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1.
Mymensingh Med J ; 29(1): 183-186, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31915356

RESUMO

Diabetes mellitus (DM) is the leading cause of death worldwide, responsible for one third of death, higher glycemic status and diabetes related complication are the most common cause. Low level of chromium (Cr) one of the major contributors higher glycemic status and increased the risk of diabetes related complication in type 2 diabetes mellitus. This study was aimed to find out the relationship between glycemic status and serum chromium level with type 2 diabetes mellitus. This cross sectional study was conducted in the Department of Physiology, Dhaka Medical College, Dhaka, Bangladesh from July 2014 to June 2015. Fifty type 2 diabetic subjects with age ranging from 40 to 55 years were study group and fifty ages, BMI matched healthy subjects were control group. Patients were selected from Bangladesh Institute of Research for Diabetic Endocrine and Metabolic Disorders (BIRDEM) General Hospital, Dhaka, Bangladesh. HbA1c, FSG levels were estimated in the laboratory of the Department of Biochemistry, BIRDEM General Hospital, Dhaka. Serum Cr level was estimated by flame atomic absorption spectrophotometry. For statistical analysis unpaired Student's 't' test was performed. In this study, mean serum chromium level was significantly (P<0.001) lower in diabetic patients than that of control group. On correlation analysis, serum Cr level showed significant negative correlation with FSG and HbA1C levels in type 2 diabetic patients. The study reflected that serum Cr level was reduced in DM which was higher with glycemic status of this disease. Categorization of patients with type 2 DM on the basis of low serum Cr level and high FSG and HbA1c level will be helpful for risk of diabetic complications.


Assuntos
Glicemia/análise , Cromo/sangue , Diabetes Mellitus Tipo 2/sangue , Hemoglobina A Glicada/metabolismo , Adulto , Bangladesh , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectrofotometria Atômica
2.
Crit Rev Anal Chem ; 50(1): 78-89, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30777442

RESUMO

The separation and purification techniques of chelates can improve the accuracy of detecting results of the chelation rate. As a quantitative indicator of metal ion chelates, the chelation rate can not only reflect the completion of chelation but also determine the amount of metal ions in different forms. The determination of chelation rate can help to determine the suitable chelating reaction conditions, make theoretical basis for the fertilizer efficiency, analyze the stability of chelating fertilizers and study the action mechanism of trace elements. In our study, the methods of separation free metal ions from mixture were reviewed first, including gel filtration chromatography, organic solvent precipitation, ion exchange chromatography, membrane separation and high performance liquid chromatography. Then, the qualitative analysis methods of chelates were introduced briefly, including chemical identification, infrared spectroscopy, ultraviolet spectroscopy. A detailed overview of the quantitative determination methods of chelates were also shown, such as ethylenediaminetetraacetic acid titration, chemical titration, atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry, inductively coupled plasma mass spectrometry, spectrophotometric, chemical modified electrode. In addition, the merits and demerits of chelated rate determination methods of various determination methods were analyzed, and summarized the applicability of various methods, which provided a theoretical basis for optimizing chelating process, characterizing the structure of chelates and analyzing the mechanism of chelating fertilizer. The current methods of measuring chelation rate were also summarized and prospected.


Assuntos
Quelantes/química , Complexos de Coordenação/química , Metais/química , Cromatografia Líquida , Cinética , Espectrometria de Massas , Solventes/química , Espectrofotometria Atômica , Oligoelementos/análise
3.
Food Chem ; 306: 125638, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606632

RESUMO

A green and innovative eutectic solvent based extraction method was proposed for the determination of trace level vanadium in water and food samples by graphite furnace atomic absorption spectrometry. In this extraction technique magnetic stirrer was used for preparation of eutectic solvent by mixing of zinc chloride and acetamide at different molar ratios. Extraction capability of eutectic solvent was increased by adding a non ionic surfactant (Triton X-114) to enhanced phase transfer ratio, to significantly increase the recovery of hydrophobic complex of vanadium with ammonium pyrrolidine dithiocarbamate. A multivariate technique was applied to evaluate the important extraction parameters, which plays important role for optimum recovery of the targeted analyte by proposed extraction method. Multivariate techniques such as (factorial design and central composite design) were applied to screening out the most significant extraction parameters and optimized them. Under optimized extraction conditions, limit of detection and enhancement factor were found to be 0.01 µg L-1 and 64.6, respectively. The relative standard deviation for the determination of trace level vanadium at 0.32 µg L-1 concentration, was achieved to be <3.0% (n = 10). Validity and accuracy of the proposed extraction method was checked by analysis of certified reference materials of Canadian lake water and tomato leaves with % age recovery >98%. The eutectic solvent extraction method was successfully applied for the determination of the trace level vanadium in real water samples of different sources and acid digested food samples, collected from different locations of Tokat city, Turkey.


Assuntos
Alimentos , Vanádio/análise , Água/química , Canadá , Análise de Alimentos , Grafite/química , Magnetismo , Solventes/química , Espectrofotometria Atômica/métodos
4.
Food Chem ; 309: 125460, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31732251

RESUMO

The high concentrations of mercury found in Amazon have been intensively studied by the scientific community in the last decades. These mercurial species bind preferentially to proteins. Therefore, this work proposal sought to obtain the fractionation, identification and study of mercury - bound proteins present in samples of muscular and hepatic tissue from fish collected in the reservoir of the Jirau Hydroelectric Power Plant - on the Madeira River. Two-dimensional electrophoresis (2D-PAGE) for protein fractionation, graphite furnace atomic absorption spectrometry (GFAAS) for the quantification of mercury and Mass Spectrometry (ESI-MS/MS) were used for the identification of proteins. Concluding the work with analysis of graphics from the Blast2go program. Two mercury - bound proteins were identified as triosephosphate isomerase A and Protein FAM45A. The data generated by the bioinformatics programs confirm the tendency of these proteins to be linked to mercury and elucity the possibles existing physiological and cellular interactions.


Assuntos
Peixes , Fígado/química , Mercúrio/análise , Músculo Esquelético/química , Animais , Brasil , Eletroforese em Gel Bidimensional , Rios/química , Espectrofotometria Atômica , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise
5.
Food Chem ; 309: 125754, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31734006

RESUMO

The present work illustrates the potential of laser-induced breakdown spectroscopy (LIBS) for the direct analysis of liquid food products. The aim of the experiment was to predict calcium content in ready-to-feed infant formula. The analysis was performed by a LIBS system coupled to a liquid sample chamber with a rotatory wheel that presents the liquid to the laser beam as a thin film. Multivariate analysis with partial least squares regression (PLSR) was performed to correlate LIBS spectral data to reference calcium contents. The obtained PLSR model exhibited a good fit and linearity, as indicated by the coefficients of determination for calibration (Rc2) and cross-validation (Rcv2), with values of 0.96 and 0.89, respectively. The robustness of the calibration model was assessed by external validation showing a root-mean-square error of prediction of 6.45 mg 100 mL-1. These results demonstrated the potential of LIBS for real-time analysis of liquid food products.


Assuntos
Cálcio/análise , Fórmulas Infantis/análise , Lasers de Estado Sólido , Espectrofotometria Atômica/métodos , Cálcio/normas , Calibragem , Humanos , Lactente , Análise dos Mínimos Quadrados , Modelos Lineares , Reprodutibilidade dos Testes , Espectrofotometria Atômica/normas
6.
Chemosphere ; 239: 124788, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31521935

RESUMO

Digestion of biomass derived carbonaceous materials such as biochar (BC) can be challenging due to their high chemical recalcitrance and vast variations in composition. Reports on the development of specific sample digestion methods for such materials remain inadequate and thus require considerable attention. Nine different carbonaceous materials; slow-pyrolyzed tea-waste and king coconut BC produced at 300 °C, 500 °C and 700 °C, sludge waste BC produced at 700 °C, wet fast-pyrolyzed Douglas-Fir BC and steam activated coconut shell BC have been tested to evaluate a relatively fast and convenient open-vessel digestion method using seven digestion reagents including nitric acid (NA), fuming nitric acid (FNA), sulfuric acid (SA), NA/SA, FNA/SA, NA/H2O2 and SA/H2O2 mixtures. From the tested digestion reagents, SA/H2O2 mixture dissolved low temperature produced BC (LTBC) within 2 h with occasional shaking and no external heating. Except peroxide mixtures, the other reagents were used to evaluate microwave digestion (MWD) efficiency. Nitric acid mixture was capable of only completely digesting LTBC in the MWD procedure whereas FNA, NA/SA and FNA/SA mixtures resulted in the successful dissolution of all tested carbonaceous materials. Amongst them, FNA provided the least matrix effect in the quantification of the four metals tested using flame atomic absorption spectrophotometry. Tested recoveries for FNA were satisfactory as well. It was concluded that FNA is a preferable reagent for microwave digestion of BC.


Assuntos
Carvão Vegetal/química , Resíduos , Cocos , Indústria de Laticínios , Peróxido de Hidrogênio , Metais/análise , Micro-Ondas , Ácido Nítrico/química , Pirólise , Esgotos , Espectrofotometria Atômica/métodos , Ácidos Sulfúricos/química
7.
Food Chem ; 305: 125456, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525594

RESUMO

This work developed a new technique and an application of an existing approach to determine sodium in food sauces, involving enthalpimetric reactions in the infrared. Infrared Thermometric Titration (TT-IR) was utilized, with simple analyzers and low-cost measurement instruments for the acquisition of the surface temperature generated in the sodium precipitation reaction and development of software for the acquisition and processing of data using Raspberry Pi. The sodium was also quantified by Thermal Infrared Enthalpimetry (TIE), a recently developed technique. The rapid and simple quantification of sodium by the TT-IR and TIE showed the possibility of a selective reaction for sodium, using aluminum nitrate, potassium and ammonium fluoride in an acid medium, with reduction of the reagents and without the digestion step in the sample preparation. The results acquired through TT-IR and TIE corroborated the Flame Atomic Emission Spectrometry (FAES) with 96 to 103% and 95 to 102%, respectively.


Assuntos
Análise de Alimentos/métodos , Raios Infravermelhos , Sódio/análise , Produtos Vegetais/análise , Compostos de Alumínio/química , Limite de Detecção , Nitratos/química , Sódio/química , Espectrofotometria Atômica , Temperatura Ambiente , Termometria/métodos
8.
Food Chem ; 308: 125647, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31648088

RESUMO

An analyser was constructed on the basis of on-line connection of capillary electrophoresis over a short separation path with continuous mini-dialysis sample collection. The developed instrument was employed for simultaneous determination of the majority minerals K+, Ca2+, Na+ and Mg2+ (and possibly NH4+ ions) in commercially available unflavoured yoghurts. The cations are released from the organic structures by digestion with boiling 6 mol/L HCl. They were separated from residues of the organic matrix by a dialysis probe and were transferred to a stream of water. From the continuous stream, the dialysate was injected into the separation capillary through a flow-gating interface. Within the reliability interval, the determined total mineral content was equal to their contents stated on the yoghurt labels and the content determined by flame atomic absorption spectrometry and complexometric titration. The relative standard deviation of the electrophoretic determination is mostly about 5%.


Assuntos
Iogurte/análise , Cátions/química , Diálise , Eletroforese Capilar/métodos , Reprodutibilidade dos Testes , Espectrofotometria Atômica , Fatores de Tempo , Água/análise
9.
Ecotoxicol Environ Saf ; 188: 109896, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31704329

RESUMO

Blood is the transmission medium for metal contaminants to and from bodily organs; as such, it can provide useful and reliable information about their bio-kinetics as they're distributed throughout the body. Metals can interact with endogenous proteins present in the blood, and these metal-protein complexes often dictate the fates of the introduced metals. The aim of this study was to investigate cadmium-binding protein characteristics in normal human plasma. Cadmium-binding plasma proteins in two different groups: normal human plasma (n = 29), and normal paired maternal and fetal umbilical cord plasmas (n = 3), were analyzed. In order to detect cadmium-binding plasma proteins present in low concentrations, blood plasma samples were first depleted of their two most abundant proteins - albumin and immunoglobulin G. Both the crude and depleted plasma samples were analyzed using column gel electrophoresis in conjunction with Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). One cadmium-binding protein was detected in 11 of 29 normal plasma samples and all three paired maternal and cord plasma samples. This protein was further identified as apolipoprotein A-I by high-resolution mass spectrometry. To the best of our knowledge, this is the first study to reveal cadmium-binding proteins in real human blood plasma, which is extremely critical to our understanding of cadmium transportation and accumulation in human blood.


Assuntos
Apolipoproteína A-I/sangue , Cádmio/sangue , Poluentes Ambientais/sangue , Sangue Fetal/química , Metalotioneína/sangue , Feminino , Humanos , Limite de Detecção , Espectrometria de Massas , Espectrofotometria Atômica
10.
Food Chem ; 305: 125452, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514050

RESUMO

Flakes are an assortment of grain products mainly consumed for breakfast. Most of them are important source of nutrients including minerals. Twenty commercial flakes from different raw materials were included in this study, both gluten (barley, rye, spelt, wheat) and gluten-free (amaranth, buckwheat, corn, quinoa, millet, oat, rice, teff). The content of minerals (Ca, Fe, K, Mg, Mn, Na and Zn), dietary fiber (total, soluble and insoluble), tannins and phytates was determined. Moreover, the phytates:mineral molar ratios and the percentage of the realization of mineral requirements were calculated. For the first time the mineral bioavailability from the gluten and gluten-free flakes was evaluated and compared. It allowed indicating amaranth and teff products as flakes with the highest impact on the realization of daily requirements for minerals, especially for magnesium and iron. This aspect is particularly important for people on a gluten-free diet who often represent mineral deficiencies.


Assuntos
Fibras na Dieta/análise , Minerais/análise , Ácido Fítico/análise , Taninos/análise , Disponibilidade Biológica , Chenopodium quinoa/química , Chenopodium quinoa/metabolismo , Grão Comestível/química , Fagopyrum/química , Fagopyrum/metabolismo , Glutens/metabolismo , Hordeum/química , Hordeum/metabolismo , Milhetes/química , Milhetes/metabolismo , Espectrofotometria Atômica , Triticum/química , Triticum/metabolismo
11.
Food Chem ; 302: 125336, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419772

RESUMO

This study reports a stepwise optimization of switchable liquid-liquid microextraction (SLLME) for cobalt determination by flame atomic absorption spectrometry (FAAS) coupled with a slotted quartz tube (SQT). The main purpose of this study was to develop an accurate and sensitive analytical method for cobalt. Extraction method was used to separate and preconcentrate cobalt from sage tea and vitamin B12 samples after complexing with a Schiff base ligand. 107.7 folds enhancement in detection power under the optimum conditions was recorded with respect to direct FAAS. This enhancement correlated to 3.1 µg/L limit of detection and 10 µg/L limit of quantification. The SLLME-SQT-FAAS method was linear over a broad concentration range and low %RSD values established high precision for the method. Appreciable percent recovery results (94-108%) obtained from spiked sage sample and from cobalamin also validated the accuracy of the method.


Assuntos
Cobalto/análise , Microextração em Fase Líquida/métodos , Espectrofotometria Atômica/métodos , Chás de Ervas/análise , Vitamina B 12/análise , Limite de Detecção , Quartzo , Reprodutibilidade dos Testes , Salvia officinalis/química , Bases de Schiff/química , Espectrofotometria Atômica/instrumentação , Vitamina B 12/química
12.
Food Chem ; 303: 125396, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446365

RESUMO

This study describes the determination of lead at trace levels by slotted quartz tube flame atomic absorption spectrophotometry (SQT-FAAS) after preconcentration by the help of stearic acid coated magnetic nanoparticle (SAC-MNPs) based sonication assisted dispersive solid phase extraction (SA-DSPE). SAC-MNPs were used due to their easy separation advantages by the application of external magnetic field. All extraction parameters were optimized by response surface methodology based experimental design. The experimented data was evaluated by the analysis of variance. Under the optimum conditions, about 31 folds enhancement in detection power was obtained over the conventional FAAS. The recovery results obtained for samples spiked at 60 and 120 ng mL-1 were 106.6 and 102.6%, respectively, validating the method as accurate and applicable to the red pepper matrix. The percent relative standard deviations of the results were under 5.0% even at low concentrations that established high precision for replicate extractions and instrumental readings.


Assuntos
Capsicum/química , Chumbo/análise , Chumbo/isolamento & purificação , Microextração em Fase Líquida/métodos , Magnetismo/métodos , Extração em Fase Sólida/métodos , Espectrofotometria Atômica/métodos , Contaminação de Alimentos/análise , Frutas/química , Magnetismo/instrumentação , Nanopartículas de Magnetita/química , Quartzo/química , Sensibilidade e Especificidade , Sonicação , Ácidos Esteáricos/química
13.
Prensa méd. argent ; 105(11): 849-851, dic2019. tab
Artigo em Inglês | LILACS, BINACIS | ID: biblio-1050068

RESUMO

This study focuses on the heavy metals concentrations (Fe, Cu, Zn, Pb, and Cd) in certain common milk species are collected from Iraqi markets using Flame Atomic Absorption Spectrophotometer-6300 AA, Shimadzu, Japan, respectively. This study shows the pollution in the environment obtained by heavy metals. The results showed that Cr, Cd, Cu, Zn, and Fe were varying according to the order: Zn>Fe>Cr>Cd>Cu. levels of heavy metals were 0.610(Cr), 0.125(Cd), 0.052(Cu), and 6.902(Zn), and 0.759(Fe). All the heavy metals were observed within maximum limit in milk. Overall, the number of analyzed heavy metals and sample size were limited in present study. Keywords: Heavy metals; Milk; Najaf; Flame atomic absorption; Spectrophotometer This study focuses on the heavy metals concentrations (Fe, Cu, Zn, Pb, and Cd) in certain common milk species are collected from Iraqi markets using Flame Atomic Absorption Spectrophotometer-6300 AA, Shimadzu, Japan, respectively. This study shows the pollution in the environment obtained by heavy metals. The results showed that Cr, Cd, Cu, Zn, and Fe were varying according to the order: Zn>Fe>Cr>Cd>Cu. levels of heavy metals were 0.610(Cr), 0.125(Cd), 0.052(Cu), and 6.902(Zn), and 0.759(Fe). All the heavy metals were observed within maximum limit in milk. Overall, the number of analyzed heavy metals and sample size were limited in present study


Assuntos
Espectrofotometria Atômica , Espectrofotômetros de Chama , Metais Pesados/toxicidade , Leite
14.
Environ Monit Assess ; 191(11): 692, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667640

RESUMO

In this study, a rapid and effective dispersive solid-phase microextraction (d-SPME) method was developed to preconcentrate Pd from aqueous extract of soil samples by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS). The unique properties of magnetic nanoparticles (MNPs) were used to directly isolate Pd from the sample solutions without the need for complexation. Significant parameters of the extraction method such as magnetic nanoparticle type and amount, pH and amount of buffer solution, amount of eluent, and mixing type and period were optimized together with other instrumental parameters to boost the absorbance signal of Pd. An SQT was fitted onto the burner head to boost the interaction between Pd atoms and hollow cathode lamp radiation to enhance absorbance signals. The limit of detection (LOD) and limit of quantification (LOQ) values for Pd determined (d-SPME-MNP-SQT-FAAS) were 6.4 and 21.4 ng/mL, respectively. The percentage relative standard deviation of the developed method was calculated as 6.6%. The method was applied to soil samples taken from the campus area and spiked recovery experiments were performed to evaluate the method's accuracy/applicability. Satisfactory percent recovery results (90-101%) were obtained for different spiked concentrations and this proved the accuracy/applicability of the method.


Assuntos
Paládio/análise , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Limite de Detecção , Microextração em Fase Líquida/métodos , Magnetismo , Nanopartículas de Magnetita , Quartzo/química , Solo , Microextração em Fase Sólida , Espectrofotometria Atômica/métodos , Água/análise
15.
Environ Pollut ; 255(Pt 2): 113305, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31669954

RESUMO

In early nineteen century, a gas field was operational in southern part of Sindh, Pakistan for power production. The plant was completely un-operational for last three decades, whereas all wastage and raw materials are still dumped there, which might be the source to contaminate the ground water. The most of the workers population still living in different villages nearby the gas field. In present study, evaluated the undesirable effects of the toxic metals (lead and cadmium) via consuming groundwater for drinking and other domestic purpose especially in children of ≤5.0 years. For comparative purpose groundwater of nonindustrial area (nonexposed) was also analysed and their impact on age matched children was carried out. Biological samples (scalp hair and blood) were collected from children of exposed and nonexposed areas. The Cd and Pb in scalp hair and blood samples were carried out by graphite furnace atomic absorption spectrometry. Whereas, Cd and Pb in groundwater obtained from both areas were determined prior to applied preconcentration method as reported in our previous works. The Cd and Pb contents in the groundwater of villages of exposed area were found in the range of 5.18-10.9 and 19.9-69.5 µg/L, respectively. Whereas, the groundwater of nonexposed area contains Cd and Pb in the range of 1.79-3.78 and 5.07-24.3 µg/L, respectively. It was observed that the concentrations of Cd and Pb in scalp hair and blood samples of children belongs to exposed area have ≥2.0 fold higher than the resulted data attained for age matched control children, indicating as the exposure biomarkers of toxic metals. The children belong to exposed area have poor health, anemic and low body mass index (<13 kg/m2). A significant positive correlations among Cd and Pb concentrations in biological samples of exposed subjects and groundwater was observed (p < 0.01).


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Metais Pesados/análise , Cádmio/análise , Criança , Feminino , Água Subterrânea , Cabelo/química , Humanos , Mineração , Paquistão/epidemiologia , Couro Cabeludo , Espectrofotometria Atômica
16.
Anal Bioanal Chem ; 411(27): 7251-7260, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31612256

RESUMO

Chloride widely exists in the environment and will cause serious interference for arsenic speciation analysis. The determination of four arsenic species including arsenite (As(III)), arsenate (As(V)), monomethylarsenate (MMA), and dimethylarsonate (DMA) in samples containing high concentrations of Cl- was carried out in this work by coupling of liquid chromatography (LC) with hydride generation atomic fluorescence spectrometry (HG-AFS). The interference of Cl- was successfully eliminated by coupling two anion-exchange chromatographic columns in series and eluting with 35.0 mmol L-1 (NH4)2HPO4 (pH = 6.00). A novel pre-treatment system was subsequently developed to realize on-line column switch and pre-reduction of As(V). The analysis time was shortened by an isocratic elution but programmed flow rate method, and the sensitivity of As(V) was also enhanced by the introduction of pre-reduction using the developed system. The proposed method can resist at least 10 g L-1 Cl- without any pre-treatment operations. Since LC-HG-AFS is low-cost and can be afforded or self-assembled by most labs, the developed method can be adopted as a routine analysis method for arsenic species in chloride-bearing samples, such as urine and seawater. Graphical abstract.


Assuntos
Arseniatos/análise , Arsenicais/análise , Arsenitos/análise , Poluentes Químicos da Água/análise , Arseniatos/urina , Arsênico/análise , Arsênico/urina , Arsenicais/urina , Arsenitos/urina , Cloretos/análise , Cloretos/urina , Cromatografia Líquida de Alta Pressão/instrumentação , Desenho de Equipamento , Humanos , Limite de Detecção , Metilação , Água do Mar/análise , Espectrometria de Fluorescência/instrumentação , Espectrofotometria Atômica/instrumentação , Poluentes Químicos da Água/urina
17.
Environ Monit Assess ; 191(11): 666, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650329

RESUMO

The presence of several trace elements, heavy metals, and antimony in polyethylene terephthalate-bottled local raw cow milk samples of Igdir region in Turkey was investigated. The milk samples were analyzed by inductively coupled plasma mass spectrometry after microwave-assisted digestion. Milk samples were categorized into three groups according to the element level intensity in the sample. While 70% of samples showed 2.5 times the maximum Turkish and European permissible level of lead, the lowest lead-contaminated sample exhibited 1.25 times this level. All the examined samples exceeded the maximum permissible limit administrated for arsenic and 35% of samples exhibited 5 times this limit. Results showed 40% of samples contain an antimony level higher than the Turkish maximum allowable concentration. The high antimony content of raw milk samples may be related to the release of antimony from the PET (polyethylene terephthalate) bottles. This study showed high contamination levels of the most toxic trace elements, i.e., lead and arsenic in milk and possible antimony contamination from PET bottles which may cause many health hazards for the consumers.


Assuntos
Antimônio/análise , Contaminação de Alimentos/análise , Metais Pesados/análise , Leite/química , Oligoelementos/análise , Animais , Arsênico/análise , Bovinos , Monitoramento Ambiental , Feminino , Inocuidade dos Alimentos , Polietilenotereftalatos , Espectrofotometria Atômica , Turquia
18.
Environ Pollut ; 255(Pt 2): 113322, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31610504

RESUMO

Various industrial activities lead to environmental pollution by heavy metals. Toxic heavy metals enter the food chain of dairy cows through feed and water, then transferred into milk. This study investigated the correlations of heavy metal contents between individual cows' milk, water, silage and soil. The relationships between heavy metal contents in individual cows' milk with milk protein, fat, lactose, solid nonfat (SNF), and total solids (TS) were analysed. Concentrations of Pb, As, Cr, and Cd in milk, silage and water were measured by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Lead, Cr, and Cd in soil were measured by Atomic Absorption Spectrometry (AAS), and As was detected by Atomic Fluorescence Spectrometry (AFS). One-way non-parametric tests and Spearman correlation analyses were performed using SAS 9.4 software. Levels of Pb and Cd in milk from the unpolluted area were significantly lower (P < 0.01) than those from industrial area. Significantly higher (P < 0.01) As residue was recorded in milk from unpolluted area. Positive correlation of Pb was observed between milk and silage, and As in milk was positively correlated with As in water. Content of As in milk was slightly (r = 0.09) correlated with As in silage, even though strong positive correlation (r = 0.78) was observed between silage and water. Positive correlations were observed for Cr and Cd between milk and silage, as well as milk and soil. Positive correlations were observed in Pb-protein, Cr-protein, and Cd-lactose; other positive correlation coefficients were nearly equal to zero. The results suggest that industrial activities lead to possible Pb and Cd contamination in milk. Drinking water could be the main source of As contamination in cows. No clear relationship was found between milk composition and heavy metals contents in milk. Water and soil on the farm had a partial contribution to heavy metal contamination in milk.


Assuntos
Metais Pesados/análise , Leite/química , Silagem/análise , Poluentes do Solo/análise , Solo/química , Água/química , Animais , Arsênico/análise , Cádmio/análise , Bovinos , China , Cromo/análise , Monitoramento Ambiental/métodos , Feminino , Chumbo/análise , Espectrofotometria Atômica
19.
Environ Monit Assess ; 191(11): 650, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31624906

RESUMO

Fruits are important components of human diet, and their contamination by environmental pollutants is an emerging challenge nowadays. The present study is based on the measurement of selected essential and toxic trace metals including Na, K, Ca, Mg, Fe, Zn, Cu, Mn, Cr, Co, Sr, Li, Ni, Pb, and Cd in commercially available citrus fruits from Pakistan. The samples were digested in HNO3 and HCLO4 mixture, and the metal contents were quantified by flame atomic absorption spectrometry. Highest concentration was found for Ca (609.0-3596 mg/kg), followed by relatively higher levels of K (277.6-682.1 mg/kg), Mg (53.65-123.4 mg/kg), Na (1.173-52.14 mg/kg), and Fe (0.236-10.57 mg/kg), while Li, Ni, and Cd showed the lowest contributions in most of the samples. In addition, antioxidant activities such as DPPH radical scavenging assay, hydroxyl radical scavenging activity, ferrous chelating activity, ferric reducing antioxidant power assay, and phosphomolybdenum assay were also evaluated in the fruit samples. Considerably higher antioxidant activities were shown by grapefruit, mandarin, sweet lime, and tangerine. Most of the antioxidant assays were significantly correlated with Na, Mg, Fe, Mn, and Cu levels in the fruits. Human health risk was evaluated in terms of health risk index (HRI), target hazard quotient (THQ), and target cancer risk (TCR) which revealed insignificant health risks; thus, the consumption of these fruits can be considered as safe for human diet.


Assuntos
Antioxidantes/análise , Citrus/química , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Metais Pesados/análise , Oligoelementos/análise , Frutas/química , Humanos , Paquistão , Medição de Risco , Espectrofotometria Atômica
20.
Environ Monit Assess ; 191(10): 637, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529162

RESUMO

Cadmium (Cd) and lead (Pb) are ubiquitous metals widely distributed in the environment, resulting in toxic health effects. This project aims to evaluate Pb and Cd as toxic elements in 15 different tobacco cigarette brands produced and/or sold in Selangor state, Peninsular Malaysia. The concentrations of Pb and Cd in all tobacco brands tested in this study were determined using the air-acetylene flame atomic absorption spectrophotometer (AAS). On average, the concentrations of Pb and Cd in different tobacco brand samples ranged from 3.05 and 0.80 µg/g dw, respectively. The results indicate that assessment mean values of Pb inhaled from smoking one packet of 20 cigarettes were in the range of 1.55-3.51 µg. Furthermore, the concentration of Cd inhaled per packet of cigarettes (20 sticks) is estimated to be 0.04-0.36 µg. However, there was a significant difference in the concentrations of Pb and Cd between the different brands of tobacco cigarettes, among cigarette prices (cheap versus expensive) of tobacco brands. In conclusion, cigarette smokers in Selangor, Malaysia, are heavily exposed to Pb and Cd, and such exposure could adversely affect their health in the long term. The impact of toxic heavy metals on smokers in this state would be an area for future research.


Assuntos
Cádmio/análise , Chumbo/análise , Produtos do Tabaco/análise , Comércio , Monitoramento Ambiental , Malásia , Metais Pesados/análise , Fumar , Espectrofotometria Atômica
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