Publications by authors named "Maria Ramil"

Agricultural management influences the soil ecosystem by affecting its physicochemical properties, residues of pesticides and microbiome. As vineyards grow crops with the highest incidence of pesticides, the aim of this study was to evaluate the impact of conventional and sustainable management systems of vineyards from DOP Ribeiro on the soil's condition. Samples from soils under three different management systems were collected, and the main soil physicochemical properties were evaluated.

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In this work, a procedure for the sensitive and selective determination of chlorhexidine in sludge from municipal sewage treatment plants (STPs) based on matrix solid-phase dispersion (MSPD) and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was optimized and validated. Analysis of sewage sludge samples, obtained from different STPs in Northwest Spain from 2018 to 2021, showed that chlorhexidine was ubiquitous in this environmental compartment with concentrations between 0.3 and 16 µg g.

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Evidence of pesticide transfer from grapes to wine, added to differences in the national regulations regarding the number and the maximum concentration of these species in wine, demands analytical procedures suitable for their routine control in this foodstuff. In this research, solid-phase extraction (SPE) and ultra-performance liquid chromatography (UPLC), with tandem mass spectrometry (MS/MS) detection, are combined to obtain a sensitive and rapid procedure to determine 50 pesticides in red and white wines. Efficiency and selectivity of sample preparation are correlated with the type of sorbent, the elution solvent, and the physicochemical properties of pesticides.

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Quinoxyfen has been recently identified as a priority hazardous substance in the field of the European water policy. In this work, its fate in aqueous samples and solid supports under UV and solar radiation is investigated. Diverse degradation experiments were carried out, at lab scale, using spiked aliquots of different aqueous matrices (ultrapure, treated wastewater and river water) irradiated at different wavelengths (λ = 254 nm, λ = 365 nm and solar light).

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The effects of nitrate in the kinetics and the transformation routes of the fungicide cyprodinil (CYP) were investigated using aqueous solutions, ultrapure water and river water samples, spiked with the precursor compound and containing different levels of nitrate. Samples were exposed either to 254 nm radiation or to solar light, depending on the experiment. Time course of CYP and formation of transformation products (TPs) were simultaneously assessed by direct injection of different irradiation time aliquots in a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) system.

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The efficiency of UV irradiation for the removal of the antimycotic drugs fluconazole (FCZ) and climbazole (CBZ) from water samples is evaluated. Degradation experiments, at laboratory scale, were carried out with spiked aliquots of ultrapure water solutions and treated wastewater samples using low-pressure mercury lamps emitting at 254 nm. Time course of precursor pollutants and identification of arising transformation products (TPs) was performed by injection of different reaction time aliquots in a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) system.

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Time-of-flight accurate mass spectrometry (TOF-MS), following a previous chromatographic (gas or liquid chromatography) separation step, is applied to the identification and structural elucidation of quinoline-like alkaloids in honey. Both electron ionization (EI) MS and positive electrospray (ESI+) MS spectra afforded the molecular ions (M(.+) and M+H(+), respectively) of target compounds with mass errors below 5 mDa.

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The reactivity of three imidazolic, environmental persistent antimycotic drugs (clotrimazole, CTZ; ketoconazole, KTZ; and miconazole, MCZ) upon exposure to ultraviolet (UV) radiation is discussed. First, precursor compounds were immobilized in a silicone support which was further exposed to UV light at two different wavelengths: 254 and 365 nm. After solvent desorption, degradation kinetics of the precursor pharmaceuticals, identification of the arising transformation products (TPs) and evaluation of their time-course were investigated by liquid chromatography (LC) with quadrupole time-of-flight (QTOF) mass spectrometry (MS) detection.

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An effective and selective, modular sample preparation method for the extraction of eight antimycotic drugs, belonging to three different chemical classes, from digested sludge samples is proposed. To this end, matrix solid-phase dispersion (MSPD) was on-line connected with a cationic exchanger solid-phase extraction (SPE) cartridge. Analytes were extracted from the MSPD syringe, which contained the freeze-dried sludge sample dispersed with C18 plus a clean-up layer of primary and secondary amine (PSA) sorbent, with 10 mL of methanol.

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A simplified sample preparation method, based on the matrix solid-phase dispersion technique, is proposed for the sensitive determination of 15 organic fungicides in vineyard soils by gas chromatography-mass spectrometry (GC-MS). Under final working conditions, sieved samples (0.5 g) were blended and dispersed with 2 g of C18 and transferred to a polypropylene syringe containing 1 g of diatomaceous earth.

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Stir-bar sorptive extraction and liquid desorption followed by large volume injection-gas chromatography coupled to mass spectrometry under selected ion monitoring mode acquisition (SBSE-LD/LVI-GC-MS(SIM)) was applied for the determination of six benzotriazole UV stabilizers (Tinuvin P, Allyl-bzt, Tinuvin 320, Tinuvin 326, Tinuvin 327 and Tinuvin 328) in wastewater matrices. Parameters affecting the performance of extraction and desorption steps were thoroughly evaluated using uni- and multivariate optimization strategies, based on the use of experimental factorial designs. Assays performed with stir bars, coated with 24 μL of polydimethylsiloxane, on 25 mL of ultra-pure water samples spiked at the 0.

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The serotonin re-uptake inhibitor fluoxetine was selected for an environmental risk assessment, using the most recent European guideline (EMEA 2006) within the European Union (EU)-funded Environmental Risk Assessment of Pharmaceuticals (ERAPharm) project due to its environmental persistence, acute toxicity to nontarget organisms, and unique pharmacokinetics associated with a readily ionizable compound. As a widely prescribed psychotropic drug, fluoxetine is frequently detected in surface waters adjacent to urban areas because municipal wastewater effluents are the primary route of entry to aquatic environments. In Phase I of the assessment, the initial predicted environmental concentration of fluoxetine in surface water (initial PEC(SW)) reached or exceeded the action limit of 10 ng/L, when using both a default market penetration factor and prescription data for Sweden, Germany, and the United Kingdom.

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A sensitive procedure for the determination of five ultraviolet (UV) absorbers, belonging to the benzotriazole class, in environmental water samples is proposed. Analytes were first extracted and concentrated from the matrix and then selectively determined by gas chromatography in combination with tandem mass spectrometry detection. The high lipophilic character of some of the investigated species resulted in a strong trend to remain sorbed on solid surfaces, even after addition of considerable percentages of methanol (up to 30%) to water.

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The fate of beta blockers (atenolol, acebutolol, bisoprolol, celiprolol, metoprolol, nadolol, pindolol, propranolol, and sotalol) was studied in surface water-sediment systems. A new analytical method was developed to determine the beta blockers in sediments by LC-ESI-tandem MS detection. The relative recoveries in sediments ranged from 89 +/- 7% (acebutolol) to 102 +/- 3% (nadolol) using deuterated surrogate standards.

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In this study, different approaches were used to assess and overcome the severe effects of interference from the sample matrix from different types of sludges and wastewater on the analysis of nine beta-blockers and the beta sympathomimetic clenbuterol. The partitioning of the target compounds into sludge was investigated in wastewater treatment plants (WWTPs) in both Canada and Germany to evaluate whether this is an important mechanism for removal from sewage. Due to ion suppression in the electro spray interface, absolute recoveries were for certain compounds even lower than 20%.

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An analytical method was developed to analyze eight psychoactive pharmaceuticals--including the antiepileptic carbamazepine, the opiates morphine, codeine, dihydrocodeine, the opiode tramadol, and the tranquilizers diazepam, oxazepam, temazepam--and the antibiotic sulfamethoxazole as well as three metabolites (10,11-dihydrocarbamazepine (DHC), 10,11-dihydroxy-10, 11-dihydrocarbamazepine, and N4-acetylsulfamethoxazole) in river sediments. Relative recoveries of all analytes exceeded 97% using either deuterated or 13C15N-labeled surrogate standards. Sorption isotherms of all analytes were constructed at pH 6.

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Atenolol is a beta-adrenergic receptor antagonist ('beta-blocker') widely used for the treatment of angina, glaucoma, high blood pressure and other related conditions. Since atenolol is not appreciably metabolized in humans, the parent compound is the predominant excretory product, and has been detected in sewage effluent discharges and surface waters. Consequently, atenolol has been chosen as a reference pharmaceutical for a European Union-funded research consortium, known as ERAPharm (http://www.

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Although widely used for the treatment of endo- and ectoparasites in livestock and pets, very few data on chronic effects on aquatic organisms are available for the parasiticide ivermectin. In the present study, toxicity of ivermectin to two freshwater organisms, the cladoceran Daphnia magna and the green alga Pseudokirchneriella subcapitata was investigated. For D.

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