Analysis of six fungicides and one acaricide in still and fortified wines using solid-phase microextraction-gas chromatography/tandem mass spectrometry

A multiresidue gas chromatographic method for the determination of six fungicides (captan, chlorthalonil, folpet, iprodione, procymidone and vinclozolin) and one acaricide (dicofol) in still and fortified wines was developed. Solid-phase microextraction (SPME) was chosen for the extraction of the compounds from the studied matrices and tandem mass spectrometry (MS/MS) detection was used. The extraction consists in a solvent free and automated procedure and the detection is highly sensitive and selective. Good linearity was obtained with correlation coefficients of regression (R²) > 0.99 for all the compounds. Satisfactory results of repeatability and intermediate precision were obtained for most of the analytes (RSD ? 20%). Recoveries from spiked wine ranged from 80.1% to 112.0%. Limits of quantification (LOQs) were considerably below the proposed maximum residue limits (MRLs) for these compounds in grapes and below the suggested limits for wine (MRLs/10), with the exception of captan.     

Simultaneous determination of pyrimethanil,cyprodinil, mepanipyrim and its metabolite in fresh and home-processed fruit and vegetables by a QuEChERS method coupled with UPLC-MS/MS

A QuEChERS procedure for the simultaneous determination of pyrimethanil, cyprodinil, mepanipyrim and its metabolite (M31) in fresh and processed fruit and vegetables was developed using ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS). The determination of the four target compounds was achieved in less than 6.0 min using an electrospray ionisation source in positive mode. The limits of detection (LODs) were below 0.4 μg?kg^?1, while the limits of quantification (LOQs) did not exceed 1.5 μg?kg^?1 for all studied matrices. Good linearity of the calibration curves was obtained over the range from 0.002 to 2 mg?kg^?1, with correlation coefficients higher than 0.999. The average recoveries of this method in apple, peach, cabbage and tomato at the five spiked levels (0.002, 0.01, 0.05, 0.20 and 2.0 mg?kg^?1) ranged from 81.5% to 107.3% with relative standard deviations (RSDs) in the range of 1.5–13.9% (n = 5) for all analytes. Residue levels of anilinopyrimidine fungicides in fresh and home-processed apple, peach, cabbage and tomato were also studied. The results indicate that residue levels are significantly reduced following washing, peeling and boiling, and there is no toxic metabolite of mepanipyrim (M31) which is detected during boiling. This study provides a theoretical basis for China to draw up maximum residue limits (MRLs) and protect consumers from the negative health effects of pesticide residues detected in fruit and vegetables.     

Field incurred chlorpyrifos and 3,5,6-trichloro-2-pyridinol residues in fresh and processed vegetables

The effect of washing, peeling and cooking on residue levels of chlorpyrifos and 3,5,6-trichloro-2-pyridinol (TCP) in winter (spinach, cauliflower, potato) and summer vegetables (eggplant, tomato, okra) was determined. Analysis was carried out by capillary gas chromatography (DB-5MS capillary column) with mass selective detection. The samples were collected from trials conducted under controlled conditions as well as from the farmer’s field. In supervised field trials, the highest chlorpyrifos residue was found at raw stage in spinach (1.87 mg kg⁻¹) followed by okra (1.41 mg kg⁻¹) and eggplant (1.25 mg kg⁻¹). The lowest residue of chlorpyrifos was recorded in cauliflower (0.036 mg kg⁻¹). The chlorpyrifos residue reduced from 15 to 33% after washing, 65–85% post-peeling and cooking further lowered it from 12% to 48% in all the tested vegetables; while an increase in TCP concentration was observed during heat treatment. Out of 267 vegetable samples collected from the farmer’s field, 225 samples contained detectable residues representing 84% rate of contamination. About 6% of samples contained chlorpyrifos residues above maximum residue limits (MRLs). However, vegetable processing reduced the chlorpyrifos residue below the MRL.     

Residue contents of captan and procymidone applied on tomatoes grown in greenhouses and their reduction by duration of a pre-harvest interval and post-harvest culinary applications

In this study, controlled applications of captan and procymidone were carried out on tomatoes grown in two different greenhouses at different times. The first group of samples were collected immediately after the application and the second group were collected 14 days later. Additionally, control samples were collected before application. The effects of washing, peeling and predetermined storage period, at 4 °C for 7 and 14 days, on the reduction of residue levels in the plant tissues were investigated in the two groups. A gas chromatographic method using acetone, dichloromethane and petroleum ether as extraction solvents, was used to analyse residual captan and procymidone in tomatoes, with obtained recoveries higher than 83%. Captan and procymidone were determined by gas chromatography-electron capture detection (GC-ECD), using a 5% phenylmethylpolysiloxane-coated fused-silica capillary column.

Results showed that waiting for the recommended pre-harvest intervals, indicated on the prospectuses of both pesticides, lowered the residue levels to within acceptable limits. Culinary applications, such as washing and peeling and refrigeration storage, were also effective in reducing the residue levels.     

Monitoring Ontario-grown apples for pest control chemicals used in their production, 1978-86

Between 1978 and 1986, 305 samples of apples were monitored for the residues of a wide range of pesticides used in their production. Three (1%) contained residues above the maximum residue limits (MRL) permitted under the Canadian Food and Drug Act and regulations; two involved phosalone at 5.9 and 6.2 mg/kg respectively and one involved diphenylamine at 6.7 mg/kg when the MRL was 5.0 mg/kg for both compounds. Low residues of dicofol, endosulfan, phosalone, phosmet, captan, daminozide and diphenylamine were frequently found; however they were well below the MRLs. These residue levels were correlated with survey data on the areas of the apple crop treated with specific pesticides. Residues of carbaryl, diazinon, ethion, azinophosmethyl, parathion, and dithiocarbamate fungicides were found occasionally; all were well below the MRLs and correlated with the pattern of use. No residues of PCB were found to a limit of detection of 0.01 mg/kg.     

Pesticide residues in apples grown under a conventional and integrated pest management system

This paper describes method validation for determination of more than 40 pesticides in apples using a GC technique. Target compounds belonged to the organochlorine, organophosphorus, carbamates, pyrethroids, triazoles, dicarboximides and strobilurins groups, among others. Sample preparation consisted of acetone extraction and subsequent cleanup/concentration by SPE with a polymer-based sorbent. Single quadrupole GC–MS operating in SIM mode and electron impact ionization was used for identification and quantification of the pesticides. Average recoveries for analytes ranged between 70 and 110% at three fortification levels – 0.01, 0.1 and 0.2 mg kg^?1. Relative standard deviations were lower than 20% for all tested compounds. Calculated limits of detection and limits of quantification were below 0.01 mg kg^?1, which were sufficiently low compared to the maximum residue levels (MRLs) established by European legislation. The proposed method was applied for determination of pesticide residue in four selected apple varieties after harvesting. Whole and processed fruits (peel and peeled fruits) were analyzed from different treatment systems: two conventional, one based on integrated pest management (IPM) and two variants based on organic production (controls). Higher levels of pesticide residues were found in apple fruits under conventional conditions. Fenitrothion and chlorpyrifos residues were detected frequently in apple peel at concentrations up to 0.45 and 0.77 mg kg^?1, respectively. The levels found in the whole fruits of the same samples were much lower than in peel and below the respective MRLs (0.5 mg kg^?1 for both pesticides). Measurable residues of triadimenol only, up to 0.05 mg kg^?1, concentrated in the peel, were found in the apples from IPM.     

Pesticide residues in fruits and vegetables in Jordan using liquid chromatography/tandem mass spectrometry

A total of 158 fruit and vegetable samples produced in Jordan were examined for the presence of pesticide residues using the multi-residue analysis technique by Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS) and the QuEchERS extraction method. A total of 73 samples (46%) were free from detectable residues, while 85 samples (54%) contained residues. Among the tested samples, 34 (22%) contained residues above Maximum Residue Levels (MRLs) and 51 (32%) contained residues at or below MRLs. Most of the detected residues were found in sweet pepper, peach and apricot samples. Only watermelon samples were free from detectable residues, while tomato and melon samples exhibited residues below MRLs. Out of the 113 pesticides tested, 22 pesticides were found above the limit of detection, 9 of which (hexaconazole, propargite, propiconazole, myclobutanil, thiamethoxam, thiacloprid, clothianidin, clofentezine and pyridaben) had residues that violate MRLs according to European regulations. A continuous monitoring programme for pesticide residues in Jordanian fruits and vegetables is highly recommended.     

Residues of sulfadiazine and doxycycline in broiler liver and muscle tissue due to cross-contamination of feed

Veterinary drugs, such as antimicrobial compounds, are widely used in poultry and may lead to the presence of residues in matrices of animal origin, such as muscle and liver tissue. In this study, broilers received an experimental feed containing sulfadiazine or doxycycline at cross-contamination levels of 2.5, 5 and 10% of the therapeutic dose in feed. Breast and thigh muscle and liver samples were collected during treatment and depletion period and analysed via liquid chromatography-tandem mass spectrometry (LC-MS/MS). Concentrations reached a plateau phase 3-5 days after the start of experimental feeding. A rapid depletion of residues was noted after withdrawal of the experimental feed. No significant differences in measured concentrations were observed between the various muscle types. Residue concentrations for some experimental groups; the 10% group of sulfadiazine and the 5 and 10% group of doxycycline, however, exceeded their corresponding maximum residue limits (MRLs).     

Investigation of pesticide residues in vegetables and fruits grown in various regions of Hatay,Turkey

In this study, 175 pesticide residues in various vegetable and fruit samples grown in different regions of Hatay, Turkey, were investigated. Residue analyses were performed using liquid chromatography–tandem mass spectrometry with the QuEChERS method. In tomato, plum and apricot samples, pesticide residues were below the limits of detection. In other samples, at least one pesticide residue was detected. Twelve pesticides (acetamiprid, carbendazim, chlorpyrifos, fenarimol, fludioxonil, hexythiazox, imidacloprid, metalaxyl, pyridaben, pyriproxyfen, thiabendozole, triadimenol) were found at levels between 0.003 and 0.759?mg?kg^?1. Only in cucumber samples, acetamiprid residues were found at levels greater than the maximum acceptable limit in Turkish Food Codex and European Union maximum residue limits (EU MRLs). In other samples, the detected residue amounts are less than the MRLs declared in the Turkish Food Codex and EU MRLs.     

Relationship between physicochemical properties and maximum residue levels and tolerances of crop-protection products for crops set by the USA, European Union and Codex

Residues on foodstuffs resulting from the use of crop-protection products are a function of many factors, e.g. environmental conditions, dissipation and application rate, some of which are linked to the physicochemical properties of the active ingredients. Residue limits (maximum residue levels (MRLs) and tolerances) of fungicides, herbicides and insecticides set by different regulatory authorities are compared, and the relationship between physicochemical properties of the active ingredients and residue limits are explored. This was carried out using simple summary statistics and artificial neural networks. US tolerances tended to be higher than European Union MRLs. Generally, fungicides had the highest residue limits followed by insecticides and herbicides. Physicochemical properties (e.g. aromatic proportion, non-carbon proportion and water solubility) and crop type explained up to 50% of the variation in residue limits. This suggests that physicochemical properties of the active ingredients may control important aspects of the processes leading to residues.     

2012—2014年青岛、深圳、大连三口岸282份进口水果和蔬菜中农药残留监测

目的掌握和了解进口水果和蔬菜中农药残留污染状况,为国家制定和完善相关标准和采取相关措施提供科学依据。方法本文采用GB/T 19648—2006《水果和蔬菜中500种农药及相关化学品残留量的测定气相色谱-质谱法》和GB/T 20769—2008《水果和蔬菜中450种农药及相关化学品残留量的测定液相色谱-串联质谱法》分析方法,对2012—2014年从青岛、深圳、大连三个主要水果和蔬菜进口口岸采集的282份水果和蔬菜样品进行了666种农药残留的检测。结果对282份水果和蔬菜样品进行农药残留测定和技术分析:未检出农药残留样品31份,占11.0%;检出农药残留样品251份,占89.0%。共检测出农药52种,频次702次。结合中国、欧盟、日本的农药最大残留限量标准,对获得的数据进行了科学的分析:进口香蕉、榴莲、火龙果、草莓的农药残留水平整体处于安全水平,应加强进口龙眼、樱桃、葡萄中农药残留的检测和监管。结论进口水果和蔬菜的农药残留检出率较高,达到89.0%,但超出中国最大残留限量标准的样品较少,只占1.1%,说明进口水果和蔬菜中农药残留整体处于安全水平。     

Variability in captan residues in apples from a Canadian orchard

Apple trees in an orchard in Quebec, Canada were treated, following label directions, with the fungicide captan (1,2,3,6-tetrahydro-N-(trichloromethylthio)phthalimide) during the 2003 agricultural season. A total of 142 apples from three rows of trees were selected for determination of captan by GC/MS. Individual apples were found to contain captan levels ranging from 16.9 to 6350 ng g^-1. Only two individual apple samples exceeded the Canadian maximum residue limit (5000 ng g^-1) for captan in apples. Six composite samples, comprising half portions of eight individual apples, were analysed from each of the three experimental rows. Composite samples ranged in concentration from 166 to 2620 ng g^-1. The greatest uncertainty associated with the measured concentrations was due to variability among apples rather than the measurement of residue levels.     

Canadian Total Diet Study in 1998: pesticide levels in foods from Whitehorse, Yukon, Canada, and corresponding dietary intake estimates.

The Canadian Total Diet Study is a national survey to determine the level of chemical contaminants in the Canadian food supply. Food samples were collected from Whitehorse, Yukon, supermarkets as part of the study in 1998. Whitehorse was chosen as a sampling centre, despite its small population (n = 19,000), to determine if residue levels were different in foods available in northern communities relative to levels observed in previous studies in the more populated south. Foods were prepared as for consumption before pesticide residue analysis. Residue levels observed in most foods were similar to levels observed in samples from previous surveys from southern Canadian cities. Malathion and DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), a transformation product of DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl(ethane), were the two most frequently detected compounds (26.4 and 25.8%, respectively). The majority of pesticides, however, had a detection frequency of < 5%. In general, pesticides in food composites were well below maximum residue limits established in the Canadian Food and Drug Regulations. Chlorpropham and captan had the highest dietary intakes (2.16 and 1.94 micrograms (kg body weight-day)-1, respectively), based on the results from Whitehorse. No dietary intakes above the acceptable daily intakes, however, were observed for any of the 39 pesticides investigated in any age-sex category, where an acceptable daily intake has been proposed.     

Multi-residue analysis of captan,captafol, folpet,and iprodione in cereals using liquid chromatography with tandem mass spectrometry

ABSTRACT

In this study, we propose an improved analytical method for the multiresidue analysis of captan (plus its metabolite, tetrahydrophthalimide), folpet (plus its metabolite, phthalimide), captafol, and iprodione in cereals using liquid chromatography tandem mass spectrometry (LC-MS/MS). As captan, captafol, and folpet are easily degraded during homogenisation and extraction, samples were comminuted with liquid nitrogen, and both QuEChERS and ethyl acetate-based extraction workflows provided a satisfactory method performance. The optimised LC-MS/MS procedure with electrospray ionisation did not degrade these compounds, and offered sufficient method selectivity by resolving and minimising co-eluting matrix-derived interferences. The method also resolved the problem of non-specific mass spectra that these compounds usually produce on GC-MS analysis involving electron ionisation. The method performance was satisfactory for all 6 compounds at 0.01 mg kg^?1 and higher levels of fortification, and validated as per the SANTE/11813/2017 guidelines of analytical quality control in a wide range of cereals including rice, wheat, sorghum, and corn. The method provides special advantage of simultaneous analysis of captan, and folpet along with their metabolites (tetrahydrophthalimide, and phthalimide, respectively) in combination with captafol, and iprodione in a single chromatographic run. Although iprodione is known to degrade to 3,5-dichloroaniline, since this metabolite is not a part of the residue definition, it was not included in the scope of this method. As the method demonstrates satisfactory selectivity, sensitivity, accuracy, precision, and robustness in a wide range of cereal matrices, it is recommended for regulatory testing of these compounds in cereals.     

Efficiency of some technological processes on reducing the residues of malathion and pirimiphos methyl in mature broad bean seeds

Residue study was performed on several insecticides which could contaminate local Egyptian beans. The effect of storage periods and various processing steps on lowering the residues of malathion and pirimiphos methyl in treated seeds and their processed products were investigated. The data indicated that malathion and pirimiphos methyl persisted for more than 90 days on and in stored mature dry broad beans after postharvest treatment. However, stored broad beans could be safely used for human consumption after 90 days when the insecticide residues reached safe levels. Washing removed 69 and 75% of malathion and pirimiphos methyl residues of treated broad beans, respectively. Malathion residue was not detected in various processed products. More than 89 and 99% of malathion residues were absent in dehulled and heated dehulled broad beans. In addition, pirimiphos methyl residues were reduced to 92, 97, 87, 99, 99, and 95% from the initial levels in treated beans following dehulling, cooking of dehulled beans, germination, cooking of germinated beans and cooking of the beans by the common method and under pressure, respectively.     

Pesticide residues in grapes and wine in Italy

Two hundred and one pesticides comprising 84 fungicides, 88 insecticides and 29 herbicides are registered in Italy for use on grapes. Recently, the maximum residue limits (MRLs) for 16 fungicides and five insecticides were established for wine. However, literature data show that some MRLs for wine are not consistent with the corresponding values for grapes. In Italy, the Ministry of Health has the responsibility for checking pesticide contamination in fruit and vegetables in general distribution (i.e. grocery shops, food stores). From 1996 to 1999, out of 1532 grape samples analysed, levels of 1.0, 0.9, 1.8 and 1.9% in each year respectively were contaminated. As part of the National Residue Monitoring Programme, the Ministry of Agriculture carried out investigations of samples collected directly from the field (therefore of a known pesticide treatment history) in order to find the causes of the observed irregularities and to identify preventative measures. In 1996, 1998 and 1999, out of 481, 1195 and 1949 grape samples analysed, 7.9, 6.5 and 2.5% respectively were contaminated, while no residues were detected in 259 wine samples. The National Observatory on Pesticide Residues collects data from analyses performed by highly reliable, non-institutional laboratories on samples from farming cooperatives or individual farms, food companies, wholesale and retail markets. Of the 846 grapes samples and 190 wine samples collected in 1998 and 1999, a total of 6.1 and 2.1% respectively of grapes and 0% for all wine samples were found to contain residues.     

Degradation of organophosphorus pesticides in wheat during cookie processing

For investigating carryover of some organophosphorus pesticide residues in the cereal food chain from grain to consumer, a study was set up on wheat bran, flour and cookies, with and without bran. Special emphasis was given to malathion and chlorpyrifos-methyl residues in cookies for better protection of consumers. Pesticide-free wheat was placed in a small-scale model of a commercial storage vessel and treated with these pesticides. The residue levels of insecticides were determined in wheat, as well as in bran, flour and cookies produced from stored wheat at various time intervals during storage. A multiresidue analysis was performed using GC–NPD and GC–MS. Malathion and chlorpyrifos-methyl residue levels were higher than the maximum residue limits (MRLs) in wheat after 240 days of storage. MRLs established by the EC for malathion and chlorpyrifos-methyl in wheat are 8 and 3 mg kg⁻¹, respectively. The residue levels of insecticides in flour samples also exceeded the MRL (2 mg kg⁻¹ for both insecticides). Eight months of storage were not effective for reducing the residues in wheat to the levels below MRLs. Although, considerable amounts of the insecticides remained in the bran and flour, the cookie processing significantly reduced the concentrations in general. Chlorpyrifos-methyl was more persistent than was malathion and comparatively less degradation occurred during milling and cookie processing due to its physicochemical properties.     

Nutritional comparison of fresh,frozen, and canned fruits and vegetables II. Vitamin A and carotenoids,vitamin E,minerals and fiber

In this second part of our review, we examine the literature for changes in carotenoids, vitamin E, minerals, and fiber due to processing, storage, and cooking of fresh, frozen, and canned fruits and vegetables. While inconsistencies in methodology and reporting methods complicate interpretation of the data, the results show that these nutrients are generally similar in comparable fresh and processed products. The higher levels of carotenoids typically found in canned as compared to fresh products may be attributed to either reporting results on a wet rather than dry weight basis, greater extractability, or differences in cultivars. There are relatively few studies on processing, storage, and cooking effects on vitamin E in fruits and vegetables. Further research is needed to understand nutritional changes in those few fruits and vegetables rich in vitamin E, such as tomatoes. Minerals and fiber are generally stable to processing, storage, and cooking, but may be lost in peeling and other removal steps during processing. Mineral uptake (e.g., calcium) or addition (e.g., sodium) during processing can change the natural mineral composition of a product. Sodium concerns in canned food can be addressed by choosing products with no salt added. Since nutrient content varies considerably by commodity, cultivar, and postharvest treatments, inclusion of a wide variety of fruits and vegetables in the diet is encouraged. Copyright © 2007 Society of Chemical Industry     

Determination of residues of trichlorfon and dimethoate on guava using HPLC

A supervised trial was conducted in guava orchards during 2001 and 2002 to study residue dissipation rates of two organophos insecticides, trichlorfon and dimethoate at Kohat, NWFP, Pakistan. The insecticides were sprayed at recommended doses of 80 and 120 g a.i./100 l water on the fruits of guava when the fruits were semi ripe. The treated guava fruits were randomly sampled in triplicates (2 kg per field replicate) at 0, 3, 7, 14, and 21 days intervals after insecticide application. The samples were extracted in ethyl acetate and were cleaned up through Florisil column with ethyl acetate as eluent. The cleaned up extracts were analyzed for residues by HPLC method. The residues were found to have half-lives of 2.8–3.3 days for dimethoate and 1.7–2.0 days for trichlorfon. Based on the dissipation pattern of the insecticide residues in relation to their respective prescribed maximum residue limits, withholding periods of 3 and 9 days are suggested for guava after treatment with dimethoate and trichlorfon.     

原料预处理对柿子酒发酵过程中理化指标及甲醇和高级醇的影响

以柿子为主要原料,探究原料预处理（去皮、蒸煮）对柿子酒发酵过程中还原糖、总酸、酒精度、甲醇和高级醇的影响。结果表明,原料预处理对柿子酒的酒精度没有显著影响;和带皮处理相比,原料去皮处理酿造的柿子酒中还原糖含量高44%,总酸含量低7.9%,甲醇低19%,高级醇高66%;与不蒸煮处理相比,蒸煮处理酿造的柿子酒中还原糖含量高36%,总酸含量低9.5%,甲醇含量低30%,高级醇含量低48%。因此,对柿子原料进行去皮和蒸煮的处理后酿制柿子酒综合指标较好。