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1.
Drug Chem Toxicol ; 44(2): 113-123, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30607992

RESUMO

Pharmaceutical residues are present in the environment in mixtures and their adverse effects may also result from interactions that occur between compounds. Studies presented in this work focus on genotoxicity of pharmaceuticals from different therapeutic groups in mixtures and in individual solutions impacted with different environmental conditions assessed using comet assay (alkaline approach). Binary mixtures of pharmaceuticals (in different concentration ratios) and in individual solutions impacted with pH change (range from 5.5 to 8.5) or addition of inorganic ions, were incubated with HT29 cells and after 24 h time period cells were tested for the presence of DNA damage. To estimate whether mixtures act more (synergistic) or less (antagonistic) efficiently Concentrations Addition (CA) and Independent Action (IA) approaches were applied followed by a calculation of the Model Deviation Ratio (MDR) to determine deviation from the predicted values. Addition of inorganic ions mainly reduced their genotoxicity. Diclofenac s. was the most susceptible to potassium, fluoride, and bromide ions. Change of the pH of pharmaceutical solutions had significant impact on genotoxicity of diclofenac s. and fluoxetine h. Among mixtures, more commonly observed interactions were synergistic ones, exactly twenty-five cases (ten pairs containing chloramphenicol or oxytetracycline h.) and ten cases of antagonism (four for pairs containing chloramphenicol or fluoxetine h.). The results obtained indicate that interactions between tested compounds occur frequently and can lead to DNA damage. This topic especially concerning in vitro tests using cells is still rare, however, it should not be neglected.


Assuntos
Dano ao DNA/efeitos dos fármacos , Resíduos de Drogas/toxicidade , Poluentes Ambientais/toxicidade , Mutagênicos/toxicidade , Adenocarcinoma/metabolismo , Neoplasias do Colo/metabolismo , Ensaio Cometa , Sinergismo Farmacológico , Células HT29 , Humanos , Concentração de Íons de Hidrogênio , Testes de Mutagenicidade , Fatores de Tempo
2.
Electrophoresis ; 40(11): 1540-1549, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30838663

RESUMO

In this study, GC-MS- and MEKC-based methods for determination of caffeine (CAF) in preworkout supplements were developed and validated. The proposed protocols utilized minimal sample preparation (simple dilution and syringe filtration). The developed methods achieved satisfactory validation parameters, i.e. good linearity (R2 > 0.9988 and R2 > 0.9985 for GC-MS- and MEKC-based method, respectively), satisfactory intra- and interaccuracy (within 92.6-100.7% for method utilizing GC-MS and 92.1-110.3% for protocol based on MEKC) and precision (CV < 15.9% and CV < 6.3% for GC-MS- and MEKC-based method, respectively) and recovery (within 100.1-100.8% for method utilizing GC-MS and 101.5-106.2% for protocol based on MEKC). The LOD was 0.03 and 3 µg/mL for method utilizing GC-MS and MEKC, respectively. The CAF concentrations determined by GC-MS- and MEKC-based methods were found to be in the range of 8.53-11.23 and 8.20-11.61 µg/mL, respectively. Taking into consideration information on the labels, the investigated supplements were found to contain from 110.0 to 167.3% of the declared CAF content, which confirmed the literature reports on incompatibility of the declared product compositions with real ones. Nevertheless, the consumption of examined supplements as recommended by producers did not lead to exceeding the CAF safe limit of 400 mg per day. Additionally, the MEKC-based method allowed for detection and identification of vitamin B3 and B6 in all of the investigated supplement samples, which demonstrated that MEKC-based protocols may be an appropriate assays for simultaneous determination of CAF and vitamins.


Assuntos
Cafeína/análise , Cromatografia Capilar Eletrocinética Micelar/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Vitaminas/análise , Suplementos Nutricionais/análise , Escore Lod , Niacinamida/análise , Vitamina B 6/análise
3.
Anal Bioanal Chem ; 411(24): 6387-6398, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31321469

RESUMO

Bisphenol A diglycidyl ether (BADGE), bisphenol F diglycydyl ether (BFDGE), and their related compounds are widely used as precursors in production of epoxy resins. The high reactivity of these compounds makes the development of analytical methodologies that ensure appropriate metrological accuracy crucial. Consequently, we aimed to determine whether and to what extent the composition of the solution and storage conditions affect the stability of selected BADGE and BFDGE derivatives. The stabilities of these compounds were studied using liquid chromatography-tandem mass spectrometry with electrospray ionization (HPLC-ESI-MS/MS). The chromatographic method elaborated here has allowed for separation of the analytes in time shorter than 6 min, for both methanol and acetonitrile-based mobile phases. The obtained calibration curves for all analytes were linear in the range tested. The values of limit of detection (LODs) were in the range of 0.91-2.7 ng/mL, while values of limit of quantitation (LOQs) were in the range of 2.7-5.7 ng/mL. The chosen experimental conditions were compared in terms of the content of organic solvent in solution, storage temperature, and time. Our results show that the content of BADGE, BADGE·HCl, BFDGE, three-ring NOGE decreased with increasing water content (> 40% v/v). For BADGE and three-ring NOGE, significant changes in concentration were noted as early as 24 h after the test solutions had been prepared. In addition, a reduction in the storage temperature (4 to - 20 °C) reduced the rate of transformation of the monitored analytes. Our study will increase quality control in future research and may increase the reliability of the obtained results. Graphical abstract.

4.
Sensors (Basel) ; 19(7)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939836

RESUMO

The biogenic amines index of fresh chicken meat samples during refrigerated storage was predicted based on the headspace analysis using an electronic nose equipped with an array of electrochemical sensors. The reference biogenic amines index values were obtained using dispersive liquid⁻liquid microextraction⁻gas chromatography⁻mass spectrometry. A prototype electronic nose with modular construction and a dedicated sample chamber was used to rapidly analyze the volatile fraction of chicken meat samples, with a single measurement time of five minutes. Back-propagation artificial neural network was used to estimate the biogenic amines index of the samples with a determination coefficient of 0.954 based on ten-fold stratified cross-validation. The results indicate that the determination of the biogenic amines index is a good reference method for studies in which the freshness of meat products is assessed based on headspace analysis and fingerprinting, and that the described electronic device can be used to assess poultry meat freshness based on this value with high accuracy.


Assuntos
Aminas Biogênicas/análise , Nariz Eletrônico , Carne/análise , Animais , Aminas Biogênicas/isolamento & purificação , Galinhas , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Microextração em Fase Líquida , Redes Neurais de Computação
5.
J Environ Manage ; 249: 109426, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450196

RESUMO

Sewage sludge, one of the main wastes generated during wastewater treatment, constitutes an important source of emissions of volatile chemical compounds such as volatile aromatic compounds These substances may undergo various changes as a result of operations and unit processes, which affects their concentrations in sewage sludge. An important factor determining the potential hazardousness of volatile organic compounds is the quality of wastewater delivered to wastewater treatment plants and the technical and equipment solutions applied to wastewater. In this study, a rapid and sensitive headspace gas chromatography method, coupled with tandem mass spectrometry using the standard addition method, was developed for the determination of selected volatile aromatic compounds in sewage sludge samples collected at different stages from three wastewater treatment plants located in Poland. This study attempted to assess the relationship between differences in the emissions of representative VACs and the given stage of the technological process within three analysed wastewater treatment plants. Toluene was detected with the highest frequency in analysed samples, at concentrations varying from 0.234 ± 0.035 ng/g of sludge to 28.3*102±3.2*102 ng/g of sludge. The highest concentration levels were determined for p-cresol, with concentrations ranging from 44.0*101±5.6*101 ng/g of sludge (sludge from aerobic chamber, wastewater treatment plant no.2) to 47.7*102±6.9*102 ng/g of sludge (sludge from aerobic chamber, wastewater treatment plant no.1), while the lowest concentration levels were observed for chlorobenzene, with concentrations ranging from 0.1300 ±â€¯0.0030 ng/g of sludge (sludge from anaerobic chamber, wastewater treatment plant no.2), to 0.2606 ±â€¯0.0046 ng/g of sludge (primary sludge, wastewater treatment plant no.1). The repeatability of the method was better than 10%, with accuracy levels in the ranges 89%-108%.Wastewater treatment technologies and residual sludge management in the selected wastewater treatment plantsinfluenced volatile aromatic compounds emission. Furthermore, the diversity of the wastewater quality, depending on the catchment area, is also an important factor determining the differentiation in volatile aromatic compounds emission. The microbial composition of raw wastewater highly influenced not only the treatment effectiveness of wastewater treatment plants but also the production of intermediate products, such as volatile aromatic compounds, which may contribute to odour emissions.


Assuntos
Esgotos , Águas Residuárias , Cromatografia Gasosa-Espectrometria de Massas , Polônia , Eliminação de Resíduos Líquidos
6.
Molecules ; 24(22)2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31752176

RESUMO

The aroma of rice essentially contributes to the quality of rice grains. For some varieties, their aroma properties really drive consumer preferences. In this paper, using a dynamic headspace solid-phase microextraction (HS-SPME) system coupled to a two-dimensional gas chromatography (GC×GC) using a time-of-flight mass spectrometric detector (TOFMS) and multivariate analysis, the volatile compounds of aromatic and non-aromatic rice grains were contrasted to define some chemical markers. Fifty-one volatile compounds were selected for principal component analysis resulting in eight key-marker volatile compounds (i.e., pentanal, hexanal, 2-pentyl-furan, 2,4-nonadienal, pyridine, 1-octen-3-ol and (E)-2-octenal) as responsible for the differences between aromatic and non-aromatic rice varieties. The factors that are most likely to affect the HS-SPME efficiency for the aforementioned key-marker compounds were evaluated using a 2 I I I 5 - 2 fractional factorial design in conjunction with multi-response optimisation. The method precision values, expressed as % of coefficient of variation (CV), were ranging from 1.91% to 26.90% for repeatability (n = 9) and 7.32% to 37.36% for intermediate precision (n = 3 × 3). Furthermore, the method was successfully applied to evaluate the volatile compounds of rice varieties from some Asian countries.


Assuntos
Oryza/química , Compostos Orgânicos Voláteis/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Análise de Componente Principal , Microextração em Fase Sólida
7.
Environ Res ; 165: 294-305, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29777920

RESUMO

The stability of the linings of packaging that is in contact with the goods stored has been of major concern during decades of the development of packaging materials. In this work, an attempt was undertaken to assess the applicability of using two bioassays (Microtox® and XenoScreen YES/YAS) in estimating the stability of packaging (cans, caps, multilayer material) and the impact of their degradation on the toxicity of some simulated media. The assessment of the impact of packaging storage conditions (temperature, disinfection, preservation, extracting and washing solvents) was planned and performed with i) regression modeling of the experimental effects on the ecotoxicity readings, ii) ANOVA and MANOVA estimation of the experimental conditions as significant factors affecting the toxicity results and iii) FTIR analysis of the packages. It is shown that the effects of temperature and extraction solvents could be quantitatively assessed by the agreement between all methods applied. It can be stated that temperature and acidity as well as the alcohol content in the sensitive media have the greatest impact on the toxicity of the extract and thus on the stability of the internal lining and the extractability of xenobiotics.


Assuntos
Embalagem de Produtos , Manejo de Espécimes/métodos , Testes de Toxicidade , Xenobióticos/análise , Análise de Variância , Bioensaio , Modelos Teóricos , Análise Multivariada
8.
J Sep Sci ; 41(20): 3881-3891, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30101517

RESUMO

Ibuprofen is widely used in human and veterinary medicine for the treatment of chronic pain as well as rheumatic and musculoskeletal disorders. However, the analgesic and anti-inflammatory properties of Ibuprofen have contributed to frequent drug abuse in equestrian sports. A sensitive and rapid gas chromatography with tandem mass spectrometry based method with a simple liquid-liquid extraction and derivatization requiring 200 µL volume of sample and 2 mL of extraction solvent for the simultaneous determination of ibuprofen and its metabolites was developed. The proposed procedure was optimized and validated according to the principles for bioanalytical methods. The assay achieved satisfactory validation parameters, namely, recovery (92.2-105%), interday accuracy (92.5-106%), and precision (0.3-4.4%) for all investigated compounds as well as limits of quantification of 50 ng/mL for ibuprofen, 2-hydroxyibuprofen, and carboxyibuprofen, 25 ng/mL for 1-hydroxyibuprofen and 100 ng/mL for 3-hydroxyibuprofen. The applicability of the method was evaluated by the analysis of five real urine samples collected from different horses after drug administration. In view of the low limits of quantification, high selectivity, repeatability, and recovery, the procedure can be utilized for laboratory applications, including the control of ibuprofen abuse in equestrian sports for anti-doping purposes and drug/pharmaceutical mentality investigations.


Assuntos
Ibuprofeno/urina , Animais , Cromatografia Gasosa , Cavalos , Ibuprofeno/metabolismo , Extração Líquido-Líquido , Estrutura Molecular , Espectrometria de Massas em Tandem
9.
Biomed Chromatogr ; 32(3)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29027680

RESUMO

In order to protect human health, it is necessary to biomonitor toxic substances originating from tobacco smoke in biological materials sampled from persons with different exposures to tobacco smoke constituents. Thiocyanate anion is a biomarker of exposure to tobacco smoke components which is characterized by a relatively long half-life in the human body, i.e. 6 days. In this work, we present the results of thiocyanate determinations performed on samples of placenta, meconium, saliva, breast milk, sweat and blood. The placenta samples were subjected to accelerated solvent extraction with water. The thiocyanate concentrations were determined using ion chromatography. The analyzed biological materials were compared with regard to their applicability for biomonitoring toxic substances originating from tobacco smoke. The highest mean concentrations of thiocyanate were observed in the samples of biological materials collected from active smokers.


Assuntos
Tiocianatos/análise , Poluição por Fumaça de Tabaco/análise , Adolescente , Adulto , Idoso , Secreções Corporais/química , Cromatografia por Troca Iônica , Monitoramento Ambiental , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
10.
Ecotoxicol Environ Saf ; 154: 118-126, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29459161

RESUMO

This work analyses the effect of mercury on the condition of cormorants (Phalacrocorax carbo) from an extensive breeding colony in northern Poland, the largest in Europe. A total of 55 birds (44 adults and 11 immature) were obtained. Total mercury (Hg) concentrations were measured in the liver, kidneys, breast muscles, heart, gullet (oesophagus), stomach, intestines, trachea, lungs and eyeballs. The total body mass (TBM) and empty body mass (EBM) were measured, and the body parts taken for analysis were weighed. The relative mass of the tissues and the L/K index were expressed as percentages. Based on the L/K index the birds were divided into three condition classes: (A) very good, (B) good and (C) moderate. The mean TBM and EBM in these cormorants were 2286 and 2184 g respectively. The greatest contributions to EBM were from the breast muscles (~11%), liver (3.7%) and intestines (3.0%). The stomach, gullet, lungs, heart and kidneys made up from ~1.0-2.8% EBM, and the trachea and eyeballs < 0.4%. 31 of the 55 birds analysed were allocated to class B; mean Hg levels in them were the highest in the kidneys, liver, lungs and muscles (18.3, 9.78, 2.70, 1.86 µg/g dw respectively); they were ≤ 1 µg/g in the other tissues. In ecotoxicology it is assumed that a hepatic concentration > 16.7 µg Hg/g dw can lead to adverse effects in the reproduction of non-marine birds. In the light of the present results, the reproductive parameters of the cormorants from the colony in northern Poland, though mostly in good or very good condition, may be depressed as a result of elevated Hg levels in their body tissues.


Assuntos
Aves/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Poluentes Ambientais/toxicidade , Mercúrio/análise , Animais , Peso Corporal/efeitos dos fármacos , Rim/química , Rim/efeitos dos fármacos , Fígado/química , Fígado/efeitos dos fármacos , Pulmão/química , Pulmão/efeitos dos fármacos , Músculos/química , Músculos/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Polônia
11.
Ecotoxicol Environ Saf ; 147: 292-298, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28850812

RESUMO

The study presents the result of the application of chemometric tools for selection of physicochemical parameters of solvents for predicting missing variables - bioconcentration factors, water-octanol and octanol-air partitioning constants. EPI Suite software was successfully applied to predict missing values for solvents commonly considered as "green". Values for logBCF, logKOW and logKOA were modelled for 43 rather nonpolar solvents and 69 polar ones. Application of multivariate statistics was also proved to be useful in the assessment of the obtained modelling results. The presented approach can be one of the first steps and support tools in the assessment of chemicals in terms of their greenness.


Assuntos
Química Verde/métodos , Modelos Químicos , Solventes/química , Solventes/classificação , Fenômenos Químicos , Análise por Conglomerados , Química Verde/estatística & dados numéricos , Análise Multivariada , Octanóis/química , Água/química
12.
Ecotoxicol Environ Saf ; 164: 317-324, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30125778

RESUMO

Topsoil and grass samples from 14 sites located in different distances from three copper mining factories and a copper smelter were collected in Srednogorie, Bulgaria. The paper discusses results of studies on the mobility of potentially toxic elements (As, Cd, Cr, Cu, Mn, Ni, Pb, Zn) from contaminated soils to wild grass Cynodon dactylon in terms of transfer (TF: soil to plant) and phytoavailability (PF: EDTA (ethylenediaminetetraacetic acid)-soluble to plant) factors. Soils located close to mine and smelter factories were heavily contaminated by As and Cu reaching levels up to 500 mg/kg and 2400 mg/kg, respectively for As and Cu. At seven sites arsenic and copper in grass were over the normal levels (1 mg/kg As; 20 mg/kg Cu). The content of Cu in grass averaged 63 mg/kg exceeding the maximum allowable for sheep. Relationship between PF and TF values was found for As, Cd, Cu, Ni, Pb, Zn but not for Mn and Cr. To some extent the soil pH, TOM (total organic matter) and CaCO3 content are related to the phytoavailability of As, Cd and Cu since for Zn and Pb this relation is attributed to Al- and Fe-content of soil. Statistically significant correlation coefficients were determined between the EDTA-soluble fraction of soil and content in grass in the case of As, Cd, Cr, Cu, Mn and Pb indicating the suitability of the short procedure for phytoavailability studies of those elements. The application of hierarchical cluster analysis and self-organizing maps of Kohonen made it possible to reveal specific hidden relationships between the soil variables and transfer factors as well as between the sampling locations. This additional information helps in more detailed interpretation of phytoavailability and transfer processes in the region of interest. The novelty in this study is achieved by careful consideration of the possibility of using EDTA extracts of the toxic metals in investigating of the phytoavailability and transfer processes soil/plant. Additionally, chemometric expertise used makes it possible to differentiate the behavior of each toxic metal in the processes studied. The combination of easy option for rapid extraction and intelligent data analysis gives a new perspective for contributions in explanation of the complex interactions between soils and plants when assessing pollution events in a certain environment.


Assuntos
Poluição Ambiental/análise , Poaceae , Poluentes do Solo/análise , Solo/química , Animais , Disponibilidade Biológica , Bulgária , Análise por Conglomerados , Cobre/análise , Ácido Edético , Monitoramento Ambiental , Geografia , Concentração de Íons de Hidrogênio , Metais Pesados/análise , Mineração , Plantas , Ovinos , Oligoelementos/análise
13.
Ecotoxicol Environ Saf ; 160: 282-289, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29857233

RESUMO

The development of new methods for identifying a broad spectrum of analytes, as well as highly selective tools to provide the most accurate information regarding the processes and relationships in the world, has been an area of interest for researchers for many years. The information obtained with these tools provides valuable data to complement existing knowledge but, above all, to identify and determine previously unknown hazards. Recently, attention has been paid to the migration of xenobiotics from the surfaces of various everyday objects and the resulting impacts on human health. Since children are among those most vulnerable to health consequences, one of the main subjects of interest is the migration of low-molecular-weight compounds from toys and products intended for children. This migration has become a stimulus for research aimed at determining the degree of release of compounds from popular commercially available chocolate/toy sets. One of main objectives of this research was to determine the impact of time on the ecotoxicity (with Vibrio fischeri bioluminescent bacteria) of extracts of products intended for children and to assess the correlation with total volatile organic compound emissions using basic chemometric methods. The studies on endocrine potential (with XenoScreen YES/YAS) of the extracts and showed that compounds released from the studied objects (including packaging foils, plastic capsules storing toys, most of toys studied and all chocolate samples) exhibit mostly androgenic antagonistic behavior while using artificial saliva as extraction medium increased the impact observed. The impact of time in most cases was positive one and increased with prolonging extraction time. The small-scale stationary environmental test chambers - µ-CTE™ 250 system was employed to perform the studies aimed at determining the profile of total volatile organic compounds (TVOCs) emissions. Due to this it was possible to state that objects from which the greatest amounts of contaminants are released are plastic containers (with emission rate falling down from 3273 to 2280 ng/g of material at 6 h of conditioning in elevated temperature).


Assuntos
Chocolate/análise , Disruptores Endócrinos/análise , Jogos e Brinquedos , Compostos Orgânicos Voláteis/análise , Aliivibrio fischeri/efeitos dos fármacos , Criança , Disruptores Endócrinos/toxicidade , Contaminação de Alimentos , Humanos , Plásticos/química , Saliva Artificial/química , Compostos Orgânicos Voláteis/toxicidade , Xenobióticos/química , Xenobióticos/toxicidade
14.
Sensors (Basel) ; 18(11)2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30441858

RESUMO

The quartz-crystal microbalance is a sensitive and universal tool for measuring concentrations of various gases in the air. Biochemical functionalization of the QCM electrode allows a label-free detection of specific molecular interactions with high sensitivity and specificity. In addition, it enables a real-time determination of its kinetic rates and affinity constants. This makes QCM a versatile bioanalytical screening tool for various applications, with surface modifications ranging from the detection of single molecular monolayers to whole cells. Various types of biomaterials, including peptides mapping the binding sites of olfactory receptors, can be deposited as a sensitive element on the surface of the electrodes. One of key ways to ensure the sensitivity and accuracy of the sensor is provided by application of an optimal and repeatable method of immobilization. Therefore, effective sensors operation requires development of an optimal method of deposition. This paper reviews popular techniques (drop-casting, spin-coating, dip-coating) for coating peptides on piezoelectric crystals surface. Peptide (LEKKKKDC-NH2) derived from an aldehyde binding site in the HarmOBP7 protein was synthesized and used as a sensing material for the biosensor. The degree of deposition of the sensitive layer was monitoring by variations in the sensors frequency. The highest mass threshold for QCM measurements for peptides was approximately 16.43 µg·mm-2 for spin coating method. Developed sensor exhibited repeatable response to acetaldehyde. Moreover, responses to toluene was observed to evaluate sensors specificity. Calibration curves of the three sensors showed good determination coefficients (R² > 0.99) for drop casting and dip coating and 0.97 for the spin-coating method. Sensors sensitivity vs. acetaldehyde were significantly higher for the dip-coating and drop-casting methods and lower for spin-coating one.


Assuntos
Técnicas Biossensoriais , Gases/isolamento & purificação , Peptídeos/química , Técnicas de Microbalança de Cristal de Quartzo , Aldeídos/química , Sítios de Ligação , Eletrodos , Gases/toxicidade , Cinética , Ligação Proteica , Propriedades de Superfície
15.
Sensors (Basel) ; 18(2)2018 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-29419798

RESUMO

This paper presents application of an electronic nose prototype comprised of eight sensors, five TGS-type sensors, two electrochemical sensors and one PID-type sensor, to identify odour interaction phenomenon in two-, three-, four- and five-component odorous mixtures. Typical chemical compounds, such as toluene, acetone, triethylamine, α-pinene and n-butanol, present near municipal landfills and sewage treatment plants were subjected to investigation. Evaluation of predicted odour intensity and hedonic tone was performed with selected artificial neural network structures with the activation functions tanh and Leaky rectified linear units (Leaky ReLUs) with the parameter a = 0.03 . Correctness of identification of odour interactions in the odorous mixtures was determined based on the results obtained with the electronic nose instrument and non-linear data analysis. This value (average) was at the level of 88% in the case of odour intensity, whereas the average was at the level of 74% in the case of hedonic tone. In both cases, correctness of identification depended on the number of components present in the odorous mixture.

16.
J Environ Manage ; 213: 417-424, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29505997

RESUMO

Odour nuisance poses a serious problem in many urban areas, yet its evaluation and mitigation is often omitted in the urban planning process. By identifying its range and spatio-temporal variations, it could be taken into consideration by planners in urban development strategies and land use decisions. The aim of the study was to present the application of odour evaluation techniques in the improvement of the quality of life in the built environment. The problem of odours is discussed in regard to human health, social aspects and current practices in the management of spatial development. The application possibilities of field olfactometry are demonstrated based on a case study of a municipal landfill which is a major source of odour nuisance for the adjacent areas. The results of odour nuisance measurements were field olfactometry combined with topographical and meteorological data. Using dispersion modelling (non-steady-state Lagrangian Gaussian puff model CALPUFF with dedicated meteorological pre-processor CALMET) it was possible to calculate odour concentrations and to place the measured odour concentrations in a specific spatial context. The obtained results were juxtaposed with local development strategies and discussed in the context of environmental-based planning. We suggest that odour evaluation and dispersion modelling are valid tools in managing the dynamics of urban growth.


Assuntos
Planejamento de Cidades , Monitoramento Ambiental , Odorantes , Saúde Ambiental , Humanos , Distribuição Normal , Qualidade de Vida
17.
Molecules ; 23(10)2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30304845

RESUMO

Developed and validated analytical methods for the determination of a wide spectrum of pesticide residues in honey and honeybee samples after the modification of QuEChERS extraction in combination with gas chromatography⁻tandem quadrupole mass spectrometry (GC-MS/MS) and liquid chromatography⁻tandem quadrupole mass spectrometry (LC-MS/MS) were discussed and compared. The developed methods were evaluated regarding the utilized equipment and reagents using Eco-Scale and compared in terms of extraction time, accuracy, precision, sensitivity and versatility, with similar procedures. The results proved that the QuEChERS protocol in combination with LC and GC techniques fulfills the requirements of green analytical chemistry, so it can be used as a tool in environmental monitoring. The recovery was 85⁻116% for honey and 85.5⁻103.5% for honeybee samples. The developed methods were successfully applied in monitoring real samples collected from three districts of Pomerania in Poland. Analysis of real samples revealed the presence of the following pesticides: bifenthrin, fenpyroximate, methidathione, spinosad, thiamethoxam, triazophos, metconazole and cypermethrin at levels higher than the MRLs established by the EU.


Assuntos
Abelhas , Mel/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Animais , Cromatografia Líquida , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
18.
Molecules ; 23(5)2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29747446

RESUMO

A survey of biogenic amine (BA) profiles in opened wine bottles has been established to monitor the level of biogenic amines (BAs) in opened bottles against time and other conditions. Bottles of red and white wine were submitted to different temperatures, stopper type (screw cap, cork), and use of vacuum devices. A total of six wines made from a variety of grapes were obtained from vineyards from regions across Poland. Dispersive liquid-liquid microextraction-gas chromatography-mass spectrometry (DLLME-GC-MS) procedure for BAs determination was validated and applied for wine sample analysis. The total content of BAs from the set of immediately opened wine samples ranged from 442 to 929 µg/L for white wines, and 669 to 2244 µg/L for red wines. The most abundant BAs in the analysed wines were histamine and putrescine. Considering the commercial availability of the analysed wines, there was no relationship between the presence of BAs in a given wine and their availability on the market. However, it was observed and confirmed by chemometric analysis that the different storage conditions employed in this experiment affect not only the BAs profile, but also the pH.


Assuntos
Aminas Biogênicas/análise , Preservação Biológica , Vinho/análise , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Padrões de Referência , Fatores de Tempo
19.
Molecules ; 23(11)2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30400672

RESUMO

Knowledge about the metal content of wine is very important, for many reasons. Depending on the element, its quantity varies in wine from ng/L to mg/L. Despite the fact that metals are not directly connected to the taste and aroma of the wine, their content should be determined and controlled, because excess is undesirable, and in some cases prohibited, due to potential toxicity. Several analytical procedures for metal determination are applied. However, due to sensitivity, low limit of detection and speed of analysis, inductively coupled plasma-mass spectrometry (ICP-MS) is one of the most frequently used techniques. The aim of this study was to reveal specific relationships between the wine samples or between the chemical variables in order to classify the wines according to their metal content by application of chemometric analysis. For metals content determination, two techniques, ICP-MS and inductively coupled plasma-optical emission spectrometry (ICP-OES), were applied. Data obtained showed that none of the wine samples surpassed the toxic levels reported for metals in the literature, thus, these wines appeared to be safe as regards the risk associated with the potentially toxic metals intake. However, specific correlations between metals and specific aspects of the wines themselves have been found.


Assuntos
Espectrometria de Massas , Metais/análise , Vinho/análise
20.
Molecules ; 23(12)2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30563287

RESUMO

Bisphenol A (BPA) is one of the most popular and commonly used plasticizer in the industry. Over the past decade, new chemicals that belong to the bisphenol group have increasingly been used in industrial applications as alternatives to BPA. Nevertheless, information on the combined effects of bisphenol (BP) analogues is insufficient. Therefore, our current study aimed to find the biological response modulations induced by the binary mixtures of BP compounds. We determined the toxicity levels in Microtox and XenoScreen YES/YAS assays for several BP analogs alone, and for their binary mixtures. The results obtained constituted the database for chemometric intelligent data analysis to evaluate the possible interactions occurring in the mixtures. Several chemometric/biophysical models have been used (concentration addition-CA, independent action-IA and polynomial regression calculations) to realize this aim. The best fitting was found for the IA model and even in this description strong evidence for synergistic behaviors (modes of action) of some bisphenol analogue mixtures was demonstrated. Bisphenols A, S, F and FL were proven to be of significant endocrine threat (with respect to XenoScreen YES/YAS assay); thus, their presence in mixtures (including presence in tissues of living organisms) should be most strictly monitored and reported.


Assuntos
Compostos Benzidrílicos , Poluentes Ambientais , Fenóis , Compostos Benzidrílicos/análise , Compostos Benzidrílicos/toxicidade , Bioensaio , Ecotoxicologia , Poluentes Ambientais/análise , Poluentes Ambientais/toxicidade , Modelos Químicos , Fenóis/análise , Fenóis/toxicidade
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