Fungicides In Fruits Research Articles

Enantioselective separation and simultaneous determination of fenarimol and nuarimol in fruits, vegetables, and soil by liquid chromatography–tandem mass spectrometry

A method for simultaneous enantioselective determination of fenarimol and nuarimol in apple, grape, cucumber, tomato, and soil was developed using liquid chromatography-tandem mass spectrometry. The enantioseparation results of the two fungicides through three different cellulose-based chiral columns are discussed. The influence of column temperature on the resolution of the enantiomers of the two fungicides was examined. Complete enantioseparation of the two fungicides' enantiomers was obtained on a cellulose tris(4-methylbenzoate) column (Lux Cellulose-3) at 25 °C using methanol and 0.1 % formic acid solution (80:20, v/v) as mobile phase. The linearity, matrix effect, recovery, and precision were evaluated. Good linearity was obtained over the concentration range of 1-500 μg L(-1) for each enantiomer in the standard solution and sample matrix calibration solution. There was no significant matrix effect in apple, grape, cucumber, or tomato samples, but signal suppression was typically observed with the soil extracts. The mean recoveries, repeatability, and reproducibility were 76.5-103 %, 2.1-9.0 %, and 4.2-11.8 %, respectively. The limit of quantification for enantiomers of the two fungicides in fruits, vegetables and soil was 5 μg kg(-1). Moreover, the absolute configuration of the enantiomers of fenarimol and nuarimol was determined from a combination of experimentally determined and predicted electronic circular dichroism spectra.

Surveillance of fungicidal dithiocarbamate residues in fruits and vegetables

Derivatisation, solid–liquid extraction, solid-phase purification and HPLC–DAD separation is a simple, fast, and accurate method developed for the determination of dithiocarbamate (DTC) fungicides in fruits and vegetables. Quantification is based on external standard calibration curves made with DTCs-spiked blank-matrices. Limits of detection (LODs) and limits of quantitation (LOQs) are in the range of 0.01–0.3 and 0.02–0.5 mg/kg, respectively. Recoveries higher than 78% were obtained for the target DTCs in all the commodities studied. The aim of this research was to evaluate the quality and determine the concentrations of DTC fungicide residues in plant material harvested from September to November of 2010. Several fruits and vegetables produced in Spain were collected at small shops and large food chains distributed by the four provinces of Galicia (North-Western Spain). In total, 150 samples were studied (32 apples, 12 wine grapes, 32 lettuces, 32 peppers, 32 tomatoes, and 10 strawberries). Residues of DTCs were found in all the products analysed with the exception of strawberries, being ethylenebis(dithiocarbamates) (EBDCs) vs. propylenebis (dithiocarbamates) (PBDCs) the main contributors to the total pesticide load. Moreover, fungicide residues exceeding maximum residue limits (MRLs) were identified in 6% of the samples analysed, specifically on lettuces and peppers.

Direct analysis of dithiocarbamate fungicides in fruit by ambient mass spectrometry

Dithiocarbamates (DTCs) are fungicides that require a specific single-residue method for detection and verification of compliance with maximum residue limits (MRLs) as established for fruit and vegetables in the EU. In this study, the use of ambient mass spectrometry was investigated for specific determination of individual DTCs (thiram, ziram) in fruit. Two complementary approaches have been investigated for their rapid analysis: (i) direct analysis in real time (DART) combined with medium-high resolution/accurate mass time-of-flight mass spectrometry (TOFMS) and high-resolution/accurate mass Orbitrap MS, and (ii) desorption electrospray ionization (DESI) combined with tandem-in-time mass spectrometry (MS2). With both techniques, thiram deposited on a glass surface (DART) or Teflon (DESI) could be directly detected. With DART, this was also possible for ziram. Before the instrumental analysis of fruit matrix, an extract had to be prepared following a straightforward procedure. The raw extracts were deposited on a slide (DESI), or rods were dipped into the extracts (DART), after which thiram and ziram could be rapidly detected (typically 10 samples in a few minutes). In the case of thiram, the lowest calibration levels were 1 mg kg−1 (DART–TOFMS, DESI–MS2) and 0.1 mg kg−1 (DART–Orbitrap MS). For ziram, the achieved lowest calibration levels were 0.5 mg kg−1 (DART–TOFMS) and 1 mg kg−1 (DART–Orbitrap MS). In all cases, this was sufficiently low to test samples against EU-MRLs for a number of fruit crops. Using an internal standard, (semi)quantitative results could be obtained.

Liquid–liquid microextraction methods based on ultrasound-assisted emulsification and single-drop coupled to gas chromatography–mass spectrometry for determining strobilurin and oxazole fungicides in juices and fruits

Two procedures are proposed based on ultrasound-assisted emulsification and single-drop liquid–liquid microextraction for the sensitive determination of seven strobilurin and six oxazole fungicides in fruits and juice samples. Both miniaturized techniques are coupled to gas chromatography with mass spectrometry in the selected ion monitoring mode, GC–MS(SIM). The procedures use low density organic solvents, and several factors influencing the emulsification, extraction and collection efficiency are optimized. The detection limits obtained at a signal-to-noise ratio of 3 are below the MRLs set by the European Commission. Enrichment factors are between 140–1140 for the first technique used and 80–1600 for the latter. The recoveries obtained for spiked samples are satisfactory for all compounds. The methods are validated according to the Commission Decision 2002/657/EC. Different fruit and juices are analyzed by the proposed method and none of the samples contained fungicide residues above the detection limits.

MULTI-RESIDUE METHOD OF NINE FUNGICIDES IN FRUITS AND VEGETABLES EMPLOYING DISPERSIVE SOLID-PHASE EXTRACTION AND HPLC/MS DETECTION

A multi-residue analysis method for nine fungicides in fruits and vegetables was developed. Samples were extracted with acetonitrile in the presence of anhydrous MgSO 4 and NaCl; and then cleaned up by reversed dispersive solid-phase extraction (dispersive-SPE) with primary secondary amine (PSA) as main sorbent, with MgSO 4 and activated carbon for auxiliary reagents. A monolithic column was compared with the packed column in LC separation. The linear range was from 0.02 to 5 mg L -1 and regression coefficients were >0.995 with relative standard deviations relative standard deviations (R.S.Ds) less than 2%. Six kinds of extracts from apple, pear, grape, tomato, cucumber and lettuce were selected as typical categories and spiked at 0.02, 0.1, 1 mg kg -1 levels. Recoveries of the nine fungicides were between 74% and 110%. LOQs of these pesticides can meet the requirements of MRL compliance check.

Disposable pipette extraction for the analysis of pesticides in fruit and vegetables using gas chromatography/mass spectrometry

Organochlorine, organophosphate pesticides and fungicides in fruits and vegetables were analyzed using disposable pipette extraction (DPX) followed by gas chromatography–mass spectrometry-selective ion monitoring (GC/MS-SIM). The intrinsic rapid mixing capabilities of DPX result in fast and efficient extractions, and eluates are concentrated by using minimal elution solvent volumes rather than solvent evaporation methods. Matrix-matched calibrations were performed with reversed phase mechanisms (DPX-RP), and the limits of detection (LOD) were determined to be lower than 0.1 μg/mL for all targeted pesticides in carrot and orange sample matrices. Coefficients of determination ( r 2) were greater than 0.995 for most studied pesticides. DPX-RP exhibited recoveries between 72 and 116% for nonpolar and slightly polar pesticides (log P > 2) with most of the recoveries over 88%. Only very polar pesticides (e.g., acephate, mathamidophos) were not extracted well using DPX-RP.

Determination of benzimidazolic fungicides in fruits and vegetables by supramolecular solvent-based microextraction/liquid chromatography/fluorescence detection

A supramolecular solvent consisting of vesicles, made up of equimolecular amounts of decanoic acid (DeA) and tetrabutylammonium decanoate (Bu 4NDe), dispersed in a continuous aqueous phase, is proposed for the extraction of benzimidazolic fungicides (BFs) from fruits and vegetables. Carbendazim (CB), thiabendazole (TB) and fuberidazole (FB) were extracted in a single step and no clean-up or concentration of extracts was needed. The high extraction efficiency obtained for BFs was a result of the different types of interactions provided by the supramolecular solvent (e.g. hydrophobic and hydrogen bonds) and the high number of solubilisation sites it contains. Besides simple and efficient, the proposed extraction approach was rapid, low-cost, environment friendly and it was implemented using conventional lab equipments. The target analytes were determined in the supramolecular extract by LC/fluorescence detection. They were separated in a Kromasil C 18 (5 μm, 150 mm × 4.6 mm) column using isocratic elution [mobile phase: 60:40 (v/v) 50 mM phosphate buffer (pH 4)/methanol] and quantified at 286/320 nm (CB) and 300/350 nm (TB and FB) excitation/emission wavelengths, respectively. Quantitation limits provided by the supramolecular solvent-based microextraction (SUSME)/LC/fluorescence detection proposed method for the determination of CB, TB and FB in fruits and vegetables were 14.0, 1.3 and 0.03 μg kg −1, respectively, values far below the current maximum residue levels (MRLs) established by the European Union, i.e. 100–2000 μg kg −1 for CB, 50–5000 μg kg −1 for TB and 50 μg kg −1 for FB. The precision of the method, expressed as relative standard deviation, for inter-day measurements ( n = 13) was 3.3% for CB (50 μg kg −1), 3.5% for TB (10 μg kg −1) and 2.8% for FB (0.5 μg kg −1) and recoveries for fruits (oranges, tangerines, lemons, limes, grapefruits, apples, pears and bananas) and vegetables (potatoes and lettuces) fortified at the μg kg −1 level were in the interval 93–102%.

Simple and rapid method for the determination of ethylenebisdithiocarbamate fungicides in fruits and vegetables using liquid chromatography with tandem mass spectrometry

A simple and rapid method for determining ethylenebisdithiocarbamates (EBDCs; mancozeb, maneb, and zineb) in fruits and vegetables is described. EBDCs are transformed into dimethylethylenebisdithiocarbamate (EBDC-dimethyl) by methylation after their decomposition with ethylenediaminetetraacetic acid (EDTA). These processes were performed simultaneously in this method. Dimethyl sulfate was used as the methylation reagent, and acetonitrile extracts obtained from partitioning with anhydrous magnesium sulfate and sodium chloride were subjected to dispersive solid-phase extraction with the primary secondary amine sorbent. Liquid chromatography with tandem mass spectrometry in the positive heated-electrospray ionization mode was used for the determination of EBDC-dimethyl produced from EBDCs. The method was validated at levels of 10, 50, and 100 ng g(-1) maneb as a representative EBDC. The recoveries of the present method were between 71 and 101%. The limits of detection and quantification were 0.24 and 0.8 ng g(-1) maneb, respectively.

Extratos, decoctos e óleos essenciais de plantas medicinais e aromáticas na inibição de Glomerella cingulata e Colletotrichum gloeosporioides de frutos de goiaba

A principal doença da goiaba (Psidium guajava L.), após a colheita, é a antracnose, causada por Glomerella cingulata e Colletotrichum gloeosporioides. Estes patógenos e o resíduo de fungicidas em frutos são considerados os principais problemas para a exportaçãodesta fruta. Neste trabalho, foi avaliado o efeito fungitóxico de extratos, decoctos e óleos essenciais de plantas medicinais e aromáticas, no crescimento micelial dos patógenos, in vitro, recomendados como alternativa para o controle químico em pós-colheita. Os extratos aquosos a 10% e os decoctos (subprodutos da hidrodestilação) foram adicionados em BDA, autoclavados e distribuídos em placas de Petri. Os óleos essenciais foram adicionados em três pontos eqüidistantes nas placas de Petri contendo BDA. Discos dos isolados foram repicados para o centro das placas de Petri. O efeito fungitóxico foi avaliado medindo-se o diâmetro das colônias, quando na testemunha ou em qualquer tratamento os patógenos atingiram a borda da placa. O extrato aquoso e o óleo essencial de cravo-da-Índia inibiram em 100% o crescimento de G. cingulata e C. gloeosporioides, sendo este último totalmente inibido pelo óleo essencial de capim-limão. Os decoctos de alecrim, gengibre, calêndula e laranja (Citrus sinensis) apresentaram potencial de inibição sobre os isolados dos patógenos. No controle de C. gloeosporioides, destacaram-se também os decoctos de marcela, camomila e tagetes. A inibição total ou parcial do crescimento micelial de Glomerella cingulata e Colletotrichum gloeosporioides, in vitro, evidenciou a existência de compostos biologicamente ativos, com efeito fungitóxico nos extratos, decoctos e óleos essenciais de plantas medicinais e aromáticas. Isto indica uma aplicação potencial destes produtos no controle alternativo da antracnose em frutos de goiabeira.

The use of natural antifungal compounds improves the beneficial effect of MAP in sweet cherry storage

Sweet cherry shows severe problems for commercialisation mainly due to incidence of decay and a fast loss of sensory quality, both for fruit and stem. A package has been developed based on the addition of eugenol, thymol, menthol or eucalyptol (pure essential oils) separately to trays sealed with polypropylene bags to generate a modified atmosphere (MAP). In addition, cherries in MAP (without essential oils) were selected and served as controls. All cherries were stored during 16 days at 1 °C and 90% RH. Steady-state atmosphere was reached after 9 days of cold storage with 2–3% of CO 2 and 11–12% of O 2 with no significant differences between treated and control, with the exception of eucalyptol, in which significant increases in CO 2 and decreases of O 2 were obtained. When fruit quality parameters were determined, those treated with eugenol, thymol or menthol showed benefits in terms of reduced weight loss, delayed colour changes and maintenance of fruit firmness compared with control. Stem remained green in treated cherries while they became brown in control. However, cherries packaged with eucalyptol behaved even worst than control cherries, with generation of off-flavours, loss of quality and stem browning. Finally, the microbial analysis showed that all essential oils reduced moulds and yeasts and total aerobic mesophilic colonies by 4- and 2-log CFU compared with control, respectively. In conclusion, the use of MAP in combination with eugenol, thymol or menthol is an effective tool on maintaining cherry fruit quality and reducing the occurrence of decay. Industrial relevance The data presented in this work suggest that the use of pure essential oils (eugenol, thymol or menthol) in combination with modified atmosphere packaging (MAP) is an innovative and useful tool as alternative to the use of synthetic fungicides in fruits and vegetables, especially for those which are highly perishable and have a short shelf-life, as cherries. These compounds have been included in the list of generally recognized as safe (GRAS) compounds by FDA. As far as we know, this is the first paper dealing on the use of natural antifungal compounds and MAP and that these combined technologies confer benefits in fruit storage and retailing, with reduction in spoilage microorganisms, maintenance of cherry quality attributes and extension of shelf-life. The effects of these natural compounds on individual microorganisms, both responsible for spoilage and food-borne pathogens, as well as the minimum concentration to gain effectiveness deserve further research.

Application of matrix solid-phase dispersion to the determination of a new generation of fungicides in fruits and vegetables

A method based on matrix solid-phase dispersion (MSPD) and gas chromatography to determine eight fungicides in fruits and vegetables is described. Fungicide residues were identified and quantified using nitrogen–phosphorus detection and electron-capture detection connected in parallel and confirmed by mass spectrometric detection. The method required 0.5 g of sample, C 18 bonded silica as dispersant sorbent, silica as clean-up sorbent and ethyl acetate as eluting solvent. Recoveries from spiked orange, apple, tomato, artichoke, carrot and courgette samples ranged from 62 to 102% and relative standard deviations were less than 15% in the concentration range 0.05–10 mg kg −1. Detection and quantitation limits ranged 3–30 μg kg −1 and 10–100 μg kg −1, respectively, with linear calibration curves up to 10 mg kg −1. The analytical characteristics of MSPD compared very favourably with the results of a classical multiresidue method, which uses ethyl acetate and anhydrous sodium sulphate for the extraction.

Monitoring of Five Postharvest Fungicides in Fruit and Vegetables by Matrix Solid-Phase Dispersion and Liquid Chromatography/Mass Spectrometry

A method was developed for monitoring dichloran, flutriafol, o-phenylphenol, prochloraz, and tolclofos-methyl in fruits and vegetables, using matrix solid-phase dispersion and liquid chromatography with mass spectrometry detection. The method was used to determine fungicide content in 200 samples of chards, onions, peppers, bananas, lemons, and oranges. Of the samples examined, 54% contained o-phenylphenol with concentrations ranging from 0.005 to 3.34 mg/kg and 35% showed prochloraz in the range of 0.06-1.95 mg/kg. Dichloran, flutriafol, and tolclofos-methyl were detected only occasionally. Only 4% of the samples exceeded the European Union maximum residue limits. The pesticides involved were tolclofos-methyl in 3 samples, o-phenylphenol and flutriafol in 2, and dichloran in one. The calculation of estimated daily intake from these monitoring data showed that dietary intakes were much lower than the acceptable daily intakes established by international agencies.

Selective Trace Determination of Dithiocarbamate Fungicides in Fruits and Vegetables by Reversed-Phase Ion-Pair Liquid Chromatography with Ultraviolet and Electrochemical Detection

The predominant methods for determination of dithiocarbamate fungicides (DTC) have been based on quantitation of carbon disulfide released by hot acid digestion. Because the subgroups of the DTC family differ in their chemical properties and toxicological behavior, selective determination is required. To meet the demand for a fast, simple, and sensitive procedure, a new reversed-phase ion-pair chromatographic method was developed, consisting of surface extraction followed by direct injection into a liquid chromatographic system equipped with ultraviolet and electrochemical detectors, connected in series. The procedure is applicable to residues of N-methyldithiocarbamates (metam-sodium), N,N-dimethyldithiocarbamates (e.g., ziram and ferbam), ethylenebisdithiocarbamates (e.g., nabam, maneb, zineb, and mancozeb), and propylenebisdithiocarbamates (e.g., propineb) in fruits and vegetables. Limits of quantitation, calculated according to the procedure of the Deutsche Forschungsgemeinschaft, are 9, 12, 8, and 12 microg CS2/L for N-methyl-DTC, N,N-dimethyl-DTC, ethylenebis-DTC, and propylenebis-DTC, respectively, when electrochemical detection is used.

Exposure to fungicides in fruit growing: re-entry time as a predictor for dermal exposure.

As part of a European Concerted Action on Male Reproduction Capability an exposure assessment survey was conducted among seasonal workers in the fruit growing sector in the Netherlands. Dermal exposure to the fungicides captan and tolylfluanid was measured using cotton gloves (12 persons) and skin pads on several body parts (12 persons). In addition, a set of exposure data was used from a study conducted recently among Dutch fruit growers. For harvesting activities, re-entry time appeared to be an important determinant of dermal exposure to captan and tolyfluanid. Explained variance of regression models was moderate to high (range 0.30-0.87). For captan, calculated half-life times from the most recent exposure survey were lower (glove data: 5 days; pad data: 6 days) compared with half-life times based on the previously conducted study (11 days). Possible explanations for the discrepancy are discussed. For tolylfluanid, estimated half-life times during harvesting were 2 and 3 days, based on pad and glove data, respectively. Prediction of captan exposure during other crop activities appeared to be far more difficult (explained variance equal to 0.06), although the estimated half-life time was comparable with that for harvesting. The data suggest that re-entry time gives useful information to group workers in broad exposure categories. Nonetheless, it was concluded that large studies are needed to evaluate the importance of re-entry time in more detail.

Exposure to Fungicides in Fruit Growing: Re-Entry Time as a Predictor for Dermal Exposure

Exposure to Fungicides in Fruit Growing: Re-Entry Time as a Predictor for Dermal Exposure

Simplified reversed-phase conditions for the determination of benzimidazole fungicides in fruits by high-performance liquid chromatography with UV detection

An analytical method was developed for determination of benzimidazole fungicides (carbendazim and thiabendazole) in fruits. Analyses were performed by HPLC with simple operating conditions. The use of a Kromasil new-generation silica-based stationary phase needed neither pH regulators nor competing compounds, usually added to the mobile phase to analyse basic compounds on reversed stationary phase. Validation studies proved that the chromatographic method had good repeatability, reproducibility and limit of detection. Sample preparation involved extraction with acetone followed by solvent partitioning with dichloromethane and petroleum ether. Extracts were purified through selective diol-bonded silica cartridges, replacing the usual laborious liquid-liquid partitioning procedure. Validation studies proved that the global method had satisfactory repeatability and recovery. Limits of detection were about 0.06 mg/kg.

Chromatographic analysis of imazalil and carbendazim in fruits method validation and residue monitoring program 1995

A single and simple procedure for the determination of both carbendazim and imazalil is described. The proposed analytical methodology is based on a liquid-liquid extraction with ethyl acetate and further analysis with HPLC-UV in the case of carbendazim, and GC-nitrogen-phosphorus detection in the case of imazalil. Detection levels have been 0.01 mg/kg for carbendazim and 0.005 mg/kg for imazalil. Recoveries have been no less than 77% for carbendazim and 92% for imazalil. The method has been validated with fortified samples at different concentration levels. Different confirmation criteria have been studied and applied in routine analysis. The analytical procedure proposed has been applied to the analysis of 200 fruit samples belonging to the Residue Monitoring of Hygiene Food Program 1995 of the Spanish Ministry of Health, which has been performed in our laboratory. The results obtained have confirmed the viability of the method in routine analysis for these pesticides. A first evaluation of the presence of residues of both fungicides in fruits produced in Spain has been made.

Fully Automated Solid-Phase Extraction Cleanup and On-Line Liquid Chromatographic Determination of Benzimidazole Fungicides in Fruit and Vegetables

Abstract A liquid chromatographic (LC) method using fully automated solid-phase extraction (SPE) sample cleanup and on-line LC analysis was developed for determination of the benzimidazole fungicides car-bendazim and thiabendazole in various crops. Preparation of food samples involved extraction with acetone followed by solvent partitioning with dichloromethane–petroleum ether to draw the analytes into the organic phase. The laborious liquid–liquid partitioning cleanup procedure described in the literature was replaced with a fast SPE cleanup using diol-bonded silica cartridges. Automation of the total procedure was achieved by using a commercially available SPE cleanup apparatus (ASPEC). The cleaned-up extract was injected on-line into an LC system with UV and fluorescence detection in tandem. Chromatographic separations were performed with a methanol–phosphate buffer mobile phase (pH = 7) and different polymeric stationary phases. The polymer-based columns performed better than silica-based columns in separating benzimidazole fungicides, and different columns were compared. Results of validation studies with fortified lettuce and citrus fruit are presented. Shewhart control charts of analytical results of control samples demonstrated good performance of the complete system. Sample throughput (extraction, automated SPE, and on-line LC analysis) was about 50 samples per 24 h. Residues of carbendazim and thiabendazole found during our pesticide residue monitoring program in 1992–1994 are reported.

Gas chromatographic determination of some modern pesticides in fruits

A method was developed for determination for residual amounts of some modern insecticides, acaricides and fungicides in fruits. The pesticides were extracted with methanol and partitioned into chloroform. The extract was purified by column chromatography on sodium sulphate/Florisil/Celite/charcoal. Analysis by gas liquid chromatography with 63Ni electron capture detection was completed successively on a column (150 cm × 4 mm) with 3% SE-30 and a column (150 cm × 2 mm) with 3% OV-17 liquid phase. Recoveries of 17 pesticides from fortified samples of apples ranged from 83.3% to 98.4% for a level of 0.1 mg/kg.

Food Contamination from Environmental Sources

Agricultural and Related Contamination in Foods: An Historical Perspective Food Contamination with Camium in the Environment Food Contamination with Arsenic in the Environment Residues of Dithiocarbamate Fungicides in Fruits, Vegetables and Some Field Crops Pesticide Contamination of Food Environmental Contamination of Food by Nitrosamines Derived from Pesticides Pasteurized Diary Products: The Constraints Imposed by Environmental Contamination Food Residues from Pesticides and Environmental Pollutants Environmental Contaminants in Mexican Foods Use of Organochlorine Pesticides for Pest Control in Buildings: The Effect of Occupants Viral Disease Transmission by Seafood.