples from smoking and non-smoking women. Limits of detection (LODs) were in the range of 3–27 ng/g of placenta. Nicotine, cotinine, N -nitrosoanatabine (NAT) and 4-(methylnitrosamino)-1- (3-pyridyl)-1-butanone (NNK) metabolite, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) were detected in the placenta samples of smoking woman. Nicotine was detected in 3 out of 8 placentas from smoking women, always below the limit of quantification (88 ng/g). This could be expected, as the half-life of nicotine in the body is limited to about 0.5–3 h. Cotinine, the main metabolite from nicotine, was detected in all placentas from smoking women at concentrations between 17.2 and 61.8 ng/g, reaching the highest values for those women that smoked the highest number of cigarettes. NAT and NNAL were detected in all placentas from smoking women, always below the limit of quantification (40 ng/g and 33 ng/g respectively).

The seeds and leaves of coriander plant are commonly used spices around the world. Since antiquity, coriander has been used in folk medicine, and more recently, parts of the plant, extracts/oils, and other pure compounds extracted from the plant have started to be used in the cosmetic and food industries as aromas and flavoring substances. Coriander is cultivated worldwide and the crop is influenced by factors such as the cultivar, soil nutrients, or agronomical practices. Coriander has vast array of biological properties such as antioxidant, anti-inflammatory, analgesic, and antimicrobial. In recent research, coriander oils or extracts have exhibited a broad spectrum of antimicrobial activity, being active against Gram-positive and Gram-negative bacteria, yeasts, molds, and parasites. This chapter highlights the coriander antimicrobial activity and possible mechanisms of action in microbial cells and discusses the possibilities for coriander use, mainly within the food industry as a food preservative.

En este trabajo presentamos un método sencillo y rápido para confirmar la contaminación por aceites minerales (MOH) de distintos tipos de muestras mediante extracción por SPE y determinación por Cromatografía de Gases con Detector de masas.

The use of packaging materials at very high temperatures, such as in-pack cooking, could lead to the formation of odorous compounds and also to the transference of migrants to food. In this work, the effect of high temperature or microwave cooking has been studied for 2 different cooking bags. The study was performed by gas-chromatography coupled to mass spectrometry and to olfactometric detection (GC-MS-O). The results showed that the bags heated in a conventional oven had a higher effect on the increment of odor impact compounds from the packaging than those heated in microwaves. Aldehydes and ketones were the major responsible for the odors detected in the olfactometry. Migration experiments to different food simulants (ethanol 10%, vegetable oil and ethanol 95%) and food samples (chicken) were also performed. In migration to food simulants, migrants were only detected in ethanol 10 %: 1-nonanol was detected below the specific migration limit established in the European Regulations and nonanal and decanal were below 10 ng/g. In migration to chicken a total of 27 compounds, mostly aldehydes, were transferred to it under the worst case migration conditions.

Esta investigación explora la utilización de determinados marcadores para detectar, identificar y cuantificar los hidrocarburos aromáticos procedentes de aceites minerales en diferentes materiales, empleando Cromatografía de Gases a Presión Atmósferica acoplada a un Cuadrupolo con un Espectometro de Masas de Tiempo de Vuelo (APGC-MS/Q-TOF).

Se han producido cambios sociales, valorándose más el tiempo y la comodidad y esto ha llevado consigo a producirse también cambios en la forma de cocinar. El uso de envases que te permitan cocinar el alimento directamente en su interior está aumentando considerablemente ya que es una forma rápida, sana y limpia, lo que ha llevado a un aumento en la demanda de este tipo de envases. Debido a esta demanda, es interesante estudiar los posibles riesgos que puede conllevar su uso. El alimento está en constante interacción con el envase y su entorno, dando lugar a una posible migración. Además, al aplicar altas temperaturas durante un tiempo determinado, ya sea en el horno o en el microondas, esta migración puede verse acelerada, dando lugar a compuestos capaces de producir alteraciones organolépticas, al ser sustancias sensorialmente activas; o ser sustancias tóxicas, llegando a hacerlos no aptos para el consumo. Este proyecto tiene como objetivo principal evaluar este tipo de envases tanto desde el punto de vista del material como de las interacciones que se pueden producir con su uso. Así se van a identificar los compuestos capaces de migrar desde los envases de cocinado al alimento. Para llevar a cabo este objetivo se identificarán los compuestos presentes en el material, se compararán esos compuestos en diferentes materiales, y, por último, se evaluará la influencia del tipo de tratamiento térmico, reproduciendo las condiciones de cocinado recomendadas por el fabricante. Una vez identificados los compuestos en el material, se hará un estudio de migración utilizando simulantes alimentarios para determinar qué compuestos tienen capacidad para migrar al alimento. Para la identificación de todos los compuestos se utilizará la cromatografía de gases con espectrómetro de masas acoplada a olfatometría. Los resultados muestran que en el material se forman numerosos compuestos volátiles, la mayoría de ellos aldehídos, que son sustancias sensorialmente activas y además, varios de ellos tienen la capacidad de migrar al alimento. Sin embargo, se ha demostrado que mediante la olfatometría se detectan una mayor cantidad de compuestos que por la espectrometría de masas. Esto quiere decir que los compuestos que migran están a baja concentración, por lo que no debería afectar a la seguridad del alimento, pero sí que son capaces de producir alteraciones organolépticas en el alimento.

La preocupación por conservar el medio ambiente ha crecido notablemente en los últimos años. Como resultado, se recicla más plástico y se le intenta dar diferentes usos, entre los que se encuentra el envasado de alimentos. Sin embargo, dicho material puede llegar a causar cambios organolépticos o transmitir sustancias que supongan un riesgo en la salud del consumidor. El objetivo del presente estudio consistió en diseñar un método de análisis para muestras de PET, uno de los plásticos más utilizados en envasado de alimentos, e identificar los compuestos con mayor impacto en muestras elaboradas con distinta proporción de reciclado. Para ello se utilizó cromatografía de gases acoplada a espectrometría de masas y a olfatometría, y se optimizó el tratamiento de muestra en función de la temperatura. Se evaluaron las modificaciones que se producen entre botellas y granzas con diferente proporción de reciclado, y se estudiaron posibles migraciones de compuestos mediante la utilización de simulantes alimentarios. Los resultados mostraron un aumento de compuestos, volátiles y no volátiles, en muestras que contenían una mayor proporción de PET reciclado. Muchos de estos compuestos fueron aldehídos, compuestos capaces de producir variaciones en las propiedades sensoriales de los alimentos. Sin embargo, su migración fue escasa, por lo que no debería afectar a la seguridad del alimento.

Inks are commonly used in food packaging materials and therefore, migration of ink components to food must be studied. Migration from different multilayer materials containing inks to 2 food simulants (ethanol 95% and to Tenax®) was performed, the effect of ink transference and how it was affected by the presence of lacquers in the material was studied. A total of 17 migrants coming from inks due to a set-off phenomena were found in migration from multilayer material [ink/PET/aluminum/polyethylene]. The number of migrants decreased dramatically when a lacquer was added [lacquer/ink/PET/aluminum/polyethylene] and especially when ink was placed under a PET layer [lacquer/PET/ink/aluminum/polyethylene]. Some new migrants appear by the reaction between ink and lacquer. In material [ink/paper/OPP/Al/PE], when a lacquer was added some migrants decreased but other migrants present both in lacquer and ink increased.

An automated method for analyzing free non-cholesterol sterols in human serum using online solid phase extraction-liquid chromatography-mass spectrometry is proposed herein. The method allows the determination of three phytosterols (sitosterol, stigmasterol and campesterol) and two cholesterol precursors (desmosterol and lanosterol). The analysis of sterols in human serum is critical in the study of cholesterol-related disorders, such as inherited familial hypercholesterolemias. Special effort was made to isolate the analytes from the serum lipoproteins, their natural conveyance through the bloodstream. The sample treatment consisted of a Bligh-Dyer extraction followed by dilution of the extract. This treatment allowed the sample to be injected into the online system and ensured the correct detection of the analytes, while avoiding the matrix effects commonly related to serum samples. The analytical performance showed linear ranges that covered two orders of magnitude, with correlation coefficients above 0.99. Limits of detection and quantification ranged from 0.2 ng/mL to 13 ng/mL and from 1.0 ng/mL to 43 ng/mL, respectively. Recovery when spiking serum with a half or a tenth of the average concentration reported in human serum ranged from 99% to 111% and from 102% to 120%, respectively. Intra-day precision and inter-day precision were below 20%.

The potential use of cholesterol esterases was tested to avoid alkaline hydrolysis for cleavage of plasma esterified oxysterols. The enzymatic hydrolysis was optimized by testing two sources of enzyme— Pseudomonas and bovine pancreas, presence of surfactants, incubation time and amount of enzyme. Free forms of 4β-, 7-, 24-, 25- and 27-hydroxycholesterol (HC) as well 7-ketocholesterol (7-KC) were analyzed by liquid chromatography and mass-spectrometry using the deuterated internal standard, 25-HC(d6). Enzymatic hydrolysis was more effective using the Pseudomonas enzyme and in presence of surfactants. Compared to alkaline hydrolysis, it generated a cleaner chromatographic baseline and better recovery of the internal standard. Oxysterols were assayed with detection limits between 7 and 31 pg/mL. Interassay coefficients of variation were lower than 10% and extraction recovery efficiencies, higher than 90%. The procedure was used to characterize plasma levels of Cyp7b1- deficient rat, where it showed increased plasma levels of 7, 24 and 25-HC. Due to the low volume of sample required, it may be used in other animal models, particularly rodents, as well as in pediatric samples where sample amount is always a problem. Thus, the proposed new method offers mild enzymatic processing that greatly facilitates oxysterol determinations to delineate their role in physiopathology.

Printing inks are commonly used in multilayer plastics materials used for food packaging, and compounds present in inks can migrate to the food either by diffusion through the multilayers or because of set-off phenomena. To avoid this problem, the right design of the packaging is crucial. This paper studies the safety by design of multilayer materials. First, the migration from four different multilayers manufactured using polyethylene terephthalate (PET), aluminium (Al) and polyethylene (PE) was determined. The structural differences among materials such as the presence of inks or lacquer coatings as well as the differences in layers position allowed the study of a safety-by-design approach. Sixty-nine different compounds were detected and identified; 49 of them were not included in the positive list of Regulation EU/10/2011 or in Swiss legislation and 15 belong to Cramer class III, which means that they have a theoretical high toxicity. Some of the compounds related to ink composition were pyrene, a compound commercially used to make dyes and dye precursors and the antioxidant Irganox 1300. The application of external lacquers decreased the concentration of some migrants but also brought the potential for new migrants coming from its composition. A final risk assessment of the material allowed evaluating food safety for different food simulants and confirm it.

The analysis of sterols in biological fluids allows the clinical study of cholesterol related diseases. This research is focused on reducing the sample processing time of the determination of free and bonded sterols in human serum. Ten sterols were studied: cholesterol precursors (desmosterol, lanosterol, and cholestanol); phytosterols (stigmasterol, campesterol, sitosterol, and sitostanol) and oxysterols (7-α-hydroxy-4-cholesten-3-one, 24-hydroxycholesterol, and 27-hydroxycholesterol). Ultrasound assistance was used to diminish the reaction time during the alkaline hydrolysis for determining total sterols. Different retention mechanisms of solid-phase extraction were compared, two reversed-phase sorbents DSC-18 and polymeric Oasis-HLB and a novel zirconia-coated silica phase. DSC-18 and zirconia-coated silica were the most suitable sorbents to analyze these metabolites. The resulting extracts were analyzed by liquid chromatography coupled to mass spectrometry. The analytical parameters were determined and better values were observed with DSC-18 cartridges for most sterols. LOQ were in the low ng/mL level. Recoveries were in the range 85-99%. Average intermediate precision was 15%. Accuracy for both cartridges was more than 92%. Zirconia-coated silica showed better performance for the oxysterols, with recoveries around 90%. The procedure allows the determination of free and bonded sterol precursors, phytosterols, and oxysterols in human serum.

Within the family of polycyclic aromatic hydrocarbons (PAHs), nitrated derivatives are of particular interest in environmental science because they have well-known carcinogenic and mutagenic effects. They are in fact more toxic than their parent PAHs. One valuable diagnosis of atmospheric pollution can be obtained using biomonitors such as mosses. These biomonitors can provide information about air pollution over long periods of time in wilderness areas. Thus, they can serve as monitors of the atmospheric transport of pollutants. In this study, atmospheric pressure gas chromatography coupled to a quadrupole hyphenated to a time of flight mass spectrometer (APGC–MS/Q-TOF) has been examined for the identification of target analytes (15 PAHs and 8 NPAHs) for subsequent use in the analysis of mosses. Working ranges in low μg g −1 concentration levels were obtained with most correlation coefficients higher than 0.999. All LODs were in the 0.007–0.035 μg g −1 range and higher LODs (0.035 μg g −1 ) were obtained for the less volatile PAHs with higher mass and retention times: benzo(g,h,i)perylene, dibenz(a,h)anthracene and indeno(1,2,3-c,d)pyrene. These LODs are of importance for the intended use, biomonitoring, especially taking into account that NPAHs are commonly found at very low concentration levels. Recoveries from mosses ranged from 75 to 98%. Intraday and interday precision ranged from 1.8 to 11.1% RSD and from 2.4 to 16.7% RSD, respectively. Very low concentrations of NPAHs were found in mosses compared to those of PAHs. All these data were used for pattern recognition of the pollutant source. The results are shown and discussed.

This paper describes a new, fully automated on-line method combining restricted access material (RAM) extraction and ultra high-performance liquid chromatography (UHPLC) with mass spectrometric (MS) detection for determining congeners of bile acids (BAs) in human serum. In this method, low-pressure RAM and high-pressure UHPLC-MS are hyphenated by using a 2.5-mL loop-type interface. The compatibility problem between the large volume (1.2mL) of strong solvent (methanol) used for RAM elution and the need for a weak solvent in UHPLC injection has been addressed by using an auxiliary pre-column cross-flow of 0.1% aqueous formic acid. In this way, the complete 2.5mL loop volume can be injected into the UHPLC system, thereby maximizing sensitivity while maintaining good chromatographic performance. The optimised method allows the simultaneous analysis of 13 bile acids in a single run, including glycine- and taurine-conjugated bile acids, cholic acid (CA), deoxycholic acid (DCA), chenodeoxycholic acid (CDCA), ursodeoxycholic acid (UDCA), and litocholic acid. The complete analysis of a 100-microL single serum sample is performed in 30 min, providing detection limits in the pg range (corresponding with clinically relevant concentration levels) for all of the analytes except lithocholic acid, intra-day precision values (%R.S.D.) below 4% (except ursodeoxycholic acid) and inter-day precision lower than 15% (except ursodeoxycholic, glycoursodeoxycholic acid (GUDCA) and lithocholic acid).

The air quality in the Aragón valley, in the central Pyrenees, has been assessed by evaluation of lichen biodiversity and mapped by elaboration of the Index of Air Purity (IAP) based on observations of the presence and abundance of eight kinds of lichen with different sensitivity to air pollution. The IAP values obtained have been compared with quantitative analytical measures of 16 PAHs in the lichen Evernia prunastri, because this species was associated with a wide range of traffic exposure and levels of urbanization. Analyses of PAHs were carried out by the DSASE method followed by an SPE clean-up step and GC-MS analysis. The concentration of total PAHs found in lichen samples from the Aragón valley ranged from 692 to 6420 ng g(-1) and the PAHs profile showed predominance of compounds with three aromatic rings. The influence of the road traffic in the area has been shown because values over the median concentration of PAHs (1092 ng g(-1)), percentage of combustion PAHs (50%), and equivalent toxicity (169) were found in lichens collected at places exposed to the influence of traffic. The combination of both methods suggests IAP as a general method for evaluating the air pollution referenced to PAHs because it can be correlated with the content of combustion PAHs and poor lichen biodiversity can be partly explained by the air pollution caused by specific PAHs.

A clean-up procedure based on a solid-phase extraction column was optimized for determination of polycyclic aromatic hydrocarbons (PAHs) in lichen extracts to remove co-extracted compounds from the matrix in the final extract. Several kinds of solid phases were evaluated: normal phase (-NH2 and alumina), strong anion exchange and reversed phase. The -NH2 columns were the most effective by using a packed solid bed of 500 mg. The lichen raw extract was loaded on the column previously conditioned with dichloromethane and hexane. Hexane (0.5 mL) was used as rinsing solvent, and PAHs were quantitatively eluted (80–97%) using 2 mL of hexane–dichloromethane (65–35) as eluting solvent. In these conditions, even the heaviest PAHs were quantitatively eluted. The optimized SPE method provides a short time and low-solvent-consumption sample clean-up compared with other conventional methods based on column chromatography. The analytical procedure, dynamic sonication-assisted extraction, followed by the optimized solid...

A new screening method has been explored for direct analysis of tobacco smoke biomarkers in biological matrices (i.e., saliva and urine). Single run analysis using Atmospheric pressure Solid Analysis Probe (ASAP) and high resolution mass spectrometry with quadrupole and time of flight detector has been applied directly to some biological samples (i.e., urine and saliva), providing a fast, efficient and sensitive method of identification. The method has been applied to saliva and urine samples from heavy tobacco smokers for exposure studies. Nicotine itself, nicotine metabolites (i.e., cotinine, trans-3'-hydroxycotinine, nicotine-N-glucuronide) and other related tobacco smoke toxic compounds (i.e., NNK 4-[methyl(nitroso)amino]-1-(3-pyridinyl)-1-butanone, anatabine) were found in the analyzed samples. The identification of compounds was confirmed by ultrahigh performance liquid chromatography with MS-triple quadrupole detector after sample treatment. Different temporal trends and biomarkers behavior have been found in time series related samples. Both methods are compared for screening of these biological matrices.

A fast method for the extraction of polycyclic aromatic hydrocarbons, PAHs, in lichens used as biomonitors of air pollution is optimized and further applied to real lichen samples. The method consists of using the dynamic sonication-assisted solvent extraction. The lichen sample is introduced in a cell through which the extracting solvent pass at 0.2 mL/min. Sixteen PAHs were extracted from 0.2 g of dried lichens, Xanthoria parietina, in 10 min with a total extraction volume of 2 mL of hexane. The extracted fraction, previously concentrated to 500 μL, was analyzed by GC–MS without any clean-up step following extraction. Both spiked and non-spiked native samples were used for the evaluation. The procedure compared with the static ultrasonic and Soxhlet extraction, showed high efficiency with respect to both recoveries, time and solvent consumption and for all the 16 PAHs recoveries higher than 70% were obtained. The limit of detection of the investigated PAHs was in the range of 0.021–0.032 μg/g. The linear range of the entire method was 0.115–1.805 μg/g. for all the investigated PAHs. An application of the method was demonstrated with the extraction of lichens samples collected from an urban area. Twelve out of 16 investigated PAHs were found.

A solid-phase microextraction (SPME) method has been developed for the determination of pentachlorophenol (PCP) in paper and board samples. The analytical procedure involves direct extraction of PCP from paper and board samples and determination by gas chromatography with electron capture detection (GC-ECD). Two kinds of commercially available fibres; 100 microm polydimethylsiloxane (PDMS), apolar, and 85 microm polyacrylate (PA), quite polar, were evaluated to determine the extraction efficiency of pentachlorophenol. Parameters affecting the extraction process, such as temperature and time, were studied. Moreover, time of desorption and the effect of addition of salt were also investigated. The optimized procedure was applied to the analysis of pentachlorophenol (PCP) in five samples of virgin and recycled paper and board. The PCP content was determined by GC-ECD. To evaluate the effectiveness of the proposed method, it was compared with conventional extraction method with liquid-liquid extraction and derivatization. Detection limit of 0.015 microg/g for PCP in paper was achieved with a RSD of 14%.

A new procedure for the determination of sterols in serum samples is proposed. The system consists of coating a Solid Phase Microextraction (SPME) microfiber in headspace mode with the derivatizing agent N,O-bis(trimethylsilyl)trifluoracetamide (BSTFA) and then applying this coated fiber to the simultaneous extraction and derivatization of three precursors in the cholesterol biosynthesis pathway (desmosterol, lathosterol and lanosterol) and two phytosterols (sitosterol and sitostanol) in serum samples. Optimization of the analytical procedure via the application of an experimental design, a study of matrix effects, and an analysis of serum pool samples are all described and discussed.

The sampling of volatile organic compounds emitted by a process industry has been optimised and applied in realistic conditions. Two different fractions were obtained from the emission, one liquid from the condensation of the water vapour which contains the most polar compounds and another fraction of gas, which was trapped on an active carbon filter. Both fractions have been analysed by solid phase microextraction (SPME) with a polyacrylate fibre and then GC–MS. Once the composition of the industrial emission was known, two diffferent systems have been studied for reducing the air pollution. The first one involves a washing system with water and the second one combines the washing system with a chemical oxidation using NaClO–NaOH. A pilot plant has been installed connected to the industrial chimney for the study. Reduction factors of air pollution of 70 and 90%, respectively, have been found. The analytical results as well as the technological ones are shown and discussed.

Four different waste oils have been pyrolyzed using an experimental bench scale pyrolysis unit at 600 °C under atmospheric pressure and the polyaromatic hydrocarbons (PAHs) have been analyzed in the valuable liquid fraction. After the appropriate digestion and extraction procedures, the individual PAHs were quantified in each case by HPLC–UV. Toxicity of the PAHs mixture obtained in the liquid fraction resulting from the pyrolysis of machine waste oil, automotive waste oil, hydraulic waste oil and cutting waste oil as well as the PAHs profile are compared and discussed.

Several samples taken from Duero River source in Spain have been analysed to evaluate the potential risk of uncontrolled discharges from wood industries located in the surrounding area. Toluene, dodecane, tetradecane, naphthalene, 1-tetradecene, 1-hexadecene, BHT, benzophenone, diisobutylphthalate (DiBP), dibenzofuran and fluoranthene have been selected as representative compounds from solvents and other components of varnishes or coatings, the most likely contamination origin. Solid-phase microextraction (SPME) with further GC–MS has been selected as analytical technique by both its versatility, high process speed, low cost and sensitivity. In order to reach the maximum overall performance, three fibres with different polarity: 100 μm polydimethylsiloxane (PDMS), 85 μm polyacrylate, and 65 μm Carbowax-divinylbenzene have been evaluated. In addition, and due to the high number of involved variables, a two-level full factorial experiment design has been applied for optimisation being sampling time (5–20 min), sorption temperature (room: 50 °C), desorption temperature (minimum recommended +10%, maximum recommended −10%) and salt concentration (NaCl, 0–1 M) as ionic strength modifier the variables under study. After statistical evaluation of experimental design sampling time proved to be the most significant variable, and a more detailed kinetic study has been carried out. The 85 μm polyacrylate fibre was shown to be the most efficient one. Optimum conditions as well as quantitative values are shown and discussed. Toluene, dodecane, tetradecane, benzophenone, BHT and DiBP were found in the concentration range from 2 to 141 ng ml −1 .

The main objective of this paper is to study the co-pyrolysis of a Spanish low rank coal and a mineral waste oil (MWO) slurry. The goal is to process the coal, handling it as a slurry by using a waste as the fluid component of the slurry in a continuous-mode preparative scale pyrolysis unit. It has been shown that a MWO/coal slurry can be successfully processed in a pulsed feeding fluidized bed reactor. Liquid and gases fractions have been analysed for organic products and metals. High yields of valuable light olefins such as ethylene and propylene and light aromatics as benzene, toluene, xylene and naphthalene derivatives have been obtained. The results show that both quantity and quality of gases and liquids obtained are significantly improved in relation to those obtained from coal. Special attention has been paid to the fate of metals contained in the MWO/coal slurries and their distribution into the co-pyrolysis products. In particular, the distribution of six metals (Cd, Ni, Pb, Cu, Cr, V) has been studied. The data show that metals under study are totally or partially trapped in the char formed during co-pyrolysis. This way the contents of Pb, Cu, V and Ni in the pyrolysis products leaving the reactor is substantially lower than in the feeding what will facilitate the obtention of valuable products.

A new screening and semi-quantitative approach has been developed for direct analysis of polycyclic aromatic hydrocarbons (PAHs) and their nitro and oxo derivatives in environmental and biological matrices using atmospheric pressure solid analysis probe (ASAP) quadrupole-time of flight mass spectrometry (Q-TOF-MS). The instrumental parameters were optimized for the analysis of all these compounds, without previous sample treatment, in soil, motor oil, atmospheric particles (ashes) and biological samples such as urine and saliva of smokers and non-smokers. Ion source parameters in the MS were found to be the key parameters, with little variation within PAHs families. The optimized corona current was 4 µA, sample cone voltage 80 V for PAHs, nitro-PAHs and oxo-PAHs, while the desolvation temperatures varied from 300°C to 500°C. The analytical method performance was checked using a certified reference material. Two deuterated compounds were used as internal standards for semi-quantitative purposes together with the pure individual standard for each compound and the corresponding calibration plot. The compounds nitro PAH 9-nitroanthracene and oxo-PAH 1,4-naphthalenedione, were found in saliva and urine in a range below 1 µg/g while the range of PAHs in these samples was below 2 µg/g. Environmental samples provided higher concentration of all pollutants than urine and saliva.

The behaviour of several solid sorbents during the pyrolysis process of industrial waste oils in a bench-scale pyrolysis unit is studied. The concentrations of V, Ni, Pb, Cd, Cu and Cr in the waste oils and in the original sorbents as well as that obtained in the final valuable product liquid fraction are measured. Limestone, commercial active char, Samca char, activated Samca char and sepiolite were the solid sorbents used. 100% of the lead from the waste oils can be retained on limestone. The behaviour of both metals and sorbents and the influence of specific surface area as well as chemical nature of metals and sorbents are discussed. Final liquid fractions resulted in valuable industrial products.

The determination of polyaromatic hydrocarbons (PAHs) in industrial waste oils was studied. The optimized procedure consisted in using low pressure gel permeation chromatography to separate the fraction containing PAHs and PCBs from the matrix. Both groups of contaminants were further fractionated on a small column of 3% deactivated alumina, using hexane to elute the PCB fraction and then hexane–dichloromethane (95 + 5) to elute PAHs. The final analysis was carried out by HPLC on a 2(1-pyrenyl)ethyldimethylsilica column with hexane as mobile phase in the isocratic mode and with UV detection at three different wavelengths, to quantify 16 priority PAHs. Recoveries were between 89 and 99%. Four different industrial waste oil samples were analyzed and the results obtained are discussed.

Twenty-one individual chlorobiphenyls (CBs), including the most toxic non-ortho-CBs, were determined in 52 samples of sea mammals, harbour porpoise (Phoceana phoceana), dabs (Limanda limanda), seals (Phoca vitulina) and dolphins (Tursiops truncatus). The toxic non-ortho-CBs and mono-ortho-CBs were isolated from the di- and tri-ortho-CBs using a pyrenylsilica HPLC column prior to the final determination by GC with electron-capture detection. The distribution of the CBs in the different species were studied by principal component analysis. Separations of males and females, young and adult individuals and the different species of sea mammals were obtained based on the degree of accumulation of CBs.

Organochlorine compounds were measured in the air of two different sites. In the air of a Spanish National Park in the Pyrenees Mountains (Ordesa and Monteperdido) and in the surroundings of an industrial waste dump (Sabinanigo near to Huesca). The air sampling was carried out with a high volume air sampler, using polyurethane foam (PUF) and glass fiber filters (GFF) to collect both the gas phase and the particulate phase of these compounds. Recovery data of the analytical procedure as well as breakthrough values are shown. γ-HCH. a-HCH, a-endosulfan and hexachlorobenzene were found in all National Park samples in the range from 70 to 3076 pg/m3. The chlorobenzenes had the highest concentrations ([Sgrave]CB=1551–3512 ng/m3) in the dumping site. α-HCH and y-HCH were found in the range from 28 to 78 ng/m3.

This study aims to establish criteria under which to use industrial waste oils as alternative fuels for combustion under conditions of maximum environmental safety. Waste oils as well as the particulate matter emitted from their combustion were analysed and characterized. The size, morphology and composition of metals in the particulate matter contained in the oils as well as chlorine content were analysed by electron microscopy and X-ray microanalysis. Heavy metals were determined in the oil by ETAAS. All the oil samples characterized were burnt in an experimental combustor where the conditions of combustion were modified. The emitted particulate matter was chemically digested and Cr, V, Cd, Cu, Pb and Fe were determined in each final solution by ETAAS. The results obtained, the accumulation factors for metals and the relationship between combustion conditions and emission of particulate matter and metals, are discussed.

The absorption of some organochlorine and organophosphorus pesticides on low-density polyethylene (LDPE) films used as agricultural soil covers is studied. Four different types of LDPE films (black, normal, thermic, and extra low density) and a copolymer of ethylene and vinyl acetate (EVA) were selected to do the kinetic study. Temperature ranged from 24 to 50 °C, and contact time between plastic films and a standard solution of pesticides in aqueous phase varied between 3 and 20 days. As pesticides the following were studied: dicloran, malathion, procymidone, folpet, α- and β-endosulfan, chlorothalonil, chlorpyriphos, and methylchlorpyriphos. Kinetic equations of first order were obtained in all cases having kinetic constants from 6.5 × 10-4 to 1 × 10-4 days-1. Most of the pesticides studied were completely absorbed on the plastic films after 15 days of contact time. No degradation of pesticides was observed once they were absorbed on the plastic. Both the absorption process and the capacity of absorpti...

Four clean-up procedures for the determination of 15 organochlorine pesticides in animal diet are studied. These methods imply the use of solid adsorbents such as Silica-gel, Florisil, the use of a combined bed of Silica-gel and Florisil, as well as, HPLC — size exclusion chromatography. The recovery of each compound is considered as acceptable when the value is higher than 80%. The behaviour of each produre with the animal diet sample is studied. A certified reference material of animal diet is used to validate the proposed procedure.

Packaged food can contain non-intentionally added substances (NIAS) as a result of reaction and degradation processes or the presence of impurities in the raw materials used for the packaging production. This manuscript reviews the evidence of NIAS and their possible origin. One of the most challenging and difficult tasks when a sample of packaging materials arrives at the laboratory is knowing the procedure to apply for identifying the unknown compounds. This work proposes an analytical procedure for sample treatment, applicable to polymers as well as to migration samples, and for NIAS identification. The identification protocol comprises the determination of both volatile and non-volatile compounds. A review is presented of the most novel analytical techniques used for identification purposes, particularly high resolution mass spectrometry (HRMS).

Application of wood plastic composites (WPCs) obtained from recycled materials initially intended for landfill is usually limited by their composition, mainly focused on release of volatile organic compounds (VOCs) which could affect quality or human safety. The study of the VOCs released by a material is a requirement for new composite materials. Characterization and quantification of VOCs of several WPC produced with low density polyethylene (LDPE) and polyethylene/ethylene vinyl acetate (PE/EVA) films and sawdust were carried out, in each stage of production, by solid phase microextraction in headspace mode (HS-SPME) and gas chromatography–mass spectrometry (GC–MS). An odor profile was also obtained by HS-SPME and GC–MS coupled with olfactometry analysis. More than 140 compounds were observed in the raw materials and WPC samples. Some quantified compounds were considered WPC markers such as furfural, 2-methoxyphenol, N-methylphthalimide and 2,4-di-tert-butylphenol. Hexanoic acid, acetic acid, 2-methoxyphenol, acetylfuran, diacetyl, and aldehydes were the most important odorants. None of the VOCs were found to affect human safety for use of the WPC.

The analysis of sterols in biological fluids allows the clinical study of cholesterol related diseases. This research is focused on reducing the sample processing time of the determination of free and bonded sterols in human serum. Ten sterols were studied: cholesterol precursors (desmosterol, lanosterol, and cholestanol); phytosterols (stigmasterol, campesterol, sitosterol, and sitostanol) and oxysterols (7-α-hydroxy-4-cholesten-3-one, 24-hydroxycholesterol, and 27-hydroxycholesterol). Ultrasound assistance was used to diminish the reaction time during the alkaline hydrolysis for determining total sterols. Different retention mechanisms of solid-phase extraction were compared, two reversed-phase sorbents DSC-18 and polymeric Oasis-HLB and a novel zirconia-coated silica phase. DSC-18 and zirconia-coated silica were the most suitable sorbents to analyze these metabolites. The resulting extracts were analyzed by liquid chromatography coupled to mass spectrometry. The analytical parameters were determined and better values were observed with DSC-18 cartridges for most sterols. LOQ were in the low ng/mL level. Recoveries were in the range 85-99%. Average intermediate precision was 15%. Accuracy for both cartridges was more than 92%. Zirconia-coated silica showed better performance for the oxysterols, with recoveries around 90%. The procedure allows the determination of free and bonded sterol precursors, phytosterols, and oxysterols in human serum.

Acrylic adhesives are used to manufacture multilayer laminates that are used in food packaging to form the geometric shape of the package as well as to stick labels on the packages. Once applied on the packaging adhesives can supply potential migrants that could endanger the packaged food. Adhesives are complex matrices where intentionally and non intentionally added substances are present, but the identification of the migrants is required by law. In this study atmospheric pressure gas chromatography coupled to a quadrupole hyphenated to a time of flight mass spectrometer (APGC–MS/Q-TOF) has been explored for identification of unknowns coming from three different acrylic adhesives. The results are compared to those obtained by conventional GC–MS-Q (quadrupole). Sixteen compounds were identified by GC–MS/Q and five of them were confirmed by APGC–MS/Q-TOF as their molecular ions were found. Moreover, additional three new compounds were identified and their structure was elucidated working with the spectra obtained by APGC–MS/Q-TOF. This finding was very relevant as these compounds were biocides suspected to be allergenic and cytotoxic in humans. Migration studies were carried out using Tenax as solid food simulant and the results showed that the three acrylic adhesives tested in this work were safe for being used in food packaging materials since the migration of compounds previously identified was below the limit established in the current legislation.

Sample treatment is perhaps the most critical step in analysis and thus the most demanding area of analytical procedures. Solid samples almost always require extraction steps and it is in this area that novel and advanced techniques have been developed. This chapter contains a short description and literature review of the most novel sample treatment techniques for this task, including supercritical fluid extraction, pressurized liquid extraction, microwave-assisted extraction, ultrasound-assisted extraction, hyphenation, and miniaturization of techniques. In each case, the basic concepts on which the techniques are based, their advantages and drawbacks, and some applications are described. The relevant information on the analytes, techniques, and experimental procedures are included in two tables, to help the reader to select the most appropriate technique and make decisions about them. The data are based on more than 400 scientific references dealing with the subject. This is not an exhaustive list of techniques, matrices, and applications, but much useful information is provided. Common problems related to the matrix composition, hyphenated techniques for sample preparation, and versatility of the devices are discussed to give some ideas about new approaches. References are limited to 50, but the content corresponds to a much wider overview.

The efficiency of photo-oxidation, chemical oxidation by sodium hypochlorite, and ozonization for the industrial-scale removal of volatile organic compounds (VOCs) and odors from gaseous emissions was studied by applying these treatments (in an experimental system) to substances passing through an emission stack of a factory producing maize derivatives. Absorption and ozonization were the most efficient treatment, removing 75% and 98% of VOCs, respectively, while photo-oxidation only removed about 59%. The emitted chemical compounds and odors were identified and quantified by gas chromatography-mass spectrometry (in full-scan mode). In addition to presenting the results, their implications for selecting optimal processes for treating volatile emissions are discussed.

Lichens of the species Parmelia sulcata were collected from sites on both sides of the Somport tunnel (which links France and Spain) and atmospheric particles were collected by air samplers installed within and on either side of the tunnel. Polycyclic aromatic hydrocarbons (PAHs) in the lichen and particle samples were then extracted, identified, quantified, and compared to evaluate the potential utility of lichens as pollution biomonitors in remote areas. The origin of the PAHs was also assessed using the Phe/Ant, Flu/Pyr, Ant/Ant+Phe, Flu/Flu+Pyr, and BaA/BaA+Chr concentration ratios. The total concentration of 16 priority PAHs ranged from 6.79 to 23.3 microg/g in particles outside the tunnel, from 18.3 to 265.2 microg/g in particles inside the tunnel, and from 0.91 to 1.92 microg/g in the lichen samples. The PAH ratios found in the lichens and particulate matter indicate that they were of pyrogenic origin and that road traffic was a major contributor. Results from the lichen samples suggest that they may be excellent biomonitors of pollution in remote areas.

The determination of several compounds present in a commercial polycarbonate container intended to be used in microwave ovens which could be considered as potential migrants has been carried out by reversed-phase high-performance liquid chromatography (HPLC) with both ultraviolet (UV) and fluorescence detectors. Total dissolution with dichloromethane and polymer reprecipitation with methanol have been used to evaluate 100% potential migration as the worst case. The extract consisted of a complex mixture containing monomers, oligomers, UV stabilizers, antioxidants, degradation products, and other additives. Phenol, Bisphenol A, 2,4-di-tert-butylphenol, Cyasorb UV5411, bis(2-ethylhexylphthalate), Irganox 1076, and Irgafos 168 were identified by both retention times and fluorescence-to-UV ratios. Additional confirmation was achieved by HPLC with diode array detection and gas chromatography-mass spectrometry. Recovery percentages were in the range of 73.8-94.4%, the lowest one being for the antioxidant Irgafos 168 due to its transformation into the phosphate form and 2,4-di-tert-butylphenol. The concentrations of the studied analytes present in the polycarbonate container ranged between 0.9 and 240 microg.g(-)(1). The total dissolution conditions that may affect the final concentration of analytes, mainly Bisphenol A, are discussed.

The determination of Pb, V, Cr, Ni, Cd, Cu and Fe in particles of different size obtained from the combustion of waste oils has been carried out. The study consists of the separation of several fractions according to the size of particles, the wet digestion and the individual analysis by graphite furnace atomic absorption spectrometry of the mentioned metals. Taking into account the volatilization temperature of different compounds containing the metals and their distribution on the size fractions, the mineral speciation of metals is proposed.

A fast and sensitive high performance liquid chromatography with atmospheric pressure chemical ionization tandem mass spectrometry (HPLC-APCI-MS/MS) method to identify and quantify oxysterols, phytosterols and non-cholesterol sterols at the pico-molar concentration level in human serum in only one run was developed in this study. This method allows the simultaneous separation and quantitation of individual phytosterols, cholesterol precursors and oxidized derivatives of cholesterol without a derivatization step in a single run, thus providing a more confident quantitation of sterols in serum. After saponification, solid-phase extraction (SPE) used as a clean-up step and HPLC separation, detection by MS was developed using APCI and multiple ion monitoring modes. This method employs reversed-phase C18 SPE cartridges and serum calibrators, as well as isotopically labelled cholesterol as an internal standard added before sample processing. The time consumed for a single sample is reduced from the 4 hours of conventional sterol analysis to 1 hour including the chromatographic run time. The method has been evaluated by analyzing a certified cholesterol sample as well as by comparison to other two methods used as reference, based on GC and enzymatic reaction, respectively. Serum from 14 individuals was successfully analyzed. Detection limits for oxysterols, phytosterols and non-cholesterol sterols, all determined in a single run in small serum volumes, were between 0.47 and 1.69 pM. Intra-day precision was

Six different species of lichens (Parmelia sulcata Tayl., Evernia prunastri (L.) Ach., Ramalina farinacea, Pseudevernia furfuracea (L.) Zopf., Usnea sp. and Lobaria pulmonaria (Schreb.) Hoffm.) were collected in two mountain valleys in Central Pyrenees: the Aspe and Aragon valleys. Two multivariate techniques have been applied with different purposes, ANOVA and Discriminant Analysis (DA), to evaluate the data. The PAHs spatial distribution was studied in the three more abundant and widespread species in the area: P. sulcata, E. prunastri (L.) Ach. and R. farinacea in terms of total PAHs, PAHs related to the combustion processes and toxicity. Different behaviour of each lichen species to trap PAHs was found, being P. sulcata the best one to monitor the most persistent PAHs of pyrogenic origin and E. prunastri the most appropriate to provide information about pyrogenic and petrogenic PAHs. Traffic was the most relevant influence in PAHs bioaccumulation in lichen species.

Different clean‐up procedures for PCB analysis are compared. Sulphuric acid‐silica gel column was the most effective clean‐up procedure to determine PCBs in mineral waste oils.

In the present paper, the results obtained in the pyrolysis of four industrial waste oils (automotive, hydraulic, machine and cutting oil) are shown. The pyrolysis has been carried out at atmospheric pressure and 600°C. The continuous injection of the samples was into the bottom part of the reactor using a pump. Liquid and gases fractions have been analysed, organic products by gas chromatography and metals concentration by Graphite Furnace Atomic Absorption Spectrometry (GFAAS). The gases obtained are mainly formed by methane and light olefins, C 2 – C 4 , and the liquids contain an aromatic fraction of high industrial value. The behaviour of metals was also very different from one oil to another. Lead was the most affected metal in all of them, with a decrease ratio (concentration before and after the pyrolysis) from 165 for machine oil to 32 for the hydraulic oil. Pb, Cr, Cu, Ni, Pb and V were identified and quantified in each fraction. The results show that the automotive and machine waste oils are the better ones concerning the liquid yields. However, the hydraulic and cutting oils show a high conversion to gas products. The relationship between the type of waste oil and the products obtained is discussed.