0000000000003308
AUTHOR
Agustín Pastor
Burned bones forensic investigations employing near infrared spectroscopy
The use of near infrared (NIR) spectroscopy was evaluated, by using chemometric tools, for the study of the environmental impact on burned bones. Spectra of internal and external parts of burned bones, together with sediment samples, were treated by Principal Component Analysis and cluster classification as exploratory techniques to select burned bone samples, less affected by environmental processes, to properly carry out forensic studies. Partial Least Square Discriminant Analysis was used to build a model to classify bone samples based on their burning conditions, providing an efficient and accurate method to discern calcined and carbonized bone. Additionally, Partial Least Square regres…
Biomonitoring of non-persistent pesticides in urine from lactating mothers: Exposure and risk assessment
Abstract The aim of the present study was to assess the exposure to pesticides in urine from Spanish lactating mothers (n = 116). Six nonspecific (dialkyl phosphates) and 20 specific metabolites of organophosphate pesticides (OPs), herbicides and pyrethroids were analyzed. The most frequently detected biomarkers were diethyl phosphate, p-nitrophenol, 3,5,6-trichloro-2-pyridinol and 3-phenoxybenzoic acid, whose geometric means were 1.9 ng·mL−1, 0.8 ng·mL−1, 1.5 ng·mL−1 and 1.4 ng·mL−1, respectively. Herbicide metabolites were the least frequently detected biomarkers with detection frequencies between 0% (2,4,5-Trichlorophenoxyacetic acid) and 22% (2,4-Dichlorophenoxyacetic acid). Multiple re…
Determination of mercury by cold‐vapour technique in several tissues of treated American red crayfish (Procambarus clarkii)
Abstract Adult intermolt specimens of American red crayfish (Procambarus clarkii) collected from Lake Albufera (Valencia, Spain), were exposed to mercury during 96 h. The Hg‐concentrations used were 50, 100, and 250 μg Hg/1 as Cl2Hg. The content of mercury in muscle, midgut gland, antennal glands and gills was investigated. Determinations of mercury were made by cold‐vapour technique and AAS. The mercury levels in all examinated tissues increased significantly (ANOVA test, p < 0.01) with increasing Hg‐concentration in the water.
Target analysis and retrospective screening of veterinary drugs, ergot alkaloids, plant toxins and other undesirable substances in feed using liquid chromatography-high resolution mass spectrometry.
A comprehensive strategy combining a quantitative method for 77 banned veterinary drugs, mycotoxins, ergot alkaloids and plant toxins, and a post-target screening for 425 substances including pesticides and environmental contaminants in feed were developed using a QuEChERS-based extraction and an ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS). The quantitative method was validated after previous statistical optimisation of the main parameters governing ionisation, and presented recoveries ranging, in general, from 80 to 120%, with a precision in terms of Relative Standard Deviation (RSD) lower than 20%. The full-scan accurate mass data…
Electrothermal Atomic Absorption Spectrometric Diagnosis of Familial Hypercholesterolemia
We have developed a new nonradioactive assay to identify human low-density lipoprotein receptor defects. It is based on the incubation of cultured cells with colloidal gold-LDL conjugates and quantitation of the gold associated with the cells by electrothermal atomic absorption spectrometry. After an oxidative treatment with nitric and hydrochloric acids, the biological matrix interferes neither with the gold recovery nor with the gold measurements, which are linear, at least from 0.15 to 3 ng of gold. When cells expressing a functional LDL receptor are incubated with increasing amounts of colloidal-gold LDL conjugates, the obtained saturation curve parallels that described when [125I]LDL i…
Hard cap espresso extraction-stir bar preconcentration of polychlorinated biphenyls in soil and sediments.
Abstract A Nespresso © hard cap espresso machine has been employed for the quantitative extraction of polychlorinated biphenyls (PCBs) from sediments and soils. Sample extraction was performed from five grams of sample in less than 40 s, with 200 mL ethanol 40% (v/v) in water and PCBs were concentrated using stir bar sorptive extraction (SBSE) and determined by thermal desorption-gas chromatography-tandem mass spectrometry (TD-GC-MS-MS). Eleven PCB congeners (28, 52, 77, 80, 81, 101, 118, 138, 153,169, and 180) were determined in soils and sediments with limits of quantification in the 0.03–0.08 ng g −1 range. Extraction efficiency was established by the analysis of soil samples spiked with…
Room temperature acid sonication ICP-MS multielemental analysis of milk
Abstract Room temperature acid sonication of milk samples is proposed as a fast alternative methodology for the determination of the total content of 45 elements (Li, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Y, Mo, Ag, Cd, In, Sn, U, Sb, Te, Cs, Ba, Hg, Pb, Bi, Th, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, Hf and Ta) in milk by inductively coupled plasma mass spectrometry (ICP-MS). The aforementioned procedure involves a 10 min sample pre-treatment. Measurements were made in quantitative and semiquantitative (Totalquant ® ) modes of analysis using Rh as internal standard and Be, Ge, Tb and Re for internal calibration of the equipment in the semiquantitative mode. The…
Determination of indoor air quality of a phytosanitary plant.
A new methodology has been developed to determine volatile organic compounds (VOCs) and pesticides in ambient air using membrane based devices as passive samplers. Pesticides were determined by gas chromatography with mass spectrometry detection (GC-MS) after their microwave-assisted extraction (MAE) from the passive sampler and the required clean-up. On the other hand, VOCs were also caught with the same samplers and directly determined by head space (HS) coupled to GC-MS. The use of samplers filled with florisil and activated carbon allows us to catch with a simple device both, VOCs and pesticides, with a high vapor pressure. Results obtained in the deployment of samplers in different sit…
Chemical Element Levels as a Methodological Tool in Forensic Science
The aim of the present study was to define a methodological strategy for understanding how post- mortem degradation in bones caused by the environment affects different skeletal parts and for selecting better preserved bone samples, employing rare earth elements (REEs) analysis and multivariate statistics. To test our methodological proposal the samples selected belong to adult and young individuals and were obtained from the Late Roman Necropolis of c/Virgen de la Misericordia located in Valencia city centre (Comunidad Valenciana, Spain). Therefore, a method for the determination of major elements, trace elements and REEs in bone remains has been developed employing Inductively-Coupled Pla…
Biomonitoring of polycyclic aromatic hydrocarbons in the urine of lactating mothers: Urinary levels, association with lifestyle factors, and risk assessment
Abstract Polycyclic aromatic hydrocarbons (PAHs) are pollutants produced during incomplete combustion of organic matter and several industrial processes. Humans can be exposed to PAHs through ingestion of food, inhalation of tobacco smoke or polluted air, and dermal contact, causing immunologic, developmental, and reproductive problems. In the present research, eleven metabolites of PAHs were analyzed in the urine of 110 lactating women living in Spain (2015). PAH metabolites were extracted from the urine samples by liquid-liquid extraction and their determination was performed by liquid chromatography coupled to tandem mass spectrometry. In addition, information on lifestyle and dietary ha…
On-line speciation of mercury in fish by cold vapour atomic fluorescence through ultrasound-assisted extraction
A fully mechanized procedure has been developed for the speciation of mercury in fish samples by using cold vapour atomic fluorescence spectrometry (CV-AFS). Sample slurries in an acid mixture in the presence of a surfactant and with traces of K2Cr2O7, were injected into a flow system, sonicated and merged with 1 ml of an oxidant mixture of KBr/KBrO3 heated at 50 °C in a water bath and total Hg determined by CV-AFS. Sonicated sample slurries were also measured, in the absence of KBr/KBrO3, in order to obtain a second series of data which could be employed to establish the concentrations of free Hg(II). Different compositions of the acidic extractant solutions were evaluated by mixing HCl, H…
Indirect chronology method employing rare earth elements to identify Sagunto Castle mortar construction periods
A novel indirect chronology method has been developed to identify Sagunto Castle construction periods. The method is based on the use of inductively coupled plasma mass spectrometry (ICP-MS) to determine rare earth elements (REE) and other trace elements in mortars. Additionally, a no destructive geochemical analysis based on X-ray fluorescence (XRF) was employed for major elements determination. Collected chemical data were processed through Principal Component Analysis (PCA) to highlight any differences among the mortars belonging to different buildings and construction periods. The results show that PCA analysis permits to discriminate construction periods according to mortar sample REE …
Determination of 40 currently used pesticides in airborne particulate matter (PM 10) by microwave-assisted extraction and gas chromatography coupled to triple quadrupole mass spectrometry
A confirmatory and sensitive procedure has been developed for the determination of 40 currently used pesticides (Cups) in airborne particulate matter (PM 10) at trace level. The proposed method includes extraction of PM 10-bound pesticides by microwave-assisted extraction (MAE) followed by a gel permeation chromatography (GPC) clean-up and determination by GC-MS/MS. The injection mode and the main parameters in MS/MS were optimized. The matrix effect was also evaluated. Recoveries ranged from 70 to 120% except for pyrimethanil and pirimicarb. The limit of quantification (LOQ) ranged from 1.32 to 39.47 pg m(-3), when air volumes of 760 m(3) were collected. The method was applied to 38 sample…
Determination of lead in treated crayfish Procambarus clarkii: accumulation in different tissues.
The continual loading of trace metals into our environment represents a water pollution problem due to their toxic effects on aquatic biota. In addition, metal ions can be incorporated into food chains and concentrated by aquatic organisms to a level that affects their physiological state. There are several investigations on the toxic effects and bioaccumulation of lead in fishes, molluscs, and crustaceans. Lake Albufera (Valencia, Spain) and the surrounding rice-field waters are subjected to large loads of sewage and toxic industrial residues (including heavy metals) from many urban wastewaters in the area. In 1978, the American red crayfish Procambarus clarkii (Girard) appeared in Lake Al…
Determination of As, Sb, Se, Te and Bi in milk by slurry sampling hydride generation atomic fluorescence spectrometry
A simple and fast analytical procedure has been developed for the determination of As, Sb, Se, Te and Bi in milk samples by hydride generation atomic fluorescence spectrometry (HG-AFS). Samples were treated with aqua regia for 10min in an ultrasound water bath and pre-reduced with KBr for total Se and Te determination or with KI and ascorbic acid for total As and Sb, the determination of Bi being possible in all with or without pre-reduction. Slurries of samples, in the presence of antifoam A, were treated with NaBH(4) in HCl medium to obtain the corresponding hydrides, and AFS measurements were processed in front of external calibrations prepared and measured in the same way as samples. Re…
Determination of organic and inorganic anions in insect haemolymph and midgut contents by ion chromatography
A simple and rapid ion-exchange chromatographic method with conductimetric detection for the determination of carboxylic acids (succinic, malic and citric) and inorganic anions (chloride, phosphate and sulphate) in haemolymph and midgut content of Lepidoptera larvae is provided. The mobile phase is 0.975 mM phthalic acid at pH 4.1. The procedure of sample extractions was simple. Comparison of the results with whose reported in the bibliography showed that the values were similar. The ion-exchange chromatographic–conductimetric detection method permits the analysis of various organic and inorganic anions in small biological samples.
Dynamic reaction cell inductively couple plasma-mass spectrometry optimization for seawater analysis
Abstract A direct method for dynamic reaction cell inductively coupled plasma- mass spectrometry (DRC-ICP-MS) trace mineral elements determination in seawater was optimized by Experimental Statistical Design. Five instrumental parameters, such as radiofrequency, sample, nebulizer and reaction gas flows, rejection parameter q and axial field voltage were studied. A Plackett-Burman design was used for screening the most important parameters and the most significant ones were optimized with a Central composite design. Fifteen elements and different isotopes for some of these were considered through the study. The optimization was achieved by using three different reaction gases (NH3, CH4 and O…
Regional provenance of dolerite prehistoric objects through mineral analysis
Abstract A methodology based on the mineral analysis determination has been developed to identify the origin of dolerite stone outcrops collected to fabricate lithic objects during the Prehistoric period. The method is based on the use of inductively coupled plasma mass spectrometry (ICP-MS) to analyse rare earth elements (REE) and trace elements. Additionally a no destructive geochemical analysis based on X-ray fluorescence (XRF) was employed for major elements analysis. The aforementioned methodologies were applied to samples from different archaeological fields or natural outcrops located in the Mediterranean area of Spain, between Valencia and Alicante. Principal component analysis (PCA…
Determination of 3-MCPD by GC-MS/MS with PTV-LV injector used for a survey of Spanish foodstuffs
3-Monochloropropane-1,2-diol (3-MCPD) is the most common chemical contaminant of the group of chloropropanols. It can occur in foods and food ingredients at low levels as a result of processing, migration from packaging materials during storage and domestic cooking. A sensitive method for determination of 3-MCPD in foodstuffs using programmable temperature vaporization (PTV) with large-volume injection (LVI) gas chromatography (GC) with tandem mass spectrometry detection (MS/MS) has been developed and optimized. The optimization of the injection and detection parameters was carried out using statistical experimental design. A Plackett-Burman design was used to estimate the influence of reso…
Biomonitoring of bisphenols A, F, S in human milk and probabilistic risk assessment for breastfed infants
The present study addresses the presence of bisphenols A (BPA) and its analogs bisphenol F (BPF) and S (BPS) in milk of 120 mothers living in Valencia (Spain) and participating in the BETTERMILK project (year 2015). We also studied the factors that could influence the BPA levels and estimated the exposure and the risk for breast fed infants. The frequency of detection of total (conjugated + unconjugated) and unconjugated-BPA were 83% and 77%. with a geometric mean of 0.29 ng/mL and 0.15 ng/mL, respectively. The frequency of detection was much lower for total-BPF (22%) and total-BPS (1.1%). The place of residence of the mother and the use of personal care products showed significant associat…
Risk assessment of exposure to phthalates in breastfeeding women using human biomonitoring
In this study, we assessed the presence of 14 phthalate metabolites in the urine of 104 lactating mothers from Valencia (Spain) who took part in the human biomonitoring project BETTERMILK. Nine of the metabolites studied showed detection frequencies >80%, whereas the rest of the metabolites presented low detection frequencies (<5%). The concentrations ranged from <LoQ to 1291 ng/mL with monoethyl phthalate showing the highest concentration, with a geometric mean of 34.90 ng/mL. In general, the phthalate metabolite levels quantified in the present study were lower than the urinary levels found in previous studies that involved lactating mothers. The consumption of packaged juices and the fre…
Determination of Third-Generation Synthetic Cannabinoids in Oral Fluids.
Abstract A procedure has been developed for the determination of third-generation synthetic cannabinoids in oral fluid samples by using a semi-automated microextraction by packed sorbent (MEPS) procedure and gas chromatography–mass spectrometry (GC–MS) determination. Five synthetic cannabinoids were employed as model compounds 5F-ADB, MMB-CHMICA, THJ-2201, CUMYL-4CN-BINACA and MDMB-CHMCZCA. The most adequate operative conditions for MEPS were evaluated giving quantitative recoveries, from 89 to 124%, in synthetic and field saliva samples spiked with 125 and 250 μg/L of the studied cannabinoids, with the exception of MDMB-CHMCZCA in field saliva samples that provided slightly lower recoverie…
Variación química intrasquelética relacionada a la diagénesis en los restos óseos de c/En Gil (Valencia)
El objetivo de esto estudio ha sido definir una estrategia para una correcta selección de muestras de huesos inhumados (femures y costillas) menos afectados por los procesos diagéneticos, determinado los contenidos de elementos mayoritarios, trazas y REEs. Intentando en este modo de reconstruir el proceso de transición de los elementos desde el hueso al depósito tafonómico y viceversa. Una atenta selección de las muestras es determinante para que los análisis químicos puedan contribuir correctamente a una reconstrucción de la alimentación, las dinámicas de desplazamiento y las enfermedades de las poblaciones antiguas. Las muestras analizadas pertenecen a individuos hallados en las necr…
Non-destructive analytical methods to study the conservation state of Apadana Hall of Persepolis.
Atmospheric and biological agents are the main enemies of the building material conservation. In this work an innovative methodological approach, based on Near Infrared Spectroscopy (NIR) and X-Ray Fluorescence Spectroscopy (XRF), has been employed to evaluate the conservation state of Persepolis limestone samples collected both, under a protective shelter and outside the shelter, at Apadana Audience Hall area in Persepolis. The use of NIR spectra permitted to discriminate, by using Principal Component Analysis (PCA), the differences between samples collected inside and outside the protective shelter and we have been able to identify a major degradation state of the out shelter stone sample…
Optimization of large-volume injection for the determination of polychlorinated biphenyls in children's fast-food menus by low-resolution mass spectrometry.
International audience; This study includes the determination of five indicator polychlorinated biphenyls (PCBs) (52, 101, 153, 138, and 180), six non-ortho PCBs (35, 80, 81, 77, 126, and 169), and two mono-ortho PCBs (28 and 118) in fast food for children. A freeze-dried sample of 10 g is extracted by using pressurized n-hexane in two 5 min cycles at 120 degrees C and 100 mbar. Fatty extracts were cleaned up by means of acetonitrile/n-hexane partitioning and gel-permeation chromatography. The fractionation of non-ortho, mono-ortho, and indicator PCBs was made on graphitized carbon solid-phase extraction cartridges by using n-hexane, n-hexane/toluene (99:1, v/v), and toluene as elution solv…
Determination of volatile organic compounds in contaminated air using semipermeable membrane devices
Abstract Semipermeable membrane devices (SPMDs) were evaluated as passive samplers for the determination of 26 volatile organic compounds (VOCs) in contaminated air of occupational environments. A direct methodology based on the use of head-space-gas chromatography–mass spectrometry (HS-GC–MS) was developed for VOCs determinations in SPMDs, without any sample pre-treatment and avoiding the use of solvents. A desorption temperature of 150 °C for 10 min was sufficient for a sensitive VOCs determination providing limits of detection in the range of 15 ng SPMD−1 for 21 of 26 studied compounds. Linear and equilibrium uptake models were established for each VOC from compound isotherms. Highly vol…
Niveles de plomo en los individuos de la necrópolis tardorromana de la c/ Virgen de la Misericordia (Valencia)
El objetivo general de este estudio ha sido determinar los contenidos de plomo (Pb) en restos de huesos y suelos de la necrópolis de la c/ Virgen de la Misericordia (Valencia) para reconstruir el proceso de transición del elemento (desde el sedimento hacia los huesos y viceversa) debido a la acción de los procesos diagenéticos.
Determination of acrylamide in foods by pressurized fluid extraction and liquid chromatography-tandem mass spectrometry used for a survey of Spanish cereal-based foods.
An automated and rapid method for the determination of acrylamide in different food products is presented. The method involves pressurized fluid extraction (PFE) of foods with acetonitrile and precipitation with Carrez reagents. The final extract is analysed by liquid chromatography coupled to electrospray ionization tandem mass spectrometry (ESI-MS-MS). The main parameters affecting the performance of ESI-MS-MS and PFE were optimized using a design of experiments approach. The limit of quantification of the method was 5 microg kg(-1), and recoveries from incurred samples ranged between 93 and 101%. The accuracy was evaluated using the reference test materials FAPAS T3002, T3005 and T3011. …
Biomonitoring of parabens in human milk and estimated daily intake for breastfed infants
In this study, we assessed the presence of four parabens in human milk of 120 mothers from Valencia (Spain) which took part in a human biomonitoring project (BETTERMILK). The detection frequency ranges of parabens were 41-60% and 61-89% for unconjugated- and total (unconjugated + conjugated)-parabens, respectively. The concentrations ranged from <LoQ to 31 ng/mL and from <LoQ to 49 ng/mL for unconjugated- and total-parabens, respectively. The frequency of use of some cosmetic products and human milk protein levels were the main predictors of parabens in milk. The study evidences the presence of both conjugated and unconjugated paraben forms in human milk. The newborns estimated daily intake…
Development of a simple and low cost device for vapour phase Fourier Transform Infrared spectrometry determination of ethanol in mouthwashes
Abstract A new vapour phase manifold coupled with Fourier Transform Infrared (FTIR) spectroscopy was developed for ethanol determination in mouthwashes. Two microliters of samples were injected, without any previous pre-treatment into a reactor heated at 70 °C, and the vapour phase generated transported to the FTIR spectrometer using a carrier nitrogen flow of 6 ml min−1. FTIR spectra were continuously recorded, as a function of time, by accumulating two scans and employing 8 cm−1 nominal resolution. Analytical measurements for ethanol were made in the range from 1130 to 992 cm−1 with a baseline defined between 1158 and 957 cm−1. After ethanol measurement the carrier flow was increased to 3…
Assessment of air passive sampling uptakes for volatile organic compounds using VERAM devices
Abstract A calibration chamber has been designed and employed for the simple and easy determination of uptake sampling rate (RS) of volatile organic compounds (VOCs) from air using passive samplers. A flow of clean air was continuously spiked, at a constant VOC concentration, by the microinjection of a standard solution by means of a T-type tube. The developed system allowed the complete evaporation at room temperature of the standard solution in acetone and the air concentration of VOCs was easily controlled by the regulation of the clean air flow, the standard solution concentration and its flow. Active sampling was employed for monitoring the true concentration of the evaluated compounds…
Determination of arsenic and antimony in milk by hydride generation atomic fluorescence spectrometry
Abstract A highly sensitive procedure has been developed for total arsenic and antimony determination in milk samples by hydride generation atomic fluorescence spectrometry after microwave-assisted sample digestion. The discrete introduction of 2 ml of digested sample in the automated continuous flow hydride generation system allows us to reduce drastically the sample and HCl consume and to determine several elements from a same sample digestion. The method provides detection limits of 0.006 and 0.003 ng ml−1, a sensitivity of 2390 and 2840 fluorescence units per ng ml−1 for As and Sb respectively, and average relative standard deviation of 2.3% for As and 4.8% for Sb. The analysis of cow m…
Analysis of Sagunto Ibero-Roman votive bronze statuettes by portable X-ray fluorescence
Abstract The main objective of this work was the study of chemical composition of an important collection of Ibero-Roman votive bronze statuettes exposed in the Archaeological Museum of Sagunto (Spain). Precision and accuracy of the measurements were obtained developing a proper analytical method, also avoiding any possible damage to the studied objects using a portable energy dispersive X- ray fluorescence system. Principal Components Analysis (PCA) to discriminate between groups based on ratios Fe/Cu, Pb/Cu, Sn/Cu, Ag/Cu, Ni/Cu and Impurities/Cu were employed to observe differences between the used smelting, manufacturing processes and raw materials. The characterisation of bronze statuet…
Determination of bisphenol diglycidyl ether residues in canned foods by pressurized liquid extraction and liquid chromatography–tandem mass spectrometry
Abstract A new confirmatory method for simultaneous determination of bisphenol diglycidyl ether residues (BADGE, BADGE·H2O, BADGE·2H2O, BADGE·H2O·HCl, BADGE·HCl, BADGE·2HCl, BFDGE and BFDGE·2HCl) from canned food has been developed. The proposed method includes extraction by pressurized liquid extraction (PLE) followed by liquid–liquid partition and purification by solid phase extraction (SPE). Several solvent systems and different operating conditions (time, temperature) have been investigated for PLE optimization. A reversed-phase high-performance liquid chromatography (RP-HPLC) coupled to atmospheric pressure chemical ionisation tandem mass spectrometry (APCI-MS–MS) method was developed …
Determination of chromium in treated crayfish,Procambarus clarkii, by Electrothermal AAS: Study of chromium accumulation in different tissues
In the present study, the authors investigated the accumulation of chromium in muscle, hepatopancreas, antennal glands, and gills of Procambarus clarkii (Girard) from Lake Albufera following Cr(VI)-exposure. Determinations of chromium were made by using Electrothermal Atomic Absorption Spectroscopy and the standard additions method.
Low temperature headspace desorption of volatile organic compounds trapped in air sampling solid-supports
Environmental context. The monitoring of volatile organic compounds (VOCs) in air is of great importance for air quality on both local and global scales. The determination of VOCs can be carried out by gas chromatography–mass spectrometry (GC-MS) after active or passive sampling and (high temperature) thermal desorption. An attractive alternative would be to combine GC-MS with headspace (HS) systems as it allows simpler, faster, low temperature desorption. We present here the first report of HS-GC-MS for the determination of VOCs in air sampled using solid supports. Abstract. The use of a headspace (HS) for low temperature desorption of VOCs, previously sorbed from indoor air on solid supp…
Anthropogenic units fingerprinted by REE in archaeological stratigraphy: Mas d'Is (Spain) case
Abstract On occasions, archaeologists have to deal with serious difficulties to differentiate between processes that ultimately are responsible for the formation of stratigraphic units. Sometimes we face problems related with depositional units in multilayered deposits and other times, we ask for the character of some dark surface soils, very similar to natural paleosols and usually associated with archaeological findings. In both cases, the problems we must address concern the relative impact of human activities. The imbalance between anthropic and natural processes in the formation of archaeological deposits is crucial for a correct interpretation of the processes involved in the formatio…
Ultrastructural Alterations of Midgut Epithelium, but Not Greater Wing Fluctuating Asymmetry, in Paper Wasps (Polistes dominula) from Urban Environments
Polistes paper wasps can be used to monitor trace metal contaminants, but the effects of pollution on the health of these insects are still unknown. We evaluated, in a south-eastern area of Spain, whether workers of Polistes dominula collected at urban and rural sites differ in health of midgut tissue and in fluctuating asymmetry, an estimate of developmental noise. We found that wasps collected at the urban sites had abundant lead (Pb)-containing spherites, which were less visible in wasps from the rural sites. Evident ultrastructural alterations in the epithelium of the midgut of the wasps collected at the urban sites included broken and disorganized microvilli, a high amount and density …
Evaluation of working air quality by using semipermeable membrane devices
Abstract It has been evaluated the use of semipermeable membrane devices (SPMDs) as passive samplers of organophosphorus pesticides from air, in order to determine the contamination of working environments. Additionally, the use of SPMDs as portable samplers has been also considered. The analytical methodology for the determination of diazinon, chlorpyrifos-methyl, pirimiphos-methyl, chlorpyrifos and fenthion in SPMDs exposed to contaminated air was based on microwave-assisted extraction and gas chromatography with mass spectrometry determination. Limit of detection (LOD) values from 2 to 4 ng SPMD−1 and repeatability from 2 to 7% were obtained by using the aforementioned methodology. Theor…
Effect of cadmium pre-exposure in cadmium accumulation by brine shrimp Artemia: Involvement of low-molecular-weight cadmium-binding ligands
Abstract Cadmium is a ubiquitous non-essential element that possesses high toxicity and is easily accumulated from the environment by aquatic organisms. It is known that pre-exposure to cadmium increases the resistance of animals to a subsequent exposure. In this work, we report studies of the effect of pre-exposure to cadmium on the accumulation of this metal from seawater by brine shrimp Artemia, as well as the involvement of low-molecular-weight cadmium-binding ligands in this process. During the pre-exposure experiments, animals were kept in seawater containing 20 mg/litre Cd for 24 h and then transferred to clean seawater for 48 h. Afterwards, pre-exposed and control animals were expos…
Cadmium-binding proteins in midgut gland of freshwater crayfishProcambarus clarkii
Metallothioneins, metal binding proteins, were originally isolated and characterized by Margoshes and Vallee. These proteins have a high affinity for various heavy metals, particularly cadmium and mercury and have extensively been studied in mammals. Metal binding proteins have been observed in a variety of marine invertebrates; however, there is very little information available on metal binding proteins in freshwater invertebrates, and particularly in freshwater crustaceans. Cadmium is an ubiquitous non essential element which possesses high toxicity to aquatic organisms. Cadmium binding proteins observed in invertebrates have similar characteristics to mammalian metallothioneins. In 1978…
Using semi-permeable membrane devices as passive samplers
Abstract We discuss the present state of, and future developments in, using semi-permeable membrane devices (SPMDs) for environmental monitoring of organic pollutants. SPMDs allow the determination of time-weighted average concentrations of bioavailable pollutants in the sampled media, reducing significantly the costs of analysis compared with active samplers. We summarize developments in SPMDs, including simplified devices and devices modified by incorporating solvents other than triolein, and applications. We review contaminants (e.g., organotin compounds, polycyclic musk, triclosan, petroleum biomarkers, nitrated PAHs, polychlorinated naphthalenes and a wide range of pesticides sampled i…
Biomonitoring of heavy metal distribution in the Western Mediterranean area of Spain
Hydride generation atomic fluorescence spectrometric determination of ultratraces of selenium and tellurium in cow milk
Abstract A sensitive procedure has been developed for selenium and tellurium determination in milk by hydride generation atomic fluorescence spectrometry (HG-AFS) after microwave-assisted sample digestion. The method provides sensitivity values of 1591 and 997 fluorescence units ng−1 ml−1 with detection limits of 0.005 and 0.015 ng ml−1 for Se and Te, respectively. The application of the developed methodology to the analysis of cow milk samples of the Spanish market evidenced the presence of concentration ranges from 11.1 to 26.0 ng ml−1 for Se, and from 1.04 to 9.7 ng ml−1 for Te having found a good comparability with data obtained after dry-ashing of samples.
Combined target and post-run target strategy for a comprehensive analysis of pesticides in ambient air using liquid chromatography-Orbitrap high resolution mass spectrometry
Abstract A comprehensive strategy for the analysis of current airborne pesticides has been developed using liquid chromatography coupled to high resolution mass spectrometry. The methodology includes both quantitative target analysis and post-run target screening analysis. The quantitative method was validated after a previous statistical optimisation of the main factors governing the ion source ionization and a study of the single-stage Orbitrap fragmentation through the HCD cell. The quantitative method presented recoveries ranging from 73 to 116%, with precision (RSD) lower than 20%, for the 35 substances in the scope of the target method. The full-scan accurate mass data were acquired w…
Cadmium binding proteins induced in exposed freshwater crayfish Procambarus clarkii.
This work describes results on the characterization of cadmium binding proteins (Cd-BPs) obtained from cadmium exposed freshwater crayfish Procambarus clarkii. After acclimation to laboratory conditions, induction of Cd-BPs was achieved by water exposure at a concentration of 100 micrograms Cd/L during 2, 15, and 30 d. In accordance with the method followed by Engel and Brouwer, in each case two midgut glands were minced and homogenized in Tris-HC1 buffer with PMSF to prevent protease activity and DTT to maintain reducing conditions. The homogenate was centrifuged, heat treated, applied to a column of Sephadex G-75, and eluted with the same buffer (pH 8.6). Absorbances of the fractions coll…
Gamificación: El concurso como actividad grupal de enseñanza/aprendizaje
[EN] The present study consist of the use of game mechanics to promote the development of applications and activities to stimulate, in an attractive way but without sacrificing the rigor required, the teaching and learning in the subjects of Chemistry and Analytical Chemistry in Chemistry degree.
Quantification of cadmium-induced metallothionein in crustaceans by the silver-saturation method
Metallothionein (MT) has been proposed as a specific biochemical probe for metal exposure of aquatic organisms. It is recognized that its usefulness as a monitoring tool depends on the full understanding of its function and on the possibility of measuring its concentration in tissues. Therefore the study of MT in crustaceans is interesting from two different points of view: the need to understand mechanisms associated with the toxicology of metals, and the potential use of this protein for monitoring metal-contamined environments. Several methods have been developed for quantitative measurements of MT in biological samples. Immunochemical and electrochemical procedures are reliable techniqu…
Levels of heavy metals in some marine organisms from the western Mediterranean area (Spain)
Development of a pressurised liquid extraction and liquid chromatography with electrospray ionization-tandem mass spectrometry method for the determination of domoic acid in shellfish.
Amnesic shellfish poisoning (ASP) is a potentially lethal human toxic syndrome which is caused by domoic acid (DA) that originates in marine phytoplankton belonging to the Pseudonitzschia genus. A confirmatory and sensitive procedure has been developed and validated for the determination of DA in shellfish. The proposed method includes pressurised liquid extraction (PLE) with methanol/acetone (9:1), florisil ® cleanup purification inside the PLE extraction cell and detection by liquid chromatography (LC) coupled to electrospray ionization in positive mode tandem mass spectrometry (ESI-MS–MS). Comparison of ionization sources (ESI, atmospheric pressure ionization (APCI) atmospheric pressure …
Wide-range screening of banned veterinary drugs in urine by ultra high liquid chromatography coupled to high-resolution mass spectrometry
In this work, an ultra high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) methodology is proposed for the multi-class multi-residue screening of banned and unauthorized veterinary drugs in bovine urine, using an Orbitrap Exactive™ analyzer working at a resolving power of 50,000 FWHM in full scan, both in positive and negative mode. The method currently covers 87 analytes belonging to different families such as steroid hormones, β-agonists, resorcylic acid lactones (RAL), stilbens, tranquillizers, nitroimidazoles, corticosteroids, NSAIDs, amphenicoles, thyreostatics and other substances such as dapsone. A database including the elemental composition, the po…
Characterization and sources of Paleolithic–Mesolithic ochre from Coves de Santa Maira (Valencian Region, Spain)
Optimization of Resolving Power, Fragmentation, and Mass Calibration in an Orbitrap Spectrometer for Analysis of 24 Pesticide Metabolites in Urine
Mass spectrometer parameters such as Resolving Power, type of fragmentation, and mass calibration mode were optimized in the analysis of 24 pesticide metabolites in human urine using Ultra-High Pressure Liquid Chromatography coupled to Orbitrap High-Resolution Mass Spectrometer (UHPLC-HRMS). The best results were achieved with a Resolving Power of 25,000 FWHM and by applying Collision Induced Dissociation fragmentation mode (40 eV).
Chert Nucleus and Cortex Characterization for Archaeological Provenance Study Tested in the Prebaetic System Region (Valencian Community, Spain)
The characterization of chert artifacts and the identification of their raw material is a pivotal issue in archaeology for the comprehension of economic and territorial patterns related to prehisto...
Assessing air quality inside vehicles and at filling stations by monitoring benzene, toluene, ethylbenzene and xylenes with the use of semipermeable devices
BTEX (benzene, toluene, ethylbenzene, and xylenes) were used as target molecules to evaluate the quality of air inside motor vehicles and near filling stations, using semipermeable membrane devices (SPMDs) as low-cost passive sampling devices. A direct, fast, simple methodology based on the use of headspace-gas chromatography-mass spectrometry detection (HS-GC-MS) was developed for BTEX determinations, without any sample pre-treatment. SPMDs (25.4 cm2 surface, filled with 100 microL triolein) were employed as static samplers. After the selected deployment time, the SPMDs were heated inside a HS vial at 150 degrees C for 20 min and BTEX compounds were determined by GC-MS in selected ion moni…
Multi-residue analysis of 30 currently used pesticides in fine airborne particulate matter (PM 2.5) by microwave-assisted extraction and liquid chromatography–tandem mass spectrometry
A confirmatory and rapid procedure has been developed for the determination of 30 currently used pesticides (CUP) in fine airborne particulate matter (PM 2.5) at trace level. The proposed method includes extraction of PM 2.5-bound pesticides by microwave-assisted extraction (MAE) followed by a direct injection into LC-MS/MS. The main parameters affecting the MAE extraction (time, temperature and volume of solvent) were optimised using statistical design of experiments (DoE). The matrix effect was also evaluated. Recoveries ranged from 72 to 109% and the limit of quantification (LoQ) was 32.5 pg m(-3) for chlorpyrifos, 13.5 pg m(-3) for fenhexamid, imazalil and prochloraz, and 6.5 pg m(-3) f…
Biological mineral content in Iberian skeletal cremains for control of diagenetic factors employing multivariate statistics
Abstract The aim of this study was to define a strategy for a correct selection of bone samples by employing inductively coupled plasma optical emission spectroscopy (ICP-OES) for reconstructing the biological mineral content in bones through the determination of major elements, trace elements and Rare Earth Elements (REE, lanthanides) in skeletal cremains of ancient Iberians (III–II B.C), discovered in the Necropolis of Corral de Saus (Moixent, Valencia) between 1972 and 1979. The biological mineral content was determined taking into account diagenetic factors. A control method for a better reading of results was applied. To explore large geochemical datasets and to reduce the number of va…
Analysis of stratigraphical sequences at Cocina Cave (Spain) using rare earth elements geochemistry
This study investigates the stratigraphical sequence of Cocina Cave (Spain) employing and testing for the first time the capability of rare earth elements as markers of human activities in caves. Located in Dos Aguas (Valencian Community, Spain), Cocina Cave is characterized by the presence of several Holocene archaeological deposits from the final Mesolithic to the present day and is a pivotal site for understanding the socio‐ecological dynamics of the last hunter‐gatherer inhabitants of the Iberian Peninsula and the transition to pastoral and agricultural economies in the Western Mediterranean. However, the identification of strata from particular time‐periods in the cave is often difficu…
Air monitoring of selected volatile organic compounds in wineries using passive sampling and headspace-gas chromatography–mass spectrometry
Abstract Volatile compounds released during the production of wine at different steps of the winemaking process were evaluated using semipermeable membranes based passive samplers. Preliminary data on the differences between five wine varieties were provided together with the indoor quality of air to which winery workers are exposed during their professional activity. A simple, green and fast analytical methodology was employed for the direct analysis of deployed samplers by using head space (HS) gas chromatography–mass spectrometry (GC–MS) without any sample pre-treatment and avoiding the use of solvents. Terpenes as styrene, pinene, p-cymene and limonene were found at concentration levels…
Chemical and mineralogical analyses on stones from Sagunto Castle (Spain)
Abstract For the first time, an archaeometric study was carried out on the carbonate rock ashlars of the Sagunto Castle. The studied site is one of the most important and best preserved Spanish archaeological and architectural monuments, characterized by different construction phases from the Roman period to Modern Ages. Forty samples collected from thirteen different structures of Sagunto Castle and two quarries, located in the Sagunto's hill were used for comparative purposes. The samples were analyzed by X-ray diffraction, X-ray fluorescence and inductively coupled plasma mass spectrometry to determine their mineralogical and elemental composition. The obtained data show similar chemical…
Aroma compounds in wine as influenced by apiculate yeasts
Aroma compounds of wines resulting from fermentation of sterile grape musts from Monastrell variety inoculated with pure and mixed cultures of apiculate and Saccharomyces yeasts, were isolated and analyzed by gas chromatography with flame ionization and mass spectrometry. Samples fermented with mixed cultures produced a higher concentration of selected compounds and higher total amounts of alcohols and acids, in contrast with wines produced with pure cultures of Saccharomyces spp. Apiculate yeasts are important in the chemical composition and quality of wine.
An innovative multi-analytical approach based on spectroscopic and electrochemical techniques to study a complex Roman amphorae collection
Abstract An innovative multi-analytical approach for the classification of ancient pottery sherds was tested. Twenty Roman amphorae fragments belonging to different known typologies and twenty-seven unclassified ones from a complex Sagunto Archaeological Museum (Spain) collection were studied by multielement analysis (X-ray fluorescence spectroscopy and inductively coupled plasma mass spectrometry), Fourier-transform near infrared spectroscopy and voltammetry of immobilized microparticles employing a minimal amount of sample. Chemometric analysis based on principal component analysis allowed the identification of most of the unclassified samples, proving the importance and reliability of th…
New perspectives in the use of semipermeable membrane devices as passive samplers.
This review shows the state of the art, from 2000 to nowadays, of the use of semipermeable membrane devices (SPMDs) for monitoring persistent organic pollutants in both, air and aquatic environments. Since their first use in 1990, SPMDs have been employed for many environmental purposes, like air and water pollution monitoring. We have focussed the study in three subjects: (i) novel compounds accumulated by SPMDs, (ii) modifications of SPMDs to improve their specific uptake properties and (iii) alternatives in sample pre-treatment for the determination of pollutants accumulated in SPMDs.
GC–MS characterization of contemporary pesticides in PM10 of Valencia Region, Spain
Pesticides in the inhalable fraction of particulate matter (PM10) should be well tracked in order to contribute information to future exposure assessment in individuals of the general public. A total of 40 current-used pesticides and metabolites were searched for in ambient air samples collected from January through December 2010. The samples were taken from one remote, one urban and three rural sites in Valencia Region (Spain) and analyzed using liquid chromatography coupled to mass spectrometry in tandem (LC-MS/MS). In the PM10 fraction 17 pesticides and metabolites were detected overall, two of them currently banned (carbofuran and omethoate, although the latter is a metabolite of the pe…
Prediction of alkaline earth elements in bone remains by near infrared spectroscopy.
An innovative methodological approach has been developed for the prediction of the mineral element composition of bone remains. It is based on the use of Fourier Transform Near Infrared (FT-NIR) diffuse reflectance measurements. The method permits a fast, cheap and green analytical way, to understand post-mortem degradation of bones caused by the environment conditions on different skeletal parts and to select the best preserved bone samples. Samples, from the Late Roman Necropolis of Virgen de la Misericordia street and En Gil street located in Valencia (Spain), were employed to test the proposed approach being determined calcium, magnesium and strontium in bone remains and sediments. Coef…
Lanthanides Revealing Anthropogenic Impact within a Stratigraphic Sequence
Difficulties to differentiate between anthropogenic and natural processes in the formation of archaeological deposits are crucial for a correct interpretation not only of the actions involved in the development of archaeological sites, but also of their occupation-abandonment dynamics and the understanding of their spatial behaviors and relationship with the environment. We have carried out lanthanides (rare earth elements “REE”) analysis to distinguish anthropogenic from natural stratigraphic units in sediments using the advantage of the high sensibility, precision, and accuracy of ICP-MS measurements. In the Neolithic site of Mas d’Is (Alacant, Spain), we have applied REE analysis in a hu…
Poisoning histories in the Italian renaissance: The case of Pico Della Mirandola and Angelo Poliziano.
Giovanni Pico della Mirandola and Angelo Poliziano were two of the most important humanists of the Italian Renaissance. They died suddenly in 1494 and their deaths have been for centuries a subject of debate. The exhumation of their remains offered the opportunity to study the cause of their death through a multidisciplinary research project. Anthropological analyses, together with documentary evidences, radiocarbon dating and ancient DNA analysis supported the identification of the remains attributed to Pico. Macroscopic examination did not reveal paleopathological lesions or signs related to syphilis. Heavy metals analysis, carried out on bones and mummified tissues, showed that in Pico's…
Study of passive sampling of polycyclic aromatic hydrocarbons in gas phase using Amberlite XAD resins as filling materials of semipermeable membranes
Abstract In this work, a study was performed to evaluate the use of Amberlite XAD resins (XAD-2, XAD-4 and XAD-16), for the first time, as filling materials for low-density polyethylene membranes, which will be inserted as passive samplers for polycyclic aromatic hydrocarbons (PAHs) in gas phase. The use of samplers deployed for 48 h evidenced a relative capability to retain the compounds under study. A detailed study was performed to evaluate the recovery of analytes from the sampler through microwave-assisted extraction by using acetonitrile. A clean-up step using alumina-C18 cartridges was necessary before determination of the PAHs by high performance liquid chromatography with fluoresce…
HPLC determination of oxadiazon in commercial pesticide formulations
A simple, fast and precise high performance liquid chromatographic (HPLC) procedure has been developed for the determination of oxadiazon in emulsifiable concentrated pesticide formulations. 20 µL of diluted sample in acetonitrile were injected in a Kromasil C18 (250 ×am injetados em uma coluna Kromasil C18 4.6 mm, 5 µm) column, using acetonitrile:water (80:20) as mobile phase at 1 mL min-1 flow rate and oxadiazon determined by absorbance measurement at 292 nm. A theoretical limit of detection of 0.02 µg mL-1, a limit of quantification of 0.047 µg mL-1, corresponding to a 0.02 and 0.07% m/v in the original sample, and a relative standard deviation of 0.08% for three replicate analysis of sa…
The Use of Amberlite Adsorbents for Green Chromatography Determination of Volatile Organic Compounds in Air
Passive samplers have been widely used for volatile organic compounds determination. Following the green chemistry tendency of the direct determination of adsorbed compounds in membrane-based devices through using head space direct chromatography analysis, this work has evaluated the use of Amberlite XAD-2, XAD-4, and XAD-16 adsorbents as a filling material for passive samplers. Direct analysis of the membranes by HS-GC-MS involves a solvent-free method avoiding any sample treatment. For exposed membranes, recoveries ranged from 10% to 203%, depending on the compound and adsorbent used. The limit of the detection values ranged from 1 to 140 ng per sampler. Acceptable precision and sensitivi…
Multielemental determination of trace mineral elements in seawater by dynamic reaction cell inductively coupled plasma- mass spectrometry after Al(OH)3 coprecipitation
Abstract A simple method has been developed for the simultaneous determination of 12 trace mineral elements in seawater using, in some cases, several target isotopes (51V, 52Cr, 55Mn, 58,60Ni, 59Co, 63,65Cu, 64,66,68Zn, 75As, 78Se, 111,113Cd, 206,207,208Pb y 238U) in seawater. The method combined a simple and fast Al(OH)3 co-precipitation method, to pre-concentrate mineral elements and to separate them from the seawater matrix, and inductively coupled plasma mass spectrometry using the dynamic reaction cell with NH3 gas to do quantitative determinations free from polyatomic interferences. The recoveries of trace elements after Al(OH)3 co-precipitation varies between 80% for 111Cd and 116% f…
Analysis of currently used pesticides in fine airborne particulate matter (PM 2.5) by pressurized liquid extraction and liquid chromatography-tandem mass spectrometry.
During and after the application of currently used pesticides (CUPs) a significant fraction of applied pesticides can be lost to the air. A confirmatory and rapid procedure has been developed for the determination of four fungicides (carbendazim, thiabendazol, imazalil and bitertanol), three insecticides (imidacloprid, methidathion and pyriproxyfen), one helicide (methiocarb) and one acaricide (hexythiazox) in fine airborne particulate matter (PM 2.5) at trace level. The proposed method includes extraction of PM 2.5-bound pesticides by pressurized liquid extraction (PLE) followed by a direct injection into LC-MS/MS. The main parameters affecting the performance of the electrospray ionizatio…
Polyfurfuryl alcohol composite as adsorbent of polychlorinated biphenyls and pyrethroid insecticides
Abstract Composites from furfuryl alcohol and silica gel were prepared in dichloromethane using trifluoroacetic acid as catalyst and characterized by means of thermogravimetric analysis, transmission electron microscopy and nitrogen adsorption–desorption isotherms. The polymer content in the composites ranged between 19.5% and 32.9%. The capability to adsorb polychlorinated biphenyls and pyrethroid insecticides was tested for composite samples containing different percentages of polymer. Pyrethroids are retained almost totally by composites containing around 24–33% of polymer, while recovery of PCBs close to 80% is obtained with all the composites. No selectivity between compounds of the sa…
Long-term effect of temperature on bioaccumulation of dietary metals and metallothionein induction in Sparus aurata
Previous studies have demonstrated that the commercial feed of aquacultured fish contains trace amounts of toxic and essential metals which can accumulate in tissues and finally be ingested by consumers. Recently rising temperatures, associated to the global warming phenomenon, have been reported as a factor to be taken into consideration in ecotoxicology, since temperature-dependent alterations in bioavailability, toxicokinetics and biotransformation rates can be expected. Sparus aurata were kept at 22. °C, 27. °C and 30. °C for 3. months in order to determine the temperature effect on metallothionein induction and metal bioaccumulation from a non-experimentally contaminated commercial fee…
A passive sampling-based analytical strategy for the determination of volatile organic compounds in the air of working areas.
Abstract An analytical methodology based on the use of a polyethylene layflat tube filled with activated carbon and Florisil (ACFL-VERAM) was employed for the passive sampling of volatile organic compounds (VOCs) in the air of working areas of packing industries. VOCs amount in the ACFL-VERAM sampler was directly determined through head-space-gas chromatography–mass spectrometry (HS-GC–MS) allowing a direct determination in only 20 min without the need of any previous treatment. Uptake parameters, like sampling rate ( R S ) and sampler–air partition coefficient ( K SA ), were determined for every studied VOC from adsorption isotherm data. Additionally, experimental equations have been propo…
Cadmium induced metallothionein in hepatopancreas of Procambarus clarkii: Quantification by a silver-saturation method
Abstract 1. Cadmium induced metallothionein (MT) in crayfish hepatopancreas was measured by silver-saturation method. 2. An increase in MT content was recorded in crayfish hepatopancreas after 12 hr of exposure to 10 mg Cd/l. 3. There was found to be a linear relationship between MT concentrations in hepatopancreas and cadmium concentration in the water. 4. MT levels in hepatopancreas of 20 mg Cd/l exposed crayfish were 7-fold higher than those in control animals.
Occurrence of currently used pesticides in ambient air of Centre Region (France)
Ambient air samples were collected, from 2006 to 2008 at three rural and two urban sites in Centre Region (France) and analyzed for 56 currently used pesticides (CUPS), of which 41 were detected. The four CUPs most frequently detected were the herbicides trifluralin, acetochlor and pendimethalin and the fungicide chlorothalonil, which were found with frequencies ranging between 52 and 78%, and with average concentrations of 1.93, 1.32, 1.84 and 12.15 ng m(-3), respectively. Among the detected pesticides, concentrations of eight fungicides (spiroxamine, fenpropimorph, cyprodinil, tolyfluanid, epoxiconazole, vinchlozolin, fluazinam, fludioxinil), two insecticides (propargite, ethoprophos), an…
Use of semipermeable membrane devices for monitoring pesticides in indoor air.
Abstract In this work, 40 pesticides from different categories were analyzed in the air of 20 indoor places that have an intensive use of pesticides. Passive sampling was carried out by using semipermeable membrane devices (SPMDs) deployed for 7 days. SPMDs were analyzed using microwave-assisted extraction and GC/MS. PCB-195 was used as an internal standard. Recoveries ranged between 81 and 108 for many compounds, with RSD values &lt;11. Typical LOD values for 7 days of sampling were from 0.1 to 3.1 ng/m. Propamocarb, propoxur, carbosulfan, pirimicarb, metribuzin, metalaxyl, pendimethalin, oxadiazon, phenothrin, and permethrin were detected in 11 sampling sites, with air concentrations …
Use of semipermeable membrane devices for assessment of air quality in Tangier (Morocco)
Semipermeable membrane devices (SPMDs) have been used for the evaluation of the contamination of air in both the urban and the industrial area in Tangier (Morocco). Benzene, toluene, ethylbenzene a...
FT-Raman determination of Mepiquat chloride in agrochemical products
Abstract A fast and environmentally friendly procedure has been developed for Fourier transform Raman (FT-Raman) determination of a quaternary ammonium compound, Mepiquat chloride, in pesticide emulsifiable concentrate formulations. The method is based on the measurement of peak area values between 711 and 701 cm −1 corrected using a baseline defined at 620 cm −1 and interpolated in an external calibration of Mepiquat chloride standards dissolved in water. FT-Raman spectra were collected over 1.5 min from samples confined in screw cap standard chromatographic glass vials, at a nominal resolution of 4 cm −1 accumulating 25 scans per spectra and using a laser power of 1000 mW. Five commercial…
Green determination of the presence of volatile organic compounds in vehicle repair shops through passive sampling.
A simple, fast and green direct analytical methodology has been developed to evaluate the concentration level of volatile organic compounds (VOCs) in indoor areas of vehicle repair shops using membrane devices as passive samplers. VOCs retained in the samplers were directly determined without any sample pre-treatment and avoiding the use of solvents by head space (HS) coupled to gas chromatography-mass spectrometry (GC-MS) in only 20 min. Benzene, toluene, tetrachloroethene, m,p-xylene and o-xylene were found at concentration levels from 0.1 to 11.2 mg m(-3).
Development of a versatile, easy and rapid atmospheric monitor for benzene, toluene, ethylbenzene and xylenes determination in air
Abstract A new procedure for the passive sampling in air of benzene, toluene, ethylbenzene and xylene isomers (BTEX) is proposed. A low-density polyethylene layflat tube filled with a mixture of solid phases provided a high versatility tool for the sampling of volatile compounds from air. Several solid phases were assayed in order to increase the BTEX absorption in the sampler and a mixture of florisil and activated carbon provided the best results. Direct head-space-gas chromatography–mass spectrometry (HS-GC–MS) measurement of the whole deployed sampler was employed for a fast determination of BTEX. Absorption isotherms were used to develop simple mathematical models for the estimation of…
First-order derivative resolution of overlapped PAH peaks with common mass spectra in gas chromatography–mass spectrometry
Abstract First-order derivative of 15 points smoothed chromatograms of mixtures of benzo( b )fluoranthene (BbF) and benzo( k )fluoranthene (BkF) for the m / z 252 ion obtained using two microscans has been proposed as a simple alternative to the resolution of overlapped chromatographic peaks of these two compounds which have identical mass spectra. The procedure provides limits of detection of 12 and 29 ng g −1 for BbF and BkF, respectively and offers the possibility to use the 250 and 248 ions to confirm the identity of these analytes.
Development of a novel methodology for determination of dialkyl phosphates in human urine using liquid chromatography-tandem mass spectrometry
Abstract In this study a fast and sensitive method was developed for the quantitative determination of six dialkyl phosphates (DAPs) in human urine using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The proposed methodology was based on liquid-liquid extraction (LLE) with diethyl ether and ethyl acetate using MgSO4 and NaCl, followed by liquid chromatography and mass spectrometry detection in the selected reaction mode (SRM) with negative electrospray ionization (ESI-). Detection settings were optimized by design of experiments (DoE). Dibutyl phosphate (DBP) was used as internal standard. Several criteria established in the SANTE/11813/2017 guidance document for pesticide resi…
Determination of pyrethroid insecticide residues in vegetable oils by using combined solid-phases extraction and tandem mass spectrometry detection
Abstract A methodology has been developed for the determination of pyrethroid insecticide residues in vegetable oils, based in a solid-phase extraction (SPE) with combined solid supports phases. Several solid phases such as florisil, alumina, C18 and graphitized carbon black were tested in order to minimize fat residues, being a combination of treated alumina and C18 which provided the best results. Oil samples were partitioned with acetonitrile–hexane (1:1) and then eluted through a combined column packed with deactivated basic-alumina and C18, employing the acetonitrile extract as elution solvent. Gas chromatography tandem mass spectrometry was used for determination. Tetramethrin, Bifent…
Mineral soil composition interfacing archaeology and chemistry
Abstract In the last decade, different soil types have been analysed to evaluate the effect of human activities from an archaeological point of view. In particular, in the last few years, tremendous advances have been made in sample preparation and analytical methods used in archaeological soil analyses. However, there is still a need to set standardized protocols to achieve different archaeological goals. Therefore, in this study, the analytical methods available to study archaeological soils have been reviewed together with a critical discussion on the challenging archaeological questions, which could be answered by determining their mineral composition. Data on trace elements and rare ea…
Fast environmental impact assessment through ICP-MS: application to bivalves from a tropical estuary (Pina Bay, Recife, Brazil)
Validated, non-destructive and environmentally friendly determination of cocaine in euro bank notes.
A non-destructive, fast and environmentally friendly procedure has been developed for cocaine determination in euro bank notes. Cocaine was extracted with 15 ml methanol by vortex agitation during 5 min. The extract was evaporated and reconstituted in 0.5 ml methanol. GC-MS-MS analysis was performed using as precursor ion m/z 182.2, with an excitation energy voltage of 1.60 eV, being the product ions measured m/z 150.2 and 82.0. A limit of detection of 0.15 ng per note and a repeatability of 6%, established from the relative standard deviation, of a 1 ng ml(-1) level, were achieved. Recoveries of 101+/-2 and 98+/-3% were obtained for samples spiked with 100 and 10 microg respectively. Resul…
Capillary column gas chromatographic identification of sugars in honey as trimethylsilyl derivatives.
A method for identifying carbohydrates (mono-, di- and trisaccharides) in honey is presented. It is based on the separate preparation of both trimethylsilyl ethers and oxime trimethylsilyl ethers of the sugars followed by their gas chromatographic separation on a fused-silica capillary column coated with OV-101 using temperature programming. From the two chromatograms, the number of peaks given by each derivatized sugar, their relative retention times and peak-area ratios are used for identification. The identities of two unidentified trisaccharide peaks are considered. Quantitative applications to honey sugar analysis are discussed.
Determination of four parabens and bisphenols A, F and S in human breast milk using QuEChERS and liquid chromatography coupled to mass spectrometry
Abstract For the first time, a multiresidue, sensitive and high throughput method for determination of bisphenol A, F and S and 4 parabens (methyl paraben, ethyl paraben, propyl paraben and butyl paraben) in human breast milk was developed. The proposed method includes an extraction and clean-up procedure based on QuEChERS methodology followed by liquid chromatography coupled to triple quadrupole mass spectrometry determination. Negative atmospheric pressure chemical ionization in the selected reaction monitoring mode was used for mass detection. During the method validation the recoveries varied between 83 and 115% with a precision lower than 20% for all analytes using spiked levels from 0…
Determination of chromium(III) and chromium(VI) in mineral water by bidirectional electrostacking and electrothermal atomic absorption spectrometry
Abstract A feasibility investigation was carried out on the use of bidirectional electrostacking for simultaneous separation and pre-concentration of Cr(III) and Cr(VI) and their electrothermal atomic absorption spectrometry (ETAAS) determination. The bidirectional electrostacking manifold was improved, and the effects of sample tube cross-section and electrostacking time on the pre-concentration factor were investigated. Results indicate that the sample tube cross-section and electrostacking time are the main influence factors on the electrostacking pre-concentration, as well as the electric field strength and ionic mobility. The method developed was suitable for the simultaneous separatio…
Development of a method for the analysis of seven banned azo-dyes in chilli and hot chilli food samples by pressurised liquid extraction and liquid chromatography with electrospray ionization-tandem mass spectrometry
An automated, confirmatory and sensitive procedure has been developed and validated for the determination of Sudan (I-IV), Sudan Orange G, Sudan Red 7B and Para Red in hot chilli food samples. The proposed method includes pressurised liquid extraction (PLE) with acetone, gel permeation chromatography (GPC) clean-up and detection by liquid chromatography (LC) coupled to electrospray ionization in positive mode tandem mass spectrometry (ESI-MS-MS). The main parameters affecting the performance of the different ionization sources and PLE parameters were previously optimised using statistical design of experiments (DOE). The method was in-house validated on chilli powder and chilli meat. Linear…
Decoration composition of Iberian Iron Age ivory artifacts identified by no-destructive chemical analyses
Se analizan mediante análisis no destuctivos 5 mangos de marfil con decoración incrustada. Se detecta ámbar y estaño. In this work, five unique Iberian Iron Age handles have been studied. The use of portable X-ray fluorescence (pXRF) and Fourier transform near–infrared (FT-NIR) spectroscopy no-destructive techniques has allowed us to identify two raw materials (amber and tin) used to decorate the ivory handles.Due to the finesse of their inlaid decoration and the value and exoticismof thematerial employed for their manufacture, these ivory objects are really exceptional Iberian archaeology findings. Interestingly, it has been possible to determine that tin was used as an adherentmaterial to…
Microwave-assisted extraction of pyrethroid insecticides from semi permeable membrane devices (SPMDs) used to indoor air monitoring
Abstract A rapid and environmentally friendly methodology was developed for the extraction of pyrethroid insecticides from semi permeable membrane devices (SPMDs), in which they were preconcentrated in gas phase. The method was based on gas chromatography mass–mass spectrometry determination after a microwave-assisted extraction, in front of the widely employed dialysis method. SPMDs were extracted twice with 30 mL hexane:acetone, irradiated with 250 W power output, until 90 °C in 10 min, this temperature being held for another 10 min. Clean-up of the extracts was performed by acetonitrile–hexane partitioning and solid-phase extraction (SPE) with a combined cartridge of 2 g basic-alumina, d…
Determination of ultratrace bismuth in milk samples by atomic fluorescence spectrometry.
Abstract A sensitive procedure was developed for determination of bismuth (Bi) in milk samples by hydride generation atomic fluorescence spectrometry (HG–AFS) after microwave-assisted sample digestion with HNO3 and H2O2. The method provides a sensitivity of 1832 fluorescence units (ng/mL) with a detection limit of 0.01 ng/mL, which corresponds to 20 pg absolute limit of detection, equivalent to 0.50 ng/g in the original sample. Application of the methodology to cow milk samples from the Spanish market showed the presence of Bi at a concentration of 11.8–28.8 ng/g, which compared well with data obtained after dry ashing of samples and with data obtained by inductively coupled plasma–mass spe…
Uptake and bioavailability of persistant organic pollutants by plants grown in contaminated soil
This paper assesses the uptake of persistent organic pollutants (POP's) into plants. In particular, uptake of alpha-endosulfan, beta-endosulfan and endosulfan sulfate from lettuce. The lettuce plants were grown on compost that had previously been contaminated at 10 and 50 microg g(-1) per POP. The soil was slurry spiked by adding the appropriate amount of POP in acetone in an approximate ratio of 1 ratio 2, w/v soil ratio solvent. The solvent was left to evaporate at ambient temperature for 24 hours. Lettuce plants were grown under artificial daylight for 12 hours a day. The influence of soil ageing on the recovery of POP's from spiked soil samples was also assessed. The average recovery of…