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1.
Environ Monit Assess ; 192(11): 692, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33037524

RESUMO

Residue levels of seven commonly used pesticides were determined in random samples of tomatoes, French beans, and kale collected from horticultural farms in Buuri, Imenti North, and Imenti South sub-counties in Meru, Kenya, just before delivery to the consumers. QuEChERS method for extraction followed by LC-MS/MS was used to determine the concentrations. The concentrations (µg kg-1 wet weight) in French beans, kale, and tomatoes ranged from below detection limit (BDL): BDL-48.65 (carbendazim), BDL-290.76 (imidacloprid), BDL-2.81 (acetamiprid), BDL-25.76 (azoxystrobin), BDL-105.18 (metalaxyl), BDL-0.15 (diazinon), and BDL-0.17(chlorpyrifos). The maximum residue levels determined in the horticultural produce from the three regions were 290 µg kg-1 for imidacloprid in tomatoes from Buuri and 25.76 µg kg-1for azoxystrobin in French beans from Imenti South. The pesticide residue levels generally were extremely low and met the MRLs set by EU and other countries, except for carbendazim and metalaxyl in French beans, and posed no concern to human health. The estimated daily intakes (EDI) (mg kg-1 BW/day) for the population of Meru County were very low ranging from 1.685 × 10-8 (acetamiprid) to 2.381 × 10-5 (imidacloprid) in tomatoes, 2.849 × 10-9 (metalaxyl) to 3.633 × 10-7 (azoxystrobin) in French beans, and 1.392 × 10-8 (diazinon) in kale, respectively. The health risk indices were subsequently extremely low for the detectable pesticide residues, ranging from 6.74 × 10-7 (acetamiprid) to 3.97 × 10-4 (imidacloprid) in tomatoes, 3.56 × 10-8 (metalaxyl) to 5.52 × 10-5 (chlorpyrifos) in French beans, and 6.96 × 10-5 (diazinon) in kale, respectively, indicating no health risk in the population, but their presence in these vegetables cannot be ignored as long-term exposure can still cause health risks.


Assuntos
Brassica , Lycopersicon esculentum , Resíduos de Praguicidas , Praguicidas , Cromatografia Líquida , Monitoramento Ambiental , Contaminação de Alimentos/análise , Humanos , Quênia , Resíduos de Praguicidas/análise , Praguicidas/análise , Espectrometria de Massas em Tandem
2.
Wei Sheng Yan Jiu ; 49(5): 815-822, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33070829

RESUMO

OBJECTIVE: The screening method was established for pesticide residues in substitutional teas such as orange peel, lotus leaf, pueraria lobata and Pangdahai using data base. The method for analyzing of 26 pesticide residues was confirmed in four substitutional teas with gas chromatography-tandem mass spectrometry(GC-MS/MS) and dispersive solid-phase extraction(d-SPE) for sample preparation. METHODS: The 26 types of pesticides were selected as target compounds, including screened out, commonly used in substitutional tea planting and forbidden in agriculture planting. The samples extracted with acetonitrile, and purified by adsorbent(e. g PSA, GCB, C_(18)), the purification solutions were separated on DB-5 MS UI column((15 m+PUU+15 m)×0. 25 mm×0. 25 µm) with programmed temperature and determined by GC-MS/MS in multi-reaction monitoring(MRM) model. The external standard method was applied to quantify the pesticides. RESULTS: The method showed a good linearity(r≥0. 995)in concentration range(2-100 µg/L) for 26 kinds of pesticides. The limits of quantification(LOQ) were 3-40 µg/kg. The average recoveries range were 71. 9%-114. 4% in three add levels of 10, 50, 200 µg/kg, and relative standard deviations of 1. 0%-16. 0%(n=6). In the four matrixes, the pesticides were detected concentrating on orange peel, and there were kinds of residues. CONCLUSION: This method is simple, fast, sensitive, selective and can satisfy the request of pesticide screening and simultaneous analysis of multiple pesticide residues in orange peel, lotus leaf, pueraria lobata and Pangdahai.


Assuntos
Citrus sinensis , Lotus , Resíduos de Praguicidas , Pueraria , Medicamentos de Ervas Chinesas , Cromatografia Gasosa-Espectrometria de Massas , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem , Chá
3.
Environ Monit Assess ; 192(9): 615, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32876774

RESUMO

Pesticides are not only used on food but also on non-food crops, such as tobacco, to control a range of unwanted animal, plant, and microbial, fungal pests. The residue levels in tobacco leaves are expected to decline up to harvest, during drying, and when the leaves are further processed. Additional pesticides may also be applied to the finished product and residue levels may remain present even when the tobacco is burned. Human exposure to pesticide residues on tobacco occurs when residues remaining in cigarette smoke are inhaled. Based on this assumption, the objectives of this research were (i) to determine the level of pesticides residues in harvested tobacco leaves and (ii) to assess the risk of human exposure to these residues in tobacco smoke. Pesticide residues were detected in all analysed tobacco samples. These detected residues represent ten different active ingredients (AI), three of these AIs (thiodicarb, alachlor, and endosulfan) are no longer allowed in Europe. A 54.7% of these residues were quantifiable. Furthermore, it was found that with the use of solid-phase extraction sorbent (SPE) as adsorbent and n-hexane as solvent, higher recoveries of the pesticide residues in the tobacco smoke from the amount spiked can be obtained. It was also found that cigarette filters help to reduce the intake of residues of pesticides that may be present in cigarettes. Finally, the study concluded that both active smoking and passive smoking populations are exposed to pesticide residues in the tobacco smoke.


Assuntos
Resíduos de Praguicidas/análise , Praguicidas/análise , Poluição por Fumaça de Tabaco , Monitoramento Ambiental , Europa (Continente) , Humanos , Medição de Risco , Fumaça/análise , Tabaco
4.
Ecotoxicol Environ Saf ; 205: 111331, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32977287

RESUMO

In China, many studies have been carried out on pesticide residues in human milk, yet all of them are on organochlorine pesticides (OCPs) and mostly focused on large, economically developed cities. In this study, 27 pesticides including OCPs, pyrethroid pesticides (PYRs) and organophosphate pesticides (OPPs) in human milk were investigated in Jinhua, an inland and medium sized city in China. Method based on QuEChERS extraction and gas chromatography-mass spectrometer (GC-MS) determination was adopted to analyze the above pesticide residues. The influencing factors as well as the health risks were also evaluated. Results show that PYRs and OPPs in human milk samples were both undetectable. Regarding OCPs, the detection rate of hexachlorobenzene (HCB), ß-hexachlorocyclohexane (ß-HCH) and p,p'-dichlorodiphenyl-dichloroethylene (p,p'-DDE) were 83.6%, 36.4% and 58.2%, respectively, and their mean value were 29.4, 32.0 and 85.2 ng/g lipid, respectively. p,p'-DDE levels in human milk was significantly (p < 0.05) related to maternal age, but no association was detected between OCPs residues and other factors (living environment, dietary habit, living style, etc.), suggesting that OCPs in human milk in Jinhua were originated from nonspecific source. All estimated daily intake of pesticides (EDIpesticides) by infants were under the guideline suggested by Food and Agriculture Organization (FAO) and China Ministry of Health (CMH). Yet 9% of EDIsHCB and 16% of EDIsHCHs exceeded the guideline recommended by Health Canada. The associations between DDE residues and the delivery way as well as HCBs residues and the birth weight were seemly significant, yet the significance disappeared when consider age or gestational age as a cofounder, indicating that OCPs residue in mother's body in Jinhua has no obvious influence on fetus development and the delivery way.


Assuntos
Hidrocarbonetos Clorados/análise , Leite Humano/química , Organofosfatos/análise , Resíduos de Praguicidas/análise , Adulto , China , Cidades , Diclorodifenil Dicloroetileno/análise , Feminino , Hexaclorobenzeno/análise , Hexaclorocicloexano/análise , Humanos , Lactente , Inseticidas/análise , Idade Materna , Medição de Risco
5.
Ecotoxicol Environ Saf ; 203: 111023, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888592

RESUMO

Tembotrione is a triketone group herbicide having worldwide applications for weed management in maize. It is considered to be less stable in the environment and its degradation products may have toxicological consequences due to longer persistence and off-site movements. We studied the persistence behavior and leaching potential of tembotrione and its major metabolite TCMBA in clay loam and sandy loam soils having different physico-chemical properties. The rapid transformation of parent tembotrione to degradation products and their high interactions with soil provided challenging task of residues separation from complex soil matrix. Therefore, a novel sample preparation method (modified QuEChERS) was optimized for trace estimation of tembotrione and TCMBA which offered 86.6-95.6% recoveries with limit of detection (LOD) and quantification (LOQ) as 0.001 and 0.003 µg/g, respectively in both soils without any matrix interference. A first order dissipation kinetics was followed by tembotrione and TCMBA residues with half-life ranged from 7.2 to 13.4 days in both soils. Residues reached below detectable limit on 45-60 days after treatments in two application doses. Leaching experiment revealed maximum retention of tembotrione residues from 15 to 25 cm depth in both soils whereas TCMBA show appreciable leaching potential. It was concluded that tembotrione can be phytotoxic to the succeeding crops if applied at late post-emergence stage. TCMBA can contaminate surface and ground water due to continuous and prolonged use of tembotrione particularly in light textured soils.


Assuntos
Benzoatos/análise , Cicloexanonas/análise , Herbicidas/análise , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Solo/química , Sulfonas/análise , Argila/química , Produtos Agrícolas/crescimento & desenvolvimento , Cinética , Limite de Detecção , Zea mays/crescimento & desenvolvimento
6.
Bull Environ Contam Toxicol ; 105(4): 602-606, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32978647

RESUMO

A method for simultaneous quantitation of rimsulfuron, quizalofop-P-ethyl and quizalofop-P in potato plant, soil and potato tuber samples was established. The mean recoveries of rimsulfuron, quizalofop-P-ethyl and quizalofop-P in different matrices spiked with them were 81.4%-101.1%, 76.1%-99.0% and 77.4%-106.4% with relative standard deviations (RSDs) of 2.7%-13.3%, 0.9%-5.5%, 1.7%-11.3%, respectively. The open-field trials in China were conducted in potato cultivation system of Changchun and Jinan. The results indicated that the half-lives of rimsulfuron and quizalofop-P-ethyl were 0.04-13.1 days. The residues of quizalofop-P during the harvest time in Jinan soil were < 0.01-0.044 mg kg-1, while there was no residue of target herbicides detected in all other samples. The risk assessment results demonstrated that the risk quotients (RQs) of rimsulfuron and quizalofop-P-ethyl were 7.857 × 10-5 and 8.730 × 10-3, respectively, which exhibited an acceptable dietary risk to Chinese consumers.


Assuntos
Resíduos de Praguicidas/análise , Propionatos/análise , Piridinas/análise , Quinoxalinas/análise , Poluentes do Solo/análise , Sulfonamidas/análise , China , Herbicidas/análise , Medição de Risco , Solo/química , Solanum tuberosum
7.
Environ Monit Assess ; 192(9): 567, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32767114

RESUMO

Rapid industrialization and urbanization have led to severe pollution into water resources which limits to reach safe drinking and irrigation water globally. One of the most important pollutants of environment that brought along with industrialization and technology are pesticides. In this study, it was aimed to investigate the pesticide residues in Dim Stream, due to intense touristic and agricultural activities in the region. Thus, four locations alongside the river were selected for sampling to evaluate the pesticide residue in the stream. The water samples were collected representing the rainy and dry seasons and extracted according to the Quechers method which is validated in terms of accuracy, specificity, limit of detection (LOD), and quantification (LOQ). Pesticide residues were analyzed by injecting LC-MSMS and GC-MS. The most recurrent pesticides were cypermethrin, endosulfan, deltamethrin, dicofol, metribuzin, parathion-methyl, permethrin, malathion, and tetradifon in the samples. Some of the levels of pesticides detected in water were significantly high compared with guideline values set by the Surface Water Quality Regulation of Turkey, EU, and World Health Organization, and this may be hazardous to aquatic life and human health. The obtained 18 recoveries of pesticides in the samples varied between 70 and 120%. LOD was ranged 19 from 0.23 to 9.67 µg/L. LOQ of 11 of the pesticides were higher than 1 µg/L.


Assuntos
Resíduos de Praguicidas/análise , Praguicidas/análise , Monitoramento Ambiental , Humanos , Rios , Turquia
8.
Ecotoxicol Environ Saf ; 202: 110942, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800224

RESUMO

Spinetoram (XDE-175-J/L), a new spinosyn-based insecticide, is one of the most widely used bio-pesticide worldwide and its registration for direct application on cauliflower to control Plutella xylostella is currently under review in China. In this study, an accredited method for simultaneous determination of spinetoram and its two metabolites in cauliflower was established and validated using QuEChERS (quick, easy, cheap, effective, rugged, and safe) preparation coupled with ultra-liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The average recoveries using this method were ranged from 74 to 99% with relative standard deviations (RSDs) of 2.4-10.5%. The dissipation kinetics and terminal residues of spinetoram and its two metabolites in cauliflower were studied in Tianjin and Guizhou over two years under open field conditions. The dissipation experiments revealed that spinetoram was swiftly degraded in cauliflower, with the half-lives less than or equal to 4.85 days. The terminal residues of total spinetoram (sum of spinetoram and its two metabolites) detected in cauliflower samples were in the range of 0.009 mg/kg-0.337 mg/kg. Dietary risk assessment study was implemented based on the scientific data of field trials, food consumption and acceptable daily intake (ADI). The estimated long-term dietary risk probability (RQ) of total spinetoram from cauliflower was between 5.79% and 5.91%, indicating that spinetoram was associated with acceptable risk for dietary cauliflower consumption. The results would provide scientific guidance for proper usage of spinetoram in cauliflower field ecosystem.


Assuntos
Brassica/fisiologia , Inseticidas/toxicidade , Macrolídeos/toxicidade , China , Cromatografia Líquida/métodos , Dieta , Ecossistema , Inseticidas/análise , Cinética , Resíduos de Praguicidas/análise , Medição de Risco , Espectrometria de Massas em Tandem/métodos
9.
Sci Total Environ ; 745: 141036, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32758732

RESUMO

Pesticide and veterinary drug residues are one of the stress factors affecting bee health and mortality. To investigate the occurrence, the concentration and the toxicity risk to bees of pesticide residues in four different types of beeswax (brood comb wax, recycled comb wax, honey comb wax, and cappings wax), 182 samples were collected from apiaries located all over the Belgian territories, during spring 2016 and analysed by LC-MS/MS and GC-MS/MS for the presence of 294 chemical residues. The toxicity risk to bees expressed as the Hazard Quotient (HQ) was calculated for each wax sample, according to two scenarios with different tau-fluvalinate LD50 values. Residues showing the highest prevalence were correlated to bee mortality in a multivariate logistic regression model and a risk-based model was used to predict colony bee mortality. Altogether, 54 different pesticide and veterinary drug residues were found in the four types of beeswax. The residues with a higher likelihood to be retained in beeswax are applied in-hive or with a high lipophilic nature. The multivariate logistic regression model showed a statistically significant influence of chlorfenvinphos on bee mortality. All our results indicated that cappings wax was substantially less contaminated. This national survey on beeswax contamination provides guidelines on the re-use of beeswax by beekeepers and shows the necessity to introduce maximum residue levels for global trade in beeswax. An online tool was developed to enable beekeepers and wax traders to estimate the risk to honey bee health associated with contaminated wax.


Assuntos
Resíduos de Praguicidas/análise , Resíduos de Praguicidas/toxicidade , Praguicidas/análise , Drogas Veterinárias , Animais , Abelhas , Bélgica , Cromatografia Líquida , Espectrometria de Massas em Tandem , Ceras
10.
J Chromatogr A ; 1627: 461398, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823103

RESUMO

A new mode of dispersive solid phase extraction based on in situ formation of adsorbent in aqueous phase has been introduced as an efficient method for the extraction of some pesticide residues in fruit juice samples. In this method, polycarbonate which is an inexpensive polymer is used as an adsorbent for the first time. The method is followed by dispersive liquid-liquid microextraction for more enrichment of the analytes. In the present study, a proper amount of the polymer is dissolved in N,N-dimethyl formamide and the obtained solution is injected into an aqueous phase containing the analytes. After injection, polycarbonate particles are formed and adsorbed the analytes. Then, the adsorbent is separated from the aqueous solution and eluted by acetone. The obtained acetone phase is mixed with 1,1,1-trichloroethane and the mixture is dispersed into deionized water and a cloudy solution is formed. Ultimately, after centrifugation, the obtained sedimented phase containing the extracted analytes is injected into gas chromatography-flame ionization detection. In the proposed method, the adsorbent synthesis step, which often is a time-consuming, expensive, and laborious step in most adsorbent-based sample preparation methods, has been removed. Moreover, there is no need for sonication or vortex agitation. Under the optimized experimental conditions, the relative standard deviation was equal or less than 7% for intra- (n = 6) and inter-day (n = 5) precisions at a concentration of 50 µg L-1 of each pesticide. The limits of detection and quantification were in the ranges of 0.34-1.2 and 1.1-4.0 µg L-1, respectively. In addition, extraction recoveries and enrichment factors varied in the ranges of 44-89% and 220-443, respectively.


Assuntos
Sucos de Frutas e Vegetais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Centrifugação , Limite de Detecção , Microextração em Fase Líquida/métodos , Resíduos de Praguicidas/isolamento & purificação , Extração em Fase Sólida , Solventes/química , Triazinas/análise , Triazinas/isolamento & purificação , Água/química
11.
Bull Environ Contam Toxicol ; 105(4): 595-601, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32862252

RESUMO

The residual characteristics and risk assessment with respect to cyazofamid and its metabolite 4-chloro-5-p-tolylimidazole-2-carbonitrile were monitored in case of Korean cabbage at different preharvest intervals during a greenhouse trial. The 0.02 kg a.i/ha of cyazofamid was sprayed twice on seven-day intervals (i.e., on day 0, 7, 14, and 21 before harvest). The liquid chromatography-tandem mass spectrometry analysis was used to monitor the residual amount of fungicide. The matrix-matched calibration curves with respect to the cyazofamid in Korean cabbage exhibited good linearity (R2 ≥ 0.999) and acceptable recoveries of 84.1%-114.9%. The biological half-life of cyazofamid in Korean cabbage was 3.18 days. During the treatment, the preharvest residue of cyazofamid in Korean cabbage 14 days before harvest (0.80 mg/kg) was lower than that specified by the MFDS-MRL (Ministry of Food and Drug Safety-Maximum Residue Limit, 2.0 mg/kg) and should be recommended as the safe preharvest-interval application limit. The hazard quotient showed low toxicity (70.58%) during the risk assessment study of cyazofamid.


Assuntos
Fungicidas Industriais/toxicidade , Imidazóis/toxicidade , Resíduos de Praguicidas/toxicidade , Sulfonamidas/toxicidade , Brassica/química , Cromatografia Líquida/métodos , Fungicidas Industriais/química , Fungicidas Industriais/metabolismo , Meia-Vida , Imidazóis/metabolismo , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/metabolismo , República da Coreia , Medição de Risco , Sulfonamidas/metabolismo
12.
J Chromatogr A ; 1627: 461414, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823112

RESUMO

Various techniques have been evaluated for the extraction and cleanup of pesticides from environmental samples. In this work, a Selective Pressurized Liquid Extraction (SPLE) method for pesticides was developed using a Thermo Fisher Scientific Accelerated Solvent Extraction (ASE) system. This instrument was compared to the newly introduced (2017) extraction instrument, the Energized Dispersive Guided Extraction (EDGE) system, which combines Pressurized Liquid Extraction (PLE) and dispersive Solid Phase Extraction (dSPE). We first optimized the SPLE method using the ASE instrument for pesticide extraction from alfalfa leaves using layers of Florisil and graphitized carbon black (GCB) downstream of the leaf homogenate in the extraction cell (Layered ASE method). We then compared results obtained for alfalfa and citrus leaves with the Layered ASE method to those from a method in which the leaf homogenate and sorbents were mixed (Mixed ASE method) and to similar methods modified for use with EDGE (Layered EDGE and Mixed EDGE methods). The ASE and EDGE methods led to clear, colorless extracts with low residual lipid weight. No significant differences in residual lipid masses were observed between the methods. The UV-Vis spectra showed that Florisil removed a significant quantity of the light-absorbing chemicals, but that GCB was required to produce colorless extracts. Recoveries of spiked analytes into leaf homogenates were generally similar among methods, but in several cases, significantly higher recoveries were observed in ASE extracts. Nonetheless, no significant differences were observed among pesticide concentrations in field samples when calculated with the isotope dilution method in which labelled surrogates were added to samples before extraction. The extraction time with the ASE methods was ~45 minutes, which was ~4.5 times longer than with the EDGE methods. The EDGE methods used ~10 mL more solvent than the ASE methods. Based on these results, the EDGE is an acceptable extraction instrument and, for most compounds, the EDGE had a similar extraction efficiency to the ASE methods.


Assuntos
Técnicas de Química Analítica/métodos , Praguicidas/análise , Folhas de Planta/química , Solventes/química , Lipídeos/química , Medicago sativa/química , Resíduos de Praguicidas/análise , Extratos Vegetais/química , Espectrofotometria Ultravioleta
13.
J Chromatogr A ; 1627: 461416, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823114

RESUMO

Animal feeds are often reported to be contaminated with chemical residues, and when present above the maximum legal limit, these compounds can cause harmful effects to consumers of animal produce. Thus, animal feed safety is an important regulatory concern. The aim of this study was to optimise a multiresidue method for the simultaneous analysis of multi-class pesticides and a number of frequently used veterinary drugs using LC-MS/MS and GC-MS/MS. The method was validated in a range of feed matrices, including maize feed, poultry feed and mixed feed concentrate. The optimised sample preparation workflow involved extraction of feeds (5 g) with ethyl acetate (10 mL), followed by a freezing step (at -20°C) used for eliminating the matrix co-extractives. The extract was further cleaned by dispersive solid phase extraction with a combination of primary secondary amine, C18 and florisil sorbents. From the cleaned-extract, an aliquot was analysed by GC-MS/MS, while another portion of it was solvent-exchanged to acetonitrile:water (50:50) and then analysed by LC-MS/MS. This method effectively minimised the matrix interferences. A total of 192 pesticides was analysed by GC-MS/MS within a runtime of 22 min. The LC-MS/MS method was validated for 187 compounds including 17 veterinary drugs. For most of the compounds, the limit of quantification (LOQ) was 0.01 mg/kg. The recoveries at LOQ and higher levels ranged between 70% and 120%, with precision-RSDs of < 20%. The method provided a precise analysis in a wide range of market-feed samples. As shown, the method is suitable for regulatory and commercial testing purposes.


Assuntos
Ração Animal/análise , Cromatografia Líquida/métodos , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Drogas Veterinárias/análise , Animais , Congelamento , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Resíduos de Praguicidas/análise , Reprodutibilidade dos Testes , Solventes/química , Água/química
14.
J Chromatogr A ; 1625: 461226, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709310

RESUMO

In this work, an easy and fast procedure for the selective multiresidue determination of 14 highly polar pesticides (including glyphosate, glufosinate, ethephon and fosetyl) and metabolites in beverages is presented. After an initial sample dilution (1:1, v/v), the extract is shaken and centrifuged, further diluted and then injected directly into the LC-MS/MS system, using hydrophilic interaction liquid chromatography (HILIC) and tandem mass spectrometry. No clean-up procedure was needed. The method was validated according to the current European guidelines for pesticide residue analysis in food and feed and linearity, limits of detection and quantification, matrix effects, trueness and precision were assessed. For plant-based milk, wine and beer samples, 10, 11 and 12 analytes, respectively, out of 14 were fully validated at 10 µg kg-1, the lowest spike level tested. The matrix effect was negative in most of the cases, showing for some compounds, such as HEPA, up to 80% suppression when compared to the response from standards in solvent. The use of isotopically labelled internal standards is required for the optimal quantification, as it compensates for high and varying matrix effects and also for recovery losses during extraction.


Assuntos
Cerveja/análise , Cromatografia Líquida de Alta Pressão/métodos , Substitutos do Leite/química , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Vinho/análise , Animais , Ânions/química , Interações Hidrofóbicas e Hidrofílicas , Leite de Soja/química
15.
Environ Sci Pollut Res Int ; 27(31): 39253-39264, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32642894

RESUMO

Long-term monitoring is essential to assess the patterns and distribution of the residues of organochlorine pesticides (OCPs) in biota. Bird eggs have several advantages than other environmental matrixes, which have been used extensively to portray the accumulation and distribution of OCPs. The present study investigated the organochlorine pesticide (OCP) residues in eggs of 22 species of terrestrial birds collected from Tamil Nadu, India. Eggs found abandoned were collected during nest monitoring between 2001 and 2008 and analyzed for the presence of organochlorine pesticide residues. The results showed that the mean concentrations of total hexachlorohexane (∑HCHs), total dichlorodiphenyltrichloroethane (∑DDTs), heptachlor epoxide, and dieldrin ranged from non-detectable (nd) to 2800 ng/g, nd to1000 ng/g, nd to 700 ng/g, and nd to 240 ng/g on a wet mass (wm) basis, respectively. The variation in magnitude of contamination among the species and feeding guilds were not significantly different (p > 0.05). Among the OCPs analyzed, the residues of ß-HCH and p,p'-DDE were found to be the abundant in concentration. Similarly, among various bird species studied, the highest concentrations of ∑OCPs (> 5000 ng/g wm) were recorded in the eggs of gray junglefowl, scaly-breasted munia, and red-whiskered bulbul. This may be due to their widespread occurrence of their habitat at proximity to the agricultural fields, where organochlorines were in use until recently. Among the various contaminants analyzed, concentrations of p,p'-DDE and heptachlor epoxide exceeded the threshold levels of toxicity for wild birds in > 5% of the egg samples. Hence, this study indicates the need for continued monitoring and further systematic ecotoxicological investigation of these compounds not only in eggs but also in other environmental media.


Assuntos
Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Animais , Aves , Monitoramento Ambiental , Índia
16.
Food Chem ; 331: 127352, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32652343

RESUMO

The influence of some additives, including metal ions, antioxidants, enzyme inhibitors and organic solvents, on the storage stability of four organophosphorus pesticides in cucumber samples were investigated. It was found that metal ions, including Al3+, Fe3+, and Co2+, increased the stability of dichlorvos, malathion, and chlorpyrifos. Conversely, Al3+, Fe3+, Fe2+, and Co2+ caused catalytic degradation of diazinon. With the addition of organic solvents (CH2Cl2, CHCl3, CCl4, CH3OH and CH3COCH3), remaining of diazinon residues was higher (16-54%) after storage for seven days. CCl4 was associated with the highest retention of malathion, diazinon, and chlorpyrifos (33%, 48% and 44%, respectively) in samples. SDS also stabilized the pesticides since residues were, again, higher (13-38%) after seven days storage. Furthermore, addition of Al3+ and Fe3+ decreased peroxidase (POD) activity and inhibited degradation of dichlorvos and malathion. After 14 days, lyophilization increased the pesticide residues remaining by 36%, 29%, and 58% for diazinon, malathion and chlorpyrifos, respectively. Overall, the stability of these pesticides during storage is impacted by water content and addition of exogenous substances. This could ensure higher quality of pesticide residue data in samples.


Assuntos
Cucumis sativus/química , Contaminação de Alimentos/análise , Armazenamento de Alimentos , Inseticidas/química , Compostos Organofosforados/química , Alumínio/química , Clorpirifos/análise , Clorpirifos/química , Diazinon/análise , Diazinon/química , Diclorvós/análise , Diclorvós/química , Aditivos Alimentares/química , Liofilização , Inseticidas/análise , Malation/análise , Malation/química , Compostos Organofosforados/análise , Oxirredutases/química , Peroxidases/química , Peroxidases/metabolismo , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/química , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Dodecilsulfato de Sódio/química , Água/química
17.
Environ Monit Assess ; 192(8): 546, 2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32719898

RESUMO

Seven pesticides, profenofos, metalaxyl, λ-cyhalothrin, 4,4'-DDT, 4,4'-DDE, and α- and ß-endosulfan, were determined in vegetables (tomato, onion) from 20 locations and surface waters from 12 locations in the Central Rift Valley (CRV) of Ethiopia. Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) and solid phase extraction (SPE) methods were used for the vegetables and water, respectively. In 2.5% of the tomato samples, profenofos was detected above European maximum residue limits (MRLs), in 12.5% of the samples metalaxyl, and in 2.5% α- and ß-endosulfan. In 5% of the onion samples, profenofos was detected above European MRLs, in 7.5% of the onion samples metalaxyl, and in 5% λ-cyhalothrin. In surface water, profenofos was detected at the highest concentration of 2300 µg/L in the Bulbula River, 890 µg/L near the agricultural land north of Lake Ziway (ANLZ-1), 1700 µg/L in the floriculture effluent (FE-1), and 900 µg/L in tap water at the Batu Drinking Water (BDW) supply. These results show that the levels of pesticides are in several cases substantially elevated, and emphasize the need of regular pesticide monitoring programs for surface waters and vegetables in the Ethiopian CRV.


Assuntos
Resíduos de Praguicidas/análise , Praguicidas/análise , Monitoramento Ambiental , Etiópia , Contaminação de Alimentos/análise , Verduras
18.
J Environ Sci Health B ; 55(9): 783-793, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32586197

RESUMO

Considering the increase in agricultural production in Tocantins and in the use of pesticides for such production, this work investigates the levels of pesticide residues in different environmental compartments (soil, sediment, and water samples) of the Formoso River in the state of Tocantins, Brazil. The presence of pesticides of the triazine, triazole, and benzimidazole classes was analyzed by UHPLC-MS/MS from April 2018 to February 2019. There were four quarterly collections in the dry and rainy periods. The active principles were not found in sediment samples. In soil samples, only the active ingredients tebuconazole and propiconazole were found in the third collection campaign. The active ingredients amethryn, atrazine, carbendazim, epoxiconazole, metconazole, propiconazole, simazine, tebuconazole, and tetraconazole were found in water samples from Formoso River at concentrations of up to 0.286 µg L-1 (atrazine). Although the substances are in low concentrations, we cannot assume that this toxicity is low considering that the risk of a certain pesticide depends on levels and exposure time. Therefore, the action of substances external to the natural environment always threatens biodiversity.


Assuntos
Benzimidazóis/análise , Praguicidas/análise , Triazinas/análise , Triazóis/análise , Poluentes Químicos da Água/análise , Brasil , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental , Sedimentos Geológicos/análise , Resíduos de Praguicidas/análise , Rios/química , Poluentes do Solo/análise , Espectrometria de Massas em Tandem
19.
Environ Sci Pollut Res Int ; 27(26): 32820-32828, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32519101

RESUMO

Azoxystrobin, buprofezin, dinocap and hexaconazole are widely used in crop protection of mango from flowering to harvest. Residue assessment of these chemicals on mango fruits was done following treatments at the recommended and double doses as per good agricultural practices (GAP). Mango fruit and soil sample preparation was done by QuEChERS, and analysis was done using LC-MS/MS (liquid chromatography mass spectrometry). Using these techniques, the limit of detection (LOD) determined was 1.5 µg kg-1 and limit of quantification (LOQ) was 0.005 mg kg-1 for all analytes. The residue levels on mango initially were 0.265 and 0.55 mg kg-1 for azoxystrobin, 0.63 and 0.974 mg kg-1 for buprofezin, 0.635 and 0.98 mg kg-1 for dinocap and 0.203 and 0.35 mg kg-1 for hexaconazole from standard and double dose treatments, respectively. The dissipation rate of the pesticides on mango fruits was about the same except for azoxystrobin, which dissipated slowly compared with others. The half-life of degradation (DT50) of azoxystrobin was 10.4-12.1 days; buprofezin, 5.8-8.5 days; dinocap, 5.4-6.2 days; and hexaconazole, 4.4-6.1 days. The pre-harvest interval (PHI) based on European Union (EU) MRL (maximum residue limit) requirements were 1 day for azoxystrobin, 15 and 26 days for buprofezin, 27 and 34 days for dinocap, and 19 and 30 days for hexaconazole. The results of this study can be used to produce mango fruits safe for consumption and to meet the regulatory requirements for export of mango fruits from India.


Assuntos
Mangifera , Resíduos de Praguicidas/análise , Cromatografia Líquida , Dinitrobenzenos , Monitoramento Ambiental , Frutas/química , Índia , Pirimidinas , Estrobilurinas , Espectrometria de Massas em Tandem , Tiadiazinas , Triazóis
20.
J Environ Sci Health B ; 55(8): 712-718, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32515641

RESUMO

The degradation under field conditions and the residue behavior of etoxazole during juicing and purée making was evaluated. Etoxazole residues were determined by HPLC-UV at six different Pre Harvest Intervals (PHIs) as to estimate the degradation of residue in fruits. Samples with significant residues were processed and residue were determined after juicing and purée making. The effect of washing was also estimated. Processing Factors (PFs) for etoxazole after each step were less than 1 and the PFs of the overall processes were lower than 0.85 for washing fruits, 0.13 for juice and 0.04 for purée. The studied processes could obviously reduce the pesticide residues that are present in the raw strawberries. Uncertainties in the use of the PFs were identified due to the potential formation of metabolites during the processes.


Assuntos
Contaminação de Alimentos/análise , Indústria de Processamento de Alimentos/métodos , Fragaria/química , Oxazóis/análise , Cromatografia Líquida de Alta Pressão , Egito , Frutas/química , Resíduos de Praguicidas/análise
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