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1.
Pharmacol Res ; 208: 107388, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39243915

RESUMO

Scientific risk assessment of exogenous and endogenous toxic substances in traditional Chinese medicine (TCM) is of great significance. The present review comprises a comprehensive summary of progress in the health risk assessment of harmful exogenous substances in TCMs. Such substances include heavy metals, pesticide residues, biotoxins, and endogenous toxic components involving pyrrolizidine alkaloids. The review also discusses the strengths and weaknesses of various bioaccessibility and bioavailability models, and their applications in risk assessment. Future avenues of risk assessment research are highlighted, including further exploration of risk assessment parameters, innovation of bioaccessibility and bioavailability techniques, enhancement of probabilistic risk assessment combined with bioavailability, improvement of cumulative risk assessment strategies, and formulation of strategies for reducing relative bioavailability (RBA) values in TCMs. Such efforts represent an attempt to develop a risk assessment system that is capable of evaluating the exogenous and endogenous toxic substances in TCMs to ensure its safe use in clinics, and to promote the sustainable development of the TCM industry.


Assuntos
Disponibilidade Biológica , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Medição de Risco , Humanos , Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/toxicidade , Medicamentos de Ervas Chinesas/efeitos adversos , Animais , Resíduos de Praguicidas/farmacocinética , Resíduos de Praguicidas/toxicidade , Resíduos de Praguicidas/análise , Metais Pesados
2.
Regul Toxicol Pharmacol ; 127: 105049, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34619289

RESUMO

Pesticide residues in crop plants are routinely measured in an edible commodity or in feed items to determine safe use. Pesticides present as dislodgeable foliar residues (DFR) are measured for use in non-dietary risk assessments where worker, resident and bystander re-entry may lead to contact with the treated foliage. Possible correlations between dietary and DFR residue decline have been investigated considering data from 177 dietary residue trials along with 56 DFR trials from outdoor studies on the same crops besides residue decline data available in the Plant Properties Database (PPDB).The residue studies proved to follow the non-normal distribution and the comparison between DT50 of both types of residues for all the active substances revealed higher numerical DT50 mean values of the dietary residue compared to the DFRs. The dissipation from dietary residue studies is slower with a higher population mean compared to the mean for DFR studies for most active substances studied. A DT50 value from dietary residue studies could potentially act as a conservative surrogate DT50 for DFR which could be useful in determining the length of DFR studies and benefit both the agrochemical industry and the regulatory bodies in supporting non-dietary pesticide risk assessment.


Assuntos
Agroquímicos/análise , Dieta , Exposição Ambiental/análise , Resíduos de Praguicidas/análise , Agroquímicos/farmacocinética , Meia-Vida , Exposição Ocupacional/análise , Resíduos de Praguicidas/farmacocinética , Medição de Risco
3.
Biomed Chromatogr ; 35(12): e5213, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34227143

RESUMO

Cyantraniliprole is an anthranilic diamide insecticide used for the effective management of diamondback moth in cabbage. Dietary risk assessment of pesticides in food is a major concern now. This study developed a QuEChERS/HPLC-PDA-based highly efficient and reliable method, registering 89.80-100.11% recoveries of cyantraniliprole and its metabolite IN-J9Z38 from cabbage and soil with a relative standard deviation of 0.43-5.77%. Field experiment was conducted to study the residue dissipation of cyantraniliprole in cabbage and soil. Two foliar treatments of 10.26% formulation (Benevia) at 60 (T1 ) and 120 (T2 ) gram active ingredient/hectare were applied. The dissipation half-lives of cyantraniliprole in cabbage and soil were determined to be 3.5-4.2 and 3.8-5.3 days at T1 and 3.9-4.8 and 4.1-4.7 days at T2 , respectively. The maximum concentrations of IN-J9Z38 at T1 and T2 were 0.819 and 1.061 mg/kg, respectively, on the fifth day. A risk quotient value of <1 indicates no dietary risk to the consumers. The residues in the harvested cabbage were below the tolerance level of 2.0 mg/kg established by the regulatory body in India.


Assuntos
Brassica/química , Inseticidas , Resíduos de Praguicidas , Pirazóis , Poluentes do Solo , ortoaminobenzoatos , Brassica/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Dieta , Humanos , Inseticidas/análise , Inseticidas/farmacocinética , Inseticidas/toxicidade , Modelos Biológicos , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/farmacocinética , Resíduos de Praguicidas/toxicidade , Pirazóis/análise , Pirazóis/farmacocinética , Pirazóis/toxicidade , Medição de Risco , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética , Poluentes do Solo/toxicidade , ortoaminobenzoatos/análise , ortoaminobenzoatos/farmacocinética , ortoaminobenzoatos/toxicidade
4.
Regul Toxicol Pharmacol ; 124: 104958, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33991633

RESUMO

The nonlinearity of internal exposure to 8 pesticides was investigated in toxicity studies using kinetics to identify nonlinearity visually and to investigate the influence of nonlinearity on toxicological evaluation. Data were obtained from risk assessment reports published by the Food Safety Commission (FSCJ). Nonlinearity was defined using 2 indicators: the lowest visual inflection point (LVIP) and the second lowest visual inflection point (SVIP) of kinetics by drawing a linear distribution chart. The area under the curve and 24-h urine concentrations were stable parameters used to identify the LVIP/SVIP. The sampling timing affected the blood concentrations, and the LVIP/SVIP was detected for 6 pesticides using the parent compounds or their metabolites as analytes. The subproportional nonlinearity was significant for these pesticides. The LVIP/SVIP values were consistent in the same species up to a 1-year period, but the values showed species-specific differences in several compounds. In all compounds found to be nonlinear, apical outcomes were observed at the SVIP or above. The presence of nonlinearity was recognized by the FSCJ. The recognition influenced their judgment of no-observed-adverse-effect levels (NOAELs) for carcinogenicity or health-based guidance values, indicating the importance of appropriate kinetics to identify the nonlinearity for toxicological evaluation of pesticide residue.


Assuntos
Resíduos de Praguicidas/toxicidade , Testes de Toxicidade/normas , Animais , Carcinogênese/induzido quimicamente , Interpretação Estatística de Dados , Cães , Análise de Perigos e Pontos Críticos de Controle/métodos , Japão , Camundongos , Nível de Efeito Adverso não Observado , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/farmacocinética , Resíduos de Praguicidas/normas , Coelhos , Ratos , Especificidade da Espécie , Testes de Toxicidade/estatística & dados numéricos , Toxicocinética
5.
Food Chem ; 342: 128354, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33268165

RESUMO

The present work describes the development of an in silico model to predict the retention time (tR) of a large Compound DataBase (CDB) of pesticides detected in fruits and vegetables. The model utilizes ultrahigh-performance liquid chromatography electrospray ionization quadrupole-Orbitrap (UHPLC/ESI Q-Orbitrap) mass spectrometry (MS) data. The available CDB was properly curated, and the pesticides were represented by conformation-independent molecular descriptors. In an attempt to improve the model predictions, the best four MLR models obtained were subjected to a consensus analysis. The optimal model was evaluated by means of the coefficient of determination and the residual standard deviation in calibration, validation, and prediction, along other internal and external validation criteria to accomplish the guidelines defined by the Organization for Economic Co-operation and Development. Finally, the in silico model was applied to predict the tR of an external set of 57 pesticides.


Assuntos
Cromatografia Líquida de Alta Pressão , Análise de Alimentos/métodos , Frutas/química , Informática , Resíduos de Praguicidas/análise , Espectrometria de Massas por Ionização por Electrospray , Verduras/química , Calibragem , Contaminação de Alimentos/análise , Frutas/metabolismo , Resíduos de Praguicidas/farmacocinética , Verduras/metabolismo
6.
Environ Geochem Health ; 43(5): 1941-1952, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33201396

RESUMO

In this case, the dissipation and residues of imidacloprid as well as its control efficacy against aphids (Aphis gossypii Glover) in cotton cropping system were reported. After the final spray at the rates of 10.5-42.5 g a.i. ha-1, the initial deposits were 0.59-2.25 mg kg-1 with half-lives of 2.12-2.84 days on leaves and 0.06-0.21 mg kg-1 with half-lives of 1.51-4.20 days in soil, respectively. The initial residues were significantly higher with longer persistence in the upper position of the leaf than in middle and lower positions. The different application dosages could induce a significant difference in the initial deposits, but not show consistent correlation with the dissipation rate. The repeated applications of imidacloprid could alter its residue levels and dissipation rates. The long-term residue concentrations of imidacloprid (60 days after the final application) reached to the nondetectable level in soil. Combined with the control efficacy results, it was considered that the recommended dose of imidacloprid on cotton could be used effectively and safe in this arid area from the view of crop protection and environmental contamination.


Assuntos
Afídeos/efeitos dos fármacos , Gossypium/efeitos dos fármacos , Inseticidas/farmacologia , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Animais , Biodegradação Ambiental , China , Meia-Vida , Controle de Insetos/métodos , Inseticidas/análise , Inseticidas/farmacocinética , Neonicotinoides/análise , Neonicotinoides/farmacocinética , Nitrocompostos/análise , Nitrocompostos/farmacocinética , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/farmacocinética , Folhas de Planta/efeitos dos fármacos , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética
7.
Food Funct ; 11(7): 6028-6037, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32697245

RESUMO

For most people, the pesticide residues found on agriculture products are the main source of pesticide exposure, which may adversely influence consumer health. The potential health hazard of residual pesticides depends on the nature of the foods they are consumed with. Studies with fat-soluble vitamins and nutraceuticals have shown that their bioaccessibility depends on food matrix composition and structure. We used an in vitro method to investigate the influence of the dimensions of the lipid phase in model fatty foods (emulsified or bulk oil) on the bioaccessibility of various pesticides. Three pesticides that differed in their oil-water partition coefficients were selected: bendiocarb (log P = 1.7), parathion (log P = 3.8), and chlorpyrifos (log P = 5.3). These pesticides were mixed with tomato puree to represent pesticide-treated agricultural products. Three model foods with different oil phase dimensions were used to represent different kinds of food product: small emulsions (d32 = 0.14 µm); large emulsions (d32 = 10 µm); and, bulk oil. Our results showed that the oil droplets underwent extensive changes as they passed through the simulated gastrointestinal tract due to changes in environmental conditions, such as pH, ionic strength, bile salts, and enzyme activities. The initial rate and final amount of lipid hydrolysis decreased with increasing lipid phase dimensions. Pesticide bioaccessibility depended on both the hydrophobicity of the pesticide and the dimensions of the co-ingested lipid droplets. The least hydrophobic pesticide (bendiocarb) had a high bioaccessibility (>95%) that did not depend on lipid phase dimensions. The more hydrophobic pesticides (parathion and chlorpyrifos) has a lower bioaccessibility that increased with decreasing lipid phase dimensions. Our results demonstrate the critical role that food structure plays on the potential uptake of pesticides from agricultural products, like fruits and vegetables.


Assuntos
Clorpirifos/análise , Clorpirifos/farmacocinética , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/farmacocinética , Praguicidas/análise , Praguicidas/farmacocinética , Disponibilidade Biológica , Clorpirifos/toxicidade , Produtos Agrícolas/química , Suplementos Nutricionais , Digestão , Emulsões/química , Frutas , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Concentração de Íons de Hidrogênio , Solanum lycopersicum/química , Tamanho da Partícula , Resíduos de Praguicidas/toxicidade , Praguicidas/toxicidade , Verduras
8.
J Environ Sci Health B ; 55(7): 613-619, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32308122

RESUMO

Field trials in six agricultural sites were carried out to investigate the dissipation and residue levels of pyridaben in kiwifruit. Each sample was extracted with acetonitrile, purified with octadecylsilane and analyzed with high-performance liquid chromatography-tandem mass spectrometry. The method had good linearity (R2 > 0.99), accuracy (recoveries of 78.53-98.00%) and precision (relative standard deviation of 0.86-6.11%). The dissipation of pyrdaben in kiwifruit followed first-order kinetics with a half-life < 8 d, and terminal residues in kiwifruit were lower than 0.5 mg/kg after 14 d of application. Risk assessment indicated that both chronic and acute dietary intake risk values were far below 100%, suggesting that pyridaben residues in kiwifruit were relatively safe to humans. Moreover, the effects of traditional household processes on kiwifruit were investigated. The processing factors (PFs) indicated that peeling and peeling-juicing processes could remove pyridaben residues from kiwifruit, and the former was more effective than the latter (PF at 0.15 vs. 0.51). Nevertheless, drying kiwifruit with an oven increased the amount of pyridaben (PF at 1.05). These results could provide guidance for the safe and reasonable use of pyridaben in agriculture and may be helpful for the Chinese government to determine maximum residue limit of pyridaben in kiwifruit.


Assuntos
Actinidia/química , Piridazinas/análise , Piridazinas/farmacocinética , Agricultura , China , Cromatografia Líquida de Alta Pressão , Culinária , Exposição Dietética/efeitos adversos , Contaminação de Alimentos/análise , Frutas/química , Meia-Vida , Humanos , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/farmacocinética , Medição de Risco
9.
Int J Hyg Environ Health ; 228: 113526, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32305862

RESUMO

BACKGROUND: Since the classification of glyphosate as a Group 2A substance "probably carcinogenic to humans" by the IARC in 2015, human health concerns have been raised regarding the exposure of operators, bystanders, and consumers. Urine measurement studies have been conducted, but since toxicokinetic data on glyphosate in humans is lacking, a meaningful interpretation of this data regarding exposure is not possible. OBJECTIVE: This study aims to determine the fraction of glyphosate and AMPA excretion in urine after consuming ordinary food with glyphosate residue, to estimate dietary glyphosate intake. METHODS: Twelve participants consumed a test meal with a known amount of glyphosate residue and a small amount of AMPA. Urinary excretion was examined for the next 48 h. RESULTS: Only 1% of the glyphosate dose was excreted in urine. The urinary data indicated the elimination half-life was 9 h. For AMPA, 23% of the dose was excreted in urine, assuming that no metabolism of glyphosate to AMPA occurred. If all of the excreted AMPA was a glyphosate metabolite, this corresponds to 0.3% of the glyphosate dose on a molar basis. CONCLUSION: This study provides a basis for estimating oral glyphosate intake using urinary biomonitoring data.


Assuntos
Monitoramento Biológico/métodos , Exposição Dietética/análise , Glicina/análogos & derivados , Herbicidas/urina , Organofosfonatos/urina , Resíduos de Praguicidas/urina , Adulto , Biomarcadores/urina , Cicer , Feminino , Farinha/análise , Contaminação de Alimentos/análise , Glicina/análise , Glicina/farmacocinética , Glicina/urina , Herbicidas/análise , Herbicidas/farmacocinética , Humanos , Masculino , Organofosfonatos/análise , Organofosfonatos/farmacocinética , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/farmacocinética , Glifosato
10.
Biomed Chromatogr ; 34(7): e4836, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32222076

RESUMO

The dissipation dynamic and residues of spiroxamine in open-field-grown strawberries were determined using liquid chromatography tandem mass spectrometry (LC-MS/MS). Spiroxamine application was performed according to Egyptian good agricultural practices recommendation. A QuEChERS-based extraction method along with direct analysis with an LC-MS/MS analytical method were optimized and validated, and the specificity of the techniques used was considered satisfactory. Good linearity (R2 > 0.999) was obtained for spiroxamine within the range of 0.001-0.1 µg/ml. The mean recoveries varied between 97.1 and 108.2%, with inter- and intra-day precision (RSD) <4.9%. The limit of quantitation for spiroxamine was 0.001 mg/kg. The results indicated that spiroxamine degradation in strawberry followed first-order kinetics (R2 > 0.9929) with an estimated half-life value of 4.71 days. Considering the Australian maximum residue limit (0.05 mg/kg) in strawberry and based on the results from residue trials with a preharvest interval of 14 days for strawberry, compliance can be expected. The present results could provide guidance to fully evaluate the risks of spiroxamine residues, preventing any potential health risk to consumers.


Assuntos
Cromatografia Líquida/métodos , Fragaria , Fungicidas Industriais/análise , Resíduos de Praguicidas/análise , Compostos de Espiro/análise , Egito , Inocuidade dos Alimentos , Fragaria/química , Fragaria/metabolismo , Fungicidas Industriais/farmacocinética , Modelos Lineares , Resíduos de Praguicidas/farmacocinética , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade , Compostos de Espiro/farmacocinética , Espectrometria de Massas em Tandem/métodos
11.
Biomed Chromatogr ; 34(3): e4745, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31725903

RESUMO

Using LC-MS/MS, a rapid and sensitive method for the simultaneous determination of pyraclostrobin and azoxystrobin residues in banana matrices (leaf and whole banana) and soil was established. The samples were extracted using acetonitrile and purified through C18 dispersive solid-phase extraction. The average recovery of the analytes in various matrices was in the range of 77.3%-103.9% with an RSD range of 0.9%-9.5%. The initial deposition amounts of pyraclostrobin and azoxystrobin at 2 h in the banana leaves of the mineral oil group were 1.43 and 1.31 times in Guangxi, and 2.10 and 1.81 times in Hainan for the water group, whereas those in the soil of the water group were 3.45 and 3.03 times in Guangxi, and 2.14 and 3.48 times in Hainan for the mineral oil group. The half-lives in the leaves and soil of the mineral oil group were not remarkably different from those of the water group. The terminal residue of the analytes on the whole banana was <0.02 mg/kg at 14 days after application from the two sites. The results of this work may indicate and promote the safety of using pyraclostrobin and azoxystrobin in banana production, especially with mineral oil spray adjuvants.


Assuntos
Óleo Mineral/química , Musa/química , Resíduos de Praguicidas , Pirimidinas , Estrobilurinas , Cromatografia Líquida/métodos , Frutas/química , Fungicidas Industriais/análise , Fungicidas Industriais/isolamento & purificação , Fungicidas Industriais/farmacocinética , Cinética , Limite de Detecção , Modelos Lineares , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Resíduos de Praguicidas/farmacocinética , Folhas de Planta/química , Pirimidinas/análise , Pirimidinas/isolamento & purificação , Pirimidinas/farmacocinética , Reprodutibilidade dos Testes , Solo/química , Extração em Fase Sólida , Estrobilurinas/análise , Estrobilurinas/isolamento & purificação , Estrobilurinas/farmacocinética , Espectrometria de Massas em Tandem/métodos
12.
Regul Toxicol Pharmacol ; 106: 55-67, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31028797

RESUMO

We describe a novel experimental method that mimics exposure to dried agrochemical residues on contact surfaces during re-entry into crops. It includes the creation of dry dislodgeable residues and subsequent transfer to human skin for in vitro measurement of dermal absorption within a standard Organisation for Economic Co-operation and Development test guideline (OECD TG) 428 study. A pre-determined volume of spray containing 14C-labelled active substance is transferred onto a polytetrafluorethylene-coated septum and air-dried. The septum is then gently placed onto the pre-wetted skin mounted in a flow-through Franz diffusion chamber. The septum is gently rotated thrice to transfer the dose. Preliminary tests determined transfer efficiency to ensure the appropriate test concentration on the skin. Then, a standard dermal absorption study is performed according to OECD TG 428. Results from 10 compounds indicate that the methodology can be robustly incorporated into a standard TG study. These data show that the dermal absorption from a dry dislodgeable residue is lower than that from the equivalent dose of the aqueous spray, regardless of formulation type or active substance. Studies following the scenario described above can be a suitable tool to better estimate dermal absorption from dry residues in re-entry worker and resident exposure assessment for agrochemicals.


Assuntos
Agroquímicos/metabolismo , Organização para a Cooperação e Desenvolvimento Econômico , Resíduos de Praguicidas/metabolismo , Absorção Cutânea , Pele/metabolismo , Agroquímicos/química , Agroquímicos/farmacocinética , Difusão , Humanos , Resíduos de Praguicidas/química , Resíduos de Praguicidas/farmacocinética , Pele/química
13.
Mar Pollut Bull ; 140: 503-508, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30803671

RESUMO

Concentration of organochlorine pesticides (OCPs) (α-, ß-, γ- hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDD), dichlorodiphenyldichloroethylene (DDE)) in four species of Pacific salmon (pink, chum, chinook, and sockeye) are presented. OCPs in salmon organs increased in the following order: muscle < liver < eggs < male gonads. Concentrations of the OCP in salmon organs increased in following order: DDE < γ-HCH < α-HCH. The level of pollutants in salmon is compared with the sanitary and epidemiological norms of Russia and other countries. Cancer and noncancer hazard ratios through consumption of salmon in Russian Far East for both men and women also were summarized. Noncancer and cancer hazard ratio values were far below threshold values (<1.0).


Assuntos
Inocuidade dos Alimentos , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Salmão/metabolismo , Poluentes Químicos da Água/análise , Animais , Feminino , Humanos , Hidrocarbonetos Clorados/farmacocinética , Masculino , Resíduos de Praguicidas/farmacocinética , Medição de Risco , Federação Russa , Distribuição Tecidual , Poluentes Químicos da Água/farmacocinética
14.
Biomed Chromatogr ; 33(6): e4492, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30673143

RESUMO

An analytical method for the determination of buprofezin residues in cabbage and cauliflower was developed and validated using gas chromatography with ion trap mass spectrometry. The analyte protectant d-sorbitol was used at a concentration level of 0.5 mg mL-1 in acetonitrile instead of in matrix for constructing the calibration curves of the buprofezin standard. The average recoveries ranged from 91.3 to 96.8%, with an RSD of ≤2.7%. The limits of detection and quantitation of the method in cabbage and cauliflower were 1.3, 1.7 and 4.3, 6.2 µg kg-1 , respectively. The residual levels and dissipation kinetics of buprofezin 25% wettabe powder in cabbage and cauliflower cultivated under open field conditions was investigated at the single (T1) and double (T2) recommended rates of application. Half-life periods were found to be 1.73 and 2.1 days in cabbage, whereas in cauliflower, these values were 1.85 and 2.36 days at T1 and T2, respectively. Based on the dissipation study, and the maximum residue limit value of 0.05 mg kg-1 , the proposed pre-harvest interval of buprofezin in cabbage was 3-6 days and that in cauliflower was 4-10 days. The results showed that buprofezin is safe for application at both recommended application rates.


Assuntos
Brassica/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Tiadiazinas/análise , Meia-Vida , Limite de Detecção , Modelos Lineares , Resíduos de Praguicidas/metabolismo , Resíduos de Praguicidas/farmacocinética , Reprodutibilidade dos Testes , Sorbitol/química , Tiadiazinas/metabolismo , Tiadiazinas/farmacocinética
15.
Environ Sci Pollut Res Int ; 26(6): 6077-6086, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30613891

RESUMO

The present study describes the uptake and distribution of fungicides, fluopyram, and tebuconazole in tomato and bell pepper plant tissues from the soil drench application of their combination product fluopyram17.7% + tebuconazole 17.7%. For extraction and cleanup of fluopyram, its metabolite fluopyram benzamide, and tebuconazole samples, the QuEChERS method was used in conjunction with LC-MS/MS. The limit of detection (LOD) and limit of quantification (LOQ) of the method determined were 1.5 µg kg-1 and 0.005 mg kg-1, respectively, and recoveries of all analytes from sample matrices remained within the acceptable range of 70-120%. Rapid uptake of the fungicides by tomato and bell pepper plants was observed from the first day onwards. In the tomato plant, the major part of the fungicides accumulated in the roots, whereas in bell pepper plant, it accumulated both in the roots and in the leaves. Accumulation of fluopyram and tebuconazole residues was lowest in tomato and bell pepper fruits which were much below their respective maximum residue limits (MRLs). The highest residue concentration of fluopyram and tebuconazole in tomato fruits was 0.060 and 0.009 mg kg-1; the corresponding values in bell pepper fruits were 0.080 and 0.013 mg kg-1. In field soil, fluopyram residues were 3.18-3.570 mg kg-1 initially which dissipated at the half-life of 36 days. Tebuconazole concentration was 1.57-1.892 mg kg-1 initially, and it dissipated at the half-life of 44.5-49.5 days. The major metabolite of fluopyram, fluopyram benzamide, was detected in plant tissues as well as in soil, and remained within 12% of the parent compound. The results of the study indicated that fluopyram and tebuconazole are less likely of entry into food chain through intake of tomato and bell pepper fruits if these crops are grown on soil contaminated with these fungicides.


Assuntos
Benzamidas/análise , Capsicum/química , Resíduos de Praguicidas/análise , Piridinas/análise , Poluentes do Solo/análise , Solanum lycopersicum/química , Triazóis/análise , Benzamidas/farmacocinética , Cromatografia Líquida , Frutas/química , Fungicidas Industriais/análise , Fungicidas Industriais/farmacocinética , Meia-Vida , Resíduos de Praguicidas/farmacocinética , Piridinas/farmacocinética , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Triazóis/farmacocinética
16.
Biomed Chromatogr ; 33(2): e4394, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30248717

RESUMO

As one of the main fungicides for the apple leaf disease control, thiophanate-methyl (TM) mainly exerts its fungicidal activity in the form of its metabolite carbendazim (MBC), whose dissipation kinetics is very distinct from that of its parent but has been paid little attention. The aim of this work was to investigate the dissipation kinetics of TM and its active metabolite MBC in apple leaves using a modified QuEChERS-UPLC-MS/MS method. The results showed that TM and MBC could be quickly extracted by this modified QuEChERS procedure with recoveries of 81.7-96.5%. The method linearity was in the range of 0.01-50.0 mg kg-1 with the quantification limit of 0.01 mg kg-1 . Then this method was applied to the analysis of fungicide dissipation kinetics in apple leaves. The results showed that the dissipation kinetics of TM for the test in 3 months can be described by a first-order kinetics model with a DT50 (dissipation half-life) range of 5.23-6.03 days and the kinetics for MBC can be described by a first-order absorption-dissipation model with the Tmax (time needed to reach peak concentration) range of 4.78-7.09 days. These models can scientifically describe the behavior of TM and MBC in apple leaves, which provides necessary data for scientific application.


Assuntos
Benzimidazóis/análise , Carbamatos/análise , Malus/química , Resíduos de Praguicidas/análise , Tiofanato/análise , Adsorção , Benzimidazóis/química , Benzimidazóis/farmacocinética , Carbamatos/química , Carbamatos/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Modelos Lineares , Resíduos de Praguicidas/química , Resíduos de Praguicidas/farmacocinética , Folhas de Planta/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos , Tiofanato/química , Tiofanato/farmacocinética
17.
J Environ Sci Health B ; 54(2): 89-97, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30460878

RESUMO

A shortened version of Quick, Easy, Cheap, Effective, Rugged, and Safe method (QuEChERS) for determining the dissipation and residue of imidacloprid present in Zizania latifolia and purple sweet potato was established by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The average recoveries of imidacloprid in the two crops ranged from 82.12 to 113.79%, with relative standard deviation (RSD) of <7.32%. The dissipation dynamics of imidacloprid in Z. latifolia plants and purple sweet potato plants followed first-order kinetics, with half-lives of 3.2-5.5 days in each of sampling locations. The terminal imidacloprid residues in Z. latifolia and purple sweet potato at each of location were <0.005-0.120 mg kg-1. According to the risk assessment results, both the acute dietary risk quotient and chronic dietary risk quotient values were <1, indicating that imidacloprid is unlikely to pose health risks to humans with normal recommended use. The present study may serve as a valuable reference for the safe and reasonable use of imidacloprid in Z. latifolia and purple sweet potato fields.


Assuntos
Cromatografia Líquida/métodos , Ipomoea batatas/química , Neonicotinoides/análise , Nitrocompostos/análise , Oryza/química , China , Produtos Agrícolas/química , Exposição Dietética , Contaminação de Alimentos/análise , Meia-Vida , Humanos , Cinética , Neonicotinoides/farmacocinética , Nitrocompostos/farmacocinética , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/farmacocinética , Medição de Risco , Espectrometria de Massas em Tandem/métodos
18.
Food Chem ; 260: 66-72, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29699683

RESUMO

An efficient method was developed and validated for simultaneous determination of tebuconazole, thiophanate-methyl and its metabolite carbendazim in grape and soil using QuEChERS procedure and liquid chromatography-tandem mass spectrometry. The average recoveries of the method were 83.2%-105.4%, the limit of detection (LOD) ranged from 2.1 × 10-5 to 8.7 × 10-4 mg L-1, and the limit of quantitation (LOQ) was 0.1 mg kg-1. The field results showed that tebuconazole and thiophanate-methyl in soil and grape were rapidly dissipated with half-lives less than 24.7 days. The terminal residues of all analytes in grape were lower than the maximum residue limit (MRL) set by China (2 mg kg-1 for tebuconazole; 3 mg kg-1 for both thiophanate-methyl and carbendazim). Risk assessment showed that tebuconazole, thiophanate-methyl and its metabolite would be unlikely to cause health problems. However, carbendazim, the higher active metabolites of thiophanate-methyl, should receive more concerns.


Assuntos
Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Tiofanato/análise , Triazóis/análise , Vitis/química , Benzimidazóis/análise , Carbamatos/análise , China , Cromatografia Líquida/métodos , Exposição Dietética/análise , Meia-Vida , Humanos , Limite de Detecção , Resíduos de Praguicidas/farmacocinética , Medição de Risco/métodos , Poluentes do Solo/análise , Espectrometria de Massas em Tandem/métodos , Tiofanato/metabolismo , Tiofanato/farmacocinética , Triazóis/metabolismo , Triazóis/farmacocinética
19.
Food Chem Toxicol ; 115: 329-335, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29574011

RESUMO

The goal of this work is to study the presence of 17 different pyrethroids and chlorpyrifos in animal origin food samples, including chicken, beef, fish, eggs and milk. The samples were analyzed by GC/NCI-MS/MS in order to determine their insecticide concentration levels, the relation between the amount of insecticides and the lipid content, as well as their isomeric composition. Bifenthrin, cypermethrin, cyhalothrin, permethrin, deltamethrin and chlorpyrifos have been detected in real samples. The highest levels find were verified for chlorpyrifos (45.7 µg L-1, 17.5 µg kg-1 ww) and cypermethrin (2.75 µg L-1, 14.7 µg kg-1 ww) in milk and beef, respectively. The estimate of daily intake showed that none of these insecticides exceeded the safety limits of the acceptable daily intake values. A strong correlation between the amount of pesticides and lipid content was found for beef, fish and chicken samples. Regarding the isomers, a predominance of cis isomers in samples contaminated with cypermethrin was verified.


Assuntos
Clorpirifos/análise , Exposição Dietética , Contaminação de Alimentos/análise , Inseticidas/análise , Resíduos de Praguicidas/análise , Piretrinas/análise , Adulto , Animais , Biotransformação , Brasil , Clorpirifos/farmacocinética , Laticínios/análise , Ovos/análise , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Inseticidas/farmacocinética , Masculino , Carne/análise , Nível de Efeito Adverso não Observado , Resíduos de Praguicidas/farmacocinética , Piretrinas/farmacocinética , Medição de Risco , Alimentos Marinhos/análise
20.
Chemosphere ; 190: 350-357, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29017112

RESUMO

Soil aging will influence the chemical speciation of pesticides, thus affecting the uptake route to be bioavailable to the organism. So far, studies on the possible effects of the uptake route on the distribution and elimination of pesticides in the organism that also considers effects of aging are limited. In our study, Eisenia fetida was exposed to 4.5 mg kg-1 lindane aging for 0, 30 and 180 d, and the accumulation, distribution and elimination of lindane in the earthworms were analyzed. The results showed that the 6 h Tenax-extracted fraction exhibited a good linear correlation with the lindane accumulated in the earthworms. With aging time increasing, the bioaccumulation of lindane decreased and the accumulative balance was more easily reached in the earthworms. Lindane distributions were found in the whole earthworm and the proportions of lindane content at sub-organism level and the mass distribution of each fraction were similar for 0 d and 180 d aged groups. The foregut accumulated the highest content of lindane (20%) relative to its low mass distribution proportion (10%). The elimination rate of lindane in the earthworms decreased with aging time extending. Our conclusion was that the 6 h Tenax extraction could be used to assess the bioavailability of aging lindane. Although soil aging decreased the bioavailability of lindane, the soil-bound lindane entered the earthworm through dietary route would take longer to depurate from the organisms than free lindane, which implied the potential ecological risk of bound pesticide residues.


Assuntos
Hexaclorocicloexano/farmacocinética , Oligoquetos/metabolismo , Animais , Disponibilidade Biológica , Inseticidas/metabolismo , Inseticidas/farmacocinética , Resíduos de Praguicidas/metabolismo , Resíduos de Praguicidas/farmacocinética , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética , Fatores de Tempo
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