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During stoppers production, large amounts of cork by-products (CBPs) are generated, being used as low-value material. This project aims to turn CBPs into smart, natural and sustainable materials (sorbent) for solid-phase extraction (SPE) of pesticides from water. The study describes the use of CBPs for the extraction of 17 fungicides (metalaxyl, cyprodinil, tolylfluanid, procymidone, folpet, fludioxonil, myclobutanil, kresoxim methyl, iprovalicarb, benalaxyl, trifloxystrobin, fenhexamid, tebuconazole, iprodione, pyraclostrobin, azoxystrobin and dimethomorph) followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis. The most critical parameters affecting SPE were optimized by experimental design methodology. Under the optimal conditions, the method was successfully validated in terms of linearity, repeatability, and intermediate precision. Fungicide recovery was assessed in different real water samples including river, fountain, rainwater and spring water at 3 concentration levels (0.1, 0.5 and 10 µg L -1 ). Recoveries ranged between 70-118% with RSD values lower than 20%, and matrix effects were not observed. Finally, the method was applied to samples from irrigation, rain, and river water, all collected in vineyards areas, revealing the presence of 10 of the 17 fungicides, at concentration up to hundreds of µg L -1 . The use of CBPs seems to be a promising low-cost and ecofriendly alternative to be employed as sorbent in SPE techniques to extract fungicides from the aquatic environment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A rapid environmental pollution screening and monitoring workflow based on fabric phase sorptive extraction-gas chromatography-tandem mass spectrometry (FPSE-GC-MS/MS) is proposed for the first time for the analysis of 17 widespread used fungicides (metalaxyl, cyprodinil, tolylfluanid, procymidone, folpet, fludioxonil, myclobutanil, kresoxim methyl, iprovalicarb, benalaxyl, trifloxystrobin, fenhexamid, tebuconazole, iprodione, pyraclostrobin, azoxystrobin and dimethomorph) in environmental waters. The most critical parameters affecting FPSE, such as sample volume, matrix pH, desorption solvent and time, and ionic strength were optimized by statistical design of experiment to obtain the highest extraction efficiency. Under the optimized conditions, the proposed FPSE-GC-MS/MS method was validated in terms of linearity, repeatability, reproducibility, accuracy and precision. To assess matrix effects, recovery studies were performed employing different water matrices including ultrapure, fountain, river, spring, and tap water at 4 different concentration levels (0.1, 0.5, 1 and 5 µg/L). Recoveries were quantitative with values ranging between 70-115%, and relative standard deviation values lower than 14%. Limits of quantification were at the low ng/L for all the target fungicides. Finally, the validated FPSE-GC-MS/MS method was applied to real water samples, revealing the presence of 11 out of the 17 target fungicides., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The photodegradation behaviour for nine widespread fungicides (benalaxyl, cyprodinil, dimethomorph, fenhexamide, iprovalicarb, kresoxim-methyl, metalaxyl, myclobutanil and tebuconazole) was evaluated in different types of water. Two different systems, direct UV photolysis and UVC/H 2 O 2 advanced oxidation process (AOP), were applied for the photodegradation tests. For the monitoring of the target compound degradation, a method based on direct injection liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. Several fungicide photodegradation by-products were tentatively identified by high-resolution mass spectrometry (HRMS) as well. For the photolysis studies, the efficiency of different types of radiation, UVC (λ = 254 nm) and UVA (λ = 365 nm), was compared. UVC photolysis provided the highest removal with a complete degradation for fenhexamide and kresoxim-methyl, and percentages between 48 and 78% for the other compounds, excluding iprovalicarb and myclobutanil with removals <35%, after 30 min of irradiation. Besides, the photodegradation tests were performed with different initial concentrations of fungicides, and the efficiency of two photoreactor systems was compared. In all cases, the kinetics followed pseudo-first order, and the half-life times could also be calculated. The addition of H 2 O 2 under UVC light allowed an improvement of the reaction kinetics, especially for the most recalcitrant fungicides, obtaining in all cases removals higher than 82% in less than 6 min. Finally, in order to evaluate the suitability of the proposed systems, both UVC photolysis and UVC/H 2 O 2 system were tested in different real water matrices (wastewater, tap water, swimming pool water and river water), showing that the UVC/H 2 O 2 system had the highest removal efficiency in less than 6 min, for all water samples.

Ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) followed by gas chromatography-triple quadrupole-mass spectrometry (GC TQ-MS) were used for the rapid determination of 11 fungicides (metalaxyl, cyprodinil, procymidone, iprovalicarb, myclobutanyl, kresoxim-methyl, benalaxyl, fenhexamide, tebuconazole, iprodione and dimethomorph) in white grape bagasse. The extractions were optimized on real non-spiked samples by means of experimental design and the optimal conditions were selected to achieve the method validation. The PLE procedure showed much higher efficiency than UAE for the target fungicides. Under the selected extraction conditions, PLE showed satisfactory linearity, repeatability and reproducibility. Recoveries for the majority of studied fungicides were higher than 80% with relative standard deviations (RSD) lower than 12%. Limits of detection (LODs) for GC TQ-MS were very low, at the sub ngg(-1) for the majority of the target fungicides, well below the European maximum residue limits (MRLs) for wine and table grapes, and vine leaves. Eighteen white grape bagasse samples were analyzed and nine out of eleven targets were detected in the samples. Seven of them were detected in more than 50% of the samples and most samples contained at least four of the target analytes. The most frequently found compounds were tebuconazole and dimethomorph with concentrations between 1.6-130 and 2.0-1788ngg(-1), respectively. Some samples showed high levels of many of the studied fungicides (high ngg(-1), even μgg(-1) for cyprodinil, fenhexamide, iprodione and dimethomorph), but all of them below the European maximum residue limits (MRLs) for wine grapes., (Copyright © 2014 Elsevier B.V. All rights reserved.)