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1.
Molecules ; 28(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37959688

RESUMO

This report presents the development of a highly effective method employing high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to investigate chlorantraniliprole's dissipation, risk assessment, and residue distribution in whole lychee fruit and its pulp. Mean recoveries of the samples ranged from 80 to 105%, exhibiting a relative standard deviation (RSD) of below 8%. The limits of quantification (LOQ) for lychee and pulp were determined as 0.001 mg/kg, and half-lives (t1/2) ranged from 8.0 to 12.2 days. Terminal residue concentrations in whole litchi and pulp were determined as 0.008-0.45 mg/kg and ≤0.001 mg/kg. These residues were treated twice and thrice at two different dosage levels with pre-harvest intervals (PHIs) of 7, 14, and 21 days. The potential chronic risk posed by chlorantraniliprole to humans was non-negligible, as indicated by the risk quotient (RQ) value not exceeding 1. Therefore, this study provides significant fresh data about the safe application of chlorantraniliprole in the production of lychee, which will help China develop maximum residual limits (MRLs).


Assuntos
Litchi , Resíduos de Praguicidas , Humanos , Frutas/química , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Contaminação de Alimentos/análise , Meia-Vida , Medição de Risco , China
2.
J Environ Manage ; 342: 118180, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37207459

RESUMO

Household waste source separation substantially reduces the amount of rubbish sent to landfills and incinerators. It enables value recovery from useful waste for transitioning to a more resource efficient and circular economy. Confronted by the severe waste management problems, China recently implemented its most strict compulsory waste sorting program in big cities to date. Despite the failures of waste sorting projects in China in the past, it is unclear what the implementation barriers are, how they interact, and how they can be overcome. This study addresses this knowledge gap through a systematic barrier study involving all the relevant stakeholders in Shanghai and Beijing. It uncovers the complex interrelationships between barriers using the fuzzy decision-making trial and evaluation laboratory (Fuzzy DEMATEL) method. "Hasty and inappropriate planning" and "lack of policy support at the grassroots level", two new barriers that are not reported in the literature, are found to be the most influential barriers. Policy implications are discussed based on the study findings to inform the policy deliberations on the implementation of compulsory waste sorting.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Resíduos Sólidos/análise , China , Reciclagem/métodos , Gerenciamento de Resíduos/métodos , Cidades
3.
Molecules ; 28(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37110581

RESUMO

A derivatization method combined with high-performance liquid chromatography-fluorescence detection (HPLC-FLD) was used to evaluate the dissipation, residue distribution and risk assessment of emamectin benzoate in whole longan and pulp. The average recoveries were 82-111% with relative standard deviation (RSD) less than 11%. The limit of quantification (LOQ) was 0.001 mg/kg in longan and pulp. The half-lives were 3.3-4.2 days. The terminal residues in whole longan were <0.001-0.025 mg/kg applied two and three times at two levels of dosage with PHIs of 10, 14, and 21 days. The residues in whole longan had a higher quantity than those in the pulp, and the terminal residues of pulp were all lower than LOQ (0.001 mg/kg). The chronic risk of emamectin benzoate was not negligible to humans depending on ADI% value, which was higher than 1; and the acute risk was acceptable to the consumer. This study could provide guidance for the safe use of emamectin benzoate in longan and serve as a reference for the establishment of maximum residue limits (MRLs) in China.


Assuntos
Resíduos de Praguicidas , Humanos , Cromatografia Líquida de Alta Pressão , Resíduos de Praguicidas/análise , Meia-Vida , Medição de Risco
4.
Molecules ; 29(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38202744

RESUMO

The present study describes the development of a highly effective approach for determining the residue distribution and dissipation of trifloxystrobin and tebuconazole, and their risk assessment in brown rice, husk, straw, and grain using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The current study provides considerable novel information regarding the safe utilization of a mixture of trifloxystrobin and tebuconazole in paddy production. The samples demonstrated a range of mean recoveries between 72% and 86%, with a 1.1-9.2% relative standard deviation (RSD). The limits of quantification (LOQ) and half-lives (t1/2) for brown rice, husk, straw, and grain were, respectively, established to be 0.001-0.01 mg/kg and 4.1-7.7 days. The concentrations of terminal residues in the brown rice, husk, straw, and grain were, respectively, found to be 0.02-0.05, 0.03-0.11, 0.02-0.07, and 0.02-0.05 mg/kg after being treated twice at 168.75 g a.i./ha with 21 and 28 days of pre-harvest intervals (PHIs). Trifloxystrobin and tebuconazole presented a non-negligible chronic risk to human subjects, as evidenced by a risk quotient (RQ) value of less than 1.


Assuntos
Acetatos , Grão Comestível , Iminas , Estrobilurinas , Espectrometria de Massas em Tandem , Triazóis , Humanos , Medição de Risco , Água
5.
J Agric Food Chem ; 70(51): 16369-16381, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36521106

RESUMO

The presence of pesticides in foodstuffs has received increasing amount of attention worldwide. In this study, an efficient and sensitive QuEChERS/HPLC-MS/MS-based method was established for the simultaneous detection of indaziflam, cyantraniliprole, spirotetramat, and their metabolites on fruits and vegetables. The purification procedure and detection condition parameters were optimized. Good precision and reproducibility were found for the method, and the average recoveries of the target analytes ranged from 71 to 118%, with the relative standard deviation ranging from 2 to 12%. The limits of quantification and the limits of detection were 1-5 and 0.3-1.5 µg kg-1, respectively. The proposed method was used to detect three pesticides and their metabolites in fruit and vegetable samples collected from China's major producing regions. Furthermore, the dietary risk posed by the pesticide residues on fruits and vegetables was evaluated by risk quotients (RQs) and risk probabilities (RPs). The RQ and RP values were less than 100% for Chinese consumers. This study not only provides a reliable analytical method for monitoring purposes but also serves as a significant guide for food safety and export.


Assuntos
Resíduos de Praguicidas , Praguicidas , Espectrometria de Massas em Tandem/métodos , Frutas/química , Verduras/química , Reprodutibilidade dos Testes , Praguicidas/análise , Resíduos de Praguicidas/análise
6.
BMC Pharmacol Toxicol ; 23(1): 45, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35794660

RESUMO

PURPOSE: The combination of lisinopril and amlodipine has a marked additional effect on blood pressure and fewer side effects than individual monotherapy. This study was conducted to compare the pharmacokinetic parameters and evaluate the bioequivalence between two Lisinopril/amlodipine tablets in healthy Chinese subjects. METHODS: A single center, randomized, open-label, single-dose, two-period crossover bioequivalence study was designed in healthy Chinese subjects under both fasting and fed conditions. Blood samples were collected before drug administration and at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 24, 36, 48, 72, 96, 144, 168 h after administration. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was applied to determine the plasma concentration of lisinopril and amlodipine. Maximum concentration (Cmax) and area under the concentration-time curve (AUC) were used to evaluate bioequivalence. Adverse events were recorded. RESULTS: Ninety-two healthy subjects were enrolled, and 75 completed the study. The 90% confidence intervals (CIs) of the ratio of geometric means (GMRs) of Cmax, AUC0-t, and AUC0-∞ of lisinopril and amlodipine under both fasting and fed conditions fell within the conventional bioequivalence criteria of 0.80-1.25. A high-fat meal appeared to decrease the Cmax and AUC of lisinopril. No severe adverse events were observed. CONCLUSION: The trial demonstrated that the test and the reference lisinopril/amlodipine tablets were bioequivalent and well tolerated in Chinese people under fasting and fed conditions. TRIAL REGISTRATION: Clinical Trails.gov identifier, NCT04885660 (retrospectively registered in 13/05/ 2021).


Assuntos
Jejum , Lisinopril , Anlodipino , China , Cromatografia Líquida , Voluntários Saudáveis , Humanos , Comprimidos , Espectrometria de Massas em Tandem , Equivalência Terapêutica
7.
Clin Pharmacol Drug Dev ; 11(3): 358-363, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34637608

RESUMO

Rivaroxaban is a direct factor Xa inhibitor used for the management of thromboembolic disorders. The aim of this study was to evaluate the safety, pharmacokinetic profile, and bioequivalence of a generic and a branded rivaroxaban formulation (Xarelto) under fasted and fed conditions in healthy Chinese volunteers. An open-label, randomized, single-dose, 4-period complete, and replicate crossover study in healthy Chinese volunteers was performed. A single oral dose of 20 mg of 2 rivaroxaban formulations was administered to 72 healthy volunteers, with 36 in the fasted group and 36 consuming a high-fat diet. The evaluated pharmacokinetic parameters, including maximum rivaroxaban concentration, the area under the concentration-time curve (AUC) from time 0 to the last measurable concentration, and AUC from time 0 to infinity, were assessed for BE. The plasma concentrations of rivaroxaban were measured by a validated liquid chromatography-tandem mass spectrometry method. The geometric mean ratios with 90% confidence intervals of the maximum rivaroxaban concentration, AUC from time 0 to the last measurable concentration, and AUC from time 0 to infinity were all within the range of 80% to 125% under fasted and fed conditions. The within-subject variability of the test and reference products was compared, and the upper limit of the 90% confidence intervals for the test-to-reference ratio of the within-subject variability was <2.5, which indicated that the rivaroxaban test and the rivaroxaban reference formulation were bioequivalent. No serious adverse events were reported during either fasted or fed conditions of the study.


Assuntos
Rivaroxabana , Área Sob a Curva , China , Estudos Cross-Over , Humanos , Rivaroxabana/efeitos adversos , Comprimidos , Equivalência Terapêutica
8.
Ecotoxicol Environ Saf ; 191: 110157, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954218

RESUMO

Urban parks and schools sever as the mainly activity areas for children, but risk assessment posed by heavy metals (HMs) from soil and dust in these area has rarely been investigated. In this study, six urban parks and seven schools in Jiaozuo, China, were taken as research objects to understand the contamination level and bioaccessibility of HMs from soil and dust in urban parks and schools. The results indicated that Zn, Cu, Pb, Cd, As, Ni and Co from soil and dust were above the background values, especially Zn and Cd in dust, and As and Cd in soil. Serious Cd pollution was discovered, and respective Cd concentrations in soil and dust were 17.83 and 7.52 times the background value. Additionally, the average concentration and bioaccessibility of Zn, Mn, Pb, Cd, Cr, Ni and Co in dust were both higher than in soil. High concentration and high bioaccessibility of HMs in dust suggested that HMs contamination were serious and universal in Jiaozuo. The concentrations of most HMs were higher in the gastric phase, except for Cu and Cd which remained higher in the intestinal phase. Both in the gastric phase and intestinal phase, Mn, As and Cd in soil and dust both have high bioaccessibility which all exceed 10%. The carcinogenic and non-carcinogenic risks base on the total HMs for children (soil: 7.93, 1.96E-05; dust: 6.44, 3.58E-05) were greater than those for adults (soil: 6.35E-01, 1.32E-05; dust: 5.06E-01, 2.42E-05), and urban parks and schools posed high potential risk for children. Therefore, assessment the risk posed by HMs contamination of soil and dust in urban parks and schools is vital and urgent for children.


Assuntos
Poeira/análise , Exposição Ambiental/análise , Metais Pesados/análise , Poluentes do Solo/análise , Adulto , Disponibilidade Biológica , Carcinógenos/análise , Carcinógenos/metabolismo , Criança , China , Exposição Ambiental/efeitos adversos , Humanos , Metais Pesados/metabolismo , Parques Recreativos , Medição de Risco , Instituições Acadêmicas , Poluentes do Solo/metabolismo
9.
Sci Total Environ ; 676: 1-10, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31029894

RESUMO

Differences in the concentrations of heavy metals between newly built and original parks remain incompletely understood. In this work, two newly built and four original parks in Jiaozuo, China, were taken as research objects. Using the geo-accumulation index, ecological risk assessment index and human health risk model, differences in heavy metal pollution between the two types of parks were determined. In the surveyed region, five heavy metals, namely, Zn, Cu, As, Ni and Co, polluted the environment. Serious As pollution was discovered, and respective As concentrations in the soils of newly built and original parks were 5.9 and 3 times the background value. The concentrations of Zn, Mn, As, Pb, Cr and Ni in newly built parks were higher than those in the four original parks, although the concentrations of Cu and Co between the two types of parks were not significantly different. The carcinogenic and non-carcinogenic risks of these metals in newly built parks (adults: 4.27E-05, 1.08; children: 2.53E-04, 8.94) were greater than those in original parks (adults: 2.57E-05, 0.67; children: 1.52E-04, 5.39), and newly built parks posed higher potential risk than original parks. Therefore, the concentration of heavy metals in soil must be assessed before former industrial sites are transformed into parks.

10.
Food Chem ; 244: 71-74, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29120807

RESUMO

An efficient method has been developed for determining tridemorph in banana using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The dissipation and terminal residue of tridemorph in banana fields were carried out at good agricultural practice (GAP) conditions. The average recoveries ranged from 84.4% to 90.0% with relative standard deviations (RSDs) of 3.0%-7.0% at three different spiking levels. The results indicated that the tridemorph dissipated quickly in banana with half-lives of 7.0-7.7days. The results of residual distribution ranged from 0.01 to 0.26mg/kg, 0.01-0.62mg/kg and <0.01mg/kg in whole banana, peel and pulp, respectively. The relationship between application factor and residue was discussed. The results of risk assessment showed that the risk quotient (RQ) value was all below RQ=1. Given that China has not set an maximum residue limit (MRL) value for tridemorph in banana, this study could provide guidance for the reasonable use of tridemorph.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Morfolinas/análise , Musa/química , Espectrometria de Massas em Tandem/métodos , China , Contaminação de Alimentos/análise , Meia-Vida , Morfolinas/metabolismo , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/metabolismo , Medição de Risco
11.
Yao Xue Xue Bao ; 50(10): 1290-6, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26837176

RESUMO

A rapid, sensitive and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous determination of clevidipine butyrate and its primary metabolite clevidipine acid in dog blood. After one-step protein precipitation with methanol, the chromatographic separation was carried out on an Ecosil C18 column (150 mm x 4.6 mm, 5 µm) with a gradient mobile phase consisting of methanol and 5 mmol · L(-1) ammonium formate. A chromatographic total run time of 13.0 min was achieved. The quantitation analysis was performed using multiple reaction monitoring (MRM) at the specific ion transitions of m/z 454.1 [M-H]- --> m/z 234.1 for clevidipine butyrate, m/z 354.0 [M-H]- --> m/z 208.0 for clevidipine acid and m/z 256.1 [M-H]- --> m/z 227.1 for elofesalamide (internal standard, IS) in the negative ion mode with electrospray ionization (ESI) source. The linear calibration curves for clevidipine butyrate and clevidipine acid were obtained in the concentration ranges of 0.5-100 ng · mL and 1-200 ng · mL(-1), separately. The lower limit of quantification of clevidipine butyrate and clevidipine acid were 0.5 ng · mL(-1) and 1 ng · mL(-1). The intra and inter-assay precisions were all below 12.9%, the accuracies were all in standard ranges. Stability testing indicated that clevidipine butyrate and clevidipine acid in dog blood with the addition of denaturant methanol was stable under various processing and/or handling conditions. The validated method has been successfully applied to a pharmacokinetic study of clevidipine butyrate injection to 8 healthy Beagle dogs following intravenous infusion at a flow rate of 5 mg · h(-1) for 0.5 h.


Assuntos
Piridinas/sangue , Animais , Butiratos/sangue , Butiratos/farmacocinética , Calibragem , Cromatografia Líquida , Cães , Infusões Intravenosas , Piridinas/farmacocinética , Espectrometria de Massas em Tandem
12.
Nanotechnology ; 25(42): 425101, 2014 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-25274166

RESUMO

Magnetic iron oxide nanoparticles (IONPs) have been widely used for various biomedical applications such as magnetic resonance imaging and drug delivery. However, their potential toxic effects, including genotoxicity, need to be thoroughly understood. In the present study, the genotoxicity of IONPs with different particle sizes (10, 30 nm) and surface coatings (PEG, PEI) were assessed using three standard genotoxicity assays, the Salmonella typhimurium reverse mutation assay (Ames test), the in vitro mammalian chromosome aberration test, and the in vivo micronucleus assay. In the Ames test, SMG-10 (PEG coating, 10 nm) showed a positive mutagenic response in all the five test bacterial strains with and without metabolic activation, whereas SEI-10 (PEI coating, 10 nm) showed no mutagenesis in all tester strains regardless of metabolic activation. SMG-30 (PEG coating, 30 nm) was not mutagenic in the absence of metabolic activation, and became mutagenic in the presence of metabolic activation. In the chromosomal aberration test, no increase in the incidence of chromosomal aberrations was observed for all three IONPs. In the in vivo micronucleus test, there was no evidence of increased micronuclei frequencies for all three IONPs, indicating that they were not clastogenic in vivo. Taken together, our results demonstrated that IONPs with PEG coating exhibited mutagenic activity without chromosomal and clastogenic abnormalities, and smaller IONPs (SMG-10) had stronger mutagenic potential than larger ones (SMG-30); whereas, IONPs with SEI coating (SEI-10) were not genotoxic in all three standard genotoxicity assays. This suggests that the mutagenicity of IONPs depends on their particle size and surface coating.


Assuntos
Compostos Férricos/toxicidade , Nanopartículas Metálicas/toxicidade , Testes de Mutagenicidade , Animais , Linhagem Celular , Aberrações Cromossômicas/induzido quimicamente , Cricetulus , Eritrócitos/efeitos dos fármacos , Compostos Férricos/química , Masculino , Nanopartículas Metálicas/química , Camundongos , Tamanho da Partícula , Ratos Sprague-Dawley , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
13.
Waste Manag ; 34(12): 2627-33, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25192798

RESUMO

The anaerobic digestion performances of kitchen waste (KW) and fruit/vegetable waste (FVW) were investigated for establishing engineering digestion system. The study was conducted from lab-scale to pilot-scale, including batch, single-phase and two-phase experiments. The lab-scale experimental results showed that the ratio of FVW to KW at 5:8 presented higher methane productivity (0.725 L CH4/g VS), and thereby was recommended. Two-phase digestion appeared to have higher treatment capacity and better buffer ability for high organic loading rate (OLR) (up to 5.0 g(VS) L(-1) d(-1)), compared with the low OLR of 3.5 g(VS) L(-1) d(-1) for single-phase system. For two-phase digestion, the pilot-scale system showed similar performances to those of lab-scale one, except slightly lower maximum OLR of 4.5 g(VS) L(-1) d(-1) was allowed. The pilot-scale system proved to be profitable with a net profit of 10.173$/ton as higher OLR (⩾ 3.0 g(VS) L(-1) d(-1)) was used.


Assuntos
Reatores Biológicos , Eliminação de Resíduos/métodos , Resíduos Sólidos/análise , Anaerobiose , Reatores Biológicos/economia , Frutas/química , Metano/análise , Eliminação de Resíduos/economia , Verduras/química
14.
Environ Monit Assess ; 185(12): 10473-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23880916

RESUMO

The dissipation, residues, and distribution of spirodiclofen, a new type of insecticide and acaricide that belongs to the class of ketoenols or tetronic acids, in citrus were investigated in this study. Risk assessment of sprodiclofen was also conducted based on those data. The open-field experiments were conducted in Guangdong, Fujian, and Guangxi of China. Results showed that the half-lives in citrus ranged from 6.5 to 13.6 days at three sites. The terminal residues of spirodiclofen were all below the FAO/WHO maximum residue limit of 0.5 mg/kg in citrus, when they were determined 14 days after final application. Distribution of spirodiclofen in peel and flesh was analyzed, and residues were found to be concentrated on peel. Risk assessment was performed by calculation of risk quotient, which showed that the use of spirodiclofen is comparably safe for humans.


Assuntos
4-Butirolactona/análogos & derivados , Citrus/química , Inseticidas/análise , Resíduos de Praguicidas/análise , Compostos de Espiro/análise , 4-Butirolactona/análise , China , Monitoramento Ambiental , Contaminação de Alimentos/análise , Contaminação de Alimentos/estatística & dados numéricos , Meia-Vida , Medição de Risco
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