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Dive into the research topics where I. Turnes-Carou is active.

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Featured researches published by I. Turnes-Carou.


Journal of Chromatography A | 2012

Determination of alkylphenols and bisphenol A in seawater samples by dispersive liquid–liquid microextraction and liquid chromatography tandem mass spectrometry for compliance with environmental quality standards (Directive 2008/105/EC)

N. Salgueiro-González; E. Concha-Graña; I. Turnes-Carou; S. Muniategui-Lorenzo; P. López-Mahía; D. Prada-Rodríguez

A fast, simple, sensitive and green analytical chemistry method for the simultaneous determination of alkylphenols (4-tert-octylphenol, 4-octylphenol, 4-n-nonylphenol, nonylphenol) and bisphenol A in seawater was developed and validated. The procedure was based on a dispersive liquid-liquid microextraction (DLLME) of a small volume of seawater sample (30 mL) using only 100 μL of 1-octanol, combined with liquid chromatography-electrospray ionization tandem mass spectrometry in negative mode (LC-ESI-MS/MS). The matrix effect was studied and compensated using deuterated labelled standards as surrogate standards for the quantitation of target compounds. The analytical features of the proposed method were satisfactory: repeatability and intermediate precision were <10% and recoveries were around 84-104% 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 0.005 and 0.03 μg L⁻¹, therefore the levels established in the Directive 2008/105/EC were achieved. The applicability of the proposed method was demonstrated analyzing seawater samples from different sites of A Coruña (Northwest of Spain). The analyses showed the presence of all compounds at levels between 0.035 (bisphenol A) and 0.14 μg L⁻¹ (nonylphenol).


Talanta | 2012

Blank and sample handling troubleshooting in ultratrace analysis of alkylphenols and bisphenol A by liquid chromatography tandem mass spectrometry.

N. Salgueiro-González; E. Concha-Graña; I. Turnes-Carou; S. Muniategui-Lorenzo; P. López-Mahía; D. Prada-Rodríguez

Blank contamination is a notorious problem in the ultratrace analysis of alkylphenols and bisphenol A. The achievement of low detection limits is complicated due to the high background signals. Furthermore, overestimations and underestimations in the analytical results can occur when blank levels are not stable. Thus, a review of sources of blank contamination in this type of analysis was carried out. Several sources of contamination were identified and useful guidelines are proposed for the determination of these compounds in water samples by liquid chromatography coupled with mass spectrometry. The system contamination was maintained below 0.09 ng (reagent blank) for all compounds and below 0.003 μg L(-1) (procedure blank). The main improvement was obtained by using LC-MS grade solvent in the mobile phase and PTFE syringe filters for the filtration of the sample extracts. Sample handling aspects such as filtration and storage of the water samples were also considered. The filtration of the samples should be avoided because both contamination and adsorption problems were observed when different kinds of filters were assayed. The refrigerated storage of water samples should be limited to 5 days (without addition of methanol) or 8 days (with 5% methanol).


Science of The Total Environment | 2015

Occurrence, distribution and bioaccumulation of endocrine disrupting compounds in water, sediment and biota samples from a European river basin.

N. Salgueiro-González; I. Turnes-Carou; V. Besada; S. Muniategui-Lorenzo; P. López-Mahía; D. Prada-Rodríguez

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.


Journal of Chromatography A | 2013

Membrane assisted solvent extraction coupled with liquid chromatography tandem mass spectrometry applied to the analysis of alkylphenols in water samples.

N. Salgueiro-González; I. Turnes-Carou; S. Muniategui-Lorenzo; P. López-Mahía; D. Prada-Rodríguez

This work describes the development and validation of a novel, simple, sensitive and environmental friendly analytical method for the determination of alkylphenols in different types of water samples. The methodology was based on a membrane assisted solvent extraction of only 15 mL of water sample with 500 μL of hexane in combination with liquid chromatography-electrospray ionization tandem mass spectrometry in negative mode (LC-ESI-MS/MS). Acquisition was performed in the multiple reaction monitoring (MRM) mode recording two transitions for the identification of the target compounds. Quantitation is based on the use of deuterated labelled standards as surrogate standards. The figures of merit were satisfactory in all cases: absolute recoveries were close to 50% for most investigated compounds and relative recoveries varied between 81 and 108%. Repeatability and intermediate precision were <20% 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) were lower than 0.04 μg L(-1) in all cases, which allow the achievement of the limits established by the Directive 2008/105/EC for surface and seawater samples and by the new proposal COM (2011) 876 final. The feasibility of the proposed method was demonstrated analyzing seawater, surface water and drinking water samples from different areas of A Coruña (Northwest of Spain). The analyses evidenced the presence of nonylphenol in seawater (MQL-0.13 μg L(-1)) and surface water samples (0.12-0.19 μg L(-1)). The highest concentration was observed in drinking water (0.25 μg L(-1)).


Chemosphere | 2015

Occurrence of endocrine disrupting compounds in five estuaries of the northwest coast of Spain: Ecological and human health impact

N. Salgueiro-González; I. Turnes-Carou; L. Viñas-Diéguez; S. Muniategui-Lorenzo; P. López-Mahía; D. Prada-Rodríguez

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.


Journal of Chromatography A | 2015

Pressurized hot water extraction followed by miniaturized membrane assisted solvent extraction for the green analysis of alkylphenols in sediments

N. Salgueiro-González; I. Turnes-Carou; S. Muniategui-Lorenzo; P. López-Mahía; D. Prada-Rodríguez

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.


Analytica Chimica Acta | 2014

Analysis of endocrine disruptor compounds in marine sediments by in cell clean up-pressurized liquid extraction-liquid chromatography tandem mass spectrometry determination

N. Salgueiro-González; I. Turnes-Carou; S. Muniategui-Lorenzo; P. López-Mahía; D. Prada-Rodríguez

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.


Marine Pollution Bulletin | 2016

Occurrence of alkylphenols and bisphenol A in wild mussel samples from the Spanish Atlantic coast and Bay of Biscay

N. Salgueiro-González; I. Turnes-Carou; Lucía Viñas; V. Besada; S. Muniategui-Lorenzo; P. López-Mahía; D. Prada-Rodríguez

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.


Chromatographia | 2002

Simultaneous separation of amidoamines and benzalkonium chloride surfactants by capillary zone electrophoresis

I. Turnes-Carou; C. Prieto-Blanco; P. López-Mahía; S. Muniategui-Lorenzo; D. Prada-Rodríguez

SummaryA protocol is described for the spearation of quaternary amidoamines as well as benzalkonium chloride compounds formulated with the same hydrophobic chain. A baseline separation of the twelve homologues studied was achieved in less than 3.5 minutes using a 56 cm of effective capillary length. The carrier electrolyte was 75 mM phosphate, pH=5.2, with acetonitrile (40%v/v) as organic modifier. The applied voltage was 30 kV and the capillary temperature was thermostated to 40°C. Samples were injected hydrodynamically by applying a positive pressure of 50 mbar for 20 s. Organic modifier was also required in the sample solution to disrupt the formation of micelles by the long-chain surfactants. For this reason, the sample and standards were diluted with acetonitrile: water solution (40%v/v) to appropriate concentrations.


Water Air and Soil Pollution | 2015

The Influence of Oceanic Air Masses on Concentration of Major Ions and Trace Metals in PM2.5 Fraction at a Coastal European Suburban Site

Jorge Moreda-Piñeiro; I. Turnes-Carou; Elia Alonso-Rodríguez; Carmen Moscoso-Pérez; Gustavo Blanco-Heras; P. López-Mahía; S. Muniategui-Lorenzo; D. Prada-Rodríguez

A comprehensive chemical characterisation of the ionic and metallic composition of PM2.5 fraction of suburban aerosol collected with high‐volume aerosol samplers at a coastal suburban site of northwest Atlantic European is studied over a 1.5-year period (from March 2011 to August 2012). The monthly mean PM2.5 mass concentrations (after gravimetric measurement) ranged from 13 to 26xa0μgxa0m−3. Eighteen samples, which provide information pertaining to the monthly variation in chemistry, were analyzed. Trace metals (Al, As, Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V and Zn) were analysed in PM2.5 fraction after acid extraction (total metallic concentration) and after sonication-assisted water extraction (aqueous soluble fraction). Major inorganic ions (Cl−, NO3−, SO42−, Na+, K+, Ca2+, Mg2+, NH4+ and C2O42−) were also analysed in the aqueous fraction of PM2.5. Trace metal extractability in water was in the range 50–67xa0% with exception of Al (∼2xa0%), Fe (∼4xa0%) and Cr (∼18xa0%). After univariate, cluster (CA) and principal component (PCA) analyses and air mass backward trajectory analysis, marine, crustal and anthropogenic (including road traffic) sources were found for the inorganic composition of PM2.5. Results also suggest a great influence of cleaner Atlantic air masses and ubiquitous sources for K+, Mg2+, Fe, Ni and V.

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