68 research outputs found

    Determination of pesticides in fruit and fruit juices by chromatographic methods. An overview

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    In order to combat a variety of pests, pesticides are widely used in fruits. Several extraction procedures (liquid extraction, single drop microextraction, microwave-assisted extraction, pressurized liquid extraction, supercritical fluid extraction, solid-phase extraction, solid-phase microextraction, matrix solid-phase dispersion, and stir bar sorptive extraction) have been reported to determine pesticide residues in fruits and fruit juices. The significant change in recent years is the introduction of the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) methods in these matrices analysis. A combination of techniques reported the use of new extraction methods and chromatography to provide better quantitative recoveries at low levels. The use of mass spectrometric detectors in combination with liquid and gas chromatography has played a vital role to solve many problems related to food safety. The main attention in this review is on the achievements that have been possible because of the progress in extraction methods and the latest advances and novelties in mass spectrometry, and how these progresses have influenced the best control of food, allowing for an increase in the food safety and quality standards

    Dual augmentation for aerobic bioremediation of MTBE and TCE pollution in heavy metal-contaminated soil

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    In this work we isolated from soil and characterized several bacterial strains capable of either resisting high concentrations of heavy metals (Cd2+ or Hg2+ or Pb2+) or degrading the common soil and groundwater pollutants MTBE (methyl-tertbutyl ether) or TCE (trichloroethylene). We then used soil microcosms exposed to MTBE (50 mg/l) or TCE (50 mg/l) in the presence of one heavy metal (Cd 10 ppm or Hg 5 ppm or Pb 50 or 100 ppm) and two bacterial isolates at a time, a degrader plus a metalresistant strain. Some of these two-membered consortia showed degradation efficiencies well higher (49–182% higher) than those expected under the conditions employed, demonstrating the occurrence of a synergetic relationship between the strains used. Our results show the efficacy of the dual augmentation strategy for MTBE and TCE bioremediation in the presence of heavy metals

    Mass spectrometry parameters optimization for the 46 multiclass pesticides determination in strawberries with gas chromatography ion-trap tandem mass spectrometry

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    Multiclass analysis method was optimized in order to analyze pesticides traces by gas chromatography with ion-trap and tandem mass spectrometry (GC-MS/MS). The influence of some analytical parameters on pesticide signal response was explored. Five ion trap mass spectrometry (IT-MS) operating parameters, including isolation time (IT), excitation voltage (EV), excitation time (ET),maximum excitation energy or “q” value (q), and isolationmass window (IMW) were numerically tested in order to maximize the instrument analytical signal response. For this, multiple linear regression was used in data analysis to evaluate the influence of the five parameters on the analytical response in the ion trap mass spectrometer and to predict its response. The assessment of the five parameters based on the regression equations substantially increased the sensitivity of IT-MS/MS in the MS/MS mode. The results obtained show that for most of the pesticides, these parameters have a strong influence on both signal response and detection limit.Using the optimized method, a multiclass pesticide analysis was performed for 46 pesticides in a strawberry matrix. Levels higher than the limit established for strawberries by the European Union were found in some samples

    Comparison of Disposable Pipette Extraction and Dispersive Solid-Phase Extraction in the QuEChERS Method for Analysis of Pesticides in Strawberries

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    In this study, we sought to assess the applicability of GC–MS/MS for the identification and quantification of 36 pesticides in strawberry from integrated pest management (IPM) and organic farming (OF). Citrate versions of QuEChERS (quick, easy, cheap, effective, rugged and safe) using dispersive solid-phase extraction (d-SPE) and disposable pipette extraction (DPX) for cleanup were compared for pesticide extraction. For cleanup, a combination of MgSO4, primary secondary amine and C18 was used for both the versions. Significant differences were observed in recovery results between the two sample preparation versions (DPX and d-SPE). Overall, 86% of the pesticides achieved recoveries (three spiking levels 10, 50 and 200 µg/kg) in the range of 70–120%, with <13% RSD. The matrix effects were also evaluated in both the versions and in strawberries from different crop types. Although not evidencing significant differences between the two methodologies were observed, however, the DPX cleanup proved to be a faster technique and easy to execute. The results indicate that QuEChERS with d-SPE and DPX and GC–MS/MS analysis achieved reliable quantification and identification of 36 pesticide residues in strawberries from OF and IPM

    Nano-zero-valent particles synthesized with agroindustry wastes for pesticide degradation under real conditions

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    Nano-zero-valent particles (NZVP) had exhibited high degradation activity. NZVP synthesized from agroindustry residues align with circular economy principles. They generate hydroxyl radicals (4.6 µM) that effectively degraded chlorpyrifos-methyl pesticide under real conditions. Bimetallic NZVP, specifically NZVP-Fe:Mn and NZVP-Fe:Ag, show superior pesticide degradation. The metal ratio within NZVP influences their activity (optimal at 0.12:0.12 mM and 0.12:0.19 mM for respectively, NZVP-Fe:Mn and NZVP-Fe:Ag). NZVP characterization includes TEM, SEM-EDS, PZC, FTIR, XRD, and electrochemical analysis, confirming their acid nature, favorable electrochemical behavior, and uniform metal distribution. The impact of different natural extracts on NZVP synthesis and pesticide degradation was explained through extensive extract characterization, revealing the presence of altering pro-oxidants and scavenger species. Blueberry pruning extract yields the highest pesticide degradation (85% in 5 min) due to its stronger antioxidant activity and lower scavenger compound content. NZVP demonstrates efficacy across various pH ranges. Real wastewater samples were treated under optimal conditions, resulting in a pesticide degradation efficiency of approximately 60% within 5 min. The most effective approach for enhancing the treatment process involved the sequential addition of reagents, as opposed to the conventional method of increasing reagent concentrationXunta de Galicia | Ref. ED481B 2019/091Fundação para a Ciência e a Tecnologia | Ref. UIDB/50006/2020Fundação para a Ciência e a Tecnologia | Ref. UIDP/50006/2020Fundação para a Ciência e a Tecnologia | Ref. LA/P/0008/2020Ministerio de Ciencia e Innovación | Ref. PCI2022-132941Universidade de Vigo/CISUGFundação para a Ciência e a Tecnologia | Ref. CEECIND/02702/201

    Analysis of pesticide residues in strawberries and soils by GC-MS/MS, LC-MS/MS and two-dimensional GC-timeof- flight MS comparing organic and integrated pest management farming

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    This study analysed 22 strawberry and soil samples after their collection over the course of 2 years to compare the residue profiles from organic farming with integrated pest management practices in Portugal. For sample preparation, we used the citrate-buffered version of the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. We applied three different methods for analysis: (1) 27 pesticides were targeted using LC-MS/MS; (2) 143 were targeted using low pressure GC-tandem mass spectrometry (LP-GC-MS/MS); and (3) more than 600 pesticides were screened in a targeted and untargeted approach using comprehensive, two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF-MS). Comparison was made of the analyses using the different methods for the shared samples. The results were similar, thereby providing satisfactory confirmation of both similarly positive and negative findings. No pesticides were found in the organic-farmed samples. In samples from integrated pest management practices, nine pesticides were determined and confirmed to be present, ranging from 2 μg kg−1 for fluazifop-pbutyl to 50 μg kg−1 for fenpropathrin. Concentrations of residues in strawberries were less than European maximum residue limits

    Persistent organic pollutant levels in human visceral and subcutaneous adipose tissue in obese individuals - Depot differences and dysmetabolism implications

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    Background: The role of persistent organic pollutants (POPs) with endocrine disrupting activity in the aetiology of obesity and other metabolic dysfunctions has been recently highlighted. Adipose tissue (AT) is a common site of POPs accumulation where they can induce adverse effects on human health. Objectives: To evaluate the presence of POPs in human visceral (vAT) and subcutaneous (scAT) adipose tissue in a sample of Portuguese obese patients that underwent bariatric surgery, and assess their putative association with metabolic disruption preoperatively, as well as with subsequent body mass index (BMI) reduction. Methods: AT samples (n=189) from obese patients (BMI ≥35) were collected and the levels of 13 POPs were determined by gas chromatography with electron-capture detection (GC-ECD). Anthropometric and biochemical data were collected at the time of surgery. BMI variation was evaluated after 12 months and adipocyte size was measured in AT samples. Results: Our data confirm that POPs are pervasive in this obese population (96.3% of detection on both tissues), their abundance increasing with age (RS=0.310, p<0.01) and duration of obesity (RS=0.170, p<0.05). We observed a difference in AT depot POPs storage capability, with higher levels of ΣPOPs in vAT (213.9±204.2 compared to 155.1±147.4 ng/g of fat, p<0.001), extremely relevant when evaluating their metabolic impact. Furthermore, there was a positive correlation between POP levels and the presence of metabolic syndrome components, namely dysglycaemia and hypertension, and more importantly with cardiovascular risk (RS=0.277, p<0.01), with relevance for vAT (RS=0.315, p<0.01). Finally, we observed an interesting relation of higher POP levels with lower weight loss in older patients. Conclusion: Our sample of obese subjects allowed us to highlight the importance of POPs stored in AT on the development of metabolic dysfunction in a context of obesity, shifting the focus to their metabolic effects and not only for their recognition as environmental obesogens

    Association of 3-Phenoxybenzoic Acid Exposure during Pregnancy with Maternal Outcomes and Newborn Anthropometric Measures: Results from the IoMum Cohort Study

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    The aims of this study were to characterize the exposure of pregnant women living in Portugal to 3-phenoxybenzoic acid (3-PBA) and to evaluate the association of this exposure with maternal outcomes and newborn anthropometric measures. We also aimed to compare exposure in summer with exposure in winter. Pregnant women attending ultrasound scans from April 2018 to April 2019 at a central hospital in Porto, Portugal, were invited to participate. Inclusion criteria were: gestational week between 10 and 13, confirmed fetal vitality, and a signature of informed consent. 3-PBA was measured in spot urine samples by gas chromatography with mass spectrometry (GC-MS). The median 3-PBA concentration was 0.263 (0.167; 0.458) μg/g creatinine (n = 145). 3-PBA excretion was negatively associated with maternal pre-pregnancy body mass index (BMI) (p = 0.049), and it was higher during the summer when compared to winter (p < 0.001). The frequency of fish or yogurt consumption was associated positively with 3-PBA excretion, particularly during the winter (p = 0.002 and p = 0.015, respectively), when environmental exposure is low. Moreover, 3-PBA was associated with levothyroxine use (p = 0.01), a proxy for hypothyroidism, which could be due to a putative 3-PBA—thyroid hormone antagonistic effect. 3-PBA levels were not associated with the anthropometric measures of the newborn. In conclusion, pregnant women living in Portugal are exposed to 3-PBA, particularly during summer, and this exposure may be associated with maternal clinical features.This article was supported by national funds through the FCT Foundation for Science and Technology, I.P., within the scope of the projects RISE - LA/P/0053/2020; CINTESIS, R&D UNIT (reference UIDB/4255/2020) and LAQV (references: UIDB/50006/2020 AND UIDP/50006/2020). Virgínia Cruz Fernandes was funded by FCT/MCTES (Foundation for Science and Technology and Ministry of Science, Technology and Higher Education) and the ESF (European Social Fund) through NORTE 2020 (North Region Operational Program) through a grant of Post-Doc (reference SFRH/BPD/109153/2015). Juliana Guimarães was funded by FCT/MCTES (Foundation for Science and Technology and Ministry of Science, Technology and Higher Education) under CINTESIS by a PhD scholarship (reference UI/BD/152087/2021). The authors would like to thank the kind participation of all pregnant women and the support of the recruitment activities by the health professionals of the Department of Obstetrics, Centro Hospitalar Universitário S. João, Porto, Portugal and also to the professionals of REQUIMTE/LAQV, Instituto Superior de Engenharia, Politécnico do Porto, for their collaboration in carrying out the analyzes of the 3-PBA metabolite. This work received support from PT national funds (FCT/MCTES, Fundação para a Ciência e Tecnologia and Ministério da Ciência, Tecnologia e Ensino Superior) through the projects LA/P/0053/2020; UIDB/4255/2020; UIDB/5006/2020 and UIDP/50006/2020. Virgínia Cruz Fernandes thanks FCT/MCTES (Fundação para a Ciência e Tecnologia and Ministério da Ciência, Tecnologia e Ensino Superior) and ESF (European Social Fund) through NORTE 2020 (Programa Operacional Região Norte) for his/her Post-Doc grant ref. SFRH/BPD/109153/2015). Juliana Guimarães was funded by FCT/MCTES (Foundation for Science and Technology and Ministry of Science, Technology and Higher Education) under CINTESIS by a PhD scholarship (reference UI/BD/152087/2021).info:eu-repo/semantics/publishedVersio

    Persistent organic pollutant levels in human visceral and subcutaneous adipose tissue in obese individuals - Depot differences and dysmetabolism implications

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    Background: The role of persistent organic pollutants (POPs) with endocrine disrupting activity in the aetiology of obesity and other metabolic dysfunctions has been recently highlighted. Adipose tissue (AT) is a common site of POPs accumulation where they can induce adverse effects on human health. Objectives: To evaluate the presence of POPs in human visceral (vAT) and subcutaneous (scAT) adipose tissue in a sample of Portuguese obese patients that underwent bariatric surgery, and assess their putative association with metabolic disruption preoperatively, as well as with subsequent body mass index (BMI) reduction. Methods: AT samples (n=189) from obese patients (BMI ≥35) were collected and the levels of 13 POPs were determined by gas chromatography with electron-capture detection (GC-ECD). Anthropometric and biochemical data were collected at the time of surgery. BMI variation was evaluated after 12 months and adipocyte size was measured in AT samples. Results: Our data confirm that POPs are pervasive in this obese population (96.3% of detection on both tissues), their abundance increasing with age (RS=0.310, p<0.01) and duration of obesity (RS=0.170, p<0.05). We observed a difference in AT depot POPs storage capability, with higher levels of ΣPOPs in vAT (213.9±204.2 compared to 155.1±147.4 ng/g of fat, p<0.001), extremely relevant when evaluating their metabolic impact. Furthermore, there was a positive correlation between POP levels and the presence of metabolic syndrome components, namely dysglycaemia and hypertension, and more importantly with cardiovascular risk (RS=0.277, p<0.01), with relevance for vAT (RS=0.315, p<0.01). Finally, we observed an interesting relation of higher POP levels with lower weight loss in older patients. Conclusion: Our sample of obese subjects allowed us to highlight the importance of POPs stored in AT on the development of metabolic dysfunction in a context of obesity, shifting the focus to their metabolic effects and not only for their recognition as environmental obesogens
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