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Mancozeb is a widely used fungicide whose toxicity has been reported in non-target organisms, being considered to have high or very high acute toxicity to aquatic organisms. However, the toxicity of this compound is not well characterized in the developmental stages of fish. In this study, Danio rerio with 4-, 5-, and 6-days post fertilization (dpf) was exposed to MZ at non-lethal concentrations for 24, 48, or 72 h and subsequently, behavioral alterations, oxidative stress parameters and ERK, p38MAPK, and Akt phosphorylation were analyzed. MZ exposure during the larval period decreased motor performance evaluated by traveled distance, immobile time, and time spent in the peripheral area. In parallel, MZ induced ROS levels and increased the number of cells in apoptosis, causing severe DNA damage, inducing Acetylcholinesterase and Superoxide dismutase activities, and inhibiting Glutathione peroxidase and thioredoxin reductase. Additionally, phosphorylation levels of the proteins p38MAPK, ERK2, and Akt were stimulated. These findings are relevant considering the ecological implications of MZ exposure to fishes in different developmental stages and the role of the MAPK pathway in events like development and cell death.

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Pesticides are a suitable tool for controlling plagues and disease vectors. However, their inappropriate use allows for contamination of the environment, soil, water, and foods. Carbamates and dithiocarbamates pesticides present accumulative effects in the human body resulting in hormonal, neurological and reproductive disorders, and some are still suspected or proven to give carcinogenic or mutagenic effects. This review provides a current electroanalytical approach in the carbamates and dithiocarbamates determination, showing the use of voltammetric techniques such as amperometry, cyclic and linear scan, differential pulse, and square wave voltammetry, indicating their advantages, disadvantages, and perspectives in electroanalytical detection of carbamates and dithiocarbamates in natural water and foods. Also are reported the different materials used in the preparation of working electrodes since their choice has an important impact on the success of the analytical applications, resulting in suitable sensitivity, selectivity, stability, and robustness.

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Food matrices consist of many components with different physical and chemical properties that may influence instrumental robustness. The soybean contains fatty coextractives which may have a deleterious effect on the gas chromatography (GC) system. In this study, the efficiencies of PSA, C18OH, C18, silica, aluminum oxide, and Florisil, as dSPE clean-up sorbents, were evaluated by the high-performance liquid chromatography (HPLC) diode-array detector and evaporative light-scattering detector analysis. The dithiocarbamates in soybean samples are determined as CS2 using acidic hydrolysis and isooctane partitioning, followed by GC-PFPD and GC-ITD-MS analyses. The linearity of the analytical curves, the instrument limit of detection matrix effects, the trueness and precision, and the method limit of quantification (LOQ) were assessed in the validation study. Milled soybean was spiked with thiram solution at three concentration levels (corresponding to 0.05, 0.1, and 0.5 mg CS2 kg-1) for recovery determination. Silica appeared to be an effective and cheap sorbent to remove coextracted matrix components without causing any CS2 losses. Recoveries were in the range of 68-91%, with relative standard deviations ≤ 8.7%. The method LOQ was 0.05 mg CS2 kg-1, and both GC-ITD-MS and GC-PFPD systems appeared to be appropriate and complementary to determine dithiocarbamate residues in soybean extracts.

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Dithiocarbamates represent a class of compounds that were evaluated in different biomedical applications because of their chemical versatility. For this reason, several pharmacological activities have already been attributed to these compounds, such as antiparasitic, antiviral, antifungal activities, among others. Therefore, compounds that are based on dithiocarbamates have been evaluated in different in vivo and in vitro models as potential new antimicrobials. Thus, the purpose of this review is to present the possibilities of using dithiocarbamate compounds as potential new antitrypanosomatids-drugs, which could be used for the pharmacological control of Chagas disease, leishmaniasis, and African trypanosomiasis.

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Residue data for triazoles (TR) and dithiocarbamates (DT) in 30,786 samples of 30 foods were obtained from mainly two national monitoring programs, and consumption data from a national survey conducted among persons aged 10 years or older. About 16% of the samples contained TR, mainly grape (53.5%), and 16.2% contained DT, mainly apple (59.3%). Flusilazole was the index compound used for the acute effects of TR for women of child-bearing-age (cranium-facial malformation and skeletal variation), cyproconazole for the chronic effects of TR (hepatoxicity), and ethylene-bis-dithitiocarbamates (EBDC) for DT (thyroid toxicity). Exposures were estimated using the Monte Carlo Risk Assessment software. Different models were tested, and a Model-Then-Add approach was found to best estimate the chronic exposures to DT and TR. At the 99.9th percentile (P99.9), the cumulative acute TR intakes accounted for up to 0.5% of the flusilazole ARfD, mainly from beans and rice consumption. The chronic TR and DT intakes accounted for 1 and 6.7% of the respective index compound ADIs, with beans and rice accounting for most of the TR intake (∼70%), and apple for about 51-56% of the DT intake. The estimated risks from the exposure to TR and DT indicate no health concern for the Brazilian population.

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In order to evaluate the efficiency of biobeds on DTC degradation, the aim of this study was to apply, optimize and validate a method to determine dithiocarbamate (mancozeb) in biobeds using gas chromatography-tandem mass spectrometry (GC-MS). The DTC pesticide mancozeb was hydrolysed in a tin (II) chloride solution at 1.5% in HCl (4 mol L-1), during 1 h in a water bath at 80 °C, and the CS2 formed was extracted in isooctane. After cooling, 1 mL of the organic layer was transferred to an auto sampler vial and analyzed by GC-MS. A complete validation study was performed and the following parameters were assessed: linearity of the analytical curve (r2), estimated method and instrument limits of detection and limits of quantification (LODm, LODi, LOQm and LOQi, respectively), accuracy (recovery%), precision (RSD%) and matrix effects. Recovery experiments were carried out with a standard spiking solution of the DTC pesticide thiram. Blank biobed (biomixture) samples were spiked at the three levels corresponding to the CS2 concentrations of 1, 3 and 5 mg kg-1, with seven replicates each (n = 7). The method presented satisfactory accuracy, with recoveries within the range of 89-96% and RSD ≤ 11%. The analytical curves were linear in the concentration range of 0.05-10 µg CS2 mL-1 (r2 > 0.9946). LODm and LOQm were 0.1 and 0.5 mg CS2 kg-1, respectively, and the calculated matrix effects were not significant (≤ 20%). The validated method was applied to 80 samples (biomixture), from sixteen different biobeds (collected at five sampling times) during fourteen months. Ten percent of samples presented CS2 concentration below the LOD (0.1 mg CS2 kg-1) and 49% of them showed results below the LOQ (0.5 mg CS2 kg-1), which demonstrates the biobeds capability to degrade DTC.

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Os ditiocarbamatos (EBDCs) são substâncias organosulfuradas empregadas na agricultura com ação fungicida. O risco toxicológico destas deve-se a seus dois maiores produtos de degradação: a etileno tiouréia (ETU) e a propilenotiouréia (PTU), suspeitos de serem bociogênicos, carcinogênicos e mutagênicos em ratos. No Brasil, existem registrados seis diferentes tipos de substâncias cujos princípios ativos são da classe química dos ditiocarbamatos, indicados para quarenta e um diferentes tipos de cultura. O uso é intenso, conforme reportado pelo programa gerenciado pela ANVISA, o PARA Programa Nacional de Análise de Resíduos de agrotóxicos em alimentos, que tem o objetivo de monitorar dados para atualização do risco de ingestão diária. A metodologia utilizada para o monitoramento dessas substâncias baseia-se na detecção fotométrica do dissulfeto de carbono (CS2), liberado na hidrólise ácida dos EBDCs contidos nos alimentos. O complexo cúprico amarelo formado é determinado espectrofotometricamente. Apesar da legislação especificar diferentes produtos ditiocarbamatos para diferentes culturas, contempla o seu limite máximo residual em CS2 para todos, não distinguindo as diferentes substâncias utilizadas.(...) Este trabalho mostra os resultados desta cultura de amostras comercializadas no Rio de Janeiro, provenientes dos estados do Espírito Santo, Minas Gerais e Bahia.(AU)

Dithiocarbamates, ethylene bisdithiocarbamates - EBDCs, are a class of fungicides extensively used in agriculture for protection of various crops. The toxicological significance of these compounds residues in food is related to the metabolite or its degradation product, ethylenethiourea - ETU and propylenethiourea - PTU, known to be gointerogenic, carcinogenic and teratotogenic in laboratory animals. There are six dithiocarbamates compounds indicated for forty-one different crops regulated in Brazil. Their use are intense as reported by National Program of Pesticides Residues Analysis in Food (PARA) from National Sanitary Surveillance Agency (ANVISA) that has the objective of check the risk assessment from chronic dietary exposure. The methodology most commonly used by monitoring these compound in food relies on the detection of CS2 generated after acid digestion of any dithiocarbamates present in the crop using spectrophotometry for detection of the yellow cupric complex formed. TheBrazilian Legislation has registered different dithiocarbamates for different crops but does not identify the origin of the CS2 detected so, in this manner, the maximum residue limits (MRL) are indicated as CS2. For papaya crop mancozed is permitted with MRL of 3,0 mg/kg as CS2. In this paper, we have showed preliminary results of evaluation of papaya from Espírito Santo, Minas Gerais and Bahia states that were bought in Rio de Janeiro city. Dithiocarbamates residues were detected, as CS2, in 70 % of samples under MRL permitted. The preliminaryresults gave evidence of the necessity of monitoring in other crops are needed to improve assessment the public health risk from crops treated with dithiocarbamates. (AU)

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