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1.
BMC Cardiovasc Disord ; 23(1): 13, 2023 01 12.
Article En | MEDLINE | ID: mdl-36635626

BACKGROUND: Right ventricular (RV) dysfunction in patients with non-ischemic dilated cardiomyopathy (NICM) is associated with cardiovascular events. To analyze the feasibility of assessing RV myocardial deformation by feature tracking (FT)-cardiac magnetic resonance (CMR), and its usefulness as a prognostic marker. METHODS: Retrospective study of NICM patients undergoing CMR. Longitudinal FT-RV free wall (LFT-RVFW) and fractional area change (FAC) were obtained. Correlation with standard RV parameters was studied. An association with combined event (heart failure (HF), ICD implantation or cardiovascular death) was assessed using a logistic regression model. RESULTS: 98 patients (64 ± 13 years) were included. Left ventricular (LV) systolic function (LVEF 29.5 ± 9.6%, 47% with LVEF ≥ 30%) and RV (RVEF 52.2 ± 14.6%, 72% with RVEF ≥ 45%). Follow-up of 38 ± 17 months, 26.5% presented at least one admission for HF. An excellent correlation of LFT-RVFW (r = 0.82) and FAC (r = 0.83) with RVEF was evident. No association of RV-FT parameters with prognosis entire study population was found. However, in patients with LVEF ≥ 30%, admissions for HF were associated with lower LFT-RVFW (-21.6 ± 6.6% vs -31.3 ± 10%; p = 0.006) and FAC (36.6 ± 9.6% vs 50.5 ± 13.4%; p < 0.001) values. Similar differences were observed when only patients with RVEF ≥ 45% were considered. An LFT-RVFW cut-off point of -19.5% and FAC of 36.5% showed good prognostic performance. Decreased LFT-RVFW or FAC represented an independent predictor of combined event in patients with LVEF ≥ 30%. CONCLUSIONS: In NICM patients without severe LV dysfunction, decreased values of LFT-RVFW and/or FAC were associated with HF admissions, independently of RVEF.


Cardiomyopathy, Dilated , Heart Failure , Ventricular Dysfunction, Right , Humans , Retrospective Studies , Magnetic Resonance Imaging, Cine , Ventricular Dysfunction, Right/diagnostic imaging , Ventricular Dysfunction, Right/etiology , Cardiomyopathy, Dilated/diagnostic imaging , Magnetic Resonance Spectroscopy , Ventricular Function, Right , Stroke Volume
2.
Anal Chim Acta ; 1142: 179-188, 2021 Jan 15.
Article En | MEDLINE | ID: mdl-33280695

Most of the plastics produced worldwide are finally disposed into the environment, most of them being one-use plastic packaging. Once released, plastics may undergone degradation through several agents, such as solar radiation, mechanical forces, and microbial action. Weathered plastics and microplastics (MPs) collected from the marine environment show considerable physical and chemical differences regarding their pristine counterparts; most notably on their surface, where spectrometric measurements are done. Hence, it is crucial to consider aging for their correct identification and quantification in environmental monitoring. Five of the most common polymers employed worldwide for packaging (LDPE, HDPE, PS, PP and PET) were weathered in a pilot-scale system simulating dry and marine conditions for more than 10 weeks. Aliquots were withdrawn periodically to monitor their weathering processes by means of infrared spectrometry and scanning electron microscopy; their spectra were compared and band ratios calculated. Results showed that an individual study of each polymer is necessary since degradation pathways and products depend on the polymer type. Moreover, including spectra of weathered polymers in the spectral libraries to obtain reliable identifications in microplastics pollution studies was critical.

3.
J Hazard Mater ; 381: 120949, 2020 01 05.
Article En | MEDLINE | ID: mdl-31387076

In this study we evaluated a new type of passive air sampler, the "mossphere" device, filled with a Sphagnum palustre clone. For this purpose, we compared the atmospheric levels of polyaromatic hydrocarbons (PAHs) collected using this device and those collected in conventional bulk deposition and particulate matter (PM10) samplers. All three types of samplers were exposed at 10 sites affected by different levels of pollution and located in two different climate zones. The bulk deposition/ mossphere comparison yielded a greater number of significant regressions with higher coefficients of determination than the PM10/ mossphere comparison. No significant regressions were observed for 3-ring PAHs in either comparison. The mosspheres explain ca. 50% of the variability of the concentrations of 4-, 5- and 6-ring PAHs and total PAHs detected in PM10 and ca. 70% of the corresponding concentrations detected in the bulk deposition. The use of the Sphagnum clone enables standardization of the set-up, thus making the mossphere device a good sampling tool for monitoring 4-, 5- and 6-ring and total PAHs, especially those associated with bulk deposition. The findings indicate the potential usefulness of this innovative technology for mapping PAH levels.


Air Pollutants/analysis , Environmental Monitoring/instrumentation , Polycyclic Aromatic Hydrocarbons/analysis , Sphagnopsida , Air Pollution/analysis
4.
Environ Pollut ; 249: 767-775, 2019 Jun.
Article En | MEDLINE | ID: mdl-30951960

The spatial and temporal distribution of selected endocrine disrupting compounds (4-tert-octylphenol, 4-n-octylphenol, 4-n-nonylphenol, nonylphenol, and bisphenol A) in two coastal areas of the Iberian Peninsula (Ria de Vigo and Mar Menor lagoon) were evaluated for the first time. Seawater and sediment samples collected during spring and autumn of 2015 were analysed using greener extraction techniques and liquid chromatography-tandem mass spectrometry. The presence of branched isomers (4-tert-octylphenol and nonylphenol) and bisphenol A in almost all seawater and sediment samples demonstrated their importance as pollutants in the frame of water policy, while no concentrations of linear isomers (4-n-octylphenol and 4-n-nonylphenol) were found. Higher seawater levels were observed in Mar Menor lagoon, especially in spring, associated with wastewater treatment plant effluents and nautical, agricultural and industrial activities. Similar sediment concentrations were measured in both studied areas, being nonylphenol levels five times higher than those measured for the other EDCs. Experimental sediment-water partition coefficients showed a moderate sorption of target compounds to sediments. Risk quotients for water compartment evidenced a moderate risk posed by nonylphenol, considering the worst-case scenario. For sediments, moderate risk related to 4-tert-octylphenol and high risk to nonylphenol were estimated.


Endocrine Disruptors/analysis , Geologic Sediments/chemistry , Seawater/chemistry , Water Pollutants, Chemical/analysis , Environmental Monitoring , Risk Assessment , Seasons , Wastewater/chemistry
5.
Anal Chim Acta ; 1024: 39-51, 2018 Sep 18.
Article En | MEDLINE | ID: mdl-29776546

The problem of endocrine disrupting compounds (EDCs) in the environment has become a worldwide concern in recent decades. Besides their toxicological effects at low concentrations and their widespread use in industrial and household applications, these pollutants pose a risk for non-target organisms and also for public safety. Analytical methods to determine these compounds at trace levels in different matrices are urgently needed. This review critically discusses trends in analytical methods for well-known EDCs like alkylphenols and bisphenol A in solid environmental matrices, including sediment and aquatic biological samples (from 2006 to 2018). Information about extraction, clean-up and determination is covered in detail, including analytical quality parameters (QA/QC). Conventional and novel analytical techniques are compared, with their advantages and drawbacks. Ultrasound assisted extraction followed by solid phase extraction clean-up is the most widely used procedure for sediment and aquatic biological samples, although softer extraction conditions have been employed for the latter. The use of liquid chromatography followed by tandem mass spectrometry has greatly increased in the last five years. The majority of these methods have been employed for the analysis of river sediments and bivalve molluscs because of their usefulness in aquatic ecosystem (bio)monitoring programs. Green, simple, fast analytical methods are now needed to determine these compounds in complex matrices.


Benzhydryl Compounds/analysis , Chemistry Techniques, Analytical/trends , Endocrine Disruptors/analysis , Phenols/analysis , Soil Pollutants/analysis , Solid Phase Extraction/trends , Animals , Bivalvia/chemistry , Geologic Sediments/analysis , Humans , Ultrasonic Waves , Water Pollutants, Chemical/analysis
6.
J Chromatogr A ; 1520: 35-47, 2017 Oct 20.
Article En | MEDLINE | ID: mdl-28918855

An in-tube solid phase microextraction, coupled with high-performance liquid chromatography with diode array detection (IT-SPME-HPLC-DAD) method, has been developed for the simultaneous determination of 13 diesters (from dimethyl to dioctylphthalate plus diisobutyl, benzylbutyl, di-2-ethylhexyl, diisononyl and diisodecylphthalate) and 2 monoesters of phthalic acid (mono-butyl and mono-(2-ethylhexyl) phthalate) in particulate matter (PM10). Triethylamine at pH=3 was used as an ion-pair reagent with a double function, of regulating the chromatographic retention of the monoesters and the most hydrophilic diesters on a monolithic silica column, and of improving their extraction on a porous polymer with divinylbenzene-4-vinylpyridine capillary. The chromatographic separation was achieved in 13min. A previous ultrasound-assisted extraction from PM10filters was also optimized using methanol as solvent. The method detection limits were 0.09-0.52ngm-3, the inter-day precision at concentration of 20ngmL-1 was between 4.2% and 12.7% (n=15), and the average recovery was 87.3%. The average absolute IT-SPME recovery was 26.2% and the linear range reached up to 109ngm-3 for most analytes. The method was applied to PM10 samples from different environments collected in Galicia (Spain). DiBP was the major phthalate, followed by its isomer DnBP in urban sites and by DEP in the suburban area. In all samples, DEHP quantified correlates with the isomers of dibutylphthalate. Total PAE concentration was between 14.5 and 245.5ngm-3. To the best of our knowledge, this is the first time that a method allows the simultaneous determination of 13 phthalates and their degradation products in particulate matter.


Air Pollutants/analysis , Environmental Monitoring/methods , Particulate Matter/chemistry , Phthalic Acids/analysis , Solid Phase Microextraction , Chromatography, High Pressure Liquid , Limit of Detection , Spain
7.
Environ Pollut ; 225: 323-328, 2017 Jun.
Article En | MEDLINE | ID: mdl-28262376

Although a large body of literature exists on the use of transplanted mosses for biomonitoring of air pollution, no article has addressed so far the use and the accumulation performance of a cloned moss for this purpose. In this work, a direct comparison of metal accumulation between bags filled with a Sphagnum palustre L. clone or with native Pseudoscleropodium purum Hedw., one of the most used moss species in biomonitoring surveys, was investigated. The test was performed in sites with different atmospheric contamination levels selected in urban, industrial, agricultural and background areas of Italy and Spain. Among the eighteen elements investigated, S. palustre was significantly enriched in 10 elements (Al, Ba, Cr, Cu, Fe, Hg, Pb, Sr, V and Zn), while P. purum was enriched only in 6 elements (Al, Ba, Cu, Hg, Pb and Sr), and had a consistently lower uptake capacity than S. palustre. The clone proved to be more sensitive in terms of metal uptake and showed a better performance as a bioaccumulator, providing a higher accumulation signal and allowing a finer distinction among the different land uses and levels of pollution. The excellent uptake performance of the S. palustre clone compared to the native P. purum and its low and stable baseline elemental content, evidenced in this work, are key features for the improvement of the moss bag approach and its large scale application.


Air Pollutants/analysis , Bryopsida/physiology , Environmental Monitoring/methods , Sphagnopsida/physiology , Air Pollution/statistics & numerical data , Bryophyta , Bryopsida/chemistry , Italy , Mercury , Metals/analysis , Spain , Sphagnopsida/chemistry
8.
Anal Chim Acta ; 962: 1-14, 2017 04 15.
Article En | MEDLINE | ID: mdl-28231873

In the last decade, the impact of alkylphenols and bisphenol A in the aquatic environment has been widely evaluated because of their high use in industrial and household applications as well as their toxicological effects. These compounds are well-known endocrine disrupting compounds (EDCs) which can affect the hormonal system of humans and wildlife, even at low concentrations. Due to the fact that these pollutants enter into the environment through waters, and it is the most affected compartment, analytical methods which allow the determination of these compounds in aqueous samples at low levels are mandatory. In this review, an overview of the most significant advances in the analytical methodologies for the determination of alkylphenols and bisphenol A in waters is considered (from 2002 to the present). Sample handling and instrumental detection strategies are critically discussed, including analytical parameters related to quality assurance and quality control (QA/QC). Special attention is paid to miniaturized sample preparation methodologies and approaches proposed to reduce time- and reagents consumption according to Green Chemistry principles, which have increased in the last five years. Finally, relevant applications of these methods to the analysis of water samples are examined, being wastewater and surface water the most investigated.


Benzhydryl Compounds/analysis , Chemistry Techniques, Analytical/trends , Phenols/analysis , Water/chemistry , Analytic Sample Preparation Methods , Benzhydryl Compounds/chemistry , Humans , Phenols/chemistry , Quality Control
9.
Chemosphere ; 175: 52-65, 2017 May.
Article En | MEDLINE | ID: mdl-28211335

Six phthalic acid esters were determined in rainwater samples, from which a very low sample volume was collected. This method combines on-line in-tube solid-phase microextraction coupled to high-performance liquid chromatography with a diode-array detector. In order to obtain a short analysis time and to reduce the consumption of organic solvents, two chromatographic phases (C18 monolithic and cyanopropyl silica) are compared. Although three critical pairs are found, faster separation, good resolution and lower pressures are achieved using C18 monolithic column. In order to achieve a simple and sensitive method, two commercial capillaries (a porous polymer with divinylbenzene-4-vinylpyridine and a liquid-phase capillary with 95% poly(dimethylsiloxane)-5% poly(diphenylsiloxane)) are tested for the extraction process. Due to great differences of hydrophobicity among the six phthalates, the selection of a modifier is necessary for a good extraction. The best conditions are achieved using 5 mL of sample containing 40% methanol in a 70 cm-long porous polymer capillary. The procedural blanks are controlled and taken into account in the calculation of the detection limits. Except for dimethylphthalate, the method detection limits are in the range from 0.2 to 0.9 ng mL-1 and the inter-day precision is between 5.3% and 12.5%. The recoveries were within the range of 71%-101%. Rainwater samples are analyzed in order to examine the dilution effect and washout of phthalates in the atmosphere. Dibutyl phthalate is the predominant phthalate found and di-(2-ethylhexyl) phthalate is detected in all analyzed samples.


Chromatography, High Pressure Liquid/methods , Phthalic Acids/analysis , Rain/chemistry , Solid Phase Microextraction/methods , Dibutyl Phthalate/analysis , Esters/analysis , Limit of Detection
10.
Talanta ; 162: 648-653, 2017 Jan 01.
Article En | MEDLINE | ID: mdl-27837884

In this work, a new reliable, simple and fast method for the determination of six PAEs in sediments, based on ultrasonic solvent extraction (USE) followed by head space solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry determination (GC-MS), is proposed. The extraction parameters were studied, and the most favourable conditions were selected. The analytical features of the method were calculated: matrix effect, accuracy (ranged from 90% to 111%), repeatability and intermediate precision (RSD <10%), detection and quantification limits of the method (ranged from 0.001µgg-1 (DOP) to 0.142µgg-1 (DEP)), and satisfactory results were obtained. Major advantages of this approach are low consumption of reagents and solvents, no clean-up or evaporation steps were required and minimum sample manipulation. In addition, cross contamination from glassware, solvents and samples is minimized, thus procedural blanks are keeping to a minimum.. The applicability of the proposed method was demonstrated analysing sediment samples from Galician coast (NW Spain). The proposed method allows the application in routine laboratory conditions and its implementation in environmental monitoring studies under the European Water Framework Directive (WFD) and Marine Strategy Framework Directive (MSFD).

11.
Talanta ; 155: 175-84, 2016 08 01.
Article En | MEDLINE | ID: mdl-27216671

A novel single-step method was developed for the determination of 15 polycyclic aromatic hydrocarbons (PAHs) at ultratrace levels in rainwater by on-line in-tube solid-phase microextraction (IT-SPME) coupled to high-performance liquid chromatography-photodiode array-fluorescence detection. This paper is focused on a study of the IT-SPME coupling and optimization, its application to rainwater and other environmental waters and the stability of PAH rainwater solutions. In order to solve the different extractive behavior of PAHs, several IT-SPME parameters were optimized, with the type and percentage of organic modifier playing a decisive role. In the kinetic study on stability of PAH solutions, the organic modifier has proven to be effective as a preservative, avoiding the loss of the higher-molecular weight PAHs. The proposed method presents a wide interval of linearity (10-1500ngL(-1)) and a good relative standard deviation between 3.4% and 14.6% for the PAHs analyzed. Detection and quantification limits between 2.3 and 28ngL(-1) and 5.7 and 65ngL(-1) were obtained respectively, taking into account the values of the procedure blanks. Recoveries for different kinds of real water samples were within the range of 72-110%. Low and medium-molecular weight PAHs predominate in daily and monthly rainwater samples analyzed. In comparison with other methods reported, the proposed method achieves a significant reduction of the sample volume, the organic solvent consumption and time of sample treatment, allowing a cost-effective analysis of environmental waters. The method is especially suitable for samples from the precipitation events of low intensity or short duration for which sample volume is limiting.

12.
Talanta ; 153: 130-7, 2016 06 01.
Article En | MEDLINE | ID: mdl-27130099

Due to the complexity and heterogeneity of plant matrices, new procedure should be standardized for each single biomonitor. Thus, here is described a matrix solid-phase dispersion extraction method, previously used for moss samples, improved and modified for the analyses of PAHs in Quercus robur leaves and Pinus pinaster needles, species widely used in biomonitoring studies across Europe. The improvements compared to the previous procedure are the use of Florisil added with further clean-up sorbents, 10% deactivated silica for pine needles and PSA for oak leaves, being these matrices rich in interfering compounds, as shown by the gas chromatography-mass spectrometry analyses acquired in full scan mode. Good trueness, with values in the range 90-120% for the most of compounds, high precision (intermediate precision between 2% and 12%) and good sensitivity using only 250mg of samples (limits of quantification lower than 3 and 1.5ngg(-1), respectively for pine and oak) were achieved by the selected procedures. These methods proved to be reliable for PAH analyses and, having advantage of fastness, can be used in biomonitoring studies of PAH air contamination.


Pinus , Quercus , Environmental Monitoring , Europe , Plant Leaves , Polycyclic Aromatic Hydrocarbons
13.
Mar Pollut Bull ; 106(1-2): 360-5, 2016 May 15.
Article En | MEDLINE | ID: mdl-27001713

Wild mussels (Mytilus galloprovincialis) were selected as bioindicators of chemical pollution to evaluate the occurrence and spatial distribution of five endocrine disrupting compounds in the Spanish Atlantic coast and Bay of Biscay. A total of 24 samples were collected in May, 2011 and analysed by selective pressurized liquid extraction followed by liquid chromatography tandem mass spectrometry determination. Branched alkylphenols (4-tert-octylphenol and nonylphenol) were determined in more than 90% of the analysed samples whereas the presence of linear alkylphenols (4-n-octylphenol and 4-n-nonylphenol) was scarcely detected (<12% of the samples). Wastewater treatment plants discharges and nautical, fishing and shipping activities were considered the primary sources of contamination by alkylphenols. Bisphenol A was found in 16% of the analysed samples associated to punctual industrial discharges. A total endocrine disrupting compound (alkylphenols and bisphenol A) average concentration of 604ngg(-1) dw was calculated and nonylphenol was the main contributor in almost all sampling points.


Bays/chemistry , Benzhydryl Compounds/analysis , Endocrine Disruptors/analysis , Environmental Monitoring/methods , Mytilus/drug effects , Phenols/analysis , Water Pollutants, Chemical/analysis , Animals , Mytilus/chemistry , Spain , Wastewater/analysis
14.
Anal Chim Acta ; 906: 41-57, 2016 Feb 04.
Article En | MEDLINE | ID: mdl-26772124

In-tube solid-phase microextraction (in-tube SPME or IT-SPME) is a sample preparation technique which has demonstrated over time its ability to couple with liquid chromatography (LC), as well as its advantages as a miniaturized technique. However, the in-tube SPME perspectives in the forthcoming years depend on solutions that can be brought to the environmental, industrial, food and biomedical analysis. The purpose of this scoping review is to examine the strengths and weaknesses of this technique during the period 2009 to 2015 in order to identify research gaps that should be addressed in the future, as well as the tendencies that are meant to strengthen the technique. In terms of methodological aspects, this scoping review shows the in-tube SPME strengths in the coupling with LC (LC-mass spectrometry, capillary LC, ultra-high-pressure LC), in the new performances (magnetic IT-SPME and electrochemically controlled in-tube SPME) and in the wide range of development of coatings and capillaries. Concerning the applicability, most in-tube SPME studies (around 80%) carry out environmental and biomedical analyses, a lower number food analyses and few industrial analyses. Some promising studies in proteomics have been performed. The review makes a critical description of parameters used in the optimization of in-tube SPME methods, highlighting the importance of some of them (i.e. type of capillary coatings). Commercial capillaries in environmental analysis and laboratory-prepared capillaries in biomedical analysis have been employed with good results. The most consolidated configuration is in-valve mode, however the cycle mode configuration is frequently chosen for biomedical analysis. This scoping review revealed that some aspects such as the combination of in-tube SPME with other sample treatment techniques for the analysis of solid samples should be developed in depth in the near future.


Solid Phase Microextraction/methods , Chromatography, Liquid , Mass Spectrometry
15.
Sci Total Environ ; 529: 121-30, 2015 Oct 01.
Article En | MEDLINE | ID: mdl-26005755

The occurrence, distribution and bioaccumulation of five endocrine disrupting compounds (4-tert-octylphenol, 4-n-octylphenol, 4-n-nonylphenol, nonylphenol and bisphenol A) in water, sediment and biota (Corbicula fluminea) collected along the Minho River estuary (NW Iberian Peninsula) were examined. Samples were collected in two campaigns (May and November, 2012) and analyzed by different extraction procedures followed by liquid chromatography tandem mass spectrometry determination. The presence of linear isomers (4-n-octylphenol and 4-n-nonylphenol) was scarcely observed whereas branched isomers (4-tert-octylphenol and nonylphenol) were measured in almost all samples. Wastewater treatment plant effluents and nautical, fishing and agricultural activities are considered the primary source of pollution of the river by alkylphenols. The presence of bisphenol A in the river could be mainly associated to punctual sources of contamination from industrial discharges. A decrease in the total concentration of phenolic compounds in water was observed from spring to autumn (from 0.888 µg L(-1) in May to 0.05 µg L(-1) in November), while similar values were shown in C. fluminea samples from the two campaigns (1388 and 1228 ng g(-1) dw in spring and autumn, respectively). In sediments, the total concentration of the target compounds varied between 13 and 4536 ng g(-1) dw (average of 1041 ng g(-1) dw). Sediment-water partition coefficient (Kd), bioaccumulation factor (BAF) and biota-sediment accumulation factor (BSAF) were estimated and highest values were obtained for nonylphenol. Calculated risk quotients showed low and moderate risk for the aquatic environment from the presence of the target compounds at all sampling points. The estimation of the daily intake of the studied compounds via water and biota ingestion indicated no risk for human health.


Endocrine Disruptors/analysis , Environmental Monitoring , Water Pollutants, Chemical/analysis , Animals , Aquatic Organisms/metabolism , Biota , Endocrine Disruptors/metabolism , Fishes/metabolism , Geologic Sediments/chemistry , Rivers/chemistry , Spain , Water Pollutants, Chemical/metabolism
16.
J Chromatogr A ; 1383: 8-17, 2015 Feb 27.
Article En | MEDLINE | ID: mdl-25638263

A novel and Green analytical methodology for the determination of alkylphenols (4-tert-octylphenol, 4-n-octylphenol, 4-n-nonylphenol, nonylphenol) in sediments was developed and validated. The method was based on pressurized hot water extraction (PHWE) followed by miniaturized membrane assisted solvent extraction (MASE) and liquid chromatography-electrospray ionization tandem mass spectrometry detection (LC-ESI-MS/MS). The extraction conditions were optimized by a Plackett-Burman design in order to minimize the number of assays according to Green principles. Matrix effect was studied and compensated using deuterated labeled standards as surrogate standards for the quantitation of the target compounds. The analytical features of the method were satisfactory: relative recoveries varied between 92 and 103% and repeatability and intermediate precision were <9% for all compounds. Quantitation limits of the method (MQL) ranged from 0.061 (4-n-nonylphenol) to 1.7ngg(-1) dry weight (nonylphenol). Sensitivity, selectivity, automaticity and fastness are the main advantages of the exposed methodology. Reagent consumption, analysis time and waste generation were minimized. The "greenness" of the proposed method was evaluated using an analytical Eco-Scale approach and satisfactory results were obtained. The applicability of the proposed method was demonstrated analysing sediment samples of Galicia coast (NW of Spain) and the ubiquity of alkylphenols in the environment was demonstrated.


Chemistry Techniques, Analytical/methods , Geologic Sediments/chemistry , Hot Temperature , Phenols/analysis , Pressure , Water Pollutants, Chemical/analysis , Water/chemistry , Chromatography, High Pressure Liquid , Green Chemistry Technology , Liquid-Liquid Extraction , Miniaturization , Phenols/isolation & purification , Spectrometry, Mass, Electrospray Ionization , Water Pollutants, Chemical/isolation & purification
17.
J Chromatogr A ; 1385: 85-93, 2015 Mar 13.
Article En | MEDLINE | ID: mdl-25678317

The European Union Water Framework Directive (2013/39/EU) sets very restrictive environmental quality standards for 45 priority substances and other pollutants, including organotin compounds (OTCs). Therefore, it is necessary to develop analytical methods in compliance with the environmental quality standard (EQSs) proposed to protect the aquatic environment and humans. The proposed method (HS-SPME-GC-QqQ-MS/MS) allows the determination of OTCs, i.e. monobutyltin (MBT), dibutyltin (DBT) and TBT in water in the range of few ng L(-1). The method is nearly full automated, sensitive and simple; it involves less reagents, reduces waste, and is less-time consuming than traditional methods for OTCs. As such, the procedure connects with the principles of green analytical chemistry. Additionally, good precision (RSD<20%), a very low method quantification limit (MQL) (0.76 ng L(-1) for TBT by using only 10 mL of sample) and excellent linearity (range MQL-20 ng L(-1)) are achieved. Under these conditions, the very restrictive limits for the environmental quality standards (EQS) fixed by the 2013/39/EU Directive are achieved.


Environmental Monitoring/methods , Gas Chromatography-Mass Spectrometry , Organotin Compounds/analysis , Solid Phase Microextraction , Water Pollutants, Chemical/analysis , Water/chemistry , European Union
18.
Chemosphere ; 131: 241-7, 2015 Jul.
Article En | MEDLINE | ID: mdl-25648473

The occurrence and spatial distribution of alkylphenols (4-tert-octylphenol, 4-n-octylphenol, 4-n-nonylphenol, nonylphenol) and bisphenol A were examined in five estuaries along the Northwest coastal area of Spain. As far as we know, no previous works about this topic could be found in the literature. A total of 98 seawater samples were collected during May 2011-July 2012 and analyzed by a highly sensitive DLLME-LC-MS/MS methodology recently developed. Results indicated nonylphenol was the most ubiquitous compound with maximal concentration of 0.337 µg L(-1) (Ría de Vigo). The environmental quality standards (EQS) established in Directive 2013/39/EU for 4-tert-octylphenol were slightly exceeded in some sampling points. Fishing harbours, water treatment plant and industrial discharges were supposed as the main sources of contamination. Low and medium ecological risk was determined in all estuaries. Possible endocrine effects on biota and population were estimated in terms of estrogenic activity and daily intake respectively, and no risk was found in any case.


Endocrine Disruptors/analysis , Estuaries , Benzhydryl Compounds/analysis , Ecological Parameter Monitoring , Ecology , Endocrine Disruptors/adverse effects , Environmental Monitoring , Humans , Phenols/analysis , Seawater , Spain , Tandem Mass Spectrometry , Water Pollutants, Chemical/analysis , Water Purification
19.
Sci Total Environ ; 512-513: 114-124, 2015 Apr 15.
Article En | MEDLINE | ID: mdl-25616227

This work studies airborne quality in a geographical area that has not been investigated broadly: a suburban site nearby A Coruña (Galicia, NW Iberian Peninsula). In contrast to major Spanish cities, the site has Atlantic characteristics: rainy, scarce calm weather and infrequent prolonged sunny periods. The relationships between several gaseous pollutants (NO, NO2, NOx, CO, O3, PM10, PM2.5 and PM1) and their temporal trends (daily, monthly and seasonal) were evaluated. The aim was to unravel whether medium- and long-distance sources were impacting upon the site. Univariate studies focused on factorizing the pollutants according to a codifying factor (wind direction, hour of the day, season and month). Multivariate studies (Varimax-rotated factorial analysis) were done separately on both weekdays and weekends. The intensity of the daily maxima for NO, NO2, NOx and CO was lower during the weekends, with O3 behaving opposite. PM average values agreed with previous historical reports for a rural background station relatively close to the site and they decreased daily between 11:00 and 19:00 h, likely because of the marine breeze. With moderate wind speeds the pollutants were associated to medium-distance pollution sources, mainly the city of A Coruña and a combination of industrial pollution sources (a power plant, a solid waste incinerator and a regional airport).


Environmental Monitoring , Environmental Pollutants/analysis , Environmental Pollution/statistics & numerical data , Cities/statistics & numerical data , Spain
20.
Anal Chim Acta ; 852: 112-20, 2014 Dec 10.
Article En | MEDLINE | ID: mdl-25441887

A less time-, solvent- and sorbent-consuming analytical methodology for the determination of bisphenol A and alkylphenols (4-tert-octylphenol, 4-octylphenol, 4-n-nonylphenol, nonylphenol) in marine sediment was developed and validated. The method was based on selective pressurized liquid extraction (SPLE) with a simultaneous in cell clean up combined with liquid chromatography-electrospray ionization tandem mass spectrometry in negative mode (LC-ESI-MS/MS). The SPLE extraction conditions were optimized by a Plackett-Burman design followed by a central composite design. Quantitation was performed by standard addition curves in order to correct matrix effects. The analytical features of the method were satisfactory: relative recoveries varied between 94 and 100% and repeatability and intermediate precision were <6% for all compounds. Uncertainty assessment of measurement was estimated on the basis of an in-house validation according to EURACHEM/CITAC guide. Quantitation limits of the method (MQL) ranged between 0.17 (4-n-nonylphenol) and 4.01 ng g(-1) dry weight (nonylphenol). Sensitivity, selectivity, automaticity and fastness are the main advantages of this green methodology. As an application, marine sediment samples from Galicia coast (NW of Spain) were analysed. Nonylphenol and 4-tert-octylphenol were measured in all samples at concentrations between 20.1 and 1409 ng g(-1) dry weight, respectively. Sediment toxicity was estimated and no risk to aquatic biota was found.


Endocrine Disruptors/analysis , Geologic Sediments/analysis , Liquid-Liquid Extraction/methods , Tandem Mass Spectrometry/methods , Benzhydryl Compounds/analysis , Chromatography, Liquid/methods , Limit of Detection , Phenols/analysis , Pressure
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