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1.
J Trace Elem Med Biol ; 84: 127442, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38554676

RESUMO

The contents of essential (Ca, Fe, K, Na, P, and Zn) and potentially toxic inorganic elements (As, Al, Cd, Cr, Cu, Mn, and Pb) in enteral and parenteral nutrition formulas were evaluated by inductively coupled plasma optical emission spectrometry (ICP OES) and graphite furnace atomic absorption spectrometry (GFAAS). A total of 30 enteral formulas, 23 parenteral solution components, and 3 parenteral solutions were analyzed. The elements Ca and K presented the higher contents (72-2918 mg L-1 and 235-2760 mg L-1) while the lowest concentration levels were found for As and Cd (<0.68 µg L-1 and <0.01-0.62 µg L-1) in the studied samples. The validated analytical methods presented an accuracy of 75-116% and RSD values lower than 9.8%. Calcium gluconate and magnesium sulfate, which are used as raw materials in parenteral solution, are potential sources of Al and Mn contamination. A Hazard Quotient (HQ) >1 was obtained for Al (27 ± 1 µg L-1) in one of the parenteral samples, whereas the established limit is 25 µg L-1. Enteral samples were considered safe for consumption regarding the Al, As, and Cd levels. One healing-specific and pediatric formula contained Pb at levels above 0.25 µg kg-day-1, too high for safe consumption. The enteral formulas (pediatric, diabetes-specific, renal-specific, healing-specific, and standard formula with addition of fiber) presented risks in relation to the consumption of Cr and Mn (>250 µg day-1 and >11 mg day-1). The results indicate the need for strict monitoring, considering that these formulations are often the single patient's food source.


Assuntos
Nutrição Enteral , Nutrição Parenteral , Medição de Risco , Humanos , Oligoelementos/análise , Espectrofotometria Atômica/métodos , Alimentos Formulados/análise
2.
Molecules ; 27(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36234728

RESUMO

In this work, a rapid detection method using solid sampling electrothermal vaporization atomic absorption spectrometry (SS-ETV-AAS) was established for cadmium in chocolate. The instrumental system includes a solid sampling ETV unit, a catalytic pyrolysis furnace, an AAS detector, and a gas supply system with only an air pump and a hydrogen generator. Herein, MgO material with 1.0−1.5 mm particle size was first employed to replace the kaolin filler previously used to further shorten the peak width and to thereby improve the sensitivity. With 350 mL/min of air, a chocolate sample was heated for 25 s from 435 to 464 °C to remove water and organic matrices; then, after supplying 240 mL/min hydrogen and turning down air to 120 mL/min, a N2/H2 mixture gas was formed to accelerate Cd vaporization from chocolate residue under 465 to 765 °C. Under the optimized conditions, the detection limit (LOD) was obviously lowered to 70 pg/g (vs. previous 150 pg/g) with R2 > 0.999; the relative standard deviations (RSD) of repeated measurements for real chocolate samples ranged from 1.5% to 6.4%, indicating a favorable precision; and the Cd recoveries were in the range of 93−107%, proving a satisfied accuracy. Thus, the total analysis time is less than 3 min without the sample digestion process. Thereafter, 78 chocolate samples with different brands from 9 producing countries in China market were collected and measured by this proposed method. Based on the measured Cd concentrations, a dietary exposure assessment was performed for Chinese residents, and the target hazard quotient (THQ) values are all less than 1, proving no significant health risk from intaking chocolate cadmium for Chinese residents.


Assuntos
Cádmio , Chocolate , Cádmio/análise , Chocolate/análise , Exposição Dietética/análise , Hidrogênio/análise , Caulim , Óxido de Magnésio , Medição de Risco , Espectrofotometria Atômica/métodos , Volatilização , Água/análise
3.
Anal Bioanal Chem ; 414(7): 2409-2418, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35044488

RESUMO

Lead (Pb) is a toxic heavy metal and is commonly used in industrial applications. Thus, Pb poisoning is a concerning public health issue worldwide. The amounts of lead in natural water, urine, and blood can serve as significant indicators for monitoring the exposure of Pb poisoning. Waste toner has the characteristics of both "waste" and "resource," as it is a "resource in the wrong place." Here, a low-cost carboxylate-functionalized magnetic adsorbent was first synthesized from waste toner by a simple thermal treatment and served as a novel adsorbent with a flexible multidentate O-donor for pre-concentration of trace Pb. The characterization, adsorption behavior, and various factors of adsorption and desorption were adequately optimized, and prior to graphite furnace atomic absorption spectrometry (GFAAS) detection, a new magnetic solid-phase extraction method was proposed for the analysis of Pb in real environmental water and biological samples. The developed method exhibited a low detection limit (0.003 µg L-1), high enrichment factor (88.6-fold), good linearity (0.01-0.3 µg L-1), satisfactory precision with relative standard deviations of 7.9% (n = 7, CPb = 0.02 µg L-1), fast adsorption kinetics (5 min), and strong ability to overcome matrix interference. Validation was also performed by analyzing a certified standard reference material, and the method was successfully applied to real tap water, lake water, human urine, and human blood serum with satisfactory recoveries of 92.6-109%.


Assuntos
Chumbo , Poluentes Químicos da Água , Adsorção , Humanos , Fenômenos Magnéticos , Extração em Fase Sólida/métodos , Espectrofotometria Atômica/métodos , Poluentes Químicos da Água/análise
4.
Molecules ; 26(23)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34885663

RESUMO

The present study was conducted to quantify the daily intake and target hazard quotient of four essential elements, namely, chromium, cobalt, nickel, and copper, and four toxic trace elements, mercury, cadmium, lead, and arsenic. Thirty food items were assigned to five food categories (seeds, leaves, powders, beans, and fruits) and analyzed using inductively coupled plasma-mass spectrometry. Factor analysis after principal component extraction revealed common metal patterns in all foodstuffs, and using hierarchical cluster analysis, an association map was created to illustrate their similarity. The results indicate that the internationally recommended dietary allowance was exceeded for Cu and Cr in 27 and 29 foodstuffs, respectively. According to the tolerable upper level for Ni and Cu, everyday consumption of these elements through repeated consumption of seeds (fennel, opium poppy, and cannabis) and fruits (almond) can have adverse health effects. Moreover, a robust correlation between Cu and As (p < 0.001) was established when all samples were analyzed. Principal component analysis (PCA) demonstrated an association between Pb, As, Co, and Ni in one group and Cr, Cu, Hg, and Cd in a second group, comprising 56.85% of the total variance. For all elements investigated, the cancer risk index was within safe limits, highlighting that lifetime consumption does not increase the risk of carcinogens.


Assuntos
Arsênio/análise , Cádmio/análise , Cromo/análise , Cobalto/análise , Cobre/análise , Chumbo/análise , Mercúrio/análise , Níquel/análise , Espectrofotometria Atômica/métodos , Supermercados , Oligoelementos/análise , Humanos , Romênia
5.
PLoS One ; 16(6): e0252834, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34161345

RESUMO

Mushrooms exhibit a high ability to accumulate potentially toxic elements. The legal regulations in force in the European Union countries do not define the maximum content of elements in dried wild-grown mushrooms. This study presents the content of mercury (Hg), lead (Pb), cadmium (Cd) and arsenic (As) determined in dried wild-grown mushrooms (Boletus edulis and Xerocomus badius) available for sale. Moreover, the health risk associated with their consumption is assessed. The inductively coupled plasma mass spectrometry (Cd, Pb, As) and atomic absorption spectrometry (Hg) were used. The mean Hg, Cd, Pb and As concentration in Boletus edulis was 3.039±1.092, 1.983±1.145, 1.156±1.049 and 0.897±0.469 mg/kg and in Xerocomus badius 0.102±0.020, 1.154±0.596, 0.928±1.810 and 0.278±0.108 mg/kg, respectively. The maximum value of the hazard index (HI) showed that the consumption of a standard portion of dried Boletus edulis may have negative consequences for health and corresponded to 76.2%, 34.1%, 33% and 4.3% of the maximum daily doses of Hg, Cd, Pb and As, respectively. The results indicate that the content of toxic elements in dried wild-grown mushrooms should be monitored. The issue constitutes a legal niche where unfavourable EU regulations may pose a threat to food safety and consumer health.


Assuntos
Agaricales/química , Basidiomycota/química , Exposição Dietética/análise , Contaminação de Alimentos/análise , Metais Pesados/análise , Algoritmos , Arsênio/análise , Cádmio/análise , União Europeia , Contaminação de Alimentos/prevenção & controle , Inocuidade dos Alimentos/métodos , Humanos , Chumbo/análise , Mercúrio/análise , Medição de Risco/legislação & jurisprudência , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Espectrofotometria Atômica/métodos
6.
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
7.
Food Chem ; 284: 259-263, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30744855

RESUMO

In this work, an analytical method for the determination of Cd and Pb in natural coconut water samples, industrialized coconut water samples and coconut milk using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS), after minimum treatment of the sample was developed. The analytical method was applied to 46 samples collected in Salvador, Bahia (Brazil). The ranges of concentrations obtained were: 0.42-18.72 µg L-1 Cd and <0.70-36.32 µg L-1 Pb for natural coconut water samples (n = 14); <0.06-1.49 µg L-1 Cd and 6.57-29.02 µg L-1 Pb for industrialized water coconut samples (n = 16); and <0.10-5.93 ng g-1 Cd and <0.85-22.41 ng g-1 Pb for coconut milk samples (n = 16). For all samples, Cd and Pb concentrations were below the maximum tolerated values recommended by Brazilian Health Surveillance Agency (Agência Nacional de Vigilância Sanitária, ANVISA).


Assuntos
Cádmio/análise , Cocos/química , Sucos de Frutas e Vegetais/análise , Chumbo/análise , Espectrofotometria Atômica/métodos , Brasil , Cocos/metabolismo , Grafite/química , Limite de Detecção , Reprodutibilidade dos Testes , Águas Residuárias/análise
8.
Biol Trace Elem Res ; 187(2): 596-601, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29948912

RESUMO

Synchrotron radiation X-ray fluorescence spectroscopy, in conjunction with atomic absorption and Raman spectroscopy, was used to analyze a set of top brand tattoo inks to investigate the presence of toxic elements and hazardous substances. The Cr, Cu, and Pb contents were found to be above the maximum allowed levels established by the Council of Europe through the resolution ResAP(2008)1 on requirements and criteria for the safety of tattoos and permanent makeup. Raman analysis has revealed the presence of a set of prohibited substances mentioned in ResAP(2008)1, among which are the pigments Blue 15, Green 7, and Violet 23. Other pigments that were identified in white, black, red, and yellow inks are the Pigment White 6, Carbon Black, Pigment Red 8, and a diazo yellow, respectively. The present results show the importance of regulating tattoo ink composition.


Assuntos
Substâncias Perigosas/análise , Tinta , Metais/análise , Análise Espectral/métodos , Tatuagem , Cádmio/análise , Cromo/análise , Cobre/análise , Humanos , Chumbo/análise , Mercúrio/análise , Níquel/análise , Espectrometria por Raios X/métodos , Espectrofotometria Atômica/métodos , Análise Espectral Raman/métodos
9.
Rocz Panstw Zakl Hig ; 70(4): 401-406, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31961103

RESUMO

Background: According to the European Food Safety Authority (EFSA), vegetable and vegetable products can significantly contribute to dietary nickel intake. Consumption of vegetable across European Union can vary significantly and depends on consumption habits in individual Member States. Toxicity of Ni is dependent on the chemical form, the route of exposure and solubility of nickel compounds. Objectives: Determination of nickel content in commercially available vegetables and vegetable products and assessment of consumer exposure to Ni intake with these groups of foodstuffs. Materials and methods: 66 samples of vegetables and their products were analysed for nickel content. Nickel was determined after microwave mineralization of samples by atomic absorption spectrometry with a graphite furnace atomization (GFAAS). Nitric acid and perhydrol were used for the mineralization of the samples. The estimated exposure for adults and children was compared with the tolerable daily intake (TDI -Tolerable Daily Intake) set by the European Food Safety Authority at 2.8 µg /kg body weight (b.w.) per day. Results: Mean (MB-middle bound) Ni content from all investigated vegetable samples was 0.09 mg/kg (95th percentile MB 0.23 mg/kg). In vegetable products, mean Ni concentration was 0.191 mg/kg (95th percentile: 0.67 mg/kg). The highest nickel level was determined in the sample of roman lettuce (0.32 mg/kg), whereas lowest contamination was observed in the sample of onion (0.04 mg/kg). Contamination of investigated fruiting and leaf vegetable with nickel was slightly higher than root and bulb vegetables. The estimated average adults exposure to nickel from vegetable taking into account maximum absorption was 4.8% of TDI and 16.8% of TDI and does not pose a health risk. Exposure to nickel from vegetable products was 1.9% and 6.8% TDI, respectively. Conclusions: Obtained results demonstrate that dietary nickel intake from vegetables and their products do not constitute a significant health threat to consumers in Poland.


Assuntos
Exposição Dietética/análise , Contaminação de Alimentos/análise , Níquel/análise , Verduras/anatomia & histologia , Adulto , Criança , Qualidade de Produtos para o Consumidor , Humanos , Nível de Efeito Adverso não Observado , Polônia , Padrões de Referência , Medição de Risco , Espectrofotometria Atômica/métodos
10.
Biol Trace Elem Res ; 182(1): 178-184, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28667513

RESUMO

The aim of this study was to evaluate the bioaccessibility of Ca, Fe, Mg, Mn, and Zn in cat's claw plant teas through in vitro gastrointestinal digestion with gastric and intestinal juice solutions. The total concentrations and bioaccessible fractions of Ca, Fe, Mg, Mn, and Zn were measured by flame atomic absorption spectrometry (FAAS). The results obtained showed that Zn was the most bioaccessible element in the teas, contributing a mean of 57.9% by infusion and 62.5% by decoction. Among macroelements, the Ca was less bioaccessible with 17.4% recovery. The bioavailability assessment revealed that daily intake of 200 ml of cat's claw teas cover about 1.0% of manganese RDA.


Assuntos
Unha-de-Gato/química , Extratos Vegetais/química , Espectrofotometria Atômica/métodos , Oligoelementos/análise , Cálcio/análise , Digestão , Ferro/análise , Magnésio/análise , Plantas Medicinais/química , Recomendações Nutricionais , Zinco/análise
11.
J Sci Food Agric ; 98(8): 2915-2924, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29160899

RESUMO

BACKGROUND: Persistent sample circulation microextraction (PSCME) combined with graphite furnace atomic absorption spectrometry (GFAAS) was developed as a high pre-concentration technique for the determination of heavy metals in fish species. In this method, a few microliters of organic solvent (40.0 µL carbon tetrachloride) was transferred to the bottom of a conical sample cup. Then 10.0 mL of aqueous solution was transformed to fine droplets while passing through the organic solvent. At this stage, metal-ligand hydrophobic complex was extracted into the organic solvent. After extraction, 20 µL of extraction solvent was injected into the graphite tube using an auto-sampler. RESULTS: Under optimal conditions, enrichment factors and enhancement factor were in the range of 180-240 and 155-214, respectively. The calibration curves were linear in the range of 0.03-200 µg kg-1 and the limits of detection (LODs) were in the range of 0.01-0.05 µg kg-1 . Repeatability (intra-day) and reproducibility (inter-day) for 0.50 µg L-1 Hg and 0.10 µg L-1 Cd and Pb were in the range of 3.1-4.2% (n = 7) and 4.3-6.1% (n = 7), respectively. CONCLUSION: Potential human health risk assessment was conducted by calculating estimated weekly intake (EWI) of the metals from eating fish and comparison of these values with provisional tolerable weekly intake (PTWI) values. EWI data for the studied metals through fish consumption were lower than the PTWI values. © 2017 Society of Chemical Industry.


Assuntos
Microextração em Fase Líquida/métodos , Carne/análise , Metais Pesados/análise , Metais Pesados/isolamento & purificação , Espectrofotometria Atômica/métodos , Animais , Peixes/classificação , Peixes/metabolismo , Contaminação de Alimentos/análise , Grafite/química , Humanos , Irã (Geográfico) , Metais Pesados/metabolismo , Medição de Risco
12.
Women Health ; 58(7): 822-833, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28682191

RESUMO

Pregnant and nursing women are at higher risk of zinc deficiency which can have detrimental consequences on health. We assessed blood zinc levels in 72 nursing women from the West Bank of Palestine and investigated the association between sociodemographic variables and blood zinc levels. Blood samples were analyzed for their zinc contents using graphite furnace atomic absorption spectrophotometry. Blood and data collection were performed between July and December 2016. The median blood zinc level was 4.53 mg/L (interquartile range of 0.38 mg/L). In unadjusted analyses, blood zinc levels were higher in nursing women who lived in cities (p-value <.001), had higher household income (p-value <.001), whose husbands had a white collar job (p-value <.05), were nonsmokers (p-value <.05), did not use hair dyes (p-value <.05), and consumed energy beverages (p-value <.001). Multiple linear analysis showed that living in cities and consuming energy beverages remained significantly associated with higher blood zinc levels (p-value <.05). Blood zinc levels were in the range previously reported for similar non-malnourished populations. Nursing women living in cities and those consuming energy beverages tended to have higher blood zinc levels. Urbanized lifestyle might have enhanced blood zinc levels in nursing women.


Assuntos
Estilo de Vida , Características de Residência , Espectrofotometria Atômica/métodos , Zinco/sangue , Adulto , Estudos Transversais , Feminino , Humanos , Oriente Médio , Gravidez/sangue , Gravidez/fisiologia , População Rural , Fatores Socioeconômicos , Inquéritos e Questionários , População Urbana
13.
Radiology ; 285(3): 839-849, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28873047

RESUMO

Purpose To evaluate the speciation of gadolinium-containing species after multiple administrations of the gadolinium-based contrast agents (GBCAs) gadodiamide and gadoteridol and to quantify the amount of intact gadolinium complexes and insoluble gadolinium-containing species. Materials and Methods A total dose of 13.2 mmol per kilogram of body weight of each GBCA was administered in healthy Wistar rats over a period of 8 weeks. Three days after the final administration, rats were sacrificed, and the brains were excised and divided into three portions. Each portion of brain homogenate was divided into two parts, one for determination of the total gadolinium concentration with inductively coupled plasma mass spectrometry and one for determination of the amount of intact GBCA and gadolinium-containing insoluble species. Relaxometric measurements of gadodiamide and gadolinium trichloride in the presence of polysialic acid were also performed. Results The mean total gadolinium concentrations for gadodiamide and gadoteridol, respectively, were 0.317 µg/g ± 0.060 (standard deviation) and 0.048 µg/g ± 0.004 in the cortex, 0.418 µg/g ± 0.078 and 0.051 µg/g ± 0.009 in the subcortical brain, and 0.781 µg/g ± 0.079 and 0.061 µg/g ± 0.012 in the cerebellum. Gadoteridol comprised 100% of the gadolinium species found in rats treated with gadoteridol. In rats treated with gadodiamide, the largest part of gadolinium retained in brain tissue was insoluble species. In the cerebellum, the amount of intact gadodiamide accounts for 18.2% ± 10.6 of the total gadolinium found therein. The mass balance found for gadolinium implies the occurrence of other soluble gadolinium-containing species (approximately 30%). The relaxivity of the gadolinium polysialic acid species formed in vitro was 97.8 mM/sec at 1.5 T and 298 K. Conclusion Gadoteridol was far less retained, and the entire detected gadolinium was intact soluble GBCA, while gadodiamide yielded both soluble and insoluble gadolinium-containing species, with insoluble species dominating. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Encéfalo/metabolismo , Meios de Contraste/administração & dosagem , Meios de Contraste/farmacocinética , Gadolínio/administração & dosagem , Gadolínio/farmacocinética , Espectrofotometria Atômica/métodos , Animais , Química Encefálica , Meios de Contraste/química , Esquema de Medicação , Gadolínio/química , Masculino , Taxa de Depuração Metabólica , Especificidade de Órgãos/fisiologia , Ratos , Ratos Wistar , Solubilidade , Distribuição Tecidual
14.
Anal Chim Acta ; 939: 1-9, 2016 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-27639139

RESUMO

In-vitro physiologically relevant gastrointestinal extraction based on the validated Unified BARGE Method (UBM) is in this work hyphenated to inductively coupled plasma optical emission spectrometry in a batch-flow configuration for real-time monitoring of oral bioaccessibility assays with high temporal resolution. A fully automated flow analyzer is designed to foster in-line filtration of gastrointestinal extracts at predefined times (≤15 min) followed by on-line multi-elemental analysis of bioaccessible micro-nutrients, viz., Cu, Fe and Mn, in well-defined volumes of extracts (300 µL) of transgenic and non-transgenic soybean seeds taken as model samples. The hyphenated flow setup allows for recording of temporal extraction profiles to gain full knowledge of the kinetics of the gastrointestinal digestion processes, including element leaching and concomitant precipitation and complexation reactions hindering bioavailability. Simplification of the overall standard procedure is also feasible by identification of steady-state extraction conditions. Our findings indicate that reliable measurement of oral bioaccessible pools of Cu, Fe and Mn in soybean might be obtained in less than 180 min rather than 240 min as endorsed by UBM. Using a matrix-matched external calibration, limits of detection according to the 3s criteria were 0.5 µg/g for Mn, 0.6 µg/g for Cu and 2.3 µg/g for Fe. Trueness of the automatic bioaccessibility method was confirmed by mass balance validation with recoveries ranging from 87 to 116% regardless of the target element and sample. Cu was the micronutrient with the highest oral bioaccessibility ranging from 73% to 83% (7.5-7.9 µg/g) for non-transgenic and transgenic soybeans, respectively, followed by Mn and Fe within the ranges of 29-31% (10.8-11.4 µg/g) and 11-15% (8-14 µg/g), respectively, regardless of transgenesis. The proposed kinetic method is proven suitable for fast and expedient estimation of the nutritional value of soybeans and elucidation of the potential effect of transgenesis onto bioaccessible fractions of elements.


Assuntos
Trato Gastrointestinal/metabolismo , Glycine max/química , Micronutrientes/metabolismo , Espectrofotometria Atômica/métodos , Disponibilidade Biológica , Cinética
15.
Environ Sci Technol ; 50(6): 3031-8, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26192198

RESUMO

Halogens in the atmosphere play an important role in climate change and also represent a potential health hazard. However, quantification of halogens is not a trivial task, and methods that require minimum sample preparation are interesting alternatives. Hence, the aim of this work was to evaluate the feasibility of direct solid sample analysis using high-resolution continuum source molecular absorption spectrometry (HR-CS MAS) for F determination and electrothermal vaporization-inductively coupled plasma mass spectrometry (ETV-ICP-MS) for simultaneous Cl, Br, and I determination in airborne inhalable particulate matter (PM10) collected in the metropolitan area of Aracaju, Sergipe, Brazil. Analysis using HR-CS MAS was accomplished by monitoring the CaF molecule, which was generated at high temperatures in the graphite furnace after the addition of Ca. Analysis using ETV-ICP-MS was carried out using Ca as chemical modifier/aerosol carrier in order to avoid losses of Cl, Br, and I during the pyrolysis step, with concomitant use of Pd as a permanent modifier. The direct analysis approach resulted in LODs that were proven adequate for halogen determination in PM10, using either standard addition calibration or calibration against a certified reference material. The method allowed the quantification of the halogens in 14 PM10 samples collected in a northeastern coastal city in Brazil. The results demonstrated variations of halogen content according to meteorological conditions, particularly related to rainfall, humidity, and sunlight irradiation.


Assuntos
Halogênios/análise , Espectrometria de Massas/métodos , Material Particulado/análise , Solo/química , Espectrofotometria Atômica/métodos , Poluentes Atmosféricos/análise , Brasil , Calibragem , Monitoramento Ambiental/métodos , Limite de Detecção , Volatilização , Tempo (Meteorologia)
16.
Vojnosanit Pregl ; 72(9): 807-12, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26554113

RESUMO

BACKGROUND/AIM: Due to their low tolerance to pollutants and hand-to-mouth pathways the health risk is very high in children's population. The aim of this study was to evaluate risk to children's health based on the content of heavy metals in urban soil samples from Podgorica, Montenegro. This study included the investigation of several toxic metals such as Pb, Cd, Cu and Zn in soil samples from public parks and playgrounds. METHODS: Sampling was conducted in a period October-November, 2012. Based on cluster analysis, soil samples were divided into two groups related to similarity of metal content at examinated locations: the group I--near by recreational or residential areas of the city, and the group II--near traffic roads. Concentration of toxic metals, in urban soil samples were determined by a graphite furnace atomic absorption spectrometry (Pb and Cd) and by inductively coupled plasma optical emission spectrometry technique after microwave digestion. Due to exposure to urban soil, non-cancerogenic index hazardous index (HI) for children was estimated using 95th percentile values of total metal concentration. The value of the total (ingestion, dermal and inhalation) HI is calculated for maximum, minimum and the average concentration of metals for children. RESULTS: Mean concentrations of Pb, Cd, Cu and Zn in the surface layer of the studied urban soils were 85.91 mg/kg, 2.8 mg/kg and 52.9 mg/kg and 112.5 mg/kg, respectively. Samples from group II showed higher metal content compared to group I. Urbanization and traffic are the main sources of pollution of the urban soils of Podgorica. Most of the samples (93.5%) had a high Pb content, 12.9% of the samples had a higher content of Cd, while Cu and Zn were within the limits prescribed by national legislation. At one location the level of security for lead is HI = 0.8 and very closed to maximum acceptable value of 1. It is probably the result of intensive traffic near by. CONCLUSION: All metals investigated showed relatively higher concentrations at sites that were close to industrial places and high ways. The mean concentrations of Pb and Zn and maximum concentrations of Pb, Cd, and Zn were higher than presented values in the National Regulation.


Assuntos
Proteção da Criança , Monitoramento Ambiental , Metais Pesados , Solo , Criança , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Humanos , Metais Pesados/análise , Metais Pesados/classificação , Montenegro/epidemiologia , Saúde Pública/métodos , Saúde Pública/estatística & dados numéricos , Medição de Risco , Solo/química , Solo/normas , Espectrofotometria Atômica/métodos
17.
Rocz Panstw Zakl Hig ; 66(3): 203-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26400115

RESUMO

BACKGROUND: According to the European Food Safety Authority (EFSA), fish, seafood and seaweeds are foodstuffs that significantly contribute to dietary arsenic intake. With the exception of some algal species, the dominant compounds of arsenic in such food products are the less toxic organic forms. Both the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and EFSA recommend that speciation studies be performed to determine the different chemical forms in which arsenic is present in food due to the differences in their toxicity. Knowing such compositions can thus enable a complete exposure assessment to be made. OBJECTIVES: Determination of total and inorganic arsenic contents in fish, their products, seafood and seaweeds present on the Polish market. This was then followed by an exposure assessment of consumers to inorganic arsenic in these foodstuffs. MATERIAL AND METHODS: Total and inorganic arsenic was determined in 55 samples of fish, their products, seafood as well as seaweeds available on the market. The analytical method was hydride generation atomic absorption spectrometry (HGAAS), after dry ashing of samples and reduction of arsenic to arsenic hydride using sodium borohydride. In order to isolate only the inorganic forms of arsenic prior to mineralisation, samples were subjected to concentrated HCl hydrolysis, followed by reduction with hydrobromic acid and hydrazine sulphate after which triple chloroform extractions and triple 1M HCl re-extractions were performed. Exposure of adults was estimated in relation to the Benchmark Dose Lower Confidence Limit (BMDL0.5) as set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) that resulted in a 0.5% increase in lung cancer (3.0 µg/kg body weight (b.w.) per day). RESULTS: Mean total arsenic content from all investigated fish samples was 0.46 mg/kg (90th percentile 0.94 mg/kg), whilst the inorganic arsenic content never exceeded the detection limit of the analytical method used (0.025 mg/kg). In fish products, mean total arsenic concentration was 1.48 mg/kg (90th percentile: 2.42 mg/kg), whilst in seafood they were 0.87 mg/ kg (90th percentile: 2.23 mg/kg), for inorganic arsenic contamination at the 90th percentile was 0.043 mg/kg with most results however being less than 0.025 mg/kg. The highest inorganic arsenic levels were determined in the Hijiki algal species samples (102.7 mg/kg), whereas the other algal samples gave a mean inorganic concentration of 0.41 mg/kg (90th percentile 0.86 mg/kg). The estimated average adults exposure to inorganic arsenic in fish, seafood and seaweeds was less than 0.5% of the lowest BMDL0.5 dose. Only for the Hijiki seaweed it was at 4.9% BMDL0.5. CONCLUSIONS: Results demonstrate that dietary arsenic intake from fish, seafood and seaweed along with all their products do not constitute a significant health threat to consumers apart from the seaweed species Hizikia fusiformis in which over 40% of all the inorganic arsenic compounds were found.


Assuntos
Arsênio/análise , Contaminação de Alimentos/análise , Alimentos Marinhos/análise , Alga Marinha/química , Adulto , Qualidade de Produtos para o Consumidor , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Padrões de Referência , Espectrofotometria Atômica/métodos
18.
Clin Biochem ; 48(3): 135-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25448028

RESUMO

OBJECTIVES: We developed and validated a simplified sample preparation for the analysis of antimony (Sb), bismuth (Bi), manganese (Mn), and zinc (Zn) in whole blood. This simplification included a reduction in sample volume, removal of a lengthy acidic digestion, and optimization of the internal standard. DESIGN AND METHODS: Measurement of Sb, Bi, Mn and Zn in whole blood was conducted using inductively coupled-plasma mass spectrometry. Method performance characteristics, including intra- and inter-assay imprecision, accuracy, linearity, AMR, sensitivity, carryover, sample stability and assay stability were determined in accordance with clinical laboratory standards. In addition, analytical and clinical recoveries were assessed to investigate comparability between goat blood matrix and pooled patient blood. RESULTS: Established assay performance characteristics included inter- and intra-assay imprecision <4.5% and carryover of <0.04% for all four elements, analytical measurement range of 1 to 25 µg/L (Sb and Bi), 1 to 80 µg/L (Mn), and 50 to 1500 µg/dL (Zn), limit of quantification of 1 µg/L (Sb, Bi, Mn) and 50 µg/dL (Zn) (coefficient of variation <14%), proportional bias of 0.96 and constant bias of -0.28 (Sb), 0.94 and -0.45 (Bi), 1.07 and -0.37 (Mn) and 0.96 and +18.05 (Zn) based upon repeat patient samples, proficiency testing samples, and comparison to an outside reference laboratory. CONCLUSION: This method overcomes the laborious acidic heat digestion previously used and replaces it with a simplified sample preparation involving an alkaline dilution. The method requires minimal sample preparation with the dilution of alkaline diluent and is validated to quantify Sb and Bi from 1 to 25 µg/L, Mn from 1 to 80 µg/L, and Zn from 50 to 1500 µg/dL in whole blood.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Metais Pesados/sangue , Espectrofotometria Atômica/métodos , Métodos Analíticos de Preparação de Amostras/economia , Animais , Antimônio/sangue , Bismuto/sangue , Cabras , Humanos , Manganês/sangue , Reprodutibilidade dos Testes , Zinco/sangue
19.
Chemosphere ; 119: 1361-1364, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24630451

RESUMO

In this work, the bark of holm oak was used as a bioindicator to study the atmospheric distribution of Cr(VI). The chosen method (alkaline extraction and atomic absorption determination) was found in the literature, adapted for use with the matrix involved, and validated. The method had some limits, but provided an excellent estimation of Cr(VI) concentrations with good sensitivity and a reasonable time of analysis and cost. Thirty-four samples of holm oak collected in three areas characterised by different possible sources of pollution (the area near a former chromate production plant, an urban area, and a rural "reference" area) were analysed, obtaining concentrations ranging from 1.54 to 502 µg g(-1) near the industrial plant, ranging from 0.22 to 1.35 µg g(-1) in the urban area, and mostly below the detection limit (0.04 µg g(-1)) in the rural area. The bark of holm oak proved to be a good bioindicator to detect Cr(VI) in the environment. The extraction procedure followed by atomic absorption analysis is simple, provides good sensitivity, and it is suitable for environmental studies.


Assuntos
Poluição do Ar/análise , Cromo/análise , Monitoramento Ambiental/métodos , Casca de Planta/química , Quercus/química , Análise Custo-Benefício , Sensibilidade e Especificidade , Espectrofotometria Atômica/métodos
20.
J Pharm Biomed Anal ; 106: 116-23, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24856919

RESUMO

For pharmaceutical applications, the use of inorganic engineered nanoparticles is of growing interest while silver (Ag) and gold (Au) are the most relevant elements. A few methods were developed recently but the validation and the application testing were quite limited. Therefore, a routinely suitable multi element method for the identification of nanoparticles of different sizes below 100 nm and elemental composition by applying asymmetric flow field flow fraction (AF4) - inductively coupled plasma mass spectrometry (ICPMS) is developed. A complete validation model of the quantification of releasable pharmaceutical relevant inorganic nanoparticles based on Ag and Au is presented for the most relevant aqueous matrices of tap water and domestic waste water. The samples are originated from locations in the Netherlands and it is of great interest to study the unwanted presence of Ag and Au as nanoparticle residues due to possible health and environmental risks. During method development, instability effects are observed for 60 nm and 70 nm Ag ENPs with different capping agents. These effects are studied more closely in relation to matrix effects. Besides the methodological aspects, the obtained analytical results and relevant performance characteristics (e.g. measuring range, limit of detection, repeatability, reproducibility, trueness, and expanded uncertainty of measurement) are determined and discussed. For the chosen aqueous matrices, the results of the performance characteristics are significantly better for Au ENPs in comparison to Ag ENPs; e.g. repeatability and reproducibility are below 10% for all Au ENPs respectively maximal 27% repeatability for larger Ag ENPs. The method is a promising tool for the simultaneous determination of releasable pharmaceutical relevant inorganic nanoparticles.


Assuntos
Água Potável/análise , Nanopartículas Metálicas/química , Espectrofotometria Atômica/métodos , Águas Residuárias/análise , Fracionamento por Campo e Fluxo/métodos , Ouro/química , Tamanho da Partícula , Reprodutibilidade dos Testes , Prata/química
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