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Journal of Chromatography. A Dec 2021Quantitative determination of targeted and untargeted pesticide residues from food products is very important for the assessment of safety of the food products. In the...
Quantitative determination of targeted and untargeted pesticide residues in coconut milk by liquid chromatography - Atmospheric pressure chemical ionization - high energy collisional dissociation tandem high-resolution mass spectrometry.
Quantitative determination of targeted and untargeted pesticide residues from food products is very important for the assessment of safety of the food products. In the present work, a simple, selective and sensitive method based on liquid chromatography atmospheric pressure chemical ionization high energy collisional dissociation high-resolution tandem mass spectrometry (LC-APCI-HCD-HRMS/MS) for quantification of 19 priority organophosphorus and carbamate pesticides and 10 untargeted pesticides from coconut milk samples was developed and validated. The pesticide residues were extracted by solvent partition followed by dispersive solid-phase extraction clean-up and quantified by LC-APCI-HRMS/MS technique. The method showed the linearity for targeted pesticides in the range of 0.5-1000 ng/g with a limit of detection of ranging 0.5-5 ng/g and limit of quantification of ranging 1-10 ng/g measured at 3:1 and 10:1 signal to noise ratios, respectively. The untargeted pesticide residues were quantified by the response factor method. The method was validated for intraday and interday precision, which was less than 15%. The recovery of the analytes varied between 82 and 117%, and the developed method was applied for the analysis of the coconut milk samples. The analyzed samples showed the presence of quinalphos, malathion, and methiocarb at concentrations of 4.55, 5.54, and 206.99 ng/g.
Topics: Animals; Atmospheric Pressure; Chromatography, High Pressure Liquid; Chromatography, Liquid; Cocos; Pesticide Residues; Tandem Mass Spectrometry
PubMed: 34742133
DOI: 10.1016/j.chroma.2021.462649 -
The Science of the Total Environment Feb 2022The presence of micropollutants (MPs), including pharmaceutical, industrial, and pesticidal compounds, threatens both human health and the aquatic ecosystem. The...
The presence of micropollutants (MPs), including pharmaceutical, industrial, and pesticidal compounds, threatens both human health and the aquatic ecosystem. The development and extensive use of new chemicals have also inevitably led to the accumulation of MPs in aquatic environments. Recreational beaches are especially vulnerable to contamination, affecting humans and aquatic animals via the absorption of MPs in water during marine activities (e.g., swimming, sailing, and windsurfing). Additionally, marine outfalls in an urbanized coastal city can cause serious chemical and microbial pollution on recreational beaches, leading to an increase in adverse effects on public health and the ecological system. Therefore, the aim of this study was to, with the use of network and decision tree analyses, identify the features and factors that influence the change in MP concentrations in a marine outfall. These analyses were conducted to inspect the relationship between each MP and its hierarchical structure as well as hydrometeorological variables. Additionally, a risk analysis was conducted in this study in which the MPs were prioritized based on their optimized risk quotient values. During our monitoring of MP concentrations over time at the marine outfall, high concentrations of pharmaceutical and industrial compounds were detected when the tide level was low after rainfall. Furthermore, results of the risk analysis and the prioritization revealed that a total of 18 substances identified in our study posed a risk to the ecosystem; these include major ecotoxicologically hazardous substances such as telmisartan, mevinphos, and methiocarb. Results of the network analysis demonstrated distinct trends for pharmaceutical and industrial substances, whilst those for pesticide compounds were irregular. Additionally, the hierarchical structures for most MPs consisted of rainfall, tide level, and antecedent dry hours; this implies that these factors influence MP dynamics. These findings will be helpful for establishing chemical contamination management plans for recreational beaches in the future.
Topics: Animals; Decision Trees; Ecosystem; Environmental Monitoring; Humans; Pesticides; Water Pollutants, Chemical
PubMed: 34655621
DOI: 10.1016/j.scitotenv.2021.150938 -
Scientific Reports Jul 2021Carbon xerogels (CXs) were synthesized by polycondensation of resorcinol and formaldehyde, followed by thermal annealing, and subjected to hydrothermal oxidation....
Carbon xerogels (CXs) were synthesized by polycondensation of resorcinol and formaldehyde, followed by thermal annealing, and subjected to hydrothermal oxidation. Solid-phase extraction (SPE) cartridges were filled with CXs and tested for extraction of metaflumizone and other seven environmental micropollutants (acetamiprid, atrazine, isoproturon, methiocarb, carbamazepine, diclofenac, and perfluorooctanesulfonic acid) before chromatographic analysis. The recoveries obtained with the pristine CX were low for most analytes, except for metaflumizone (69 ± 5%). Moreover, it was concluded that the adsorption/desorption process of the micropollutants performed better on CXs with a less acidic surface (i.e., pristine CX). Thus, cartridges were prepared with pristine CX and multi-walled carbon nanotubes (MWCNTs) in a multi-layer configuration. This reusable cartridge was able to simultaneously extract the eight micropollutants and was used to validate an analytical methodology based on SPE followed by ultra-high performance liquid chromatography-tandem mass spectrometry. A widespread occurrence of 6/8 target compounds was observed in surface water collected in rivers supplying three drinking water treatment plants and in the resulting drinking water at the endpoint of each distribution system. Therefore, the first study employing CXs and MWCNTs as sorbent in multi-layer SPE cartridges is herein reported as a proof of concept for determination of multi-class water micropollutants.
PubMed: 34226575
DOI: 10.1038/s41598-021-93163-2 -
Insects Jun 2021Terrestrial gastropod molluscs (slugs and snails) (Mollusca: Gastropoda) cause significant crop damage around the world. There is no formal approach for differentiating... (Review)
Review
Terrestrial gastropod molluscs (slugs and snails) (Mollusca: Gastropoda) cause significant crop damage around the world. There is no formal approach for differentiating between slugs and snails; however, an organism is usually considered a slug when there is no external shell, or when the shell is small in comparison to the body, and a snail when there is a large external shell. Although snails are an important pest of many crops, this review focuses on slug pests and their nonchemical control measures. A recent study by the UK Agriculture and Horticulture Development Board concluded that the failure to control slugs could cost the UK agriculture industry over GBP 100 million annually, with similar figures reported around the world. Whilst slugs are mostly controlled using chemical molluscicide products, some actives have come under scrutiny due to their detrimental environmental effects and impact on nontarget organisms. This has resulted in the ban of actives such as methiocarb in the UK and EU, and, more recently, the ban of metaldehyde in the UK. Therefore, there is an urgent need to find alternative and effective nontoxic solutions in the interest of global food security. In this paper, we have integrated extant literature on the three main biological control agents of slugs, namely nematodes, carabid beetles and sciomyzid flies, and various promising bio-rational slug control strategies. The review also highlights current research gaps and indicates some relevant potential future directions towards developing environmentally benign slug control solutions.
PubMed: 34200919
DOI: 10.3390/insects12060541 -
Journal of Colloid and Interface Science May 2021Present work reports preparation of colloidal single/few layer TiCT MXene flakes using minimally intensive layer delamination (MILD) method for rapid electroanalytical...
Present work reports preparation of colloidal single/few layer TiCT MXene flakes using minimally intensive layer delamination (MILD) method for rapid electroanalytical screening of carbamate pesticides. Lithium fluoride salt and hydrochloric acid (7.5 M LiF/9M HCl) was used to produce in-situ generated HF as etchant to remove Al successfully from TiAlC MAX phase. Unlike the clay method (5 M LiF/6M HCl), this methodology simplified TiCT synthesis protocol resulting in Li ions intercalated TiCT which was delaminated without further sonication. The delaminated TiCT flakes were found to be single/few layered sheets with mostly -OH and -O terminated surface groups. The characteristic 002 peak observed in X-ray diffraction (XRD) at 2θ = 6.4° with interplaner distance of 1.1137 nm suggested broadening of the peak attributed to the presence of Li ions between TiCT flakes. Delaminated TiCT flakes were utilized as working electrode which demonstrated simultaneous and selective detection of carbamate pesticides methiocarb and diethofencarb by voltammetry. The oxidation peaks of the two pesticides were well separated by a potential difference of 0.35 V in 0.5 M HSO and DPV detection limits were calculated as 0.19 μg mL and 0.46 μg mL for methiocarb and diethofencarb respectively. TiCT flakes as electrochemical sensor exhibited long term stability and acceptable recoveries in real sample for environmental applications.
PubMed: 33549895
DOI: 10.1016/j.jcis.2021.01.063 -
Frontiers in Veterinary Science 2020Nowadays the intentional poisoning of domestic and wild animals is a crime in the European Union (EU), but as in the past the poison is still used in rural areas of a...
Nowadays the intentional poisoning of domestic and wild animals is a crime in the European Union (EU), but as in the past the poison is still used in rural areas of a number of European countries to kill animals that were considered harmful for human activities. From January 2014 up until October 2020, the Laboratory of Pharmacology and Toxicology of the Faculty of Veterinary Medicine (LFT-FMV) has done the analytical detection of poisoning substances in 503 samples of wildlife and domestic animals and pesticides residues were found in 239 of the samples analyzed. In this retrospective study, toxicology results from domestic species (dog, cat, sheep, cows, and horses), wildlife species (red foxes, birds of prey, lynx, and wild boar), and food baits, are presented. During this period the samples analyzed at the LFT-FMV, were received from all over the country. Analytical detections were performed via solvent extraction followed by thin layer chromatography. Molluscicides (47%, = 109) and Carbamates (24%, = 57) were found to be the first category of pesticides involved in intoxications, in both domestic and wild animals, followed by rodenticides (13%, = 30)-in this group second and third generation, were the most represented; Strychnine is the third (11%, = 26) even though this pesticide has been banned in Portugal since 1988 and in the European Union since 2006 and finally Organophosphates (5%, = 11) in the small number. This study allowed to realize that a great number of positive samples involved banned pesticides (i.e., Aldicarb and Strychnine) but, at the same time, many positives cases were due to the exposure to commercially available products (i.e., Methiocarb and Anticoagulant rodenticides). Also, it's possible to identify the areas where domestic species are the most affected (i.e., Setubal and Lisboa) and the areas where the wild animals are the mainly affected species (i.e., Faro, Castelo Branco, and Bragança).
PubMed: 33521089
DOI: 10.3389/fvets.2020.616293 -
Scientific Reports Dec 2020Pristine and functionalized multi-walled carbon nanotubes (MWCNTs) were investigated as adsorbent materials inside solid-phase extraction (SPE) cartridges for extraction...
Pristine and functionalized multi-walled carbon nanotubes (MWCNTs) were investigated as adsorbent materials inside solid-phase extraction (SPE) cartridges for extraction and preconcentration of 8 EU-relevant organic micropollutants (with different pKa and polarity) before chromatographic analysis of surface water. The recoveries obtained were > 60% for 5/8 target pollutants (acetamiprid, atrazine, carbamazepine, diclofenac, and isoproturon) using a low amount of this reusable adsorbent (50 mg) and an eco-friendly solvent (ethanol) for both conditioning and elution steps. The introduction of oxygenated surface groups in the carbon nanotubes by using a controlled HNO hydrothermal oxidation method, considerably improved the recoveries obtained for PFOS (perfluorooctanesulfonic acid) and methiocarb, which was ascribed to the hydrogen bond adsorption mechanism, but decreased those observed for the pesticide acetamiprid and for two pharmaceuticals (carbamazepine and diclofenac), suggesting π-π dispersive interactions. Moreover, a good correlation was found between the recovery obtained for methiocarb and the amount of oxygenated surface groups on functionalized MWCNTs, which was mainly attributed to the increase of phenols and carbonyl and quinone groups. Thus, the HNO hydrothermal oxidation method can be used to finely tune the surface chemistry (and texture) of MWCNTs according to the specific micropollutants to be extracted and quantified in real water samples.
PubMed: 33339850
DOI: 10.1038/s41598-020-79244-8 -
Molecules (Basel, Switzerland) Dec 2020This paper studies the degradation of methiocarb, a highly hazardous pesticide found in waters and wastewaters, through an electro-Fenton process, using a boron-doped...
This paper studies the degradation of methiocarb, a highly hazardous pesticide found in waters and wastewaters, through an electro-Fenton process, using a boron-doped diamond anode and a carbon felt cathode; and evaluates its potential to reduce toxicity towards the model organism . The influence of applied current density and type and concentration of added iron source, Fe(SO)·5HO or FeCl·6HO, is assessed in the degradation experiments of methiocarb aqueous solutions. The experimental results show that electro-Fenton can be successfully used to degrade methiocarb and to reduce its high toxicity towards . Total methiocarb removal is achieved at the applied electric charge of 90 C, and a 450× reduction in the acute toxicity towards , on average, from approximately 900 toxic units to 2 toxic units, is observed at the end of the experiments. No significant differences are found between the two iron sources studied. At the lowest applied anodic current density, 12.5 A m, an increase in iron concentration led to lower methiocarb removal rates, but the opposite is found at the highest applied current densities. The highest organic carbon removal is obtained at the lowest applied current density and added iron concentration.
Topics: Animals; Biodegradation, Environmental; Daphnia; Ecotoxicology; Electrochemistry; Electrodes; Insecticides; Methiocarb; Water Pollutants, Chemical
PubMed: 33322793
DOI: 10.3390/molecules25245893 -
Science (New York, N.Y.) Oct 2020
Topics: Animals; Endangered Species; Guinea-Bissau; Insecticides; Kenya; Methiocarb; Raptors
PubMed: 33060355
DOI: 10.1126/science.abd1862 -
PloS One 2020In bovine mammary glands, the ABCG2 transporter actively secretes xenobiotics into dairy milk. This can have significant implications when cattle are exposed to...
In bovine mammary glands, the ABCG2 transporter actively secretes xenobiotics into dairy milk. This can have significant implications when cattle are exposed to pesticide residues in feed. Recent studies indicate that the fungicide prochloraz activates the aryl hydrocarbon receptor (AhR) pathway, increasing bovine ABCG2 (bABCG2) gene expression and efflux activity. This could enhance the accumulation of bABCG2 substrates in dairy milk, impacting pesticide risk assessment. We therefore investigated whether 13 commonly used pesticides in Europe are inducers of AhR and bABCG2 activity. MDCKII cells expressing mammary bABCG2 were incubated with pesticides for up to 72 h. To reflect an in vivo situation, applied pesticide concentrations corresponded to the maximum residue levels (MRLs) permitted in bovine fat or muscle. AhR activation was ascertained through CYP1A mRNA expression and enzyme activity, measured by qPCR and 7-ethoxyresorufin-Ο-deethylase (EROD) assay, respectively. Pesticide-mediated increase of bABCG2 efflux activity was assessed using the Hoechst 33342 accumulation assay. For all assays, the known AhR-activating pesticide prochloraz served as a positive control, while the non-activating tolclofos-methyl provided the negative control. At 10-fold MRL concentrations, chlorpyrifos-methyl, diflufenican, ioxynil, rimsulfuron, and tebuconazole significantly increased CYP1A1 mRNA levels, CYP1A activity, and bABCG2 efflux activity compared to the vehicle control. In contrast, dimethoate, dimethomorph, glyphosate, iprodione, methiocarb and thiacloprid had no impact on AhR-mediated CYP1A1 mRNA levels, CYP1A activity or bABCG2 efflux. In conclusion, the MDCKII-bABCG2 cell model proved an appropriate tool for identifying AhR- and bABCG2-inducing pesticides. This provides an in vitro approach that could reduce the number of animals required in pesticide approval studies.
Topics: ATP Binding Cassette Transporter, Subfamily G, Member 2; Animal Testing Alternatives; Animals; Cattle; Dogs; Fungicides, Industrial; Germany; Lactation; Madin Darby Canine Kidney Cells; Receptors, Aryl Hydrocarbon; Recombinant Proteins; Toxicity Tests, Chronic
PubMed: 32764792
DOI: 10.1371/journal.pone.0237163