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The effects of four fungicides commonly used for the control of fungal diseases in vines and grapes in the course of winemaking were tested. The concentration of fungicide residues was monitored throughout the process to establish their kinetics of dissipation. In all cases the percentages of dissipation were >68%, which shows the detoxificant effect of the winemaking process. On the other hand, the effect of the fungicide residues on the aroma composition of Tempranillo red wines was tested. To evaluate possible modifications on the aroma profile of wines, seven odorant series (ripe fruits, fresh fruits, lactic, floral, spicy, vinous, and herbaceous) were built from the odor activity values (OAVs) obtained for each volatile compound. Ripe fruits and fresh fruits were the major aromatic attributes in all Tempranillo red wines. These two odorant series registered the highest variations in their total OAVs with respect to the control wine, especially with the application of boscalid + kresoxim-methyl into vines, leading to a decrease in the ripe fruit and fresh fruit nuances of the resulting wines. Moreover, when the effect of these fungicides on the aroma of Tempranillo red wines was compared throughout two years (2012 and 2013), wines elaborated from grapes treated in the field with boscalid + kresoxim-methyl in 2013 displayed the highest variation in aroma profile with respect to control wine.

Grapefruit is a rich source of flavonoids but also contains furanocoumarins, which are known to strongly interact with a variety of medications. Thus, characterization of grapefruit furanocoumarin metabolites may help in a better understanding of grapefruit-drug interactions. In the present work, identification of the main metabolites of grapefruit juice furanocoumarins in urine was performed by ultraperformance liquid chromatography (UPLC) coupled to linear ion trap-Orbitrap mass spectrometry (LTQ-Orbitrap). Glucuronides of 6',7'-dihydroxybergamottin and a hydroxybergamottin-like metabolite were identified for the first time as grapefruit juice metabolites. Afterward, a fast and sensitive method based on solid-phase extraction (SPE) and UPLC coupled to triple quadrupole-tandem mass spectrometry (QqQ-MS/MS) was developed for determination of the identified metabolites in urine. The proposed method was applied to urine samples of five volunteers after intakes of moderate doses of grapefruit, lemon, and orange juices. Furanocoumarin metabolites were only detected in urines after consumption of grapefruit juice.

The analysis of food components and their metabolome in urine has recently found a growing interest due their potential ability to reflect specific dietary intakes. In the present work, a fast, simple, and environmentally friendly method based on liquid chromatography coupled to electrospray ionization tandem mass spectrometry was developed for the analysis of main wine organic acids in human urine. The proposed method was evaluated in terms of linearity, precision, accuracy, and limits of detection. Quantitative recovery (96-102%) and satisfactory interday precision (RSD <6%) were achieved for all target compounds. To demonstrate the applicability of the method, urine samples from five male volunteers were analyzed before and after consumption of a single moderate dose (200 mL) of red wine. A significant increase (p < 0.01) in the urinary concentration of tartaric and malic acids was observed.

Olives from Picual, Arbequina, Manzanilla de Sevilla, and Local cultivars together with their corresponding oils were analyzed in terms of odor activity values (OAVs) to establish the relationship between the aromatic profile of both olives and oils. The OAVs for the different compounds were classified in nine odorant series: grass, leaf, wood, bitter, sweet, pungent, olive fruit, apple, and banana. The total intensities for every aromatic series were calculated as the sum of the OAVs of each compound associated with this series. As a result, olives had characteristic profiles. Picual cultivar had not a clear sensory characterization from the volatile compounds. Arbequina cultivar was mainly characterized by apple and bitter odorant series; Manzanilla de Sevilla by apple, bitter, and grass odorant series; and Local variety by banana and olive fruit. However, in the oils obtained from those olives, these differences disappeared, and all oils showed the same profile with pungent, bitter, and wood odorant series most strongly contributing.

Quaternary Ammonium Herbicides (QUATs) are nonselective contact herbicides, widely used at weed emergence to protect a wide range of crops. The benefits achieved by the use of these herbicides are indisputable. In soils devoted to vineyards, their uses increase the yield and the quality of the grapes for winemaking. However, several environmental dangers have emerged from the overuse of these compounds. Therefore, there has been a great interest in the presence of these compounds in soils, water, and food. Once in the soil, the mobility of these agrochemicals plays an important role in their fate and transport in the environment. This is why we mainly focused our review on (a) their physical and chemical properties and their activity, (b) the factors affecting their mobility in soils, (c) the quality of surrounding waters, and (d) the measures to reduce their contamination, especially in the case of agricultural soils devoted to vineyards.

The relationship between the proanthocyanidin profile and the perceived astringency was assessed in 13 commercial Tempranillo red wines. The concentration and compositional information were obtained by liquid chromatography with diode array detection coupled to electrospray ionization mass spectrometry after acid-catalyzed depolymerization of wine proanthocyanidins in the presence of excess phloroglucinol. Statistical analysis of the results showed significant correlations between sensory and chemical determinations. Astringency was more affected by the subunit composition than by the total concentration or the average degree of polymerization of wine proanthocyanidins. Higher proportions of epicatechin (EC) subunits in extension positions and gallocatechin (GC) subunits in terminal positions were shown to increase astringency. On the contrary, the amount of epigallocatechin (EGC) in both extension and terminal positions was negatively correlated with the perceived astringency.

When used to fine wines, bentonite acquires a protein load that makes it a potentially useful fertilizer. Other properties of bentonite are also potentially useful for soil amendment. In the work described in this paper, waste bentonite from a winery was applied to an acid soil, and its effects on soil properties and on the growth of Lolium multiflorum were evaluated. Soil N, K, and P contents all increased, as did pH and cation exchange capacity. Biomass production increased as the dose of bentonite increased up to 5 g kg(-1), decreasing at larger doses (possibly as a result of falling potassium/magnesium ratio and increasing electrical conductivity). Environmental drawbacks of waste bentonite include its high soluble copper content, although its conversion in the soil to less soluble forms reduces its potential phytotoxicity. The copper, manganese, and zinc contents of the ryegrass crop were low.

The upper horizons of old vineyard soils have substantial copper contents due to the traditional use of copper-based fungicides. Total copper levels in eight vineyard soils in the Rías Baixas area of Galicia (northwestern Spain) ranged from 60 to 560 mg kg(-1) (mean +/- SD = 206 +/- 170 mg kg(-1)). The adsorption of the fungicides metalaxyl (pK(a) = 1.41) and penconazole (pK(a) = 2.83) by these soils was determined using fungicide solutions of pH 2.5 and 5.5, and desorption of fungicide adsorbed at pH 5.5 was also determined. In all cases, Freundlich equations were fitted to the data with R (2) > 0.96. Penconazole was adsorbed and retained more strongly than metalaxyl, with K(F) values more than an order of magnitude greater. In the desorption experiments, both fungicides exhibited hysteresis. Soil copper content hardly affected the adsorption of metalaxyl, but K(F) values for adsorption of penconazole increased at a rate of about 0.1 mL(n) (microg of penconazole)(1-n) (microg of Cu)(-1), which is attributed to the formation of Cu(2+)-penconazole complexes with greater affinity for soil colloids than penconazole itself. Because the dependence of K(F) for penconazole adsorption on copper content was the same at both pH values, complex formation appears not to have been affected by the solubilization of 6-17% of soil copper at pH 2.5. A similar copper dependence, or lack of dependence, was observed when 100-1000 mg kg(-1) of copper was added as Cu(NO(3))(2).2H(2)O to the solutions from which the fungicides were adsorbed.

The influence of methanol on the adsorption of the fungicide cyprodinil by a crop soil was studied by equilibrium measurements and by determining the retention-release dynamics in a continuous stirred flow tank reactor (CSTR). Equilibrium measurements showed the effective coefficient of partition of cyprodinil between soil and solution, K(dc), decreases linearly as the concentration of methanol in the solution increases until a percentage of 20% is reached. In CSTR experiments, the retention of cyprodinil was found to be almost reversible; up to a 95% of the fungicide was desorbed. The retention-release dynamics showed biphasic behavior and was partially controlled by diffusion. This behavior was reproduced by a model of diffusion into micropores identifying the soil particles as spheres and taking into account both intraparticle nonlinear adsorption and nonlinear adsorption at external surfaces. In all cases, the sorption kinetics was not the limiting step. The main effect of methanol in the retention-release dynamics ended up being based on the changes produced in the adsorption equilibrium. Methanol also increased the effective diffusion coefficient and decreased the mass transfer coefficient. The optimized Freundlich's isotherm coefficients for <5% methanol were lower than those obtained from the batch experiments.

The effect of micellar aggregates upon the stability of carbofuran in basic media has been studied. The effect of the presence of micelles upon the basic hydrolysis of carbofuran is a function of the nature of the surfactant monomer. Important catalysis of basic hydrolysis of carbofuran in the presence of colloid aggregates with positive surface charge has been reported. On the other hand, the presence of anionic and nonionic surfactants implies a large inhibition of the basic hydrolysis of carbofuran. Both catalysis and inhibition are due to the association of carbofuran with the micellar core. The kinetic constants for the basic hydrolysis of carbofuran in these microheterogeneous media have been obtained on the basis of a micellar pseudophase model. No significant changes in the intrinsic reactivity of HO- against carbofuran have been observed.

Endosulfan is a potentially harmful, degradation resistant pesticide that is found in soils where it has been used. Despite being hydrophobic and having high affinity for soil matrix components, it has also been found in groundwater. To investigate this behavior, we studied the passage of a commercial emulsified formulation through a column of aggregated vineyard soil under simulated light rain. Breakthrough data were obtained using gas chromatography with electron capture detection to determine the concentration of endosulfan in samples extracted from the column periodically at several depths. These data, and analogous data obtained previously for the passage of bromide, were analyzed using the program CXTFIT v.2. Analysis of the bromide data strongly suggested the existence of preferential flow paths in the column. The endosulfan data were adequately accounted for by a model in which the preferential flow and nonpreferential flow regions are almost isolated from each other. These regions differ also as regards both the partition of endosulfan between soil and soil solution and the rate at which reversibly adsorbed endosulfan is transformed into irreversibly adsorbed endosulfan. The "irreversibility" sink term accounts also for biological and chemical degradation of endosulfan. The findings imply that soil humidity favors the transport of commercial endosulfan by the formation and maintenance of preferential flow paths in soil, controlling both the presence of endosulfan in groundwater and its high persistence in soil.

Cyprodinil and fludioxonil are new-generation fungicides that are employed to protect grapevines from botrytis and various rots. In this work, their adsorption and desorption dynamics in eight vineyard soils from Galicia (northwestern Spain) were examined in batch and column experiments. Both fungicides exhibited linear adsorption isotherms, with more ready adsorption (greater Kd) of fludioxonil. Kd values for cyprodinil were significantly correlated with soil organic matter content (r 2= 0.675, p < 0.01). Both pesticides exhibited adsorption-desorption hysteresis, but desorption was easier and more variable for cyprodinil (12-21%, RSD = 17%) than for fludioxonil (3-5%, RSD = 13%) and appeared to depend on the formation of irreversible bonds in the former case and on poor solubility in the latter. A linear adsorption model involving nonequilibrium conditions and an irreversible adsorption term was found to reproduce transport behavior accurately.

Residual levels and degradation rates of tebuconazole and dichlofluanid in lettuce plants grown in a greenhouse under agricultural conditions typical of northwestern Spain were studied. Lettuce plants were sprayed four times with a homogeneous 0.2% aqueous solution of Folicur Combi (wettable powder containing 40% dichlofluanid and 10% tebuconazole) at a rate of 2500 g/ha. Samples were collected 1, 5, and 9 days after the first two applications and at times ranging from 1 to 27 days after the last two applications. All samples were stored in a refrigerator at 4 degrees C. Fungicide levels were determined by solid-liquid extraction (SLE) followed by gas chromatography and mass spectrometry detection (GC-MSD). Recovery was good for tebuconazole (98%) but low for dichlofluanid (29%); precision was good (<10% for both analytes), and quantification limits were low (<1.5 mg/kg). Seven days after the last application, dichlofluanid levels were below the maximum allowed limit established in Spain (10 mg/kg), but tebuconazole levels were above the corresponding limit (5 mg/kg). Tebuconazole concentration dynamics was accurately fitted by zeroth- or combined first- and zeroth-order models (depending on variety), but modeling of the behavior of dichlofluanid was less satisfactory, probably due to its instability.

This paper describes a sensitive method for the simultaneous quantification of eight commonly used grapevine fungicides in vineyard soils: cyprodinil, fludioxonil, metalaxyl, penconazole, pyrimethanil, procymidone, tebuconazole, and vinclozolin. The fungicides are extracted from the soil sample by sonication with water followed by shaking with ethyl acetate and are quantified by gas chromatography with mass spectrometry. Average extraction efficiencies in a sample of seven spiked, previously fungicide-free soils were > or =79% for all of the analytes, method precisions were > or =17%, and quantification limits were < or =50 microg/kg. However, because recoveries varied considerably from soil to soil, there is a need to control for soil matrix differences (mainly soil pH and exchangeable calcium content); as a consequence, soil fungicide contents must be quantified by the standard additions method. When the method was applied in this way to soil samples from vineyards belonging to the specified wine-growing region of Rias Baixas (Galicia, northwestern Spain) taken at the beginning of October (1 month after the crop's final treatment), levels of fludioxonil as high as 991 microg/kg were found, but at the start of the season (9 months after the previous crop's final treatment) only fludioxonil was detected at levels higher than its limit of quantification (45 and 52 microg/kg).

Simple, rapid, and inexpensive methods have been developed for the determination of polycyclic aromatic hydrocarbons (PAHs) in drinking waters without interferences from other chemical contaminants by use of two different extraction techniques and analysis by an optimized reverse-phase (RP) high-performance liquid chromatography followed by fluorescence detection (HPLC-FLD) method. The feasibility of SPE (solid-phase extraction) and SPME (solid-phase microextraction) for the determination of PAH in drinking water samples has been evaluated. Several parameters have been studied and optimized for both extraction procedures. The relationship between the nature of the fibers and the quantity of extracted compounds and the effects of organic solvent, salt addition, sampling temperature, and sampling time was studied for SPME. Acetonitrile percentage added to the sample, sample storage conditions (temperature and time), and type of organic elution solvent and elution volume were evaluated for SPE. The results show that both extraction procedures can be used to determine PAHs in drinking waters, but SPE gives better performance (recovery, precision, and quantification limits) for the determination of PAHs in drinking water at the levels established by the legislation.

Before wood ash can be safely used as a fertilizer in soils, possible negative effects such as input of organic contaminants or remobilization of contaminants already stored in the soil must be investigated. The objective of this study was to optimize and characterize extraction methods to isolate and quantitatively measure polycyclic aromatic hydrocarbons (PAHs) concentrations in wood ash that can be used as amendment of soils. It will be then possible to examine the effects of wood ash application on PAHs concentrations in the washing waters with the aim of evaluating their distribution by storage in the different compartments and what influences their stability and persistence. Simple, rapid and inexpensive methods have been set up for the determination of seven polycyclic aromatic hydrocarbons (PAHs) in wood ashes and ash aqueous extracts without interferences from other chemical contaminants using organic solvent extraction and/or SPE techniques and analyzed by an optimized RP-HPLC-FLD method. The feasibility of extraction for the determination of PAHs in wood ashes has been evaluated because PAHs are strongly sorbed to such a matrix, which explains why the PAHs content in ash was seldom studied. The method resulted to be of recoveries ranging from 81 to 97% for the different PAHs, with repeatabilities (RSDs%) better than 6%. Detection levels were from 0.2 to 2.2 microg/kg, while quantification limits were from 0.7 to 5.6 microg/kg, low enough to evaluate the presence of PAHs in wood ashes.

Soil inputs produced by rainfall waters washed off through a Ribeiro vineyard (Galicia, northwestern Spain) confirmed that levels recovered are <5% of the added fungicides. Laboratory studies showed that some fungicides were degraded in the ODS cartridge used for the collection of fungicides washed off by rainfall. Procymidone wash-off data obtained in the vineyard can be explained by a first-order rate mass transfer model. A procedure for the collection of wash-off waters based on octadecylsilane solid phase extraction, followed by an analytical method of reverse-phase liquid chromatography with diode array detection is presented for the evaluation of fungicide inputs into soils after being washed off vineyards by rainfalls. Quality parameters of the analytical method yielded good precision (RSD < 10%) and low detection limits (ranging between 1 and 21 microg/L).

Sulfamethazine (SMZ) and trimethoprim (TMP) are antibacterials used in veterinary practice. This paper describes a method for their determination in veterinary liquid feed premixes that is based on liquid chromatography with diode array detection. Gradient elution with methanol and ammonium acetate achieved excellent separation of the two analytes within 15 min without any interference from the matrix. Absorbance of the column effluent was monitored at 264 nm for SMZ and at 230 nm for TMP. Detailed analyses of the uncertainties of determinations afford estimated expanded uncertainties of, respectively, 0.2 and 0.1 w/v % for typical SMZ and TMP concentrations of 10.7 and 2.1 w/v %, respectively. At the lower end of the calibrated range of the method, the dominant source of uncertainty is the preparation of standards and the construction of the calibration line.

To establish the stability of Ultranox 626 (an antioxidant added to plastics) in food simulants under migration conditions, migrations tests have been performed. A method has been developed for the determination of Ultranox 626 in the aqueous food simulants distilled water, 3% (w/v) acetic acid, and 15% (v/v) ethanol and in the fatty food simulants 95% (v/v) ethanol and isooctane. The method uses reversed-phase high-performance liquid chromatography with ultraviolet detection at 230 nm, is fast, and can be run automatically. To determine the stability of Ultranox 626, it was heated in each of the listed food simulants under the conditions stipulated in EU regulations for testing for compliance with migration limits. These experiments showed that this additive had acceptable stability in water, 15% and 95% (v/v) ethanol, and isooctane but that it decomposed completely in 3% (w/v) acetic acid. Migration testing with 3% acetic acid is of no use, since by the end of the testing regime the additive will have undergone substantial or total decomposition, and the level detected will not reflect the true level of migration. The EU Commission should replace 3% acetic acid with 15% ethanol as an appropriate test simulant for the determination of Ultranox 626 in all types of acid- and alcohol-containing foodstuffs. A number of experiments were carried out to develop a suitable method for the determination of Ultranox in fat simulants such as olive oil and HB 307. It appeared not possible, within the scope of this project, to obtain a method suitable to establish the stability of Ultranox 626 in fat simulants. Best results were obtained by freezing out the fat at -80 degrees C, but recovery was limited to 50%, which was insufficient for the intended purpose. Further experiments are required to establish the stability of Ultranox 626 in fat simulants such as olive oil and HB 307.