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1.
Environ Sci Pollut Res Int ; 30(1): 1520-1539, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35917068

RESUMO

Evaluating environmental water quality means to assess and protect the environment against unfriendly impacts from various organic impurities emerging from industrial emissions and those released during harvesting. Potential risks related with release of polycyclic aromatic hydrocarbons (PAHs), pesticides and pharmaceuticals (PhAcs), and personal care products (PCPs) into the environment have turned into an increasingly serious issue in ecological safety. Monitoring helps in control of chemicals and ecological status compliance to safeguard specific water uses, for example, drinking water abstraction. A longitudinal review was carried out for 55 different persistent organic pollutants (POPs) for the Ganga River which passes through the urban areas of Prayagraj and Varanasi, India, through validated analytical approaches and measurement uncertainty (MU) estimation to assess their potential use for routine analysis. Furthermore, environmental risk assessment (ERA) carried out in the present study has revealed risk quotient (RQ) higher than 1 in a portion of the aquatic bodies. Using a conservative RQ strategy, POPs were assessed for having extensive risks under acute and chronic exposure, proposing that there is currently critical ecological risk identified with these compounds present in the Ganga River. In general, these outcomes demonstrate a significant contribution for focusing on measures and feasible techniques to minimize the unfavorable effects of contaminants on the aquatic environment.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Rios/química , Poluentes Químicos da Água/análise , Cidades , Qualidade da Água , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise
2.
Chemosphere ; 231: 207-215, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31129401

RESUMO

Fipronil is a highly effective, broad-spectrum insecticide used to control pests, globally. The increased usage has led to contamination of soil, water, fruits, and vegetables. The wide and frequent usage of fipronil across the globe calls for attention regarding risk assessment of undesirable effects on non-target microorganisms. In this context, the present study was carried to understand the impact of fipronil on non-pathogenic Escherichia coli. The non-pathogenic E. coli are important commensal of the intestinal tract of humans and animals and are also indicator organisms in the environment. Our study indicates that exposure of E. coli to fipronil (100 µM concentration) leads to significant reactive oxygen species production, loss of membrane potential and viability. Further, we have witnessed the bioaccumulation and biotransformation of fipronil by E. coli at non-lethal concentrations. The bio-transformed products (fipronil sulfone and fipronil sulfide) are also the major metabolites (along with amide) reported in the feces of the mammals when exposed to fipronil. Thus, there is a possibility that the gut E. coli might play a role in the degradation and thereby removal of fipronil. In addition, the bioaccumulation of fipronil in bacteria is of concern and need to be further explored because it can lead to biomagnification in the higher trophic level and can disturb the ecological balance. In our knowledge, this is the first report on the determination of fipronil and its metabolites in bacteria through GC-MS/MS.


Assuntos
Escherichia coli/efeitos dos fármacos , Inseticidas/toxicidade , Pirazóis/toxicidade , Biotransformação , Cromatografia Gasosa , Ecologia , Escherichia coli/metabolismo , Espectrometria de Massas em Tandem
3.
Toxicology ; 412: 79-88, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30503586

RESUMO

Alternariol (AOH) is a mycotoxin that contaminates various food stuffs as well as animal feed and may cause toxicity after consumption. However, a dermal toxic potential of AOH has not been explored so far. In the present study, skin toxicity after topical exposure of AOH and the involved mechanism/s are revealed. Single topical application of different AOH doses (12.5, 25, 50 µg/animal) caused increased bi-fold thickness as well as hyperplasia and higher production of prostaglandin E2 (PGE2) along with cAMP in the skin demonstrating its inflammatory potential. Western blot analysis showed that exposure of AOH lead to phosphorylation of CREB and increased the expression of COX-2, cyclin D1 as well as prostanoid EP2 receptor. Further studies on primary mouse keratinocytes (PMK) revealed that very low concentrations of AOH (50-500 nM) resulted in significant PMK proliferation. Additionally, using specific antagonist or agonist of prostanoid receptors, we delineated that EP2 receptor play a key role in AOH-induced PMKs proliferation. Collectively, our findings show that AOH can lead to dermal toxicity in mice by activating the EP2/cAMP/p-CREB signaling cascade.


Assuntos
Inflamação/induzido quimicamente , Queratinócitos/efeitos dos fármacos , Lactonas/toxicidade , Pele/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Feminino , Inflamação/metabolismo , Inflamação/patologia , Queratinócitos/metabolismo , Camundongos , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Pele/metabolismo , Pele/patologia
4.
Clin Chim Acta ; 487: 349-356, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30321523

RESUMO

BACKGROUND: To study the association between kidney injury biomarkers and urinary OH-PAH metabolites in kitchen workers, with microalbuminuria. METHODS: A cross-sectional pilot study was conducted among 120 male kitchen workers in a mega kitchen located at Coimbatore, India. Personal and sub-clinical details of study subjects were collected using a questionnaire. Albumin, creatinine, and albumin-creatinine ratio (ACR) were measured using urine dipstick test for the determination of microalbuminuria. Urinary hydroxylated PAHs metabolites (1-NAP, 9-HF, 3-HF, 2-HF, 9-PHN, and 1-OHP) were measured using GC-MS/MS and urinary kidney biomarkers (uNGAL, uCyst-C, uKIM-1, uOPN, and uTIMP-1) were measured using Multiplex Reader. RESULTS: Concentrations of urinary PAHs metabolites (1-NAP, 3-HF, 2-HF, 9-PHN, and 1-OHP) and kidney biomarkers (uKIM-1, uTIMP-1, uCyst-C and uNGAL) were significantly higher among kitchen workers with MAU compared to non-kitchen workers with MAU. Urinary kidney biomarkers viz., uKIM-1, uTIMP-1, uCyst-C, uNGAL, and uOPN showed higher median concentration among the kitchen workers with MAU compared to kitchen workers without MAU. Significant positive correlation was observed for 9-HF with uKIM-1 and uTIMP-1 and 1-OHP with uKIM-1. ACR was also well correlated with urinary kidney biomarkers. ROC analysis showed higher sensitivity and specificity for uKIM-1, uCyst-C, and uNGAL as biomarkers for early prediction of acute kidney injury among kitchen workers. CONCLUSIONS: The PAHs exposure among kitchen workers can lead to kidney injury. This was evident from the association of OH-PAHs and kidney injury biomarkers in kitchen workers with microalbuminuria.


Assuntos
Injúria Renal Aguda/urina , Albuminúria/urina , Hidrocarbonetos Policíclicos Aromáticos/urina , Adolescente , Adulto , Biomarcadores/urina , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Adulto Jovem
5.
J Chromatogr A ; 1561: 20-27, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-29789169

RESUMO

A simple and rapid method for the extraction of organochlorine compounds (OCs) including poly-chlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in fish liver using ultrasound assisted dispersive liquid-liquid microextraction based on the solidification of floating organic droplet (US-DLLME-SFO) was developed. For reducing the complexity of the matrix, the sample was pre-treated prior to microextraction. Factors affecting US-DLLME-SFO were optimized by using statistical design of experiment (DoE). The analysis was carried out by Gas Chromatography (GC) equipped with micro electron capture detector (µ-ECD). The optimized parameters were 4.8 min of ultrasound, 3.0 mL of Milli-Q and 24 µL of 1-undecanol as an extraction solvent as determined by DoE. US-DLLME-SFO was validated in terms of limit of detection, limit of quantification, dynamic linearity range, coefficient of determination (linearity) and extraction recovery in fish liver for OCs, and the respective values were (1.06-3.84 ng g-1), (3.50-12.67 ng g-1), (1.0-500 ng g-1), (R2 = 0.994-0.999), (88.5-108.4%). Interday and intraday precisions were evaluated as relative standard deviation (% RSD) and the values were ≤10%.


Assuntos
Cromatografia Gasosa/métodos , Elétrons , Peixes/metabolismo , Hidrocarbonetos Clorados/análise , Microextração em Fase Líquida/métodos , Compostos Orgânicos/química , Bifenilos Policlorados/análise , Sonicação/métodos , Animais , Fígado/metabolismo
6.
J Chromatogr A ; 1528: 10-17, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29096924

RESUMO

In the present study, a method has been efficiently developed for the first time to determine nine bisphenol analogues [bisphenol A (BPA), bisphenol C (BPC), bisphenol AF (BPAF), bisphenol E (BPE), bisphenol F (BPF), bisphenol G (BPG), bisphenol M (BPM), bisphenol S (BPS), and bisphenol Z (BPZ)] together in bottled carbonated beverages (collected from the local market of Lucknow, India) using dispersive liquid-liquid microextraction process. This is based on solidification of floating organic droplet (DLLME-SFO) followed by injector port silylation coupled with gas chromatography-tandem mass spectrometry. The process investigated parameters of DLLME-SFO (including the type of extraction and disperser solvents with their volumes, effect of pH, ionic strength, and the sample volume), factors influencing to injection port derivatization like, collision energy, injector port temperature, derivatizing reagent with sample injection volume, and type of organic solvent. BPA, BPF, BPZ, and BPS were detected in each sample; whereas, other bisphenols were also detected in some carbonated beverage samples. After optimizing the required conditions, good linearity of analytes was achieved in the range of 0.097-100ngmL-1 with coefficients of determination (R2)≥0.995. Intra-day and inter day precision of the method was good, with relative standard deviation (% RSD)≤10.95%. The limits of detection (LOD) and limits of quantification (LOQ) values of all bisphenols were ranged from 0.021 to 0.104ngmL-1 and 0.070 to 0.343ngmL-1, respectively. The recovery of extraction was good (73.15-95.08%) in carbonated beverage samples and good enrichment factors (96.36-117.33) were found. Thus, the developed method of microextraction was highly precise, fast, and reproducible to determine the level of contaminants in bottled carbonated beverages.


Assuntos
Bebidas Gaseificadas/análise , Cromatografia Gasosa , Análise de Alimentos/métodos , Microextração em Fase Líquida/instrumentação , Fenóis/análise , Espectrometria de Massas em Tandem , Compostos Benzidrílicos/análise , Cicloexanos/análise , Limite de Detecção , Solventes/química , Sulfonas/análise
7.
J Chromatogr A ; 1513: 157-171, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28735710

RESUMO

Two low density organic solvents based liquid-liquid microextraction methods, namely Vortex assisted liquid-liquid microextraction based on solidification of floating organic droplet (VALLME-SFO) and Dispersive liquid-liquid microextraction based on solidification of floating organic droplet(DLLME-SFO) have been compared for the determination of multiclass analytes (pesticides, plasticizers, pharmaceuticals and personal care products) in river water samples by using liquid chromatography tandem mass spectrometry (LC-MS/MS). The effect of various experimental parameters on the efficiency of the two methods and their optimum values were studied with the aid of Central Composite Design (CCD) and Response Surface Methodology(RSM). Under optimal conditions, VALLME-SFO was validated in terms of limit of detection, limit of quantification, dynamic linearity range, determination of coefficient, enrichment factor and extraction recovery for which the respective values were (0.011-0.219ngmL-1), (0.035-0.723ngmL-1), (0.050-0.500ngmL-1), (R2=0.992-0.999), (40-56), (80-106%). However, when the DLLME-SFO method was validated under optimal conditions, the range of values of limit of detection, limit of quantification, dynamic linearity range, determination of coefficient, enrichment factor and extraction recovery were (0.025-0.377ngmL-1), (0.083-1.256ngmL-1), (0.100-1.000ngmL-1), (R2=0.990-0.999), (35-49), (69-98%) respectively. Interday and intraday precisions were calculated as percent relative standard deviation (%RSD) and the values were ≤15% for VALLME-SFO and DLLME-SFO methods. Both methods were successfully applied for determining multiclass analytes in river water samples.


Assuntos
Cromatografia Líquida/métodos , Microextração em Fase Líquida/métodos , Compostos Orgânicos/química , Rios/química , Espectrometria de Massas em Tandem/métodos , Água/análise , Reprodutibilidade dos Testes , Solventes/química
8.
J Chromatogr A ; 1509: 35-42, 2017 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-28641832

RESUMO

A sensitive, rapid and efficient ionic liquid-based vortex assisted liquid-liquid microextraction (IL-VALLME) with Liquid Chromatography Mass spectrometry (LC-MS/MS) method is proposed for the determination of bisphenols in thermal paper. Extraction factors were systematically optimized by response surface methodology. Experimental factors showing significant effects on the analytical responses were evaluated using design of experiment. The limit of detection for Bisphenol-A (BPA) and Bisphenol-S (BPS) in thermal paper were 1.25 and 0.93µgkg-1 respectively. The dynamic linearity range for BPA was between 4 and 100µgkg-1 and the determination of coefficient (R2) was 0.996. The values of the same parameters were 3-100µgkg-1 and 0.998 for BPS. The extraction recoveries of BPA and BPS in thermal paper were 101% and 99%. Percent relative standard deviation (% RSD) for matrix effect and matrix match effects were not more than 10%, for both bisphenols. The proposed method uses a statistical approach for the analysis of bisphenols in environmental samples, and is easy, rapid, requires minimum organic solvents and efficient.


Assuntos
Compostos Benzidrílicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Líquidos Iônicos/química , Microextração em Fase Líquida/métodos , Fenóis/isolamento & purificação , Sulfonas/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , Compostos Benzidrílicos/química , Microextração em Fase Líquida/instrumentação , Papel , Fenóis/análise , Fenóis/química , Sulfonas/análise
9.
Anal Bioanal Chem ; 409(11): 2905-2918, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28283717

RESUMO

An efficient and inexpensive method using vortex-assisted surfactant-enhanced emulsification microextraction (VASEME) based on solidification of floating organic droplet coupled with ultraperformance liquid chromatography-tandem mass spectrometry is proposed for the analysis of glucocorticoids in water samples (river water and hospital wastewater). VASEME was optimized by the experimental validation of Plackett-Burman design and central composite design, which has been co-related to experimental design. Plackett-Burman design showed that factors such as vortex time, surfactant concentration, and pH significantly affect the extraction efficiency of the method. Method validation was characterized by an acceptable calibration range of 1-1000 ng L-1, and the limit of detection was in the range from 2.20 to 8.12 ng L-1 for glucocorticoids. The proposed method was applied to determine glucocorticoids in river water and hospital wastewater in Lucknow, India. It is reliable and rapid and has potential application for analysis of glucocorticoids in environmental aqueous samples. Graphical Abstract Low density based extraction of gluococorticoids by using design of experiment.


Assuntos
Cromatografia Líquida/métodos , Emulsificantes/química , Glucocorticoides/análise , Microextração em Fase Líquida/métodos , Espectrometria de Massas/métodos , Poluentes Químicos da Água/análise , Água/química , Monitoramento Ambiental/métodos , Glucocorticoides/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Poluentes Químicos da Água/química
10.
Chemosphere ; 169: 642-650, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27912189

RESUMO

A lignin peroxidases-producing Serratia liquefaciens was used for bioremediation of pulp and paper (P&P) mill effluent. The treatment led to reduction of chemical oxygen demand (COD), colour, lignin and phenolic content by 84%, 72%, 61% and 95%, respectively. The effluent detoxification was studied by genotoxicity assays using Allium cepa L. (onion) root tip cells. Genotoxicity studies included measuring mitotic index (MI), chromosomal aberrations (CA) and nuclear abnormalities (NA) in root tip cells following treatment with 25, 50, 75 and 100% (v/v) of effluent. The root tip cells grown in untreated effluent showed a significant decrease in MI from 69% (control) to 32%, 27%, 22% and 11% at 25%, 50%, 75% and 100% effluent concentration, respectively. This indicated that the untreated effluent was highly cytotoxic in nature. Further, root tip cells, when treated with different concentrations of effluent showed various CA and NA including c-mitosis, stickiness, chromosome loss, chromosome break, anaphase bridge, multipolar anaphase, vagrant chromosomes, micronucleated and binucleated cells. The MI observed in root tip cells grown in bacterial treated effluents at similar concentrations (25, 50, 75 and 100% v/v) showed an increase of 33%, 36%, 42% and 66%. CA showed a substantial decrease and in some instances, complete absence of CA was also observed. The findings suggest that S. liquefaciens culture could be a potential bacterial culture for bioremediation of P&P mill effluent, as it is effective in substantial lowering of pollutants load as well as reduces the cytotoxic and genotoxic effects of effluent.


Assuntos
Aberrações Cromossômicas/induzido quimicamente , Enterobacteriaceae/crescimento & desenvolvimento , Papel , Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidade , Purificação da Água/métodos , Biodegradação Ambiental , Enterobacteriaceae/enzimologia , Lignina/análise , Meristema/citologia , Meristema/efeitos dos fármacos , Meristema/genética , Índice Mitótico , Testes de Mutagenicidade/métodos , Cebolas/citologia , Cebolas/efeitos dos fármacos , Cebolas/genética , Peroxidases/metabolismo , Águas Residuárias/análise , Poluentes Químicos da Água/análise
11.
Food Chem ; 199: 870-5, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26776046

RESUMO

In the present communication, a non-covalent fenarimol-imprinted polymer was synthesized by precipitation polymerization technique using methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linker, and azobisisobutyronitrile (AIBN) as an initiator in different porogenic solvent. Binding study of molecularly imprinted and non-imprinted polymer (MIP and NIP) showed that MIP possesses a higher affinity towards this analyte compared to NIP. The binding affinity of MIP was calculated by static and kinetic adsorption study. Further, a MIP based cartridge was designed to use in extraction process, necessary for specific determination and quantification of the fungicide in food matrices. Under the optimum conditions, developed method was found to be linear (R(2)=0.9999-0.9994). Limit of detection (LOD) and limit of quantitation (LOQ) in samples were 0.03-0.06 and 0.12-0.21 µg mL(-1), respectively. The rate of recovery of fenarimol was 91.16-99.52% on MIPs. The validated method of molecularly imprinted solid-phase extraction (MISPE) cartridge was successfully applied to the food matrices and compared with commercial sorbent (RP18 and Oasis HLB). However we feel, this method has promising applications in the routine analysis of food samples in industry.


Assuntos
Impressão Molecular/métodos , Pirimidinas/química , Extração em Fase Sólida/métodos , Qualidade dos Alimentos , Polímeros
12.
J Chromatogr A ; 1377: 27-34, 2015 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-25542703

RESUMO

A new sample preparation technique named as fast agitated directly suspended droplet microextraction (FA-DSDME) was proposed as an improved version of directly suspended droplet microextraction (DSDME) for the extraction and pre-concentration of wide-range organophosphorus pesticides (OPPs) from human blood prior to liquid chromatography tandem mass spectrometric (LC-MS/MS) analysis. In this method, instead of protecting the unwanted rupturing of extraction droplet (organic solvent), it was deliberately splintered into fine droplets by providing automated high-speed agitation to the biphasic extraction system (extraction solvent and sample solution). Fine organic droplets were then recollected into one, not by using a centrifuge machine but just by giving a very slow stirring to the bottom of the extraction system. The present method has surmounted the problem of prolonged extraction time associated with old DSDME. Under optimum extraction conditions, the method showed good sensitivity with low detection limits ranging from 0.0009 to 0.122µgL(-1). Mean recoveries were achieved in the range of 86-109% at three levels of spiking concentration (low, middle and high) from linearity range of individual analyte. Intra-day and inter-day precisions were ≤4.68 and ≤9.57 (%RSD) respectively. Enrichment factor (EF) for each analyte varied from 30 to 132 which prove the ability of this technique to pre-concentrate the extracted analytes up to a good extent. The sample matrices have shown an insignificant influence on method's sensitivity. The proposed method may find immense use in epidemiological, toxicological, regulatory and forensic laboratories.


Assuntos
Análise Química do Sangue/métodos , Compostos Organofosforados/sangue , Praguicidas/sangue , Cromatografia Líquida , Humanos , Limite de Detecção , Compostos Orgânicos/análise , Solventes/química , Espectrometria de Massas em Tandem
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